Remove from build

Disable zstd on powerpc64
Add test coverage for non-Python globs (#13430 )
2024-09-20 17:28:58 -04:00 · 2024-09-20 17:26:50 -04:00 · 2024-09-20 20:46:00 +00:00 · 2024-09-20 15:59:32 -04:00 · 2024-09-20 15:40:47 -04:00 · 2024-09-20 19:39:36 +00:00
386 changed files with 19519 additions and 3827 deletions
--- a/.github/workflows/publish-docs.yml
+++ b/.github/workflows/publish-docs.yml
@@ -34,10 +34,10 @@ jobs:
      - name: "Set docs version"
        run: |
          version="${{ (inputs.plan != '' && fromJson(inputs.plan).announcement_tag) || inputs.ref }}"
-          # if version is missing, exit with error
-          if [[ -z "$version" ]]; then
-          echo "Can't build docs without a version."
-          exit 1
+          # if version is missing, use 'latest'
+          if [ -z "$version" ]; then
+            echo "Using 'latest' as version"
+            version="latest"
          fi

          # Use version as display name for now
@@ -145,6 +145,7 @@ jobs:
          GITHUB_TOKEN: ${{ secrets.ASTRAL_DOCS_PAT }}
        run: |
          branch_name="${{ env.branch_name }}"
+
          # auto-merge the PR if the build was triggered by a release. Manual builds should be reviewed by a human.
          # give the PR a few seconds to be created before trying to auto-merge it
          sleep 10
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -1,3 +1,5 @@
+# This file was autogenerated by cargo-dist: https://opensource.axo.dev/cargo-dist/
+#
 # Copyright 2022-2024, axodotdev
 # SPDX-License-Identifier: MIT or Apache-2.0
 #
@@ -64,7 +66,7 @@ jobs:
        # we specify bash to get pipefail; it guards against the `curl` command
        # failing. otherwise `sh` won't catch that `curl` returned non-0
        shell: bash
-        run: "curl --proto '=https' --tlsv1.2 -LsSf https://github.com/axodotdev/cargo-dist/releases/download/v0.18.0/cargo-dist-installer.sh | sh"
+        run: "curl --proto '=https' --tlsv1.2 -LsSf https://github.com/axodotdev/cargo-dist/releases/download/v0.22.1/cargo-dist-installer.sh | sh"
      - name: Cache cargo-dist
        uses: actions/upload-artifact@v4
        with:
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -45,7 +45,7 @@ repos:
          )$

  - repo: https://github.com/crate-ci/typos
-    rev: v1.24.1
+    rev: v1.24.5
    hooks:
      - id: typos

@@ -59,7 +59,7 @@ repos:
        pass_filenames: false # This makes it a lot faster

  - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.6.2
+    rev: v0.6.5
    hooks:
      - id: ruff-format
      - id: ruff
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,90 @@
 # Changelog

+## 0.6.6
+
+### Preview features
+
+- \[`refurb`\] Skip `slice-to-remove-prefix-or-suffix` (`FURB188`) when non-trivial slice steps are present ([#13405](https://github.com/astral-sh/ruff/pull/13405))
+- Add a subcommand to generate dependency graphs ([#13402](https://github.com/astral-sh/ruff/pull/13402))
+
+### Formatter
+
+- Fix placement of inline parameter comments ([#13379](https://github.com/astral-sh/ruff/pull/13379))
+
+### Server
+
+- Fix off-by one error in the `LineIndex::offset` calculation ([#13407](https://github.com/astral-sh/ruff/pull/13407))
+
+### Bug fixes
+
+- \[`fastapi`\] Respect FastAPI aliases in route definitions ([#13394](https://github.com/astral-sh/ruff/pull/13394))
+- \[`pydocstyle`\] Respect word boundaries when detecting function signature in docs ([#13388](https://github.com/astral-sh/ruff/pull/13388))
+
+### Documentation
+
+- Add backlinks to rule overview linter ([#13368](https://github.com/astral-sh/ruff/pull/13368))
+- Fix documentation for editor vim plugin ALE ([#13348](https://github.com/astral-sh/ruff/pull/13348))
+- Fix rendering of `FURB188` docs ([#13406](https://github.com/astral-sh/ruff/pull/13406))
+
+## 0.6.5
+
+### Preview features
+
+- \[`pydoclint`\] Ignore `DOC201` when function name is "**new**" ([#13300](https://github.com/astral-sh/ruff/pull/13300))
+- \[`refurb`\] Implement `slice-to-remove-prefix-or-suffix` (`FURB188`) ([#13256](https://github.com/astral-sh/ruff/pull/13256))
+
+### Rule changes
+
+- \[`eradicate`\] Ignore script-comments with multiple end-tags (`ERA001`) ([#13283](https://github.com/astral-sh/ruff/pull/13283))
+- \[`pyflakes`\] Improve error message for `UndefinedName` when a builtin was added in a newer version than specified in Ruff config (`F821`) ([#13293](https://github.com/astral-sh/ruff/pull/13293))
+
+### Server
+
+- Add support for extensionless Python files for server ([#13326](https://github.com/astral-sh/ruff/pull/13326))
+- Fix configuration inheritance for configurations specified in the LSP settings ([#13285](https://github.com/astral-sh/ruff/pull/13285))
+
+### Bug fixes
+
+- \[`ruff`\] Handle unary operators in `decimal-from-float-literal` (`RUF032`) ([#13275](https://github.com/astral-sh/ruff/pull/13275))
+
+### CLI
+
+- Only include rules with diagnostics in SARIF metadata ([#13268](https://github.com/astral-sh/ruff/pull/13268))
+
+### Playground
+
+- Add "Copy as pyproject.toml/ruff.toml" and "Paste from TOML" ([#13328](https://github.com/astral-sh/ruff/pull/13328))
+- Fix errors not shown for restored snippet on page load ([#13262](https://github.com/astral-sh/ruff/pull/13262))
+
+## 0.6.4
+
+### Preview features
+
+- \[`flake8-builtins`\] Use dynamic builtins list based on Python version ([#13172](https://github.com/astral-sh/ruff/pull/13172))
+- \[`pydoclint`\] Permit yielding `None` in `DOC402` and `DOC403` ([#13148](https://github.com/astral-sh/ruff/pull/13148))
+- \[`pylint`\] Update diagnostic message for `PLW3201` ([#13194](https://github.com/astral-sh/ruff/pull/13194))
+- \[`ruff`\] Implement `post-init-default` (`RUF033`) ([#13192](https://github.com/astral-sh/ruff/pull/13192))
+- \[`ruff`\] Implement useless if-else (`RUF034`) ([#13218](https://github.com/astral-sh/ruff/pull/13218))
+
+### Rule changes
+
+- \[`flake8-pyi`\] Respect `pep8_naming.classmethod-decorators` settings when determining if a method is a classmethod in `custom-type-var-return-type` (`PYI019`) ([#13162](https://github.com/astral-sh/ruff/pull/13162))
+- \[`flake8-pyi`\] Teach various rules that annotations might be stringized ([#12951](https://github.com/astral-sh/ruff/pull/12951))
+- \[`pylint`\] Avoid `no-self-use` for `attrs`-style validators ([#13166](https://github.com/astral-sh/ruff/pull/13166))
+- \[`pylint`\] Recurse into subscript subexpressions when searching for list/dict lookups (`PLR1733`, `PLR1736`) ([#13186](https://github.com/astral-sh/ruff/pull/13186))
+- \[`pyupgrade`\] Detect `aiofiles.open` calls in `UP015` ([#13173](https://github.com/astral-sh/ruff/pull/13173))
+- \[`pyupgrade`\] Mark `sys.version_info[0] < 3` and similar comparisons as outdated (`UP036`) ([#13175](https://github.com/astral-sh/ruff/pull/13175))
+
+### CLI
+
+- Enrich messages of SARIF results ([#13180](https://github.com/astral-sh/ruff/pull/13180))
+- Handle singular case for incompatible rules warning in `ruff format` output ([#13212](https://github.com/astral-sh/ruff/pull/13212))
+
+### Bug fixes
+
+- \[`pydocstyle`\] Improve heuristics for detecting Google-style docstrings ([#13142](https://github.com/astral-sh/ruff/pull/13142))
+- \[`refurb`\] Treat `sep` arguments with effects as unsafe removals (`FURB105`) ([#13165](https://github.com/astral-sh/ruff/pull/13165))
+
 ## 0.6.3

 ### Preview features
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -161,6 +161,21 @@ version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "96d30a06541fbafbc7f82ed10c06164cfbd2c401138f6addd8404629c4b16711"

+[[package]]
+name = "assert_fs"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7efdb1fdb47602827a342857666feb372712cbc64b414172bd6b167a02927674"
+dependencies = [
+ "anstyle",
+ "doc-comment",
+ "globwalk",
+ "predicates",
+ "predicates-core",
+ "predicates-tree",
+ "tempfile",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.2.0"
@@ -194,6 +209,15 @@ version = "2.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"

+[[package]]
+name = "block-buffer"
+version = "0.10.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3078c7629b62d3f0439517fa394996acacc5cbc91c5a20d8c658e77abd503a71"
+dependencies = [
+ "generic-array",
+]
+
 [[package]]
 name = "bstr"
 version = "1.10.0"
@@ -231,6 +255,9 @@ name = "camino"
 version = "1.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8b96ec4966b5813e2c0507c1f86115c8c5abaadc3980879c3424042a02fd1ad3"
+dependencies = [
+ "serde",
+]

 [[package]]
 name = "cast"
@@ -511,6 +538,15 @@ dependencies = [
 "rustc-hash 1.1.0",
 ]

+[[package]]
+name = "cpufeatures"
+version = "0.2.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "51e852e6dc9a5bed1fae92dd2375037bf2b768725bf3be87811edee3249d09ad"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "crc32fast"
 version = "1.4.0"
@@ -616,6 +652,16 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7a81dae078cea95a014a339291cec439d2f232ebe854a9d672b796c6afafa9b7"

+[[package]]
+name = "crypto-common"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1bfb12502f3fc46cca1bb51ac28df9d618d813cdc3d2f25b9fe775a34af26bb3"
+dependencies = [
+ "generic-array",
+ "typenum",
+]
+
 [[package]]
 name = "ctrlc"
 version = "3.4.5"
@@ -694,6 +740,22 @@ version = "0.1.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "56254986775e3233ffa9c4d7d3faaf6d36a2c09d30b20687e9f88bc8bafc16c8"

+[[package]]
+name = "difflib"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6184e33543162437515c2e2b48714794e37845ec9851711914eec9d308f6ebe8"
+
+[[package]]
+name = "digest"
+version = "0.10.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
+dependencies = [
+ "block-buffer",
+ "crypto-common",
+]
+
 [[package]]
 name = "dirs"
 version = "4.0.0"
@@ -735,6 +797,12 @@ dependencies = [
 "windows-sys 0.48.0",
 ]

+[[package]]
+name = "doc-comment"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
+
 [[package]]
 name = "drop_bomb"
 version = "0.1.5"
@@ -879,6 +947,16 @@ dependencies = [
 "libc",
 ]

+[[package]]
+name = "generic-array"
+version = "0.14.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85649ca51fd72272d7821adaf274ad91c288277713d9c18820d8499a7ff69e9a"
+dependencies = [
+ "typenum",
+ "version_check",
+]
+
 [[package]]
 name = "getopts"
 version = "0.2.21"
@@ -920,6 +998,17 @@ dependencies = [
 "regex-syntax 0.8.3",
 ]

+[[package]]
+name = "globwalk"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0bf760ebf69878d9fd8f110c89703d90ce35095324d1f1edcb595c63945ee757"
+dependencies = [
+ "bitflags 2.6.0",
+ "ignore",
+ "walkdir",
+]
+
 [[package]]
 name = "half"
 version = "2.4.1"
@@ -1112,6 +1201,8 @@ dependencies = [
 "globset",
 "lazy_static",
 "linked-hash-map",
+ "pest",
+ "pest_derive",
 "regex",
 "serde",
 "similar",
@@ -1707,6 +1798,51 @@ version = "2.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e3148f5046208a5d56bcfc03053e3ca6334e51da8dfb19b6cdc8b306fae3283e"

+[[package]]
+name = "pest"
+version = "2.7.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd53dff83f26735fdc1ca837098ccf133605d794cdae66acfc2bfac3ec809d95"
+dependencies = [
+ "memchr",
+ "thiserror",
+ "ucd-trie",
+]
+
+[[package]]
+name = "pest_derive"
+version = "2.7.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2a548d2beca6773b1c244554d36fcf8548a8a58e74156968211567250e48e49a"
+dependencies = [
+ "pest",
+ "pest_generator",
+]
+
+[[package]]
+name = "pest_generator"
+version = "2.7.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3c93a82e8d145725dcbaf44e5ea887c8a869efdcc28706df2d08c69e17077183"
+dependencies = [
+ "pest",
+ "pest_meta",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "pest_meta"
+version = "2.7.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a941429fea7e08bedec25e4f6785b6ffaacc6b755da98df5ef3e7dcf4a124c4f"
+dependencies = [
+ "once_cell",
+ "pest",
+ "sha2",
+]
+
 [[package]]
 name = "phf"
 version = "0.11.2"
@@ -1769,6 +1905,33 @@ version = "0.2.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"

+[[package]]
+name = "predicates"
+version = "3.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7e9086cc7640c29a356d1a29fd134380bee9d8f79a17410aa76e7ad295f42c97"
+dependencies = [
+ "anstyle",
+ "difflib",
+ "predicates-core",
+]
+
+[[package]]
+name = "predicates-core"
+version = "1.0.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ae8177bee8e75d6846599c6b9ff679ed51e882816914eec639944d7c9aa11931"
+
+[[package]]
+name = "predicates-tree"
+version = "1.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41b740d195ed3166cd147c8047ec98db0e22ec019eb8eeb76d343b795304fb13"
+dependencies = [
+ "predicates-core",
+ "termtree",
+]
+
 [[package]]
 name = "pretty_assertions"
 version = "1.4.0"
@@ -1803,9 +1966,9 @@ dependencies = [

 [[package]]
 name = "quick-junit"
-version = "0.4.0"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cfc1a6a5406a114913df2df8507998c755311b55b78584bed5f6e88f6417c4d4"
+checksum = "62ffd2f9a162cfae131bed6d9d1ed60adced33be340a94f96952897d7cb0c240"
 dependencies = [
 "chrono",
 "indexmap",
@@ -1818,9 +1981,9 @@ dependencies = [

 [[package]]
 name = "quick-xml"
-version = "0.31.0"
+version = "0.36.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1004a344b30a54e2ee58d66a71b32d2db2feb0a31f9a2d302bf0536f15de2a33"
+checksum = "96a05e2e8efddfa51a84ca47cec303fac86c8541b686d37cac5efc0e094417bc"
 dependencies = [
 "memchr",
 ]
@@ -1936,6 +2099,7 @@ dependencies = [
 "smallvec",
 "static_assertions",
 "tempfile",
+ "test-case",
 "thiserror",
 "tracing",
 "walkdir",
@@ -1997,6 +2161,7 @@ dependencies = [
 "ruff_text_size",
 "rustc-hash 2.0.0",
 "salsa",
+ "tempfile",
 "tracing",
 ]

@@ -2090,10 +2255,11 @@ dependencies = [

 [[package]]
 name = "ruff"
-version = "0.6.3"
+version = "0.6.6"
 dependencies = [
 "anyhow",
 "argfile",
+ "assert_fs",
 "bincode",
 "bitflags 2.6.0",
 "cachedir",
@@ -2103,7 +2269,9 @@ dependencies = [
 "clearscreen",
 "colored",
 "filetime",
+ "globwalk",
 "ignore",
+ "indoc",
 "insta",
 "insta-cmd",
 "is-macro",
@@ -2115,7 +2283,9 @@ dependencies = [
 "rayon",
 "regex",
 "ruff_cache",
+ "ruff_db",
 "ruff_diagnostics",
+ "ruff_graph",
 "ruff_linter",
 "ruff_macros",
 "ruff_notebook",
@@ -2198,6 +2368,7 @@ dependencies = [
 "ruff_text_size",
 "rustc-hash 2.0.0",
 "salsa",
+ "serde",
 "tempfile",
 "thiserror",
 "tracing",
@@ -2273,6 +2444,23 @@ dependencies = [
 "unicode-width",
 ]

+[[package]]
+name = "ruff_graph"
+version = "0.1.0"
+dependencies = [
+ "anyhow",
+ "clap",
+ "red_knot_python_semantic",
+ "ruff_cache",
+ "ruff_db",
+ "ruff_linter",
+ "ruff_macros",
+ "ruff_python_ast",
+ "salsa",
+ "schemars",
+ "serde",
+]
+
 [[package]]
 name = "ruff_index"
 version = "0.0.0"
@@ -2283,7 +2471,7 @@ dependencies = [

 [[package]]
 name = "ruff_linter"
-version = "0.6.3"
+version = "0.6.6"
 dependencies = [
 "aho-corasick",
 "annotate-snippets 0.9.2",
@@ -2603,7 +2791,7 @@ dependencies = [

 [[package]]
 name = "ruff_wasm"
-version = "0.6.3"
+version = "0.6.6"
 dependencies = [
 "console_error_panic_hook",
 "console_log",
@@ -2646,6 +2834,7 @@ dependencies = [
 "regex",
 "ruff_cache",
 "ruff_formatter",
+ "ruff_graph",
 "ruff_linter",
 "ruff_macros",
 "ruff_python_ast",
@@ -2934,6 +3123,17 @@ dependencies = [
 "syn",
 ]

+[[package]]
+name = "sha2"
+version = "0.10.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "793db75ad2bcafc3ffa7c68b215fee268f537982cd901d132f89c6343f3a3dc8"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
+
 [[package]]
 name = "sharded-slab"
 version = "0.1.7"
@@ -3089,6 +3289,12 @@ dependencies = [
 "phf_codegen",
 ]

+[[package]]
+name = "termtree"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3369f5ac52d5eb6ab48c6b4ffdc8efbcad6b89c765749064ba298f2c68a16a76"
+
 [[package]]
 name = "test-case"
 version = "3.3.1"
@@ -3334,6 +3540,18 @@ version = "2.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6af6ae20167a9ece4bcb41af5b80f8a1f1df981f6391189ce00fd257af04126a"

+[[package]]
+name = "typenum"
+version = "1.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "42ff0bf0c66b8238c6f3b578df37d0b7848e55df8577b3f74f92a69acceeb825"
+
+[[package]]
+name = "ucd-trie"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ed646292ffc8188ef8ea4d1e0e0150fb15a5c2e12ad9b8fc191ae7a8a7f3c4b9"
+
 [[package]]
 name = "unic-char-property"
 version = "0.9.0"
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,6 +17,7 @@ ruff_cache = { path = "crates/ruff_cache" }
 ruff_db = { path = "crates/ruff_db" }
 ruff_diagnostics = { path = "crates/ruff_diagnostics" }
 ruff_formatter = { path = "crates/ruff_formatter" }
+ruff_graph = { path = "crates/ruff_graph" }
 ruff_index = { path = "crates/ruff_index" }
 ruff_linter = { path = "crates/ruff_linter" }
 ruff_macros = { path = "crates/ruff_macros" }
@@ -42,6 +43,7 @@ red_knot_workspace = { path = "crates/red_knot_workspace" }
 aho-corasick = { version = "1.1.3" }
 annotate-snippets = { version = "0.9.2", features = ["color"] }
 anyhow = { version = "1.0.80" }
+assert_fs = { version = "1.1.0" }
 argfile = { version = "0.2.0" }
 bincode = { version = "1.3.3" }
 bitflags = { version = "2.5.0" }
@@ -68,6 +70,7 @@ fern = { version = "0.6.1" }
 filetime = { version = "0.2.23" }
 glob = { version = "0.3.1" }
 globset = { version = "0.4.14" }
+globwalk = { version = "0.9.1" }
 hashbrown = "0.14.3"
 ignore = { version = "0.4.22" }
 imara-diff = { version = "0.1.5" }
@@ -102,7 +105,7 @@ pep440_rs = { version = "0.6.0", features = ["serde"] }
 pretty_assertions = "1.3.0"
 proc-macro2 = { version = "1.0.79" }
 pyproject-toml = { version = "0.9.0" }
-quick-junit = { version = "0.4.0" }
+quick-junit = { version = "0.5.0" }
 quote = { version = "1.0.23" }
 rand = { version = "0.8.5" }
 rayon = { version = "1.10.0" }
@@ -230,9 +233,9 @@ inherits = "release"
 # Config for 'cargo dist'
 [workspace.metadata.dist]
 # The preferred cargo-dist version to use in CI (Cargo.toml SemVer syntax)
-cargo-dist-version = "0.18.0"
+cargo-dist-version = "0.22.1"
 # CI backends to support
-ci = ["github"]
+ci = "github"
 # The installers to generate for each app
 installers = ["shell", "powershell"]
 # The archive format to use for windows builds (defaults .zip)
@@ -263,11 +266,11 @@ targets = [
 auto-includes = false
 # Whether cargo-dist should create a GitHub Release or use an existing draft
 create-release = true
-# Publish jobs to run in CI
+# Which actions to run on pull requests
 pr-run-mode = "skip"
 # Whether CI should trigger releases with dispatches instead of tag pushes
 dispatch-releases = true
-# The stage during which the GitHub Release should be created
+# Which phase cargo-dist should use to create the GitHub release
 github-release = "announce"
 # Whether CI should include auto-generated code to build local artifacts
 build-local-artifacts = false
@@ -275,9 +278,11 @@ build-local-artifacts = false
 local-artifacts-jobs = ["./build-binaries", "./build-docker"]
 # Publish jobs to run in CI
 publish-jobs = ["./publish-pypi", "./publish-wasm"]
-# Announcement jobs to run in CI
+# Post-announce jobs to run in CI
 post-announce-jobs = ["./notify-dependents", "./publish-docs", "./publish-playground"]
 # Custom permissions for GitHub Jobs
 github-custom-job-permissions = { "build-docker" = { packages = "write", contents = "read" }, "publish-wasm" = { contents = "read", id-token = "write", packages = "write" } }
 # Whether to install an updater program
 install-updater = false
+# Path that installers should place binaries in
+install-path = "CARGO_HOME"
--- a/README.md
+++ b/README.md
@@ -136,8 +136,8 @@ curl -LsSf https://astral.sh/ruff/install.sh | sh
 powershell -c "irm https://astral.sh/ruff/install.ps1 | iex"

 # For a specific version.
-curl -LsSf https://astral.sh/ruff/0.6.3/install.sh | sh
-powershell -c "irm https://astral.sh/ruff/0.6.3/install.ps1 | iex"
+curl -LsSf https://astral.sh/ruff/0.6.6/install.sh | sh
+powershell -c "irm https://astral.sh/ruff/0.6.6/install.ps1 | iex"
 ```

 You can also install Ruff via [Homebrew](https://formulae.brew.sh/formula/ruff), [Conda](https://anaconda.org/conda-forge/ruff),
@@ -170,7 +170,7 @@ Ruff can also be used as a [pre-commit](https://pre-commit.com/) hook via [`ruff
 ```yaml
 - repo: https://github.com/astral-sh/ruff-pre-commit
  # Ruff version.
-  rev: v0.6.3
+  rev: v0.6.6
  hooks:
    # Run the linter.
    - id: ruff
--- a/crates/red_knot_python_semantic/Cargo.toml
+++ b/crates/red_knot_python_semantic/Cargo.toml
@@ -33,11 +33,17 @@ rustc-hash = { workspace = true }
 hashbrown = { workspace = true }
 smallvec = { workspace = true }
 static_assertions = { workspace = true }
+test-case = { workspace = true }

 [build-dependencies]
 path-slash = { workspace = true }
 walkdir = { workspace = true }
-zip = { workspace = true, features = ["zstd", "deflate"] }
+
+[target.'cfg(not(target_arch = "powerpc64"))'.build-dependencies]
+zip = { workspace = true, features = ["deflate", "zstd"] }
+
+[target.'cfg(target_arch = "powerpc64")'.build-dependencies]
+zip = { workspace = true, features = ["deflate"] }

 [dev-dependencies]
 ruff_db = { workspace = true, features = ["os", "testing"] }
--- a/crates/red_knot_python_semantic/build.rs
+++ b/crates/red_knot_python_semantic/build.rs
@@ -30,10 +30,17 @@ fn zip_dir(directory_path: &str, writer: File) -> ZipResult<File> {
    // We can't use `#[cfg(...)]` here because the target-arch in a build script is the
    // architecture of the system running the build script and not the architecture of the build-target.
    // That's why we use the `TARGET` environment variable here.
-    let method = if std::env::var("TARGET").unwrap().contains("wasm32") {
-        CompressionMethod::Deflated
-    } else {
-        CompressionMethod::Zstd
+    #[cfg(target_arch = "powerpc64")]
+    let method = CompressionMethod::Deflated;
+
+    #[cfg(not(target_arch = "powerpc64"))]
+    let method = {
+        let target = std::env::var("TARGET").unwrap();
+        if target.contains("wasm32") || target.contains("powerpc64") {
+            CompressionMethod::Deflated
+        } else {
+            CompressionMethod::Zstd
+        }
    };

    let options = FileOptions::default()
--- a/crates/red_knot_python_semantic/src/ast_node_ref.rs
+++ b/crates/red_knot_python_semantic/src/ast_node_ref.rs
@@ -31,10 +31,10 @@ impl<T> AstNodeRef<T> {
    /// which the `AstNodeRef` belongs.
    ///
    /// ## Safety
+    ///
    /// Dereferencing the `node` can result in undefined behavior if `parsed` isn't the
    /// [`ParsedModule`] to which `node` belongs. It's the caller's responsibility to ensure that
    /// the invariant `node belongs to parsed` is upheld.
-
    pub(super) unsafe fn new(parsed: ParsedModule, node: &T) -> Self {
        Self {
            _parsed: parsed,
--- a/crates/red_knot_python_semantic/src/builtins.rs
+++ b/crates/red_knot_python_semantic/src/builtins.rs
@@ -1,16 +0,0 @@
-use crate::module_name::ModuleName;
-use crate::module_resolver::resolve_module;
-use crate::semantic_index::global_scope;
-use crate::semantic_index::symbol::ScopeId;
-use crate::Db;
-
-/// Salsa query to get the builtins scope.
-///
-/// Can return None if a custom typeshed is used that is missing `builtins.pyi`.
-#[salsa::tracked]
-pub(crate) fn builtins_scope(db: &dyn Db) -> Option<ScopeId<'_>> {
-    let builtins_name =
-        ModuleName::new_static("builtins").expect("Expected 'builtins' to be a valid module name");
-    let builtins_file = resolve_module(db, builtins_name)?.file();
-    Some(global_scope(db, builtins_file))
-}
--- a/crates/red_knot_python_semantic/src/lib.rs
+++ b/crates/red_knot_python_semantic/src/lib.rs
@@ -4,13 +4,14 @@ use rustc_hash::FxHasher;

 pub use db::Db;
 pub use module_name::ModuleName;
-pub use module_resolver::{resolve_module, system_module_search_paths, vendored_typeshed_stubs};
+pub use module_resolver::{
+    resolve_module, system_module_search_paths, vendored_typeshed_stubs, Module,
+};
 pub use program::{Program, ProgramSettings, SearchPathSettings, SitePackages};
 pub use python_version::PythonVersion;
 pub use semantic_model::{HasTy, SemanticModel};

 pub mod ast_node_ref;
-mod builtins;
 mod db;
 mod module_name;
 mod module_resolver;
@@ -20,6 +21,7 @@ mod python_version;
 pub mod semantic_index;
 mod semantic_model;
 pub(crate) mod site_packages;
+mod stdlib;
 pub mod types;

 type FxOrderSet<V> = ordermap::set::OrderSet<V, BuildHasherDefault<FxHasher>>;
--- a/crates/red_knot_python_semantic/src/module_resolver/mod.rs
+++ b/crates/red_knot_python_semantic/src/module_resolver/mod.rs
@@ -1,6 +1,6 @@
 use std::iter::FusedIterator;

-pub(crate) use module::Module;
+pub use module::Module;
 pub use resolver::resolve_module;
 pub(crate) use resolver::{file_to_module, SearchPaths};
 use ruff_db::system::SystemPath;
--- a/crates/red_knot_python_semantic/src/module_resolver/path.rs
+++ b/crates/red_knot_python_semantic/src/module_resolver/path.rs
@@ -59,6 +59,10 @@ impl ModulePath {
        self.relative_path.push(component);
    }

+    pub(crate) fn pop(&mut self) -> bool {
+        self.relative_path.pop()
+    }
+
    #[must_use]
    pub(super) fn is_directory(&self, resolver: &ResolverContext) -> bool {
        let ModulePath {
--- a/crates/red_knot_python_semantic/src/module_resolver/resolver.rs
+++ b/crates/red_knot_python_semantic/src/module_resolver/resolver.rs
@@ -569,24 +569,16 @@ fn resolve_name(db: &dyn Db, name: &ModuleName) -> Option<(SearchPath, File, Mod

                package_path.push(module_name);

-                // Must be a `__init__.pyi` or `__init__.py` or it isn't a package.
-                let kind = if package_path.is_directory(&resolver_state) {
-                    package_path.push("__init__");
-                    ModuleKind::Package
-                } else {
-                    ModuleKind::Module
-                };
-
-                // TODO Implement full https://peps.python.org/pep-0561/#type-checker-module-resolution-order resolution
-                if let Some(stub) = package_path.with_pyi_extension().to_file(&resolver_state) {
-                    return Some((search_path.clone(), stub, kind));
+                // Check for a regular package first (highest priority)
+                package_path.push("__init__");
+                if let Some(regular_package) = resolve_file_module(&package_path, &resolver_state) {
+                    return Some((search_path.clone(), regular_package, ModuleKind::Package));
                }

-                if let Some(module) = package_path
-                    .with_py_extension()
-                    .and_then(|path| path.to_file(&resolver_state))
-                {
-                    return Some((search_path.clone(), module, kind));
+                // Check for a file module next
+                package_path.pop();
+                if let Some(file_module) = resolve_file_module(&package_path, &resolver_state) {
+                    return Some((search_path.clone(), file_module, ModuleKind::Module));
                }

                // For regular packages, don't search the next search path. All files of that
@@ -607,6 +599,23 @@ fn resolve_name(db: &dyn Db, name: &ModuleName) -> Option<(SearchPath, File, Mod
    None
 }

+/// If `module` exists on disk with either a `.pyi` or `.py` extension,
+/// return the [`File`] corresponding to that path.
+///
+/// `.pyi` files take priority, as they always have priority when
+/// resolving modules.
+fn resolve_file_module(module: &ModulePath, resolver_state: &ResolverContext) -> Option<File> {
+    // Stubs have precedence over source files
+    module
+        .with_pyi_extension()
+        .to_file(resolver_state)
+        .or_else(|| {
+            module
+                .with_py_extension()
+                .and_then(|path| path.to_file(resolver_state))
+        })
+}
+
 fn resolve_package<'a, 'db, I>(
    module_search_path: &SearchPath,
    components: I,
@@ -633,7 +642,10 @@ where

        if is_regular_package {
            in_namespace_package = false;
-        } else if package_path.is_directory(resolver_state) {
+        } else if package_path.is_directory(resolver_state)
+            // Pure modules hide namespace packages with the same name
+            && resolve_file_module(&package_path, resolver_state).is_none()
+        {
            // A directory without an `__init__.py` is a namespace package, continue with the next folder.
            in_namespace_package = true;
        } else if in_namespace_package {
@@ -1091,6 +1103,25 @@ mod tests {
        );
    }

+    #[test]
+    fn single_file_takes_priority_over_namespace_package() {
+        //const SRC: &[FileSpec] = &[("foo.py", "x = 1")];
+        const SRC: &[FileSpec] = &[("foo.py", "x = 1"), ("foo/bar.py", "x = 2")];
+
+        let TestCase { db, src, .. } = TestCaseBuilder::new().with_src_files(SRC).build();
+
+        let foo_module_name = ModuleName::new_static("foo").unwrap();
+        let foo_bar_module_name = ModuleName::new_static("foo.bar").unwrap();
+
+        // `foo.py` takes priority over the `foo` namespace package
+        let foo_module = resolve_module(&db, foo_module_name.clone()).unwrap();
+        assert_eq!(foo_module.file().path(&db), &src.join("foo.py"));
+
+        // `foo.bar` isn't recognised as a module
+        let foo_bar_module = resolve_module(&db, foo_bar_module_name.clone());
+        assert_eq!(foo_bar_module, None);
+    }
+
    #[test]
    fn typing_stub_over_module() {
        const SRC: &[FileSpec] = &[("foo.py", "print('Hello, world!')"), ("foo.pyi", "x: int")];
--- a/crates/red_knot_python_semantic/src/python_version.rs
+++ b/crates/red_knot_python_semantic/src/python_version.rs
@@ -54,6 +54,13 @@ impl TryFrom<(&str, &str)> for PythonVersion {
    }
 }

+impl From<(u8, u8)> for PythonVersion {
+    fn from(value: (u8, u8)) -> Self {
+        let (major, minor) = value;
+        Self { major, minor }
+    }
+}
+
 impl fmt::Display for PythonVersion {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let PythonVersion { major, minor } = self;
--- a/crates/red_knot_python_semantic/src/semantic_index.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index.rs
@@ -21,12 +21,15 @@ use crate::Db;

 pub mod ast_ids;
 mod builder;
+pub(crate) mod constraint;
 pub mod definition;
 pub mod expression;
 pub mod symbol;
 mod use_def;

-pub(crate) use self::use_def::{DefinitionWithConstraints, DefinitionWithConstraintsIterator};
+pub(crate) use self::use_def::{
+    BindingWithConstraints, BindingWithConstraintsIterator, DeclarationsIterator,
+};

 type SymbolMap = hashbrown::HashMap<ScopedSymbolId, (), ()>;

@@ -112,6 +115,9 @@ pub(crate) struct SemanticIndex<'db> {
    /// Note: We should not depend on this map when analysing other files or
    /// changing a file invalidates all dependents.
    ast_ids: IndexVec<FileScopeId, AstIds>,
+
+    /// Flags about the global scope (code usage impacting inference)
+    has_future_annotations: bool,
 }

 impl<'db> SemanticIndex<'db> {
@@ -212,6 +218,12 @@ impl<'db> SemanticIndex<'db> {
    pub(crate) fn node_scope(&self, node: NodeWithScopeRef) -> FileScopeId {
        self.scopes_by_node[&node.node_key()]
    }
+
+    /// Checks if there is an import of `__future__.annotations` in the global scope, which affects
+    /// the logic for type inference.
+    pub(super) fn has_future_annotations(&self) -> bool {
+        self.has_future_annotations
+    }
 }

 pub struct AncestorsIter<'a> {
@@ -325,16 +337,16 @@ mod tests {
    use crate::Db;

    impl UseDefMap<'_> {
-        fn first_public_definition(&self, symbol: ScopedSymbolId) -> Option<Definition<'_>> {
-            self.public_definitions(symbol)
+        fn first_public_binding(&self, symbol: ScopedSymbolId) -> Option<Definition<'_>> {
+            self.public_bindings(symbol)
                .next()
-                .map(|constrained_definition| constrained_definition.definition)
+                .map(|constrained_binding| constrained_binding.binding)
        }

-        fn first_use_definition(&self, use_id: ScopedUseId) -> Option<Definition<'_>> {
-            self.use_definitions(use_id)
+        fn first_binding_at_use(&self, use_id: ScopedUseId) -> Option<Definition<'_>> {
+            self.bindings_at_use(use_id)
                .next()
-                .map(|constrained_definition| constrained_definition.definition)
+                .map(|constrained_binding| constrained_binding.binding)
        }
    }

@@ -396,8 +408,8 @@ mod tests {
        let foo = global_table.symbol_id_by_name("foo").unwrap();

        let use_def = use_def_map(&db, scope);
-        let definition = use_def.first_public_definition(foo).unwrap();
-        assert!(matches!(definition.node(&db), DefinitionKind::Import(_)));
+        let binding = use_def.first_public_binding(foo).unwrap();
+        assert!(matches!(binding.kind(&db), DefinitionKind::Import(_)));
    }

    #[test]
@@ -426,22 +438,19 @@ mod tests {
        assert!(
            global_table
                .symbol_by_name("foo")
-                .is_some_and(|symbol| { symbol.is_defined() && !symbol.is_used() }),
+                .is_some_and(|symbol| { symbol.is_bound() && !symbol.is_used() }),
            "symbols that are defined get the defined flag"
        );

        let use_def = use_def_map(&db, scope);
-        let definition = use_def
-            .first_public_definition(
+        let binding = use_def
+            .first_public_binding(
                global_table
                    .symbol_id_by_name("foo")
                    .expect("symbol to exist"),
            )
            .unwrap();
-        assert!(matches!(
-            definition.node(&db),
-            DefinitionKind::ImportFrom(_)
-        ));
+        assert!(matches!(binding.kind(&db), DefinitionKind::ImportFrom(_)));
    }

    #[test]
@@ -454,17 +463,14 @@ mod tests {
        assert!(
            global_table
                .symbol_by_name("foo")
-                .is_some_and(|symbol| { !symbol.is_defined() && symbol.is_used() }),
-            "a symbol used but not defined in a scope should have only the used flag"
+                .is_some_and(|symbol| { !symbol.is_bound() && symbol.is_used() }),
+            "a symbol used but not bound in a scope should have only the used flag"
        );
        let use_def = use_def_map(&db, scope);
-        let definition = use_def
-            .first_public_definition(global_table.symbol_id_by_name("x").expect("symbol exists"))
+        let binding = use_def
+            .first_public_binding(global_table.symbol_id_by_name("x").expect("symbol exists"))
            .unwrap();
-        assert!(matches!(
-            definition.node(&db),
-            DefinitionKind::Assignment(_)
-        ));
+        assert!(matches!(binding.kind(&db), DefinitionKind::Assignment(_)));
    }

    #[test]
@@ -476,12 +482,12 @@ mod tests {
        assert_eq!(names(&global_table), vec!["x"]);

        let use_def = use_def_map(&db, scope);
-        let definition = use_def
-            .first_public_definition(global_table.symbol_id_by_name("x").unwrap())
+        let binding = use_def
+            .first_public_binding(global_table.symbol_id_by_name("x").unwrap())
            .unwrap();

        assert!(matches!(
-            definition.node(&db),
+            binding.kind(&db),
            DefinitionKind::AugmentedAssignment(_)
        ));
    }
@@ -514,13 +520,10 @@ y = 2
        assert_eq!(names(&class_table), vec!["x"]);

        let use_def = index.use_def_map(class_scope_id);
-        let definition = use_def
-            .first_public_definition(class_table.symbol_id_by_name("x").expect("symbol exists"))
+        let binding = use_def
+            .first_public_binding(class_table.symbol_id_by_name("x").expect("symbol exists"))
            .unwrap();
-        assert!(matches!(
-            definition.node(&db),
-            DefinitionKind::Assignment(_)
-        ));
+        assert!(matches!(binding.kind(&db), DefinitionKind::Assignment(_)));
    }

    #[test]
@@ -550,17 +553,14 @@ y = 2
        assert_eq!(names(&function_table), vec!["x"]);

        let use_def = index.use_def_map(function_scope_id);
-        let definition = use_def
-            .first_public_definition(
+        let binding = use_def
+            .first_public_binding(
                function_table
                    .symbol_id_by_name("x")
                    .expect("symbol exists"),
            )
            .unwrap();
-        assert!(matches!(
-            definition.node(&db),
-            DefinitionKind::Assignment(_)
-        ));
+        assert!(matches!(binding.kind(&db), DefinitionKind::Assignment(_)));
    }

    #[test]
@@ -592,27 +592,27 @@ def f(a: str, /, b: str, c: int = 1, *args, d: int = 2, **kwargs):

        let use_def = index.use_def_map(function_scope_id);
        for name in ["a", "b", "c", "d"] {
-            let definition = use_def
-                .first_public_definition(
+            let binding = use_def
+                .first_public_binding(
                    function_table
                        .symbol_id_by_name(name)
                        .expect("symbol exists"),
                )
                .unwrap();
            assert!(matches!(
-                definition.node(&db),
+                binding.kind(&db),
                DefinitionKind::ParameterWithDefault(_)
            ));
        }
        for name in ["args", "kwargs"] {
-            let definition = use_def
-                .first_public_definition(
+            let binding = use_def
+                .first_public_binding(
                    function_table
                        .symbol_id_by_name(name)
                        .expect("symbol exists"),
                )
                .unwrap();
-            assert!(matches!(definition.node(&db), DefinitionKind::Parameter(_)));
+            assert!(matches!(binding.kind(&db), DefinitionKind::Parameter(_)));
        }
    }

@@ -640,23 +640,19 @@ def f(a: str, /, b: str, c: int = 1, *args, d: int = 2, **kwargs):

        let use_def = index.use_def_map(lambda_scope_id);
        for name in ["a", "b", "c", "d"] {
-            let definition = use_def
-                .first_public_definition(
-                    lambda_table.symbol_id_by_name(name).expect("symbol exists"),
-                )
+            let binding = use_def
+                .first_public_binding(lambda_table.symbol_id_by_name(name).expect("symbol exists"))
                .unwrap();
            assert!(matches!(
-                definition.node(&db),
+                binding.kind(&db),
                DefinitionKind::ParameterWithDefault(_)
            ));
        }
        for name in ["args", "kwargs"] {
-            let definition = use_def
-                .first_public_definition(
-                    lambda_table.symbol_id_by_name(name).expect("symbol exists"),
-                )
+            let binding = use_def
+                .first_public_binding(lambda_table.symbol_id_by_name(name).expect("symbol exists"))
                .unwrap();
-            assert!(matches!(definition.node(&db), DefinitionKind::Parameter(_)));
+            assert!(matches!(binding.kind(&db), DefinitionKind::Parameter(_)));
        }
    }

@@ -666,7 +662,7 @@ def f(a: str, /, b: str, c: int = 1, *args, d: int = 2, **kwargs):
    fn comprehension_scope() {
        let TestCase { db, file } = test_case(
            "
-[x for x in iter1]
+[x for x, y in iter1]
 ",
        );

@@ -690,7 +686,22 @@ def f(a: str, /, b: str, c: int = 1, *args, d: int = 2, **kwargs):

        let comprehension_symbol_table = index.symbol_table(comprehension_scope_id);

-        assert_eq!(names(&comprehension_symbol_table), vec!["x"]);
+        assert_eq!(names(&comprehension_symbol_table), vec!["x", "y"]);
+
+        let use_def = index.use_def_map(comprehension_scope_id);
+        for name in ["x", "y"] {
+            let binding = use_def
+                .first_public_binding(
+                    comprehension_symbol_table
+                        .symbol_id_by_name(name)
+                        .expect("symbol exists"),
+                )
+                .unwrap();
+            assert!(matches!(
+                binding.kind(&db),
+                DefinitionKind::Comprehension(_)
+            ));
+        }
    }

    /// Test case to validate that the `x` variable used in the comprehension is referencing the
@@ -726,12 +737,12 @@ def f(a: str, /, b: str, c: int = 1, *args, d: int = 2, **kwargs):
        let element_use_id =
            element.scoped_use_id(&db, comprehension_scope_id.to_scope_id(&db, file));

-        let definition = use_def.first_use_definition(element_use_id).unwrap();
-        let DefinitionKind::Comprehension(comprehension) = definition.node(&db) else {
+        let binding = use_def.first_binding_at_use(element_use_id).unwrap();
+        let DefinitionKind::Comprehension(comprehension) = binding.kind(&db) else {
            panic!("expected generator definition")
        };
-        let ast::Comprehension { target, .. } = comprehension.node();
-        let name = target.as_name_expr().unwrap().id().as_str();
+        let target = comprehension.target();
+        let name = target.id().as_str();

        assert_eq!(name, "x");
        assert_eq!(target.range(), TextRange::new(23.into(), 24.into()));
@@ -806,12 +817,10 @@ with item1 as x, item2 as y:

        let use_def = index.use_def_map(FileScopeId::global());
        for name in ["x", "y"] {
-            let Some(definition) = use_def.first_public_definition(
-                global_table.symbol_id_by_name(name).expect("symbol exists"),
-            ) else {
-                panic!("Expected with item definition for {name}");
-            };
-            assert!(matches!(definition.node(&db), DefinitionKind::WithItem(_)));
+            let binding = use_def
+                .first_public_binding(global_table.symbol_id_by_name(name).expect("symbol exists"))
+                .expect("Expected with item definition for {name}");
+            assert!(matches!(binding.kind(&db), DefinitionKind::WithItem(_)));
        }
    }

@@ -831,12 +840,10 @@ with context() as (x, y):

        let use_def = index.use_def_map(FileScopeId::global());
        for name in ["x", "y"] {
-            let Some(definition) = use_def.first_public_definition(
-                global_table.symbol_id_by_name(name).expect("symbol exists"),
-            ) else {
-                panic!("Expected with item definition for {name}");
-            };
-            assert!(matches!(definition.node(&db), DefinitionKind::WithItem(_)));
+            let binding = use_def
+                .first_public_binding(global_table.symbol_id_by_name(name).expect("symbol exists"))
+                .expect("Expected with item definition for {name}");
+            assert!(matches!(binding.kind(&db), DefinitionKind::WithItem(_)));
        }
    }

@@ -873,14 +880,14 @@ def func():
        assert_eq!(names(&func2_table), vec!["y"]);

        let use_def = index.use_def_map(FileScopeId::global());
-        let definition = use_def
-            .first_public_definition(
+        let binding = use_def
+            .first_public_binding(
                global_table
                    .symbol_id_by_name("func")
                    .expect("symbol exists"),
            )
            .unwrap();
-        assert!(matches!(definition.node(&db), DefinitionKind::Function(_)));
+        assert!(matches!(binding.kind(&db), DefinitionKind::Function(_)));
    }

    #[test]
@@ -948,7 +955,7 @@ class C[T]:
        assert!(
            ann_table
                .symbol_by_name("T")
-                .is_some_and(|s| s.is_defined() && !s.is_used()),
+                .is_some_and(|s| s.is_bound() && !s.is_used()),
            "type parameters are defined by the scope that introduces them"
        );

@@ -980,8 +987,8 @@ class C[T]:
        };
        let x_use_id = x_use_expr_name.scoped_use_id(&db, scope);
        let use_def = use_def_map(&db, scope);
-        let definition = use_def.first_use_definition(x_use_id).unwrap();
-        let DefinitionKind::Assignment(assignment) = definition.node(&db) else {
+        let binding = use_def.first_binding_at_use(x_use_id).unwrap();
+        let DefinitionKind::Assignment(assignment) = binding.kind(&db) else {
            panic!("should be an assignment definition")
        };
        let ast::Expr::NumberLiteral(ast::ExprNumberLiteral {
@@ -1029,7 +1036,7 @@ class C[T]:
        }

        let TestCase { db, file } = test_case(
-            r#"
+            r"
 class Test:
    def foo():
        def bar():
@@ -1038,7 +1045,7 @@ class Test:
        pass

 def x():
-    pass"#,
+    pass",
        );

        let index = semantic_index(&db, file);
@@ -1073,7 +1080,7 @@ def x():
    }

    #[test]
-    fn match_stmt_symbols() {
+    fn match_stmt() {
        let TestCase { db, file } = test_case(
            "
 match subject:
@@ -1087,13 +1094,69 @@ match subject:
 ",
        );

-        let global_table = symbol_table(&db, global_scope(&db, file));
+        let global_scope_id = global_scope(&db, file);
+        let global_table = symbol_table(&db, global_scope_id);

        assert!(global_table.symbol_by_name("Foo").unwrap().is_used());
        assert_eq!(
            names(&global_table),
-            vec!["subject", "a", "b", "c", "d", "f", "e", "h", "g", "Foo", "i", "j", "k", "l"]
+            vec!["subject", "a", "b", "c", "d", "e", "f", "g", "h", "Foo", "i", "j", "k", "l"]
        );
+
+        let use_def = use_def_map(&db, global_scope_id);
+        for (name, expected_index) in [
+            ("a", 0),
+            ("b", 0),
+            ("c", 1),
+            ("d", 2),
+            ("e", 0),
+            ("f", 1),
+            ("g", 0),
+            ("h", 1),
+            ("i", 0),
+            ("j", 1),
+            ("k", 0),
+            ("l", 1),
+        ] {
+            let binding = use_def
+                .first_public_binding(global_table.symbol_id_by_name(name).expect("symbol exists"))
+                .expect("Expected with item definition for {name}");
+            if let DefinitionKind::MatchPattern(pattern) = binding.kind(&db) {
+                assert_eq!(pattern.index(), expected_index);
+            } else {
+                panic!("Expected match pattern definition for {name}");
+            }
+        }
+    }
+
+    #[test]
+    fn nested_match_case() {
+        let TestCase { db, file } = test_case(
+            "
+match 1:
+    case first:
+        match 2:
+            case second:
+                pass
+",
+        );
+
+        let global_scope_id = global_scope(&db, file);
+        let global_table = symbol_table(&db, global_scope_id);
+
+        assert_eq!(names(&global_table), vec!["first", "second"]);
+
+        let use_def = use_def_map(&db, global_scope_id);
+        for (name, expected_index) in [("first", 0), ("second", 0)] {
+            let binding = use_def
+                .first_public_binding(global_table.symbol_id_by_name(name).expect("symbol exists"))
+                .expect("Expected with item definition for {name}");
+            if let DefinitionKind::MatchPattern(pattern) = binding.kind(&db) {
+                assert_eq!(pattern.index(), expected_index);
+            } else {
+                panic!("Expected match pattern definition for {name}");
+            }
+        }
    }

    #[test]
@@ -1105,11 +1168,11 @@ match subject:
        assert_eq!(&names(&global_table), &["a", "x"]);

        let use_def = use_def_map(&db, scope);
-        let definition = use_def
-            .first_public_definition(global_table.symbol_id_by_name("x").unwrap())
+        let binding = use_def
+            .first_public_binding(global_table.symbol_id_by_name("x").unwrap())
            .unwrap();

-        assert!(matches!(definition.node(&db), DefinitionKind::For(_)));
+        assert!(matches!(binding.kind(&db), DefinitionKind::For(_)));
    }

    #[test]
@@ -1121,15 +1184,15 @@ match subject:
        assert_eq!(&names(&global_table), &["a", "x", "y"]);

        let use_def = use_def_map(&db, scope);
-        let x_definition = use_def
-            .first_public_definition(global_table.symbol_id_by_name("x").unwrap())
+        let x_binding = use_def
+            .first_public_binding(global_table.symbol_id_by_name("x").unwrap())
            .unwrap();
-        let y_definition = use_def
-            .first_public_definition(global_table.symbol_id_by_name("y").unwrap())
+        let y_binding = use_def
+            .first_public_binding(global_table.symbol_id_by_name("y").unwrap())
            .unwrap();

-        assert!(matches!(x_definition.node(&db), DefinitionKind::For(_)));
-        assert!(matches!(y_definition.node(&db), DefinitionKind::For(_)));
+        assert!(matches!(x_binding.kind(&db), DefinitionKind::For(_)));
+        assert!(matches!(y_binding.kind(&db), DefinitionKind::For(_)));
    }

    #[test]
@@ -1141,10 +1204,10 @@ match subject:
        assert_eq!(&names(&global_table), &["e", "a", "b", "c", "d"]);

        let use_def = use_def_map(&db, scope);
-        let definition = use_def
-            .first_public_definition(global_table.symbol_id_by_name("a").unwrap())
+        let binding = use_def
+            .first_public_binding(global_table.symbol_id_by_name("a").unwrap())
            .unwrap();

-        assert!(matches!(definition.node(&db), DefinitionKind::For(_)));
+        assert!(matches!(binding.kind(&db), DefinitionKind::For(_)));
    }
 }
--- a/crates/red_knot_python_semantic/src/semantic_index/builder.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/builder.rs
@@ -19,14 +19,18 @@ use crate::semantic_index::definition::{
 };
 use crate::semantic_index::expression::Expression;
 use crate::semantic_index::symbol::{
-    FileScopeId, NodeWithScopeKey, NodeWithScopeRef, Scope, ScopeId, ScopedSymbolId, SymbolFlags,
+    FileScopeId, NodeWithScopeKey, NodeWithScopeRef, Scope, ScopeId, ScopedSymbolId,
    SymbolTableBuilder,
 };
 use crate::semantic_index::use_def::{FlowSnapshot, UseDefMapBuilder};
 use crate::semantic_index::SemanticIndex;
 use crate::Db;

-use super::definition::WithItemDefinitionNodeRef;
+use super::constraint::{Constraint, PatternConstraint};
+use super::definition::{
+    DefinitionCategory, ExceptHandlerDefinitionNodeRef, MatchPatternDefinitionNodeRef,
+    WithItemDefinitionNodeRef,
+};

 pub(super) struct SemanticIndexBuilder<'db> {
    // Builder state
@@ -36,9 +40,14 @@ pub(super) struct SemanticIndexBuilder<'db> {
    scope_stack: Vec<FileScopeId>,
    /// The assignment we're currently visiting.
    current_assignment: Option<CurrentAssignment<'db>>,
+    /// The match case we're currently visiting.
+    current_match_case: Option<CurrentMatchCase<'db>>,
    /// Flow states at each `break` in the current loop.
    loop_break_states: Vec<FlowSnapshot>,

+    /// Flags about the file's global scope
+    has_future_annotations: bool,
+
    // Semantic Index fields
    scopes: IndexVec<FileScopeId, Scope>,
    scope_ids_by_scope: IndexVec<FileScopeId, ScopeId<'db>>,
@@ -59,8 +68,11 @@ impl<'db> SemanticIndexBuilder<'db> {
            module: parsed,
            scope_stack: Vec::new(),
            current_assignment: None,
+            current_match_case: None,
            loop_break_states: vec![],

+            has_future_annotations: false,
+
            scopes: IndexVec::new(),
            symbol_tables: IndexVec::new(),
            ast_ids: IndexVec::new(),
@@ -162,49 +174,95 @@ impl<'db> SemanticIndexBuilder<'db> {
        self.current_use_def_map_mut().merge(state);
    }

-    fn add_or_update_symbol(&mut self, name: Name, flags: SymbolFlags) -> ScopedSymbolId {
-        let symbol_table = self.current_symbol_table();
-        let (symbol_id, added) = symbol_table.add_or_update_symbol(name, flags);
+    fn add_symbol(&mut self, name: Name) -> ScopedSymbolId {
+        let (symbol_id, added) = self.current_symbol_table().add_symbol(name);
        if added {
-            let use_def_map = self.current_use_def_map_mut();
-            use_def_map.add_symbol(symbol_id);
+            self.current_use_def_map_mut().add_symbol(symbol_id);
        }
        symbol_id
    }

+    fn mark_symbol_bound(&mut self, id: ScopedSymbolId) {
+        self.current_symbol_table().mark_symbol_bound(id);
+    }
+
+    fn mark_symbol_used(&mut self, id: ScopedSymbolId) {
+        self.current_symbol_table().mark_symbol_used(id);
+    }
+
    fn add_definition<'a>(
        &mut self,
        symbol: ScopedSymbolId,
        definition_node: impl Into<DefinitionNodeRef<'a>>,
    ) -> Definition<'db> {
        let definition_node: DefinitionNodeRef<'_> = definition_node.into();
+        #[allow(unsafe_code)]
+        // SAFETY: `definition_node` is guaranteed to be a child of `self.module`
+        let kind = unsafe { definition_node.into_owned(self.module.clone()) };
+        let category = kind.category();
        let definition = Definition::new(
            self.db,
            self.file,
            self.current_scope(),
            symbol,
-            #[allow(unsafe_code)]
-            unsafe {
-                definition_node.into_owned(self.module.clone())
-            },
+            kind,
            countme::Count::default(),
        );

-        self.definitions_by_node
+        let existing_definition = self
+            .definitions_by_node
            .insert(definition_node.key(), definition);
-        self.current_use_def_map_mut()
-            .record_definition(symbol, definition);
+        debug_assert_eq!(existing_definition, None);
+
+        if category.is_binding() {
+            self.mark_symbol_bound(symbol);
+        }
+
+        let use_def = self.current_use_def_map_mut();
+        match category {
+            DefinitionCategory::DeclarationAndBinding => {
+                use_def.record_declaration_and_binding(symbol, definition);
+            }
+            DefinitionCategory::Declaration => use_def.record_declaration(symbol, definition),
+            DefinitionCategory::Binding => use_def.record_binding(symbol, definition),
+        }

        definition
    }

-    fn add_constraint(&mut self, constraint_node: &ast::Expr) -> Expression<'db> {
+    fn add_expression_constraint(&mut self, constraint_node: &ast::Expr) -> Expression<'db> {
        let expression = self.add_standalone_expression(constraint_node);
-        self.current_use_def_map_mut().record_constraint(expression);
+        self.current_use_def_map_mut()
+            .record_constraint(Constraint::Expression(expression));

        expression
    }

+    fn add_pattern_constraint(
+        &mut self,
+        subject: &ast::Expr,
+        pattern: &ast::Pattern,
+    ) -> PatternConstraint<'db> {
+        #[allow(unsafe_code)]
+        let (subject, pattern) = unsafe {
+            (
+                AstNodeRef::new(self.module.clone(), subject),
+                AstNodeRef::new(self.module.clone(), pattern),
+            )
+        };
+        let pattern_constraint = PatternConstraint::new(
+            self.db,
+            self.file,
+            self.current_scope(),
+            subject,
+            pattern,
+            countme::Count::default(),
+        );
+        self.current_use_def_map_mut()
+            .record_constraint(Constraint::Pattern(pattern_constraint));
+        pattern_constraint
+    }
+
    /// Record an expression that needs to be a Salsa ingredient, because we need to infer its type
    /// standalone (type narrowing tests, RHS of an assignment.)
    fn add_standalone_expression(&mut self, expression_node: &ast::Expr) -> Expression<'db> {
@@ -249,10 +307,13 @@ impl<'db> SemanticIndexBuilder<'db> {
                        ..
                    }) => (name, &None, default),
                };
-                // TODO create Definition for typevars
-                self.add_or_update_symbol(name.id.clone(), SymbolFlags::IS_DEFINED);
-                if let Some(bound) = bound {
-                    self.visit_expr(bound);
+                let symbol = self.add_symbol(name.id.clone());
+                // TODO create Definition for PEP 695 typevars
+                // note that the "bound" on the typevar is a totally different thing than whether
+                // or not a name is "bound" by a typevar declaration; the latter is always true.
+                self.mark_symbol_bound(symbol);
+                if let Some(bounds) = bound {
+                    self.visit_expr(bounds);
                }
                if let Some(default) = default {
                    self.visit_expr(default);
@@ -269,11 +330,23 @@ impl<'db> SemanticIndexBuilder<'db> {
        nested_scope
    }

-    /// Visit a list of [`Comprehension`] nodes, assumed to be the "generators" that compose a
-    /// comprehension (that is, the `for x in y` and `for y in z` parts of `x for x in y for y in z`.)
+    /// This method does several things:
+    /// - It pushes a new scope onto the stack for visiting
+    ///   a list/dict/set comprehension or generator expression
+    /// - Inside that scope, it visits a list of [`Comprehension`] nodes,
+    ///   assumed to be the "generators" that compose a comprehension
+    ///   (that is, the `for x in y` and `for y in z` parts of `x for x in y for y in z`).
+    /// - Inside that scope, it also calls a closure for visiting the outer `elt`
+    ///   of a list/dict/set comprehension or generator expression
+    /// - It then pops the new scope off the stack
    ///
    /// [`Comprehension`]: ast::Comprehension
-    fn visit_generators(&mut self, scope: NodeWithScopeRef, generators: &'db [ast::Comprehension]) {
+    fn with_generators_scope(
+        &mut self,
+        scope: NodeWithScopeRef,
+        generators: &'db [ast::Comprehension],
+        visit_outer_elt: impl FnOnce(&mut Self),
+    ) {
        let mut generators_iter = generators.iter();

        let Some(generator) = generators_iter.next() else {
@@ -282,6 +355,7 @@ impl<'db> SemanticIndexBuilder<'db> {

        // The `iter` of the first generator is evaluated in the outer scope, while all subsequent
        // nodes are evaluated in the inner scope.
+        self.add_standalone_expression(&generator.iter);
        self.visit_expr(&generator.iter);
        self.push_scope(scope);

@@ -297,6 +371,7 @@ impl<'db> SemanticIndexBuilder<'db> {
        }

        for generator in generators_iter {
+            self.add_standalone_expression(&generator.iter);
            self.visit_expr(&generator.iter);

            self.current_assignment = Some(CurrentAssignment::Comprehension {
@@ -310,11 +385,13 @@ impl<'db> SemanticIndexBuilder<'db> {
                self.visit_expr(expr);
            }
        }
+
+        visit_outer_elt(self);
+        self.pop_scope();
    }

    fn declare_parameter(&mut self, parameter: AnyParameterRef) {
-        let symbol =
-            self.add_or_update_symbol(parameter.name().id().clone(), SymbolFlags::IS_DEFINED);
+        let symbol = self.add_symbol(parameter.name().id().clone());

        let definition = self.add_definition(symbol, parameter);

@@ -322,10 +399,11 @@ impl<'db> SemanticIndexBuilder<'db> {
            // Insert a mapping from the parameter to the same definition.
            // This ensures that calling `HasTy::ty` on the inner parameter returns
            // a valid type (and doesn't panic)
-            self.definitions_by_node.insert(
+            let existing_definition = self.definitions_by_node.insert(
                DefinitionNodeRef::from(AnyParameterRef::Variadic(&with_default.parameter)).key(),
                definition,
            );
+            debug_assert_eq!(existing_definition, None);
        }
    }

@@ -377,6 +455,7 @@ impl<'db> SemanticIndexBuilder<'db> {
            scopes_by_expression: self.scopes_by_expression,
            scopes_by_node: self.scopes_by_node,
            use_def_maps,
+            has_future_annotations: self.has_future_annotations,
        }
    }
 }
@@ -424,8 +503,7 @@ where
                // The symbol for the function name itself has to be evaluated
                // at the end to match the runtime evaluation of parameter defaults
                // and return-type annotations.
-                let symbol = self
-                    .add_or_update_symbol(function_def.name.id.clone(), SymbolFlags::IS_DEFINED);
+                let symbol = self.add_symbol(function_def.name.id.clone());
                self.add_definition(symbol, function_def);
            }
            ast::Stmt::ClassDef(class) => {
@@ -433,8 +511,7 @@ where
                    self.visit_decorator(decorator);
                }

-                let symbol =
-                    self.add_or_update_symbol(class.name.id.clone(), SymbolFlags::IS_DEFINED);
+                let symbol = self.add_symbol(class.name.id.clone());
                self.add_definition(symbol, class);

                self.with_type_params(
@@ -460,7 +537,7 @@ where
                        Name::new(alias.name.id.split('.').next().unwrap())
                    };

-                    let symbol = self.add_or_update_symbol(symbol_name, SymbolFlags::IS_DEFINED);
+                    let symbol = self.add_symbol(symbol_name);
                    self.add_definition(symbol, alias);
                }
            }
@@ -472,8 +549,16 @@ where
                        &alias.name.id
                    };

-                    let symbol =
-                        self.add_or_update_symbol(symbol_name.clone(), SymbolFlags::IS_DEFINED);
+                    // Look for imports `from __future__ import annotations`, ignore `as ...`
+                    // We intentionally don't enforce the rules about location of `__future__`
+                    // imports here, we assume the user's intent was to apply the `__future__`
+                    // import, so we still check using it (and will also emit a diagnostic about a
+                    // miss-placed `__future__` import.)
+                    self.has_future_annotations |= alias.name.id == "annotations"
+                        && node.module.as_deref() == Some("__future__");
+
+                    let symbol = self.add_symbol(symbol_name.clone());
+
                    self.add_definition(symbol, ImportFromDefinitionNodeRef { node, alias_index });
                }
            }
@@ -489,7 +574,6 @@ where
            }
            ast::Stmt::AnnAssign(node) => {
                debug_assert!(self.current_assignment.is_none());
-                // TODO deferred annotation visiting
                self.visit_expr(&node.annotation);
                if let Some(value) = &node.value {
                    self.visit_expr(value);
@@ -515,7 +599,7 @@ where
            ast::Stmt::If(node) => {
                self.visit_expr(&node.test);
                let pre_if = self.flow_snapshot();
-                self.add_constraint(&node.test);
+                self.add_expression_constraint(&node.test);
                self.visit_body(&node.body);
                let mut post_clauses: Vec<FlowSnapshot> = vec![];
                for clause in &node.elif_else_clauses {
@@ -540,14 +624,23 @@ where
                    self.flow_merge(pre_if);
                }
            }
-            ast::Stmt::While(node) => {
-                self.visit_expr(&node.test);
+            ast::Stmt::While(ast::StmtWhile {
+                test,
+                body,
+                orelse,
+                range: _,
+            }) => {
+                self.visit_expr(test);

                let pre_loop = self.flow_snapshot();

                // Save aside any break states from an outer loop
                let saved_break_states = std::mem::take(&mut self.loop_break_states);
-                self.visit_body(&node.body);
+
+                // TODO: definitions created inside the body should be fully visible
+                // to other statements/expressions inside the body --Alex/Carl
+                self.visit_body(body);
+
                // Get the break states from the body of this loop, and restore the saved outer
                // ones.
                let break_states =
@@ -556,7 +649,7 @@ where
                // We may execute the `else` clause without ever executing the body, so merge in
                // the pre-loop state before visiting `else`.
                self.flow_merge(pre_loop);
-                self.visit_body(&node.orelse);
+                self.visit_body(orelse);

                // Breaking out of a while loop bypasses the `else` clause, so merge in the break
                // states after visiting `else`.
@@ -590,15 +683,111 @@ where
                    orelse,
                },
            ) => {
-                // TODO add control flow similar to `ast::Stmt::While` above
                self.add_standalone_expression(iter);
                self.visit_expr(iter);
+
+                let pre_loop = self.flow_snapshot();
+                let saved_break_states = std::mem::take(&mut self.loop_break_states);
+
                debug_assert!(self.current_assignment.is_none());
                self.current_assignment = Some(for_stmt.into());
                self.visit_expr(target);
                self.current_assignment = None;
+
+                // TODO: Definitions created by loop variables
+                // (and definitions created inside the body)
+                // are fully visible to other statements/expressions inside the body --Alex/Carl
                self.visit_body(body);
+
+                let break_states =
+                    std::mem::replace(&mut self.loop_break_states, saved_break_states);
+
+                // We may execute the `else` clause without ever executing the body, so merge in
+                // the pre-loop state before visiting `else`.
+                self.flow_merge(pre_loop);
                self.visit_body(orelse);
+
+                // Breaking out of a `for` loop bypasses the `else` clause, so merge in the break
+                // states after visiting `else`.
+                for break_state in break_states {
+                    self.flow_merge(break_state);
+                }
+            }
+            ast::Stmt::Match(ast::StmtMatch {
+                subject,
+                cases,
+                range: _,
+            }) => {
+                self.add_standalone_expression(subject);
+                self.visit_expr(subject);
+
+                let after_subject = self.flow_snapshot();
+                let Some((first, remaining)) = cases.split_first() else {
+                    return;
+                };
+                self.add_pattern_constraint(subject, &first.pattern);
+                self.visit_match_case(first);
+
+                let mut post_case_snapshots = vec![];
+                for case in remaining {
+                    post_case_snapshots.push(self.flow_snapshot());
+                    self.flow_restore(after_subject.clone());
+                    self.add_pattern_constraint(subject, &case.pattern);
+                    self.visit_match_case(case);
+                }
+                for post_clause_state in post_case_snapshots {
+                    self.flow_merge(post_clause_state);
+                }
+                if !cases
+                    .last()
+                    .is_some_and(|case| case.guard.is_none() && case.pattern.is_wildcard())
+                {
+                    self.flow_merge(after_subject);
+                }
+            }
+            ast::Stmt::Try(ast::StmtTry {
+                body,
+                handlers,
+                orelse,
+                finalbody,
+                is_star,
+                range: _,
+            }) => {
+                self.visit_body(body);
+
+                for except_handler in handlers {
+                    let ast::ExceptHandler::ExceptHandler(except_handler) = except_handler;
+                    let ast::ExceptHandlerExceptHandler {
+                        name: symbol_name,
+                        type_: handled_exceptions,
+                        body: handler_body,
+                        range: _,
+                    } = except_handler;
+
+                    if let Some(handled_exceptions) = handled_exceptions {
+                        self.visit_expr(handled_exceptions);
+                    }
+
+                    // If `handled_exceptions` above was `None`, it's something like `except as e:`,
+                    // which is invalid syntax. However, it's still pretty obvious here that the user
+                    // *wanted* `e` to be bound, so we should still create a definition here nonetheless.
+                    if let Some(symbol_name) = symbol_name {
+                        let symbol = self.add_symbol(symbol_name.id.clone());
+
+                        self.add_definition(
+                            symbol,
+                            DefinitionNodeRef::ExceptHandler(ExceptHandlerDefinitionNodeRef {
+                                handler: except_handler,
+                                is_star: *is_star,
+                            }),
+                        );
+                    }
+
+                    self.visit_body(handler_body);
+                }
+
+                self.visit_body(orelse);
+                self.visit_body(finalbody);
            }
            _ => {
                walk_stmt(self, stmt);
@@ -613,23 +802,18 @@ where

        match expr {
            ast::Expr::Name(name_node @ ast::ExprName { id, ctx, .. }) => {
-                let mut flags = match ctx {
-                    ast::ExprContext::Load => SymbolFlags::IS_USED,
-                    ast::ExprContext::Store => SymbolFlags::IS_DEFINED,
-                    ast::ExprContext::Del => SymbolFlags::IS_DEFINED,
-                    ast::ExprContext::Invalid => SymbolFlags::empty(),
+                let (is_use, is_definition) = match (ctx, self.current_assignment) {
+                    (ast::ExprContext::Store, Some(CurrentAssignment::AugAssign(_))) => {
+                        // For augmented assignment, the target expression is also used.
+                        (true, true)
+                    }
+                    (ast::ExprContext::Load, _) => (true, false),
+                    (ast::ExprContext::Store, _) => (false, true),
+                    (ast::ExprContext::Del, _) => (false, true),
+                    (ast::ExprContext::Invalid, _) => (false, false),
                };
-                if matches!(
-                    self.current_assignment,
-                    Some(CurrentAssignment::AugAssign(_))
-                ) && !ctx.is_invalid()
-                {
-                    // For augmented assignment, the target expression is also used, so we should
-                    // record that as a use.
-                    flags |= SymbolFlags::IS_USED;
-                }
-                let symbol = self.add_or_update_symbol(id.clone(), flags);
-                if flags.contains(SymbolFlags::IS_DEFINED) {
+                let symbol = self.add_symbol(id.clone());
+                if is_definition {
                    match self.current_assignment {
                        Some(CurrentAssignment::Assign(assignment)) => {
                            self.add_definition(
@@ -652,6 +836,7 @@ where
                                ForStmtDefinitionNodeRef {
                                    iterable: &node.iter,
                                    target: name_node,
+                                    is_async: node.is_async,
                                },
                            );
                        }
@@ -664,7 +849,12 @@ where
                        Some(CurrentAssignment::Comprehension { node, first }) => {
                            self.add_definition(
                                symbol,
-                                ComprehensionDefinitionNodeRef { node, first },
+                                ComprehensionDefinitionNodeRef {
+                                    iterable: &node.iter,
+                                    target: name_node,
+                                    first,
+                                    is_async: node.is_async,
+                                },
                            );
                        }
                        Some(CurrentAssignment::WithItem(with_item)) => {
@@ -680,7 +870,8 @@ where
                    }
                }

-                if flags.contains(SymbolFlags::IS_USED) {
+                if is_use {
+                    self.mark_symbol_used(symbol);
                    let use_id = self.current_ast_ids().record_use(expr);
                    self.current_use_def_map_mut().record_use(symbol, use_id);
                }
@@ -717,6 +908,7 @@ where
                }

                self.visit_expr(lambda.body.as_ref());
+                self.pop_scope();
            }
            ast::Expr::If(ast::ExprIf {
                body, test, orelse, ..
@@ -737,30 +929,33 @@ where
                    elt, generators, ..
                },
            ) => {
-                self.visit_generators(
+                self.with_generators_scope(
                    NodeWithScopeRef::ListComprehension(list_comprehension),
                    generators,
+                    |builder| builder.visit_expr(elt),
                );
-                self.visit_expr(elt);
            }
            ast::Expr::SetComp(
                set_comprehension @ ast::ExprSetComp {
                    elt, generators, ..
                },
            ) => {
-                self.visit_generators(
+                self.with_generators_scope(
                    NodeWithScopeRef::SetComprehension(set_comprehension),
                    generators,
+                    |builder| builder.visit_expr(elt),
                );
-                self.visit_expr(elt);
            }
            ast::Expr::Generator(
                generator @ ast::ExprGenerator {
                    elt, generators, ..
                },
            ) => {
-                self.visit_generators(NodeWithScopeRef::GeneratorExpression(generator), generators);
-                self.visit_expr(elt);
+                self.with_generators_scope(
+                    NodeWithScopeRef::GeneratorExpression(generator),
+                    generators,
+                    |builder| builder.visit_expr(elt),
+                );
            }
            ast::Expr::DictComp(
                dict_comprehension @ ast::ExprDictComp {
@@ -770,31 +965,22 @@ where
                    ..
                },
            ) => {
-                self.visit_generators(
+                self.with_generators_scope(
                    NodeWithScopeRef::DictComprehension(dict_comprehension),
                    generators,
+                    |builder| {
+                        builder.visit_expr(key);
+                        builder.visit_expr(value);
+                    },
                );
-                self.visit_expr(key);
-                self.visit_expr(value);
            }
            _ => {
                walk_expr(self, expr);
            }
        }
-
-        if matches!(
-            expr,
-            ast::Expr::Lambda(_)
-                | ast::Expr::ListComp(_)
-                | ast::Expr::SetComp(_)
-                | ast::Expr::Generator(_)
-                | ast::Expr::DictComp(_)
-        ) {
-            self.pop_scope();
-        }
    }

-    fn visit_parameters(&mut self, parameters: &'ast ruff_python_ast::Parameters) {
+    fn visit_parameters(&mut self, parameters: &'ast ast::Parameters) {
        // Intentionally avoid walking default expressions, as we handle them in the enclosing
        // scope.
        for parameter in parameters.iter().map(ast::AnyParameterRef::as_parameter) {
@@ -802,23 +988,58 @@ where
        }
    }

+    fn visit_match_case(&mut self, match_case: &'ast ast::MatchCase) {
+        debug_assert!(self.current_match_case.is_none());
+        self.current_match_case = Some(CurrentMatchCase::new(&match_case.pattern));
+        self.visit_pattern(&match_case.pattern);
+        self.current_match_case = None;
+
+        if let Some(expr) = &match_case.guard {
+            self.visit_expr(expr);
+        }
+        self.visit_body(&match_case.body);
+    }
+
    fn visit_pattern(&mut self, pattern: &'ast ast::Pattern) {
-        if let ast::Pattern::MatchAs(ast::PatternMatchAs {
-            name: Some(name), ..
-        })
-        | ast::Pattern::MatchStar(ast::PatternMatchStar {
+        if let ast::Pattern::MatchStar(ast::PatternMatchStar {
            name: Some(name),
            range: _,
+        }) = pattern
+        {
+            let symbol = self.add_symbol(name.id().clone());
+            let state = self.current_match_case.as_ref().unwrap();
+            self.add_definition(
+                symbol,
+                MatchPatternDefinitionNodeRef {
+                    pattern: state.pattern,
+                    identifier: name,
+                    index: state.index,
+                },
+            );
+        }
+
+        walk_pattern(self, pattern);
+
+        if let ast::Pattern::MatchAs(ast::PatternMatchAs {
+            name: Some(name), ..
        })
        | ast::Pattern::MatchMapping(ast::PatternMatchMapping {
            rest: Some(name), ..
        }) = pattern
        {
-            // TODO(dhruvmanila): Add definition
-            self.add_or_update_symbol(name.id.clone(), SymbolFlags::IS_DEFINED);
+            let symbol = self.add_symbol(name.id().clone());
+            let state = self.current_match_case.as_ref().unwrap();
+            self.add_definition(
+                symbol,
+                MatchPatternDefinitionNodeRef {
+                    pattern: state.pattern,
+                    identifier: name,
+                    index: state.index,
+                },
+            );
        }

-        walk_pattern(self, pattern);
+        self.current_match_case.as_mut().unwrap().index += 1;
    }
 }

@@ -871,3 +1092,27 @@ impl<'a> From<&'a ast::WithItem> for CurrentAssignment<'a> {
        Self::WithItem(value)
    }
 }
+
+struct CurrentMatchCase<'a> {
+    /// The pattern that's part of the current match case.
+    pattern: &'a ast::Pattern,
+
+    /// The index of the sub-pattern that's being currently visited within the pattern.
+    ///
+    /// For example:
+    /// ```py
+    /// match subject:
+    ///     case a as b: ...
+    ///     case [a, b]: ...
+    ///     case a | b: ...
+    /// ```
+    ///
+    /// In all of the above cases, the index would be 0 for `a` and 1 for `b`.
+    index: u32,
+}
+
+impl<'a> CurrentMatchCase<'a> {
+    fn new(pattern: &'a ast::Pattern) -> Self {
+        Self { pattern, index: 0 }
+    }
+}
--- a/crates/red_knot_python_semantic/src/semantic_index/constraint.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/constraint.rs
@@ -0,0 +1,39 @@
+use ruff_db::files::File;
+use ruff_python_ast as ast;
+
+use crate::ast_node_ref::AstNodeRef;
+use crate::db::Db;
+use crate::semantic_index::expression::Expression;
+use crate::semantic_index::symbol::{FileScopeId, ScopeId};
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub(crate) enum Constraint<'db> {
+    Expression(Expression<'db>),
+    Pattern(PatternConstraint<'db>),
+}
+
+#[salsa::tracked]
+pub(crate) struct PatternConstraint<'db> {
+    #[id]
+    pub(crate) file: File,
+
+    #[id]
+    pub(crate) file_scope: FileScopeId,
+
+    #[no_eq]
+    #[return_ref]
+    pub(crate) subject: AstNodeRef<ast::Expr>,
+
+    #[no_eq]
+    #[return_ref]
+    pub(crate) pattern: AstNodeRef<ast::Pattern>,
+
+    #[no_eq]
+    count: countme::Count<PatternConstraint<'static>>,
+}
+
+impl<'db> PatternConstraint<'db> {
+    pub(crate) fn scope(self, db: &'db dyn Db) -> ScopeId<'db> {
+        self.file_scope(db).to_scope_id(db, self.file(db))
+    }
+}
--- a/crates/red_knot_python_semantic/src/semantic_index/definition.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/definition.rs
@@ -23,7 +23,7 @@ pub struct Definition<'db> {

    #[no_eq]
    #[return_ref]
-    pub(crate) node: DefinitionKind,
+    pub(crate) kind: DefinitionKind,

    #[no_eq]
    count: countme::Count<Definition<'static>>,
@@ -33,6 +33,18 @@ impl<'db> Definition<'db> {
    pub(crate) fn scope(self, db: &'db dyn Db) -> ScopeId<'db> {
        self.file_scope(db).to_scope_id(db, self.file(db))
    }
+
+    pub(crate) fn category(self, db: &'db dyn Db) -> DefinitionCategory {
+        self.kind(db).category()
+    }
+
+    pub(crate) fn is_declaration(self, db: &'db dyn Db) -> bool {
+        self.kind(db).category().is_declaration()
+    }
+
+    pub(crate) fn is_binding(self, db: &'db dyn Db) -> bool {
+        self.kind(db).category().is_binding()
+    }
 }

 #[derive(Copy, Clone, Debug)]
@@ -49,6 +61,8 @@ pub(crate) enum DefinitionNodeRef<'a> {
    Comprehension(ComprehensionDefinitionNodeRef<'a>),
    Parameter(ast::AnyParameterRef<'a>),
    WithItem(WithItemDefinitionNodeRef<'a>),
+    MatchPattern(MatchPatternDefinitionNodeRef<'a>),
+    ExceptHandler(ExceptHandlerDefinitionNodeRef<'a>),
 }

 impl<'a> From<&'a ast::StmtFunctionDef> for DefinitionNodeRef<'a> {
@@ -123,6 +137,12 @@ impl<'a> From<ast::AnyParameterRef<'a>> for DefinitionNodeRef<'a> {
    }
 }

+impl<'a> From<MatchPatternDefinitionNodeRef<'a>> for DefinitionNodeRef<'a> {
+    fn from(node: MatchPatternDefinitionNodeRef<'a>) -> Self {
+        Self::MatchPattern(node)
+    }
+}
+
 #[derive(Copy, Clone, Debug)]
 pub(crate) struct ImportFromDefinitionNodeRef<'a> {
    pub(crate) node: &'a ast::StmtImportFrom,
@@ -145,12 +165,32 @@ pub(crate) struct WithItemDefinitionNodeRef<'a> {
 pub(crate) struct ForStmtDefinitionNodeRef<'a> {
    pub(crate) iterable: &'a ast::Expr,
    pub(crate) target: &'a ast::ExprName,
+    pub(crate) is_async: bool,
+}
+
+#[derive(Copy, Clone, Debug)]
+pub(crate) struct ExceptHandlerDefinitionNodeRef<'a> {
+    pub(crate) handler: &'a ast::ExceptHandlerExceptHandler,
+    pub(crate) is_star: bool,
 }

 #[derive(Copy, Clone, Debug)]
 pub(crate) struct ComprehensionDefinitionNodeRef<'a> {
-    pub(crate) node: &'a ast::Comprehension,
+    pub(crate) iterable: &'a ast::Expr,
+    pub(crate) target: &'a ast::ExprName,
    pub(crate) first: bool,
+    pub(crate) is_async: bool,
+}
+
+#[derive(Copy, Clone, Debug)]
+pub(crate) struct MatchPatternDefinitionNodeRef<'a> {
+    /// The outermost pattern node in which the identifier being defined occurs.
+    pub(crate) pattern: &'a ast::Pattern,
+    /// The identifier being defined.
+    pub(crate) identifier: &'a ast::Identifier,
+    /// The index of the identifier in the pattern when visiting the `pattern` node in evaluation
+    /// order.
+    pub(crate) index: u32,
 }

 impl DefinitionNodeRef<'_> {
@@ -187,18 +227,26 @@ impl DefinitionNodeRef<'_> {
            DefinitionNodeRef::AugmentedAssignment(augmented_assignment) => {
                DefinitionKind::AugmentedAssignment(AstNodeRef::new(parsed, augmented_assignment))
            }
-            DefinitionNodeRef::For(ForStmtDefinitionNodeRef { iterable, target }) => {
-                DefinitionKind::For(ForStmtDefinitionKind {
-                    iterable: AstNodeRef::new(parsed.clone(), iterable),
-                    target: AstNodeRef::new(parsed, target),
-                })
-            }
-            DefinitionNodeRef::Comprehension(ComprehensionDefinitionNodeRef { node, first }) => {
-                DefinitionKind::Comprehension(ComprehensionDefinitionKind {
-                    node: AstNodeRef::new(parsed, node),
-                    first,
-                })
-            }
+            DefinitionNodeRef::For(ForStmtDefinitionNodeRef {
+                iterable,
+                target,
+                is_async,
+            }) => DefinitionKind::For(ForStmtDefinitionKind {
+                iterable: AstNodeRef::new(parsed.clone(), iterable),
+                target: AstNodeRef::new(parsed, target),
+                is_async,
+            }),
+            DefinitionNodeRef::Comprehension(ComprehensionDefinitionNodeRef {
+                iterable,
+                target,
+                first,
+                is_async,
+            }) => DefinitionKind::Comprehension(ComprehensionDefinitionKind {
+                iterable: AstNodeRef::new(parsed.clone(), iterable),
+                target: AstNodeRef::new(parsed, target),
+                first,
+                is_async,
+            }),
            DefinitionNodeRef::Parameter(parameter) => match parameter {
                ast::AnyParameterRef::Variadic(parameter) => {
                    DefinitionKind::Parameter(AstNodeRef::new(parsed, parameter))
@@ -213,6 +261,22 @@ impl DefinitionNodeRef<'_> {
                    target: AstNodeRef::new(parsed, target),
                })
            }
+            DefinitionNodeRef::MatchPattern(MatchPatternDefinitionNodeRef {
+                pattern,
+                identifier,
+                index,
+            }) => DefinitionKind::MatchPattern(MatchPatternDefinitionKind {
+                pattern: AstNodeRef::new(parsed.clone(), pattern),
+                identifier: AstNodeRef::new(parsed, identifier),
+                index,
+            }),
+            DefinitionNodeRef::ExceptHandler(ExceptHandlerDefinitionNodeRef {
+                handler,
+                is_star,
+            }) => DefinitionKind::ExceptHandler(ExceptHandlerDefinitionKind {
+                handler: AstNodeRef::new(parsed.clone(), handler),
+                is_star,
+            }),
        }
    }

@@ -234,17 +298,57 @@ impl DefinitionNodeRef<'_> {
            Self::For(ForStmtDefinitionNodeRef {
                iterable: _,
                target,
+                is_async: _,
            }) => target.into(),
-            Self::Comprehension(ComprehensionDefinitionNodeRef { node, first: _ }) => node.into(),
+            Self::Comprehension(ComprehensionDefinitionNodeRef { target, .. }) => target.into(),
            Self::Parameter(node) => match node {
                ast::AnyParameterRef::Variadic(parameter) => parameter.into(),
                ast::AnyParameterRef::NonVariadic(parameter) => parameter.into(),
            },
            Self::WithItem(WithItemDefinitionNodeRef { node: _, target }) => target.into(),
+            Self::MatchPattern(MatchPatternDefinitionNodeRef { identifier, .. }) => {
+                identifier.into()
+            }
+            Self::ExceptHandler(ExceptHandlerDefinitionNodeRef { handler, .. }) => handler.into(),
        }
    }
 }

+#[derive(Clone, Copy, Debug)]
+pub(crate) enum DefinitionCategory {
+    /// A Definition which binds a value to a name (e.g. `x = 1`).
+    Binding,
+    /// A Definition which declares the upper-bound of acceptable types for this name (`x: int`).
+    Declaration,
+    /// A Definition which both declares a type and binds a value (e.g. `x: int = 1`).
+    DeclarationAndBinding,
+}
+
+impl DefinitionCategory {
+    /// True if this definition establishes a "declared type" for the symbol.
+    ///
+    /// If so, any assignments reached by this definition are in error if they assign a value of a
+    /// type not assignable to the declared type.
+    ///
+    /// Annotations establish a declared type. So do function and class definitions, and imports.
+    pub(crate) fn is_declaration(self) -> bool {
+        matches!(
+            self,
+            DefinitionCategory::Declaration | DefinitionCategory::DeclarationAndBinding
+        )
+    }
+
+    /// True if this definition assigns a value to the symbol.
+    ///
+    /// False only for annotated assignments without a RHS.
+    pub(crate) fn is_binding(self) -> bool {
+        matches!(
+            self,
+            DefinitionCategory::Binding | DefinitionCategory::DeclarationAndBinding
+        )
+    }
+}
+
 #[derive(Clone, Debug)]
 pub enum DefinitionKind {
    Import(AstNodeRef<ast::Alias>),
@@ -260,22 +364,97 @@ pub enum DefinitionKind {
    Parameter(AstNodeRef<ast::Parameter>),
    ParameterWithDefault(AstNodeRef<ast::ParameterWithDefault>),
    WithItem(WithItemDefinitionKind),
+    MatchPattern(MatchPatternDefinitionKind),
+    ExceptHandler(ExceptHandlerDefinitionKind),
+}
+
+impl DefinitionKind {
+    pub(crate) fn category(&self) -> DefinitionCategory {
+        match self {
+            // functions, classes, and imports always bind, and we consider them declarations
+            DefinitionKind::Function(_)
+            | DefinitionKind::Class(_)
+            | DefinitionKind::Import(_)
+            | DefinitionKind::ImportFrom(_) => DefinitionCategory::DeclarationAndBinding,
+            // a parameter always binds a value, but is only a declaration if annotated
+            DefinitionKind::Parameter(parameter) => {
+                if parameter.annotation.is_some() {
+                    DefinitionCategory::DeclarationAndBinding
+                } else {
+                    DefinitionCategory::Binding
+                }
+            }
+            // presence of a default is irrelevant, same logic as for a no-default parameter
+            DefinitionKind::ParameterWithDefault(parameter_with_default) => {
+                if parameter_with_default.parameter.annotation.is_some() {
+                    DefinitionCategory::DeclarationAndBinding
+                } else {
+                    DefinitionCategory::Binding
+                }
+            }
+            // annotated assignment is always a declaration, only a binding if there is a RHS
+            DefinitionKind::AnnotatedAssignment(ann_assign) => {
+                if ann_assign.value.is_some() {
+                    DefinitionCategory::DeclarationAndBinding
+                } else {
+                    DefinitionCategory::Declaration
+                }
+            }
+            // all of these bind values without declaring a type
+            DefinitionKind::NamedExpression(_)
+            | DefinitionKind::Assignment(_)
+            | DefinitionKind::AugmentedAssignment(_)
+            | DefinitionKind::For(_)
+            | DefinitionKind::Comprehension(_)
+            | DefinitionKind::WithItem(_)
+            | DefinitionKind::MatchPattern(_)
+            | DefinitionKind::ExceptHandler(_) => DefinitionCategory::Binding,
+        }
+    }
+}
+
+#[derive(Clone, Debug)]
+#[allow(dead_code)]
+pub struct MatchPatternDefinitionKind {
+    pattern: AstNodeRef<ast::Pattern>,
+    identifier: AstNodeRef<ast::Identifier>,
+    index: u32,
+}
+
+impl MatchPatternDefinitionKind {
+    pub(crate) fn pattern(&self) -> &ast::Pattern {
+        self.pattern.node()
+    }
+
+    pub(crate) fn index(&self) -> u32 {
+        self.index
+    }
 }

 #[derive(Clone, Debug)]
 pub struct ComprehensionDefinitionKind {
-    node: AstNodeRef<ast::Comprehension>,
+    iterable: AstNodeRef<ast::Expr>,
+    target: AstNodeRef<ast::ExprName>,
    first: bool,
+    is_async: bool,
 }

 impl ComprehensionDefinitionKind {
-    pub(crate) fn node(&self) -> &ast::Comprehension {
-        self.node.node()
+    pub(crate) fn iterable(&self) -> &ast::Expr {
+        self.iterable.node()
+    }
+
+    pub(crate) fn target(&self) -> &ast::ExprName {
+        self.target.node()
    }

    pub(crate) fn is_first(&self) -> bool {
        self.first
    }
+
+    pub(crate) fn is_async(&self) -> bool {
+        self.is_async
+    }
 }

 #[derive(Clone, Debug)]
@@ -330,6 +509,7 @@ impl WithItemDefinitionKind {
 pub struct ForStmtDefinitionKind {
    iterable: AstNodeRef<ast::Expr>,
    target: AstNodeRef<ast::ExprName>,
+    is_async: bool,
 }

 impl ForStmtDefinitionKind {
@@ -340,6 +520,30 @@ impl ForStmtDefinitionKind {
    pub(crate) fn target(&self) -> &ast::ExprName {
        self.target.node()
    }
+
+    pub(crate) fn is_async(&self) -> bool {
+        self.is_async
+    }
+}
+
+#[derive(Clone, Debug)]
+pub struct ExceptHandlerDefinitionKind {
+    handler: AstNodeRef<ast::ExceptHandlerExceptHandler>,
+    is_star: bool,
+}
+
+impl ExceptHandlerDefinitionKind {
+    pub(crate) fn node(&self) -> &ast::ExceptHandlerExceptHandler {
+        self.handler.node()
+    }
+
+    pub(crate) fn handled_exceptions(&self) -> Option<&ast::Expr> {
+        self.node().type_.as_deref()
+    }
+
+    pub(crate) fn is_star(&self) -> bool {
+        self.is_star
+    }
 }

 #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
@@ -393,12 +597,6 @@ impl From<&ast::StmtFor> for DefinitionNodeKey {
    }
 }

-impl From<&ast::Comprehension> for DefinitionNodeKey {
-    fn from(node: &ast::Comprehension) -> Self {
-        Self(NodeKey::from_node(node))
-    }
-}
-
 impl From<&ast::Parameter> for DefinitionNodeKey {
    fn from(node: &ast::Parameter) -> Self {
        Self(NodeKey::from_node(node))
@@ -410,3 +608,15 @@ impl From<&ast::ParameterWithDefault> for DefinitionNodeKey {
        Self(NodeKey::from_node(node))
    }
 }
+
+impl From<&ast::Identifier> for DefinitionNodeKey {
+    fn from(identifier: &ast::Identifier) -> Self {
+        Self(NodeKey::from_node(identifier))
+    }
+}
+
+impl From<&ast::ExceptHandlerExceptHandler> for DefinitionNodeKey {
+    fn from(handler: &ast::ExceptHandlerExceptHandler) -> Self {
+        Self(NodeKey::from_node(handler))
+    }
+}
--- a/crates/red_knot_python_semantic/src/semantic_index/symbol.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/symbol.rs
@@ -44,16 +44,16 @@ impl Symbol {
    }

    /// Is the symbol defined in its containing scope?
-    pub fn is_defined(&self) -> bool {
-        self.flags.contains(SymbolFlags::IS_DEFINED)
+    pub fn is_bound(&self) -> bool {
+        self.flags.contains(SymbolFlags::IS_BOUND)
    }
 }

 bitflags! {
    #[derive(Copy, Clone, Debug, Eq, PartialEq)]
-    pub(super) struct SymbolFlags: u8 {
+    struct SymbolFlags: u8 {
        const IS_USED         = 1 << 0;
-        const IS_DEFINED      = 1 << 1;
+        const IS_BOUND      = 1 << 1;
        /// TODO: This flag is not yet set by anything
        const MARKED_GLOBAL   = 1 << 2;
        /// TODO: This flag is not yet set by anything
@@ -149,6 +149,10 @@ impl FileScopeId {
        FileScopeId::from_u32(0)
    }

+    pub fn is_global(self) -> bool {
+        self == FileScopeId::global()
+    }
+
    pub fn to_scope_id(self, db: &dyn Db, file: File) -> ScopeId<'_> {
        let index = semantic_index(db, file);
        index.scope_ids_by_scope[self]
@@ -268,11 +272,7 @@ impl SymbolTableBuilder {
        }
    }

-    pub(super) fn add_or_update_symbol(
-        &mut self,
-        name: Name,
-        flags: SymbolFlags,
-    ) -> (ScopedSymbolId, bool) {
+    pub(super) fn add_symbol(&mut self, name: Name) -> (ScopedSymbolId, bool) {
        let hash = SymbolTable::hash_name(&name);
        let entry = self
            .table
@@ -281,15 +281,9 @@ impl SymbolTableBuilder {
            .from_hash(hash, |id| self.table.symbols[*id].name() == &name);

        match entry {
-            RawEntryMut::Occupied(entry) => {
-                let symbol = &mut self.table.symbols[*entry.key()];
-                symbol.insert_flags(flags);
-
-                (*entry.key(), false)
-            }
+            RawEntryMut::Occupied(entry) => (*entry.key(), false),
            RawEntryMut::Vacant(entry) => {
-                let mut symbol = Symbol::new(name);
-                symbol.insert_flags(flags);
+                let symbol = Symbol::new(name);

                let id = self.table.symbols.push(symbol);
                entry.insert_with_hasher(hash, id, (), |id| {
@@ -300,6 +294,14 @@ impl SymbolTableBuilder {
        }
    }

+    pub(super) fn mark_symbol_bound(&mut self, id: ScopedSymbolId) {
+        self.table.symbols[id].insert_flags(SymbolFlags::IS_BOUND);
+    }
+
+    pub(super) fn mark_symbol_used(&mut self, id: ScopedSymbolId) {
+        self.table.symbols[id].insert_flags(SymbolFlags::IS_USED);
+    }
+
    pub(super) fn finish(mut self) -> SymbolTable {
        self.table.shrink_to_fit();
        self.table
--- a/crates/red_knot_python_semantic/src/semantic_index/use_def.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/use_def.rs
@@ -1,5 +1,79 @@
-//! Build a map from each use of a symbol to the definitions visible from that use, and the
-//! type-narrowing constraints that apply to each definition.
+//! First, some terminology:
+//!
+//! * A "binding" gives a new value to a variable. This includes many different Python statements
+//!   (assignment statements of course, but also imports, `def` and `class` statements, `as`
+//!   clauses in `with` and `except` statements, match patterns, and others) and even one
+//!   expression kind (named expressions). It notably does not include annotated assignment
+//!   statements without a right-hand side value; these do not assign any new value to the
+//!   variable. We consider function parameters to be bindings as well, since (from the perspective
+//!   of the function's internal scope), a function parameter begins the scope bound to a value.
+//!
+//! * A "declaration" establishes an upper bound type for the values that a variable may be
+//!   permitted to take on. Annotated assignment statements (with or without an RHS value) are
+//!   declarations; annotated function parameters are also declarations. We consider `def` and
+//!   `class` statements to also be declarations, so as to prohibit accidentally shadowing them.
+//!
+//! Annotated assignments with a right-hand side, and annotated function parameters, are both
+//! bindings and declarations.
+//!
+//! We use [`Definition`] as the universal term (and Salsa tracked struct) encompassing both
+//! bindings and declarations. (This sacrifices a bit of type safety in exchange for improved
+//! performance via fewer Salsa tracked structs and queries, since most declarations -- typed
+//! parameters and annotated assignments with RHS -- are both bindings and declarations.)
+//!
+//! At any given use of a variable, we can ask about both its "declared type" and its "inferred
+//! type". These may be different, but the inferred type must always be assignable to the declared
+//! type; that is, the declared type is always wider, and the inferred type may be more precise. If
+//! we see an invalid assignment, we emit a diagnostic and abandon our inferred type, deferring to
+//! the declared type (this allows an explicit annotation to override bad inference, without a
+//! cast), maintaining the invariant.
+//!
+//! The **inferred type** represents the most precise type we believe encompasses all possible
+//! values for the variable at a given use. It is based on a union of the bindings which can reach
+//! that use through some control flow path, and the narrowing constraints that control flow must
+//! have passed through between the binding and the use. For example, in this code:
+//!
+//! ```python
+//! x = 1 if flag else None
+//! if x is not None:
+//!     use(x)
+//! ```
+//!
+//! For the use of `x` on the third line, the inferred type should be `Literal[1]`. This is based
+//! on the binding on the first line, which assigns the type `Literal[1] | None`, and the narrowing
+//! constraint on the second line, which rules out the type `None`, since control flow must pass
+//! through this constraint to reach the use in question.
+//!
+//! The **declared type** represents the code author's declaration (usually through a type
+//! annotation) that a given variable should not be assigned any type outside the declared type. In
+//! our model, declared types are also control-flow-sensitive; we allow the code author to
+//! explicitly re-declare the same variable with a different type. So for a given binding of a
+//! variable, we will want to ask which declarations of that variable can reach that binding, in
+//! order to determine whether the binding is permitted, or should be a type error. For example:
+//!
+//! ```python
+//! from pathlib import Path
+//! def f(path: str):
+//!     path: Path = Path(path)
+//! ```
+//!
+//! In this function, the initial declared type of `path` is `str`, meaning that the assignment
+//! `path = Path(path)` would be a type error, since it assigns to `path` a value whose type is not
+//! assignable to `str`. This is the purpose of declared types: they prevent accidental assignment
+//! of the wrong type to a variable.
+//!
+//! But in some cases it is useful to "shadow" or "re-declare" a variable with a new type, and we
+//! permit this, as long as it is done with an explicit re-annotation. So `path: Path =
+//! Path(path)`, with the explicit `: Path` annotation, is permitted.
+//!
+//! The general rule is that whatever declaration(s) can reach a given binding determine the
+//! validity of that binding. If there is a path in which the symbol is not declared, that is a
+//! declaration of `Unknown`. If multiple declarations can reach a binding, we union them, but by
+//! default we also issue a type error, since this implicit union of declared types may hide an
+//! error.
+//!
+//! To support type inference, we build a map from each use of a symbol to the bindings live at
+//! that use, and the type narrowing constraints that apply to each binding.
 //!
 //! Let's take this code sample:
 //!
@@ -7,148 +81,157 @@
 //! x = 1
 //! x = 2
 //! y = x
-//! if y is not None:
+//! if flag:
 //!     x = 3
 //! else:
 //!     x = 4
 //! z = x
 //! ```
 //!
-//! In this snippet, we have four definitions of `x` (the statements assigning `1`, `2`, `3`,
-//! and `4` to it), and two uses of `x` (the `y = x` and `z = x` assignments). The first
-//! [`Definition`] of `x` is never visible to any use, because it's immediately replaced by the
-//! second definition, before any use happens. (A linter could thus flag the statement `x = 1`
-//! as likely superfluous.)
+//! In this snippet, we have four bindings of `x` (the statements assigning `1`, `2`, `3`, and `4`
+//! to it), and two uses of `x` (the `y = x` and `z = x` assignments). The first binding of `x`
+//! does not reach any use, because it's immediately replaced by the second binding, before any use
+//! happens. (A linter could thus flag the statement `x = 1` as likely superfluous.)
 //!
-//! The first use of `x` has one definition visible to it: the assignment `x = 2`.
+//! The first use of `x` has one live binding: the assignment `x = 2`.
 //!
 //! Things get a bit more complex when we have branches. We will definitely take either the `if` or
-//! the `else` branch. Thus, the second use of `x` has two definitions visible to it: `x = 3` and
-//! `x = 4`. The `x = 2` definition is no longer visible, because it must be replaced by either `x
-//! = 3` or `x = 4`, no matter which branch was taken. We don't know which branch was taken, so we
-//! must consider both definitions as visible, which means eventually we would (in type inference)
-//! look at these two definitions and infer a type of `Literal[3, 4]` -- the union of `Literal[3]`
-//! and `Literal[4]` -- for the second use of `x`.
+//! the `else` branch. Thus, the second use of `x` has two live bindings: `x = 3` and `x = 4`. The
+//! `x = 2` assignment is no longer visible, because it must be replaced by either `x = 3` or `x =
+//! 4`, no matter which branch was taken. We don't know which branch was taken, so we must consider
+//! both bindings as live, which means eventually we would (in type inference) look at these two
+//! bindings and infer a type of `Literal[3, 4]` -- the union of `Literal[3]` and `Literal[4]` --
+//! for the second use of `x`.
 //!
 //! So that's one question our use-def map needs to answer: given a specific use of a symbol, which
-//! definition(s) is/are visible from that use. In
-//! [`AstIds`](crate::semantic_index::ast_ids::AstIds) we number all uses (that means a `Name` node
-//! with `Load` context) so we have a `ScopedUseId` to efficiently represent each use.
+//! binding(s) can reach that use. In [`AstIds`](crate::semantic_index::ast_ids::AstIds) we number
+//! all uses (that means a `Name` node with `Load` context) so we have a `ScopedUseId` to
+//! efficiently represent each use.
 //!
-//! Another case we need to handle is when a symbol is referenced from a different scope (the most
-//! obvious example of this is an import). We call this "public" use of a symbol. So the other
-//! question we need to be able to answer is, what are the publicly-visible definitions of each
-//! symbol?
-//!
-//! Technically, public use of a symbol could also occur from any point in control flow of the
-//! scope where the symbol is defined (via inline imports and import cycles, in the case of an
-//! import, or via a function call partway through the local scope that ends up using a symbol from
-//! the scope via a global or nonlocal reference.) But modeling this fully accurately requires
-//! whole-program analysis that isn't tractable for an efficient incremental compiler, since it
-//! means a given symbol could have a different type every place it's referenced throughout the
-//! program, depending on the shape of arbitrarily-sized call/import graphs. So we follow other
-//! Python type-checkers in making the simplifying assumption that usually the scope will finish
-//! execution before its symbols are made visible to other scopes; for instance, most imports will
-//! import from a complete module, not a partially-executed module. (We may want to get a little
-//! smarter than this in the future, in particular for closures, but for now this is where we
-//! start.)
-//!
-//! So this means that the publicly-visible definitions of a symbol are the definitions still
-//! visible at the end of the scope; effectively we have an implicit "use" of every symbol at the
-//! end of the scope.
-//!
-//! We also need to know, for a given definition of a symbol, what type-narrowing constraints apply
+//! We also need to know, for a given definition of a symbol, what type narrowing constraints apply
 //! to it. For instance, in this code sample:
 //!
 //! ```python
 //! x = 1 if flag else None
 //! if x is not None:
-//!     y = x
+//!     use(x)
 //! ```
 //!
-//! At the use of `x` in `y = x`, the visible definition of `x` is `1 if flag else None`, which
-//! would infer as the type `Literal[1] | None`. But the constraint `x is not None` dominates this
-//! use, which means we can rule out the possibility that `x` is `None` here, which should give us
-//! the type `Literal[1]` for this use.
+//! At the use of `x`, the live binding of `x` is `1 if flag else None`, which would infer as the
+//! type `Literal[1] | None`. But the constraint `x is not None` dominates this use, which means we
+//! can rule out the possibility that `x` is `None` here, which should give us the type
+//! `Literal[1]` for this use.
+//!
+//! For declared types, we need to be able to answer the question "given a binding to a symbol,
+//! which declarations of that symbol can reach the binding?" This allows us to emit a diagnostic
+//! if the binding is attempting to bind a value of a type that is not assignable to the declared
+//! type for that symbol, at that point in control flow.
+//!
+//! We also need to know, given a declaration of a symbol, what the inferred type of that symbol is
+//! at that point. This allows us to emit a diagnostic in a case like `x = "foo"; x: int`. The
+//! binding `x = "foo"` occurs before the declaration `x: int`, so according to our
+//! control-flow-sensitive interpretation of declarations, the assignment is not an error. But the
+//! declaration is an error, since it would violate the "inferred type must be assignable to
+//! declared type" rule.
+//!
+//! Another case we need to handle is when a symbol is referenced from a different scope (for
+//! example, an import or a nonlocal reference). We call this "public" use of a symbol. For public
+//! use of a symbol, we prefer the declared type, if there are any declarations of that symbol; if
+//! not, we fall back to the inferred type. So we also need to know which declarations and bindings
+//! can reach the end of the scope.
+//!
+//! Technically, public use of a symbol could occur from any point in control flow of the scope
+//! where the symbol is defined (via inline imports and import cycles, in the case of an import, or
+//! via a function call partway through the local scope that ends up using a symbol from the scope
+//! via a global or nonlocal reference.) But modeling this fully accurately requires whole-program
+//! analysis that isn't tractable for an efficient analysis, since it means a given symbol could
+//! have a different type every place it's referenced throughout the program, depending on the
+//! shape of arbitrarily-sized call/import graphs. So we follow other Python type checkers in
+//! making the simplifying assumption that usually the scope will finish execution before its
+//! symbols are made visible to other scopes; for instance, most imports will import from a
+//! complete module, not a partially-executed module. (We may want to get a little smarter than
+//! this in the future for some closures, but for now this is where we start.)
 //!
 //! The data structure we build to answer these questions is the `UseDefMap`. It has a
-//! `definitions_by_use` vector indexed by [`ScopedUseId`] and a `public_definitions` vector
-//! indexed by [`ScopedSymbolId`]. The values in each of these vectors are (in principle) a list of
-//! visible definitions at that use, or at the end of the scope for that symbol, with a list of the
-//! dominating constraints for each of those definitions.
+//! `bindings_by_use` vector of [`SymbolBindings`] indexed by [`ScopedUseId`], a
+//! `declarations_by_binding` vector of [`SymbolDeclarations`] indexed by [`ScopedDefinitionId`], a
+//! `bindings_by_declaration` vector of [`SymbolBindings`] indexed by [`ScopedDefinitionId`], and
+//! `public_bindings` and `public_definitions` vectors indexed by [`ScopedSymbolId`]. The values in
+//! each of these vectors are (in principle) a list of live bindings at that use/definition, or at
+//! the end of the scope for that symbol, with a list of the dominating constraints for each
+//! binding.
 //!
 //! In order to avoid vectors-of-vectors-of-vectors and all the allocations that would entail, we
 //! don't actually store these "list of visible definitions" as a vector of [`Definition`].
-//! Instead, the values in `definitions_by_use` and `public_definitions` are a [`SymbolState`]
-//! struct which uses bit-sets to track definitions and constraints in terms of
-//! [`ScopedDefinitionId`] and [`ScopedConstraintId`], which are indices into the `all_definitions`
-//! and `all_constraints` indexvecs in the [`UseDefMap`].
+//! Instead, [`SymbolBindings`] and [`SymbolDeclarations`] are structs which use bit-sets to track
+//! definitions (and constraints, in the case of bindings) in terms of [`ScopedDefinitionId`] and
+//! [`ScopedConstraintId`], which are indices into the `all_definitions` and `all_constraints`
+//! indexvecs in the [`UseDefMap`].
 //!
 //! There is another special kind of possible "definition" for a symbol: there might be a path from
 //! the scope entry to a given use in which the symbol is never bound.
 //!
-//! The simplest way to model "unbound" would be as an actual [`Definition`] itself: the initial
-//! visible [`Definition`] for each symbol in a scope. But actually modeling it this way would
-//! unnecessarily increase the number of [`Definition`] that Salsa must track. Since "unbound" is a
-//! special definition in that all symbols share it, and it doesn't have any additional per-symbol
-//! state, and constraints are irrelevant to it, we can represent it more efficiently: we use the
-//! `may_be_unbound` boolean on the [`SymbolState`] struct. If this flag is `true`, it means the
-//! symbol/use really has one additional visible "definition", which is the unbound state. If this
-//! flag is `false`, it means we've eliminated the possibility of unbound: every path we've
-//! followed includes a definition for this symbol.
+//! The simplest way to model "unbound" would be as a "binding" itself: the initial "binding" for
+//! each symbol in a scope. But actually modeling it this way would unnecessarily increase the
+//! number of [`Definition`]s that Salsa must track. Since "unbound" is special in that all symbols
+//! share it, and it doesn't have any additional per-symbol state, and constraints are irrelevant
+//! to it, we can represent it more efficiently: we use the `may_be_unbound` boolean on the
+//! [`SymbolBindings`] struct. If this flag is `true` for a use of a symbol, it means the symbol
+//! has a path to the use in which it is never bound. If this flag is `false`, it means we've
+//! eliminated the possibility of unbound: every control flow path to the use includes a binding
+//! for this symbol.
 //!
 //! To build a [`UseDefMap`], the [`UseDefMapBuilder`] is notified of each new use, definition, and
 //! constraint as they are encountered by the
 //! [`SemanticIndexBuilder`](crate::semantic_index::builder::SemanticIndexBuilder) AST visit. For
-//! each symbol, the builder tracks the `SymbolState` for that symbol. When we hit a use of a
-//! symbol, it records the current state for that symbol for that use. When we reach the end of the
-//! scope, it records the state for each symbol as the public definitions of that symbol.
+//! each symbol, the builder tracks the `SymbolState` (`SymbolBindings` and `SymbolDeclarations`)
+//! for that symbol. When we hit a use or definition of a symbol, we record the necessary parts of
+//! the current state for that symbol that we need for that use or definition. When we reach the
+//! end of the scope, it records the state for each symbol as the public definitions of that
+//! symbol.
 //!
-//! Let's walk through the above example. Initially we record for `x` that it has no visible
-//! definitions, and may be unbound. When we see `x = 1`, we record that as the sole visible
-//! definition of `x`, and flip `may_be_unbound` to `false`. Then we see `x = 2`, and it replaces
-//! `x = 1` as the sole visible definition of `x`. When we get to `y = x`, we record that the
-//! visible definitions for that use of `x` are just the `x = 2` definition.
+//! Let's walk through the above example. Initially we record for `x` that it has no bindings, and
+//! may be unbound. When we see `x = 1`, we record that as the sole live binding of `x`, and flip
+//! `may_be_unbound` to `false`. Then we see `x = 2`, and we replace `x = 1` as the sole live
+//! binding of `x`. When we get to `y = x`, we record that the live bindings for that use of `x`
+//! are just the `x = 2` definition.
 //!
 //! Then we hit the `if` branch. We visit the `test` node (`flag` in this case), since that will
-//! happen regardless. Then we take a pre-branch snapshot of the currently visible definitions for
-//! all symbols, which we'll need later. Then we record `flag` as a possible constraint on the
-//! currently visible definition (`x = 2`), and go ahead and visit the `if` body. When we see `x =
-//! 3`, it replaces `x = 2` (constrained by `flag`) as the sole visible definition of `x`. At the
-//! end of the `if` body, we take another snapshot of the currently-visible definitions; we'll call
-//! this the post-if-body snapshot.
+//! happen regardless. Then we take a pre-branch snapshot of the current state for all symbols,
+//! which we'll need later. Then we record `flag` as a possible constraint on the current binding
+//! (`x = 2`), and go ahead and visit the `if` body. When we see `x = 3`, it replaces `x = 2`
+//! (constrained by `flag`) as the sole live binding of `x`. At the end of the `if` body, we take
+//! another snapshot of the current symbol state; we'll call this the post-if-body snapshot.
 //!
 //! Now we need to visit the `else` clause. The conditions when entering the `else` clause should
 //! be the pre-if conditions; if we are entering the `else` clause, we know that the `if` test
 //! failed and we didn't execute the `if` body. So we first reset the builder to the pre-if state,
-//! using the snapshot we took previously (meaning we now have `x = 2` as the sole visible
-//! definition for `x` again), then visit the `else` clause, where `x = 4` replaces `x = 2` as the
-//! sole visible definition of `x`.
+//! using the snapshot we took previously (meaning we now have `x = 2` as the sole binding for `x`
+//! again), then visit the `else` clause, where `x = 4` replaces `x = 2` as the sole live binding
+//! of `x`.
 //!
 //! Now we reach the end of the if/else, and want to visit the following code. The state here needs
 //! to reflect that we might have gone through the `if` branch, or we might have gone through the
 //! `else` branch, and we don't know which. So we need to "merge" our current builder state
-//! (reflecting the end-of-else state, with `x = 4` as the only visible definition) with our
-//! post-if-body snapshot (which has `x = 3` as the only visible definition). The result of this
-//! merge is that we now have two visible definitions of `x`: `x = 3` and `x = 4`.
+//! (reflecting the end-of-else state, with `x = 4` as the only live binding) with our post-if-body
+//! snapshot (which has `x = 3` as the only live binding). The result of this merge is that we now
+//! have two live bindings of `x`: `x = 3` and `x = 4`.
 //!
 //! The [`UseDefMapBuilder`] itself just exposes methods for taking a snapshot, resetting to a
 //! snapshot, and merging a snapshot into the current state. The logic using these methods lives in
 //! [`SemanticIndexBuilder`](crate::semantic_index::builder::SemanticIndexBuilder), e.g. where it
 //! visits a `StmtIf` node.
-//!
-//! (In the future we may have some other questions we want to answer as well, such as "is this
-//! definition used?", which will require tracking a bit more info in our map, e.g. a "used" bit
-//! for each [`Definition`] which is flipped to true when we record that definition for a use.)
 use self::symbol_state::{
-    ConstraintIdIterator, DefinitionIdWithConstraintsIterator, ScopedConstraintId,
-    ScopedDefinitionId, SymbolState,
+    BindingIdWithConstraintsIterator, ConstraintIdIterator, DeclarationIdIterator,
+    ScopedConstraintId, ScopedDefinitionId, SymbolBindings, SymbolDeclarations, SymbolState,
 };
 use crate::semantic_index::ast_ids::ScopedUseId;
 use crate::semantic_index::definition::Definition;
-use crate::semantic_index::expression::Expression;
 use crate::semantic_index::symbol::ScopedSymbolId;
 use ruff_index::IndexVec;
+use rustc_hash::FxHashMap;
+
+use super::constraint::Constraint;

 mod bitset;
 mod symbol_state;
@@ -159,63 +242,135 @@ pub(crate) struct UseDefMap<'db> {
    /// Array of [`Definition`] in this scope.
    all_definitions: IndexVec<ScopedDefinitionId, Definition<'db>>,

-    /// Array of constraints (as [`Expression`]) in this scope.
-    all_constraints: IndexVec<ScopedConstraintId, Expression<'db>>,
+    /// Array of [`Constraint`] in this scope.
+    all_constraints: IndexVec<ScopedConstraintId, Constraint<'db>>,

-    /// [`SymbolState`] visible at a [`ScopedUseId`].
-    definitions_by_use: IndexVec<ScopedUseId, SymbolState>,
+    /// [`SymbolBindings`] reaching a [`ScopedUseId`].
+    bindings_by_use: IndexVec<ScopedUseId, SymbolBindings>,
+
+    /// [`SymbolBindings`] or [`SymbolDeclarations`] reaching a given [`Definition`].
+    ///
+    /// If the definition is a binding (only) -- `x = 1` for example -- then we need
+    /// [`SymbolDeclarations`] to know whether this binding is permitted by the live declarations.
+    ///
+    /// If the definition is a declaration (only) -- `x: int` for example -- then we need
+    /// [`SymbolBindings`] to know whether this declaration is consistent with the previously
+    /// inferred type.
+    ///
+    /// If the definition is both a declaration and a binding -- `x: int = 1` for example -- then
+    /// we don't actually need anything here, all we'll need to validate is that our own RHS is a
+    /// valid assignment to our own annotation.
+    definitions_by_definition: FxHashMap<Definition<'db>, SymbolDefinitions>,

    /// [`SymbolState`] visible at end of scope for each symbol.
-    public_definitions: IndexVec<ScopedSymbolId, SymbolState>,
+    public_symbols: IndexVec<ScopedSymbolId, SymbolState>,
 }

 impl<'db> UseDefMap<'db> {
-    pub(crate) fn use_definitions(
+    pub(crate) fn bindings_at_use(
        &self,
        use_id: ScopedUseId,
-    ) -> DefinitionWithConstraintsIterator<'_, 'db> {
-        DefinitionWithConstraintsIterator {
-            all_definitions: &self.all_definitions,
-            all_constraints: &self.all_constraints,
-            inner: self.definitions_by_use[use_id].visible_definitions(),
-        }
+    ) -> BindingWithConstraintsIterator<'_, 'db> {
+        self.bindings_iterator(&self.bindings_by_use[use_id])
    }

    pub(crate) fn use_may_be_unbound(&self, use_id: ScopedUseId) -> bool {
-        self.definitions_by_use[use_id].may_be_unbound()
+        self.bindings_by_use[use_id].may_be_unbound()
    }

-    pub(crate) fn public_definitions(
+    pub(crate) fn public_bindings(
        &self,
        symbol: ScopedSymbolId,
-    ) -> DefinitionWithConstraintsIterator<'_, 'db> {
-        DefinitionWithConstraintsIterator {
-            all_definitions: &self.all_definitions,
-            all_constraints: &self.all_constraints,
-            inner: self.public_definitions[symbol].visible_definitions(),
-        }
+    ) -> BindingWithConstraintsIterator<'_, 'db> {
+        self.bindings_iterator(self.public_symbols[symbol].bindings())
    }

    pub(crate) fn public_may_be_unbound(&self, symbol: ScopedSymbolId) -> bool {
-        self.public_definitions[symbol].may_be_unbound()
+        self.public_symbols[symbol].may_be_unbound()
+    }
+
+    pub(crate) fn bindings_at_declaration(
+        &self,
+        declaration: Definition<'db>,
+    ) -> BindingWithConstraintsIterator<'_, 'db> {
+        if let SymbolDefinitions::Bindings(bindings) = &self.definitions_by_definition[&declaration]
+        {
+            self.bindings_iterator(bindings)
+        } else {
+            unreachable!("Declaration has non-Bindings in definitions_by_definition");
+        }
+    }
+
+    pub(crate) fn declarations_at_binding(
+        &self,
+        binding: Definition<'db>,
+    ) -> DeclarationsIterator<'_, 'db> {
+        if let SymbolDefinitions::Declarations(declarations) =
+            &self.definitions_by_definition[&binding]
+        {
+            self.declarations_iterator(declarations)
+        } else {
+            unreachable!("Binding has non-Declarations in definitions_by_definition");
+        }
+    }
+
+    pub(crate) fn public_declarations(
+        &self,
+        symbol: ScopedSymbolId,
+    ) -> DeclarationsIterator<'_, 'db> {
+        let declarations = self.public_symbols[symbol].declarations();
+        self.declarations_iterator(declarations)
+    }
+
+    pub(crate) fn has_public_declarations(&self, symbol: ScopedSymbolId) -> bool {
+        !self.public_symbols[symbol].declarations().is_empty()
+    }
+
+    fn bindings_iterator<'a>(
+        &'a self,
+        bindings: &'a SymbolBindings,
+    ) -> BindingWithConstraintsIterator<'a, 'db> {
+        BindingWithConstraintsIterator {
+            all_definitions: &self.all_definitions,
+            all_constraints: &self.all_constraints,
+            inner: bindings.iter(),
+        }
+    }
+
+    fn declarations_iterator<'a>(
+        &'a self,
+        declarations: &'a SymbolDeclarations,
+    ) -> DeclarationsIterator<'a, 'db> {
+        DeclarationsIterator {
+            all_definitions: &self.all_definitions,
+            inner: declarations.iter(),
+            may_be_undeclared: declarations.may_be_undeclared(),
+        }
    }
 }

-#[derive(Debug)]
-pub(crate) struct DefinitionWithConstraintsIterator<'map, 'db> {
-    all_definitions: &'map IndexVec<ScopedDefinitionId, Definition<'db>>,
-    all_constraints: &'map IndexVec<ScopedConstraintId, Expression<'db>>,
-    inner: DefinitionIdWithConstraintsIterator<'map>,
+/// Either live bindings or live declarations for a symbol.
+#[derive(Debug, PartialEq, Eq)]
+enum SymbolDefinitions {
+    Bindings(SymbolBindings),
+    Declarations(SymbolDeclarations),
 }

-impl<'map, 'db> Iterator for DefinitionWithConstraintsIterator<'map, 'db> {
-    type Item = DefinitionWithConstraints<'map, 'db>;
+#[derive(Debug)]
+pub(crate) struct BindingWithConstraintsIterator<'map, 'db> {
+    all_definitions: &'map IndexVec<ScopedDefinitionId, Definition<'db>>,
+    all_constraints: &'map IndexVec<ScopedConstraintId, Constraint<'db>>,
+    inner: BindingIdWithConstraintsIterator<'map>,
+}
+
+impl<'map, 'db> Iterator for BindingWithConstraintsIterator<'map, 'db> {
+    type Item = BindingWithConstraints<'map, 'db>;

    fn next(&mut self) -> Option<Self::Item> {
        self.inner
            .next()
-            .map(|def_id_with_constraints| DefinitionWithConstraints {
-                definition: self.all_definitions[def_id_with_constraints.definition],
+            .map(|def_id_with_constraints| BindingWithConstraints {
+                binding: self.all_definitions[def_id_with_constraints.definition],
                constraints: ConstraintsIterator {
                    all_constraints: self.all_constraints,
                    constraint_ids: def_id_with_constraints.constraint_ids,
@@ -224,20 +379,20 @@ impl<'map, 'db> Iterator for DefinitionWithConstraintsIterator<'map, 'db> {
    }
 }

-impl std::iter::FusedIterator for DefinitionWithConstraintsIterator<'_, '_> {}
+impl std::iter::FusedIterator for BindingWithConstraintsIterator<'_, '_> {}

-pub(crate) struct DefinitionWithConstraints<'map, 'db> {
-    pub(crate) definition: Definition<'db>,
+pub(crate) struct BindingWithConstraints<'map, 'db> {
+    pub(crate) binding: Definition<'db>,
    pub(crate) constraints: ConstraintsIterator<'map, 'db>,
 }

 pub(crate) struct ConstraintsIterator<'map, 'db> {
-    all_constraints: &'map IndexVec<ScopedConstraintId, Expression<'db>>,
+    all_constraints: &'map IndexVec<ScopedConstraintId, Constraint<'db>>,
    constraint_ids: ConstraintIdIterator<'map>,
 }

 impl<'map, 'db> Iterator for ConstraintsIterator<'map, 'db> {
-    type Item = Expression<'db>;
+    type Item = Constraint<'db>;

    fn next(&mut self) -> Option<Self::Item> {
        self.constraint_ids
@@ -248,25 +403,50 @@ impl<'map, 'db> Iterator for ConstraintsIterator<'map, 'db> {

 impl std::iter::FusedIterator for ConstraintsIterator<'_, '_> {}

+pub(crate) struct DeclarationsIterator<'map, 'db> {
+    all_definitions: &'map IndexVec<ScopedDefinitionId, Definition<'db>>,
+    inner: DeclarationIdIterator<'map>,
+    may_be_undeclared: bool,
+}
+
+impl DeclarationsIterator<'_, '_> {
+    pub(crate) fn may_be_undeclared(&self) -> bool {
+        self.may_be_undeclared
+    }
+}
+
+impl<'map, 'db> Iterator for DeclarationsIterator<'map, 'db> {
+    type Item = Definition<'db>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.inner.next().map(|def_id| self.all_definitions[def_id])
+    }
+}
+
+impl std::iter::FusedIterator for DeclarationsIterator<'_, '_> {}
+
 /// A snapshot of the definitions and constraints state at a particular point in control flow.
 #[derive(Clone, Debug)]
 pub(super) struct FlowSnapshot {
-    definitions_by_symbol: IndexVec<ScopedSymbolId, SymbolState>,
+    symbol_states: IndexVec<ScopedSymbolId, SymbolState>,
 }

 #[derive(Debug, Default)]
 pub(super) struct UseDefMapBuilder<'db> {
-    /// Append-only array of [`Definition`]; None is unbound.
+    /// Append-only array of [`Definition`].
    all_definitions: IndexVec<ScopedDefinitionId, Definition<'db>>,

-    /// Append-only array of constraints (as [`Expression`]).
-    all_constraints: IndexVec<ScopedConstraintId, Expression<'db>>,
+    /// Append-only array of [`Constraint`].
+    all_constraints: IndexVec<ScopedConstraintId, Constraint<'db>>,

-    /// Visible definitions at each so-far-recorded use.
-    definitions_by_use: IndexVec<ScopedUseId, SymbolState>,
+    /// Live bindings at each so-far-recorded use.
+    bindings_by_use: IndexVec<ScopedUseId, SymbolBindings>,

-    /// Currently visible definitions for each symbol.
-    definitions_by_symbol: IndexVec<ScopedSymbolId, SymbolState>,
+    /// Live bindings or declarations for each so-far-recorded definition.
+    definitions_by_definition: FxHashMap<Definition<'db>, SymbolDefinitions>,
+
+    /// Currently live bindings and declarations for each symbol.
+    symbol_states: IndexVec<ScopedSymbolId, SymbolState>,
 }

 impl<'db> UseDefMapBuilder<'db> {
@@ -275,86 +455,104 @@ impl<'db> UseDefMapBuilder<'db> {
    }

    pub(super) fn add_symbol(&mut self, symbol: ScopedSymbolId) {
-        let new_symbol = self.definitions_by_symbol.push(SymbolState::unbound());
+        let new_symbol = self.symbol_states.push(SymbolState::undefined());
        debug_assert_eq!(symbol, new_symbol);
    }

-    pub(super) fn record_definition(
+    pub(super) fn record_binding(&mut self, symbol: ScopedSymbolId, binding: Definition<'db>) {
+        let def_id = self.all_definitions.push(binding);
+        let symbol_state = &mut self.symbol_states[symbol];
+        self.definitions_by_definition.insert(
+            binding,
+            SymbolDefinitions::Declarations(symbol_state.declarations().clone()),
+        );
+        symbol_state.record_binding(def_id);
+    }
+
+    pub(super) fn record_constraint(&mut self, constraint: Constraint<'db>) {
+        let constraint_id = self.all_constraints.push(constraint);
+        for state in &mut self.symbol_states {
+            state.record_constraint(constraint_id);
+        }
+    }
+
+    pub(super) fn record_declaration(
+        &mut self,
+        symbol: ScopedSymbolId,
+        declaration: Definition<'db>,
+    ) {
+        let def_id = self.all_definitions.push(declaration);
+        let symbol_state = &mut self.symbol_states[symbol];
+        self.definitions_by_definition.insert(
+            declaration,
+            SymbolDefinitions::Bindings(symbol_state.bindings().clone()),
+        );
+        symbol_state.record_declaration(def_id);
+    }
+
+    pub(super) fn record_declaration_and_binding(
        &mut self,
        symbol: ScopedSymbolId,
        definition: Definition<'db>,
    ) {
-        // We have a new definition of a symbol; this replaces any previous definitions in this
-        // path.
+        // We don't need to store anything in self.definitions_by_definition.
        let def_id = self.all_definitions.push(definition);
-        self.definitions_by_symbol[symbol] = SymbolState::with(def_id);
-    }
-
-    pub(super) fn record_constraint(&mut self, constraint: Expression<'db>) {
-        let constraint_id = self.all_constraints.push(constraint);
-        for definitions in &mut self.definitions_by_symbol {
-            definitions.add_constraint(constraint_id);
-        }
+        let symbol_state = &mut self.symbol_states[symbol];
+        symbol_state.record_declaration(def_id);
+        symbol_state.record_binding(def_id);
    }

    pub(super) fn record_use(&mut self, symbol: ScopedSymbolId, use_id: ScopedUseId) {
-        // We have a use of a symbol; clone the currently visible definitions for that symbol, and
-        // record them as the visible definitions for this use.
+        // We have a use of a symbol; clone the current bindings for that symbol, and record them
+        // as the live bindings for this use.
        let new_use = self
-            .definitions_by_use
-            .push(self.definitions_by_symbol[symbol].clone());
+            .bindings_by_use
+            .push(self.symbol_states[symbol].bindings().clone());
        debug_assert_eq!(use_id, new_use);
    }

    /// Take a snapshot of the current visible-symbols state.
    pub(super) fn snapshot(&self) -> FlowSnapshot {
        FlowSnapshot {
-            definitions_by_symbol: self.definitions_by_symbol.clone(),
+            symbol_states: self.symbol_states.clone(),
        }
    }

-    /// Restore the current builder visible-definitions state to the given snapshot.
+    /// Restore the current builder symbols state to the given snapshot.
    pub(super) fn restore(&mut self, snapshot: FlowSnapshot) {
-        // We never remove symbols from `definitions_by_symbol` (it's an IndexVec, and the symbol
+        // We never remove symbols from `symbol_states` (it's an IndexVec, and the symbol
        // IDs must line up), so the current number of known symbols must always be equal to or
        // greater than the number of known symbols in a previously-taken snapshot.
-        let num_symbols = self.definitions_by_symbol.len();
-        debug_assert!(num_symbols >= snapshot.definitions_by_symbol.len());
+        let num_symbols = self.symbol_states.len();
+        debug_assert!(num_symbols >= snapshot.symbol_states.len());

        // Restore the current visible-definitions state to the given snapshot.
-        self.definitions_by_symbol = snapshot.definitions_by_symbol;
+        self.symbol_states = snapshot.symbol_states;

        // If the snapshot we are restoring is missing some symbols we've recorded since, we need
        // to fill them in so the symbol IDs continue to line up. Since they don't exist in the
-        // snapshot, the correct state to fill them in with is "unbound".
-        self.definitions_by_symbol
-            .resize(num_symbols, SymbolState::unbound());
+        // snapshot, the correct state to fill them in with is "undefined".
+        self.symbol_states
+            .resize(num_symbols, SymbolState::undefined());
    }

    /// Merge the given snapshot into the current state, reflecting that we might have taken either
-    /// path to get here. The new visible-definitions state for each symbol should include
-    /// definitions from both the prior state and the snapshot.
+    /// path to get here. The new state for each symbol should include definitions from both the
+    /// prior state and the snapshot.
    pub(super) fn merge(&mut self, snapshot: FlowSnapshot) {
-        // The tricky thing about merging two Ranges pointing into `all_definitions` is that if the
-        // two Ranges aren't already adjacent in `all_definitions`, we will have to copy at least
-        // one or the other of the ranges to the end of `all_definitions` so as to make them
-        // adjacent. We can't ever move things around in `all_definitions` because previously
-        // recorded uses may still have ranges pointing to any part of it; all we can do is append.
-        // It's possible we may end up with some old entries in `all_definitions` that nobody is
-        // pointing to, but that's OK.
-
-        // We never remove symbols from `definitions_by_symbol` (it's an IndexVec, and the symbol
+        // We never remove symbols from `symbol_states` (it's an IndexVec, and the symbol
        // IDs must line up), so the current number of known symbols must always be equal to or
        // greater than the number of known symbols in a previously-taken snapshot.
-        debug_assert!(self.definitions_by_symbol.len() >= snapshot.definitions_by_symbol.len());
+        debug_assert!(self.symbol_states.len() >= snapshot.symbol_states.len());

-        let mut snapshot_definitions_iter = snapshot.definitions_by_symbol.into_iter();
-        for current in &mut self.definitions_by_symbol {
+        let mut snapshot_definitions_iter = snapshot.symbol_states.into_iter();
+        for current in &mut self.symbol_states {
            if let Some(snapshot) = snapshot_definitions_iter.next() {
                current.merge(snapshot);
            } else {
-                // Symbol not present in snapshot, so it's unbound from that path.
-                current.add_unbound();
+                // Symbol not present in snapshot, so it's unbound/undeclared from that path.
+                current.set_may_be_unbound();
+                current.set_may_be_undeclared();
            }
        }
    }
@@ -362,14 +560,16 @@ impl<'db> UseDefMapBuilder<'db> {
    pub(super) fn finish(mut self) -> UseDefMap<'db> {
        self.all_definitions.shrink_to_fit();
        self.all_constraints.shrink_to_fit();
-        self.definitions_by_symbol.shrink_to_fit();
-        self.definitions_by_use.shrink_to_fit();
+        self.symbol_states.shrink_to_fit();
+        self.bindings_by_use.shrink_to_fit();
+        self.definitions_by_definition.shrink_to_fit();

        UseDefMap {
            all_definitions: self.all_definitions,
            all_constraints: self.all_constraints,
-            definitions_by_use: self.definitions_by_use,
-            public_definitions: self.definitions_by_symbol,
+            bindings_by_use: self.bindings_by_use,
+            public_symbols: self.symbol_states,
+            definitions_by_definition: self.definitions_by_definition,
        }
    }
 }
--- a/crates/red_knot_python_semantic/src/semantic_index/use_def/bitset.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/use_def/bitset.rs
@@ -32,17 +32,25 @@ impl<const B: usize> BitSet<B> {
        bitset
    }

+    pub(super) fn is_empty(&self) -> bool {
+        self.blocks().iter().all(|&b| b == 0)
+    }
+
    /// Convert from Inline to Heap, if needed, and resize the Heap vector, if needed.
    fn resize(&mut self, value: u32) {
        let num_blocks_needed = (value / 64) + 1;
+        self.resize_blocks(num_blocks_needed as usize);
+    }
+
+    fn resize_blocks(&mut self, num_blocks_needed: usize) {
        match self {
            Self::Inline(blocks) => {
                let mut vec = blocks.to_vec();
-                vec.resize(num_blocks_needed as usize, 0);
+                vec.resize(num_blocks_needed, 0);
                *self = Self::Heap(vec);
            }
            Self::Heap(vec) => {
-                vec.resize(num_blocks_needed as usize, 0);
+                vec.resize(num_blocks_needed, 0);
            }
        }
    }
@@ -89,6 +97,19 @@ impl<const B: usize> BitSet<B> {
        }
    }

+    /// Union in-place with another [`BitSet`].
+    pub(super) fn union(&mut self, other: &BitSet<B>) {
+        let mut max_len = self.blocks().len();
+        let other_len = other.blocks().len();
+        if other_len > max_len {
+            max_len = other_len;
+            self.resize_blocks(max_len);
+        }
+        for (my_block, other_block) in self.blocks_mut().iter_mut().zip(other.blocks()) {
+            *my_block |= other_block;
+        }
+    }
+
    /// Return an iterator over the values (in ascending order) in this [`BitSet`].
    pub(super) fn iter(&self) -> BitSetIterator<'_, B> {
        let blocks = self.blocks();
@@ -218,6 +239,59 @@ mod tests {
        assert_bitset(&b1, &[89]);
    }

+    #[test]
+    fn union() {
+        let mut b1 = BitSet::<1>::with(2);
+        let b2 = BitSet::<1>::with(4);
+
+        b1.union(&b2);
+        assert_bitset(&b1, &[2, 4]);
+    }
+
+    #[test]
+    fn union_mixed_1() {
+        let mut b1 = BitSet::<1>::with(4);
+        let mut b2 = BitSet::<1>::with(4);
+        b1.insert(89);
+        b2.insert(5);
+
+        b1.union(&b2);
+        assert_bitset(&b1, &[4, 5, 89]);
+    }
+
+    #[test]
+    fn union_mixed_2() {
+        let mut b1 = BitSet::<1>::with(4);
+        let mut b2 = BitSet::<1>::with(4);
+        b1.insert(23);
+        b2.insert(89);
+
+        b1.union(&b2);
+        assert_bitset(&b1, &[4, 23, 89]);
+    }
+
+    #[test]
+    fn union_heap() {
+        let mut b1 = BitSet::<1>::with(4);
+        let mut b2 = BitSet::<1>::with(4);
+        b1.insert(89);
+        b2.insert(90);
+
+        b1.union(&b2);
+        assert_bitset(&b1, &[4, 89, 90]);
+    }
+
+    #[test]
+    fn union_heap_2() {
+        let mut b1 = BitSet::<1>::with(89);
+        let mut b2 = BitSet::<1>::with(89);
+        b1.insert(91);
+        b2.insert(90);
+
+        b1.union(&b2);
+        assert_bitset(&b1, &[89, 90, 91]);
+    }
+
    #[test]
    fn multiple_blocks() {
        let mut b = BitSet::<2>::with(120);
@@ -225,4 +299,11 @@ mod tests {
        assert!(matches!(b, BitSet::Inline(_)));
        assert_bitset(&b, &[45, 120]);
    }
+
+    #[test]
+    fn empty() {
+        let b = BitSet::<1>::default();
+
+        assert!(b.is_empty());
+    }
 }
--- a/crates/red_knot_python_semantic/src/semantic_index/use_def/symbol_state.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/use_def/symbol_state.rs
@@ -1,13 +1,13 @@
-//! Track visible definitions of a symbol, and applicable constraints per definition.
+//! Track live bindings per symbol, applicable constraints per binding, and live declarations.
 //!
 //! These data structures operate entirely on scope-local newtype-indices for definitions and
 //! constraints, referring to their location in the `all_definitions` and `all_constraints`
 //! indexvecs in [`super::UseDefMapBuilder`].
 //!
-//! We need to track arbitrary associations between definitions and constraints, not just a single
-//! set of currently dominating constraints (where "dominating" means "control flow must have
-//! passed through it to reach this point"), because we can have dominating constraints that apply
-//! to some definitions but not others, as in this code:
+//! We need to track arbitrary associations between bindings and constraints, not just a single set
+//! of currently dominating constraints (where "dominating" means "control flow must have passed
+//! through it to reach this point"), because we can have dominating constraints that apply to some
+//! bindings but not others, as in this code:
 //!
 //! ```python
 //! x = 1 if flag else None
@@ -18,11 +18,11 @@
 //! ```
 //!
 //! The `x is not None` constraint dominates the final use of `x`, but it applies only to the first
-//! definition of `x`, not the second, so `None` is a possible value for `x`.
+//! binding of `x`, not the second, so `None` is a possible value for `x`.
 //!
-//! And we can't just track, for each definition, an index into a list of dominating constraints,
-//! either, because we can have definitions which are still visible, but subject to constraints
-//! that are no longer dominating, as in this code:
+//! And we can't just track, for each binding, an index into a list of dominating constraints,
+//! either, because we can have bindings which are still visible, but subject to constraints that
+//! are no longer dominating, as in this code:
 //!
 //! ```python
 //! x = 0
@@ -33,13 +33,16 @@
 //! ```
 //!
 //! From the point of view of the final use of `x`, the `x is not None` constraint no longer
-//! dominates, but it does dominate the `x = 1 if flag2 else None` definition, so we have to keep
+//! dominates, but it does dominate the `x = 1 if flag2 else None` binding, so we have to keep
 //! track of that.
 //!
 //! The data structures used here ([`BitSet`] and [`smallvec::SmallVec`]) optimize for keeping all
 //! data inline (avoiding lots of scattered allocations) in small-to-medium cases, and falling back
-//! to heap allocation to be able to scale to arbitrary numbers of definitions and constraints when
-//! needed.
+//! to heap allocation to be able to scale to arbitrary numbers of live bindings and constraints
+//! when needed.
+//!
+//! Tracking live declarations is simpler, since constraints are not involved, but otherwise very
+//! similar to tracking live bindings.
 use super::bitset::{BitSet, BitSetIterator};
 use ruff_index::newtype_index;
 use smallvec::SmallVec;
@@ -53,93 +56,200 @@ pub(super) struct ScopedDefinitionId;
 pub(super) struct ScopedConstraintId;

 /// Can reference this * 64 total definitions inline; more will fall back to the heap.
-const INLINE_DEFINITION_BLOCKS: usize = 3;
+const INLINE_BINDING_BLOCKS: usize = 3;

-/// A [`BitSet`] of [`ScopedDefinitionId`], representing visible definitions of a symbol in a scope.
-type Definitions = BitSet<INLINE_DEFINITION_BLOCKS>;
-type DefinitionsIterator<'a> = BitSetIterator<'a, INLINE_DEFINITION_BLOCKS>;
+/// A [`BitSet`] of [`ScopedDefinitionId`], representing live bindings of a symbol in a scope.
+type Bindings = BitSet<INLINE_BINDING_BLOCKS>;
+type BindingsIterator<'a> = BitSetIterator<'a, INLINE_BINDING_BLOCKS>;
+
+/// Can reference this * 64 total declarations inline; more will fall back to the heap.
+const INLINE_DECLARATION_BLOCKS: usize = 3;
+
+/// A [`BitSet`] of [`ScopedDefinitionId`], representing live declarations of a symbol in a scope.
+type Declarations = BitSet<INLINE_DECLARATION_BLOCKS>;
+type DeclarationsIterator<'a> = BitSetIterator<'a, INLINE_DECLARATION_BLOCKS>;

 /// Can reference this * 64 total constraints inline; more will fall back to the heap.
 const INLINE_CONSTRAINT_BLOCKS: usize = 2;

-/// Can keep inline this many visible definitions per symbol at a given time; more will go to heap.
-const INLINE_VISIBLE_DEFINITIONS_PER_SYMBOL: usize = 4;
+/// Can keep inline this many live bindings per symbol at a given time; more will go to heap.
+const INLINE_BINDINGS_PER_SYMBOL: usize = 4;

-/// One [`BitSet`] of applicable [`ScopedConstraintId`] per visible definition.
-type InlineConstraintArray =
-    [BitSet<INLINE_CONSTRAINT_BLOCKS>; INLINE_VISIBLE_DEFINITIONS_PER_SYMBOL];
+/// One [`BitSet`] of applicable [`ScopedConstraintId`] per live binding.
+type InlineConstraintArray = [BitSet<INLINE_CONSTRAINT_BLOCKS>; INLINE_BINDINGS_PER_SYMBOL];
 type Constraints = SmallVec<InlineConstraintArray>;
 type ConstraintsIterator<'a> = std::slice::Iter<'a, BitSet<INLINE_CONSTRAINT_BLOCKS>>;
 type ConstraintsIntoIterator = smallvec::IntoIter<InlineConstraintArray>;

-/// Visible definitions and narrowing constraints for a single symbol at some point in control flow.
+/// Live declarations for a single symbol at some point in control flow.
 #[derive(Clone, Debug, PartialEq, Eq)]
-pub(super) struct SymbolState {
-    /// [`BitSet`]: which [`ScopedDefinitionId`] are visible for this symbol?
-    visible_definitions: Definitions,
+pub(super) struct SymbolDeclarations {
+    /// [`BitSet`]: which declarations (as [`ScopedDefinitionId`]) can reach the current location?
+    live_declarations: Declarations,

-    /// For each definition, which [`ScopedConstraintId`] apply?
+    /// Could the symbol be un-declared at this point?
+    may_be_undeclared: bool,
+}
+
+impl SymbolDeclarations {
+    fn undeclared() -> Self {
+        Self {
+            live_declarations: Declarations::default(),
+            may_be_undeclared: true,
+        }
+    }
+
+    /// Record a newly-encountered declaration for this symbol.
+    fn record_declaration(&mut self, declaration_id: ScopedDefinitionId) {
+        self.live_declarations = Declarations::with(declaration_id.into());
+        self.may_be_undeclared = false;
+    }
+
+    /// Add undeclared as a possibility for this symbol.
+    fn set_may_be_undeclared(&mut self) {
+        self.may_be_undeclared = true;
+    }
+
+    /// Return an iterator over live declarations for this symbol.
+    pub(super) fn iter(&self) -> DeclarationIdIterator {
+        DeclarationIdIterator {
+            inner: self.live_declarations.iter(),
+        }
+    }
+
+    pub(super) fn is_empty(&self) -> bool {
+        self.live_declarations.is_empty()
+    }
+
+    pub(super) fn may_be_undeclared(&self) -> bool {
+        self.may_be_undeclared
+    }
+}
+
+/// Live bindings and narrowing constraints for a single symbol at some point in control flow.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(super) struct SymbolBindings {
+    /// [`BitSet`]: which bindings (as [`ScopedDefinitionId`]) can reach the current location?
+    live_bindings: Bindings,
+
+    /// For each live binding, which [`ScopedConstraintId`] apply?
    ///
    /// This is a [`smallvec::SmallVec`] which should always have one [`BitSet`] of constraints per
-    /// definition in `visible_definitions`.
+    /// binding in `live_bindings`.
    constraints: Constraints,

    /// Could the symbol be unbound at this point?
    may_be_unbound: bool,
 }

-/// A single [`ScopedDefinitionId`] with an iterator of its applicable [`ScopedConstraintId`].
-#[derive(Debug)]
-pub(super) struct DefinitionIdWithConstraints<'a> {
-    pub(super) definition: ScopedDefinitionId,
-    pub(super) constraint_ids: ConstraintIdIterator<'a>,
-}
-
-impl SymbolState {
-    /// Return a new [`SymbolState`] representing an unbound symbol.
-    pub(super) fn unbound() -> Self {
+impl SymbolBindings {
+    fn unbound() -> Self {
        Self {
-            visible_definitions: Definitions::default(),
+            live_bindings: Bindings::default(),
            constraints: Constraints::default(),
            may_be_unbound: true,
        }
    }

-    /// Return a new [`SymbolState`] representing a symbol with a single visible definition.
-    pub(super) fn with(definition_id: ScopedDefinitionId) -> Self {
-        let mut constraints = Constraints::with_capacity(1);
-        constraints.push(BitSet::default());
-        Self {
-            visible_definitions: Definitions::with(definition_id.into()),
-            constraints,
-            may_be_unbound: false,
-        }
-    }
-
    /// Add Unbound as a possibility for this symbol.
-    pub(super) fn add_unbound(&mut self) {
+    fn set_may_be_unbound(&mut self) {
        self.may_be_unbound = true;
    }

-    /// Add given constraint to all currently-visible definitions.
-    pub(super) fn add_constraint(&mut self, constraint_id: ScopedConstraintId) {
+    /// Record a newly-encountered binding for this symbol.
+    pub(super) fn record_binding(&mut self, binding_id: ScopedDefinitionId) {
+        // The new binding replaces all previous live bindings in this path, and has no
+        // constraints.
+        self.live_bindings = Bindings::with(binding_id.into());
+        self.constraints = Constraints::with_capacity(1);
+        self.constraints.push(BitSet::default());
+        self.may_be_unbound = false;
+    }
+
+    /// Add given constraint to all live bindings.
+    pub(super) fn record_constraint(&mut self, constraint_id: ScopedConstraintId) {
        for bitset in &mut self.constraints {
            bitset.insert(constraint_id.into());
        }
    }

+    /// Iterate over currently live bindings for this symbol.
+    pub(super) fn iter(&self) -> BindingIdWithConstraintsIterator {
+        BindingIdWithConstraintsIterator {
+            definitions: self.live_bindings.iter(),
+            constraints: self.constraints.iter(),
+        }
+    }
+
+    pub(super) fn may_be_unbound(&self) -> bool {
+        self.may_be_unbound
+    }
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(super) struct SymbolState {
+    declarations: SymbolDeclarations,
+    bindings: SymbolBindings,
+}
+
+impl SymbolState {
+    /// Return a new [`SymbolState`] representing an unbound, undeclared symbol.
+    pub(super) fn undefined() -> Self {
+        Self {
+            declarations: SymbolDeclarations::undeclared(),
+            bindings: SymbolBindings::unbound(),
+        }
+    }
+
+    /// Add Unbound as a possibility for this symbol.
+    pub(super) fn set_may_be_unbound(&mut self) {
+        self.bindings.set_may_be_unbound();
+    }
+
+    /// Record a newly-encountered binding for this symbol.
+    pub(super) fn record_binding(&mut self, binding_id: ScopedDefinitionId) {
+        self.bindings.record_binding(binding_id);
+    }
+
+    /// Add given constraint to all live bindings.
+    pub(super) fn record_constraint(&mut self, constraint_id: ScopedConstraintId) {
+        self.bindings.record_constraint(constraint_id);
+    }
+
+    /// Add undeclared as a possibility for this symbol.
+    pub(super) fn set_may_be_undeclared(&mut self) {
+        self.declarations.set_may_be_undeclared();
+    }
+
+    /// Record a newly-encountered declaration of this symbol.
+    pub(super) fn record_declaration(&mut self, declaration_id: ScopedDefinitionId) {
+        self.declarations.record_declaration(declaration_id);
+    }
+
    /// Merge another [`SymbolState`] into this one.
    pub(super) fn merge(&mut self, b: SymbolState) {
        let mut a = Self {
-            visible_definitions: Definitions::default(),
-            constraints: Constraints::default(),
-            may_be_unbound: self.may_be_unbound || b.may_be_unbound,
+            bindings: SymbolBindings {
+                live_bindings: Bindings::default(),
+                constraints: Constraints::default(),
+                may_be_unbound: self.bindings.may_be_unbound || b.bindings.may_be_unbound,
+            },
+            declarations: SymbolDeclarations {
+                live_declarations: self.declarations.live_declarations.clone(),
+                may_be_undeclared: self.declarations.may_be_undeclared
+                    || b.declarations.may_be_undeclared,
+            },
        };
+
        std::mem::swap(&mut a, self);
-        let mut a_defs_iter = a.visible_definitions.iter();
-        let mut b_defs_iter = b.visible_definitions.iter();
-        let mut a_constraints_iter = a.constraints.into_iter();
-        let mut b_constraints_iter = b.constraints.into_iter();
+        self.declarations
+            .live_declarations
+            .union(&b.declarations.live_declarations);
+
+        let mut a_defs_iter = a.bindings.live_bindings.iter();
+        let mut b_defs_iter = b.bindings.live_bindings.iter();
+        let mut a_constraints_iter = a.bindings.constraints.into_iter();
+        let mut b_constraints_iter = b.bindings.constraints.into_iter();

        let mut opt_a_def: Option<u32> = a_defs_iter.next();
        let mut opt_b_def: Option<u32> = b_defs_iter.next();
@@ -152,7 +262,7 @@ impl SymbolState {

        // Helper to push `def`, with constraints in `constraints_iter`, onto `self`.
        let push = |def, constraints_iter: &mut ConstraintsIntoIterator, merged: &mut Self| {
-            merged.visible_definitions.insert(def);
+            merged.bindings.live_bindings.insert(def);
            // SAFETY: we only ever create SymbolState with either no definitions and no constraint
            // bitsets (`::unbound`) or one definition and one constraint bitset (`::with`), and
            // `::merge` always pushes one definition and one constraint bitset together (just
@@ -161,7 +271,7 @@ impl SymbolState {
            let constraints = constraints_iter
                .next()
                .expect("definitions and constraints length mismatch");
-            merged.constraints.push(constraints);
+            merged.bindings.constraints.push(constraints);
        };

        loop {
@@ -191,7 +301,8 @@ impl SymbolState {
                        // If the same definition is visible through both paths, any constraint
                        // that applies on only one path is irrelevant to the resulting type from
                        // unioning the two paths, so we intersect the constraints.
-                        self.constraints
+                        self.bindings
+                            .constraints
                            .last_mut()
                            .unwrap()
                            .intersect(&a_constraints);
@@ -214,40 +325,49 @@ impl SymbolState {
        }
    }

-    /// Get iterator over visible definitions with constraints.
-    pub(super) fn visible_definitions(&self) -> DefinitionIdWithConstraintsIterator {
-        DefinitionIdWithConstraintsIterator {
-            definitions: self.visible_definitions.iter(),
-            constraints: self.constraints.iter(),
-        }
+    pub(super) fn bindings(&self) -> &SymbolBindings {
+        &self.bindings
+    }
+
+    pub(super) fn declarations(&self) -> &SymbolDeclarations {
+        &self.declarations
    }

    /// Could the symbol be unbound?
    pub(super) fn may_be_unbound(&self) -> bool {
-        self.may_be_unbound
+        self.bindings.may_be_unbound()
    }
 }

-/// The default state of a symbol (if we've seen no definitions of it) is unbound.
+/// The default state of a symbol, if we've seen no definitions of it, is undefined (that is,
+/// both unbound and undeclared).
 impl Default for SymbolState {
    fn default() -> Self {
-        SymbolState::unbound()
+        SymbolState::undefined()
    }
 }

+/// A single binding (as [`ScopedDefinitionId`]) with an iterator of its applicable
+/// [`ScopedConstraintId`].
+#[derive(Debug)]
+pub(super) struct BindingIdWithConstraints<'a> {
+    pub(super) definition: ScopedDefinitionId,
+    pub(super) constraint_ids: ConstraintIdIterator<'a>,
+}
+
 #[derive(Debug)]
-pub(super) struct DefinitionIdWithConstraintsIterator<'a> {
-    definitions: DefinitionsIterator<'a>,
+pub(super) struct BindingIdWithConstraintsIterator<'a> {
+    definitions: BindingsIterator<'a>,
    constraints: ConstraintsIterator<'a>,
 }

-impl<'a> Iterator for DefinitionIdWithConstraintsIterator<'a> {
-    type Item = DefinitionIdWithConstraints<'a>;
+impl<'a> Iterator for BindingIdWithConstraintsIterator<'a> {
+    type Item = BindingIdWithConstraints<'a>;

    fn next(&mut self) -> Option<Self::Item> {
        match (self.definitions.next(), self.constraints.next()) {
            (None, None) => None,
-            (Some(def), Some(constraints)) => Some(DefinitionIdWithConstraints {
+            (Some(def), Some(constraints)) => Some(BindingIdWithConstraints {
                definition: ScopedDefinitionId::from_u32(def),
                constraint_ids: ConstraintIdIterator {
                    wrapped: constraints.iter(),
@@ -259,7 +379,7 @@ impl<'a> Iterator for DefinitionIdWithConstraintsIterator<'a> {
    }
 }

-impl std::iter::FusedIterator for DefinitionIdWithConstraintsIterator<'_> {}
+impl std::iter::FusedIterator for BindingIdWithConstraintsIterator<'_> {}

 #[derive(Debug)]
 pub(super) struct ConstraintIdIterator<'a> {
@@ -276,99 +396,193 @@ impl Iterator for ConstraintIdIterator<'_> {

 impl std::iter::FusedIterator for ConstraintIdIterator<'_> {}

+#[derive(Debug)]
+pub(super) struct DeclarationIdIterator<'a> {
+    inner: DeclarationsIterator<'a>,
+}
+
+impl<'a> Iterator for DeclarationIdIterator<'a> {
+    type Item = ScopedDefinitionId;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.inner.next().map(ScopedDefinitionId::from_u32)
+    }
+}
+
+impl std::iter::FusedIterator for DeclarationIdIterator<'_> {}
+
 #[cfg(test)]
 mod tests {
    use super::{ScopedConstraintId, ScopedDefinitionId, SymbolState};

-    impl SymbolState {
-        pub(crate) fn assert(&self, may_be_unbound: bool, expected: &[&str]) {
-            assert_eq!(self.may_be_unbound(), may_be_unbound);
-            let actual = self
-                .visible_definitions()
-                .map(|def_id_with_constraints| {
-                    format!(
-                        "{}<{}>",
-                        def_id_with_constraints.definition.as_u32(),
-                        def_id_with_constraints
-                            .constraint_ids
-                            .map(ScopedConstraintId::as_u32)
-                            .map(|idx| idx.to_string())
-                            .collect::<Vec<_>>()
-                            .join(", ")
-                    )
-                })
-                .collect::<Vec<_>>();
-            assert_eq!(actual, expected);
-        }
+    fn assert_bindings(symbol: &SymbolState, may_be_unbound: bool, expected: &[&str]) {
+        assert_eq!(symbol.may_be_unbound(), may_be_unbound);
+        let actual = symbol
+            .bindings()
+            .iter()
+            .map(|def_id_with_constraints| {
+                format!(
+                    "{}<{}>",
+                    def_id_with_constraints.definition.as_u32(),
+                    def_id_with_constraints
+                        .constraint_ids
+                        .map(ScopedConstraintId::as_u32)
+                        .map(|idx| idx.to_string())
+                        .collect::<Vec<_>>()
+                        .join(", ")
+                )
+            })
+            .collect::<Vec<_>>();
+        assert_eq!(actual, expected);
+    }
+
+    pub(crate) fn assert_declarations(
+        symbol: &SymbolState,
+        may_be_undeclared: bool,
+        expected: &[u32],
+    ) {
+        assert_eq!(symbol.declarations.may_be_undeclared(), may_be_undeclared);
+        let actual = symbol
+            .declarations()
+            .iter()
+            .map(ScopedDefinitionId::as_u32)
+            .collect::<Vec<_>>();
+        assert_eq!(actual, expected);
    }

    #[test]
    fn unbound() {
-        let cd = SymbolState::unbound();
+        let sym = SymbolState::undefined();

-        cd.assert(true, &[]);
+        assert_bindings(&sym, true, &[]);
    }

    #[test]
    fn with() {
-        let cd = SymbolState::with(ScopedDefinitionId::from_u32(0));
+        let mut sym = SymbolState::undefined();
+        sym.record_binding(ScopedDefinitionId::from_u32(0));

-        cd.assert(false, &["0<>"]);
+        assert_bindings(&sym, false, &["0<>"]);
    }

    #[test]
-    fn add_unbound() {
-        let mut cd = SymbolState::with(ScopedDefinitionId::from_u32(0));
-        cd.add_unbound();
+    fn set_may_be_unbound() {
+        let mut sym = SymbolState::undefined();
+        sym.record_binding(ScopedDefinitionId::from_u32(0));
+        sym.set_may_be_unbound();

-        cd.assert(true, &["0<>"]);
+        assert_bindings(&sym, true, &["0<>"]);
    }

    #[test]
-    fn add_constraint() {
-        let mut cd = SymbolState::with(ScopedDefinitionId::from_u32(0));
-        cd.add_constraint(ScopedConstraintId::from_u32(0));
+    fn record_constraint() {
+        let mut sym = SymbolState::undefined();
+        sym.record_binding(ScopedDefinitionId::from_u32(0));
+        sym.record_constraint(ScopedConstraintId::from_u32(0));

-        cd.assert(false, &["0<0>"]);
+        assert_bindings(&sym, false, &["0<0>"]);
    }

    #[test]
    fn merge() {
        // merging the same definition with the same constraint keeps the constraint
-        let mut cd0a = SymbolState::with(ScopedDefinitionId::from_u32(0));
-        cd0a.add_constraint(ScopedConstraintId::from_u32(0));
+        let mut sym0a = SymbolState::undefined();
+        sym0a.record_binding(ScopedDefinitionId::from_u32(0));
+        sym0a.record_constraint(ScopedConstraintId::from_u32(0));

-        let mut cd0b = SymbolState::with(ScopedDefinitionId::from_u32(0));
-        cd0b.add_constraint(ScopedConstraintId::from_u32(0));
+        let mut sym0b = SymbolState::undefined();
+        sym0b.record_binding(ScopedDefinitionId::from_u32(0));
+        sym0b.record_constraint(ScopedConstraintId::from_u32(0));

-        cd0a.merge(cd0b);
-        let mut cd0 = cd0a;
-        cd0.assert(false, &["0<0>"]);
+        sym0a.merge(sym0b);
+        let mut sym0 = sym0a;
+        assert_bindings(&sym0, false, &["0<0>"]);

        // merging the same definition with differing constraints drops all constraints
-        let mut cd1a = SymbolState::with(ScopedDefinitionId::from_u32(1));
-        cd1a.add_constraint(ScopedConstraintId::from_u32(1));
+        let mut sym1a = SymbolState::undefined();
+        sym1a.record_binding(ScopedDefinitionId::from_u32(1));
+        sym1a.record_constraint(ScopedConstraintId::from_u32(1));

-        let mut cd1b = SymbolState::with(ScopedDefinitionId::from_u32(1));
-        cd1b.add_constraint(ScopedConstraintId::from_u32(2));
+        let mut sym1b = SymbolState::undefined();
+        sym1b.record_binding(ScopedDefinitionId::from_u32(1));
+        sym1b.record_constraint(ScopedConstraintId::from_u32(2));

-        cd1a.merge(cd1b);
-        let cd1 = cd1a;
-        cd1.assert(false, &["1<>"]);
+        sym1a.merge(sym1b);
+        let sym1 = sym1a;
+        assert_bindings(&sym1, false, &["1<>"]);

        // merging a constrained definition with unbound keeps both
-        let mut cd2a = SymbolState::with(ScopedDefinitionId::from_u32(2));
-        cd2a.add_constraint(ScopedConstraintId::from_u32(3));
+        let mut sym2a = SymbolState::undefined();
+        sym2a.record_binding(ScopedDefinitionId::from_u32(2));
+        sym2a.record_constraint(ScopedConstraintId::from_u32(3));

-        let cd2b = SymbolState::unbound();
+        let sym2b = SymbolState::undefined();

-        cd2a.merge(cd2b);
-        let cd2 = cd2a;
-        cd2.assert(true, &["2<3>"]);
+        sym2a.merge(sym2b);
+        let sym2 = sym2a;
+        assert_bindings(&sym2, true, &["2<3>"]);

        // merging different definitions keeps them each with their existing constraints
-        cd0.merge(cd2);
-        let cd = cd0;
-        cd.assert(true, &["0<0>", "2<3>"]);
+        sym0.merge(sym2);
+        let sym = sym0;
+        assert_bindings(&sym, true, &["0<0>", "2<3>"]);
+    }
+
+    #[test]
+    fn no_declaration() {
+        let sym = SymbolState::undefined();
+
+        assert_declarations(&sym, true, &[]);
+    }
+
+    #[test]
+    fn record_declaration() {
+        let mut sym = SymbolState::undefined();
+        sym.record_declaration(ScopedDefinitionId::from_u32(1));
+
+        assert_declarations(&sym, false, &[1]);
+    }
+
+    #[test]
+    fn record_declaration_override() {
+        let mut sym = SymbolState::undefined();
+        sym.record_declaration(ScopedDefinitionId::from_u32(1));
+        sym.record_declaration(ScopedDefinitionId::from_u32(2));
+
+        assert_declarations(&sym, false, &[2]);
+    }
+
+    #[test]
+    fn record_declaration_merge() {
+        let mut sym = SymbolState::undefined();
+        sym.record_declaration(ScopedDefinitionId::from_u32(1));
+
+        let mut sym2 = SymbolState::undefined();
+        sym2.record_declaration(ScopedDefinitionId::from_u32(2));
+
+        sym.merge(sym2);
+
+        assert_declarations(&sym, false, &[1, 2]);
+    }
+
+    #[test]
+    fn record_declaration_merge_partial_undeclared() {
+        let mut sym = SymbolState::undefined();
+        sym.record_declaration(ScopedDefinitionId::from_u32(1));
+
+        let sym2 = SymbolState::undefined();
+
+        sym.merge(sym2);
+
+        assert_declarations(&sym, true, &[1]);
+    }
+
+    #[test]
+    fn set_may_be_undeclared() {
+        let mut sym = SymbolState::undefined();
+        sym.record_declaration(ScopedDefinitionId::from_u32(0));
+        sym.set_may_be_undeclared();
+
+        assert_declarations(&sym, true, &[0]);
    }
 }
--- a/crates/red_knot_python_semantic/src/semantic_model.rs
+++ b/crates/red_knot_python_semantic/src/semantic_model.rs
@@ -8,7 +8,7 @@ use crate::module_name::ModuleName;
 use crate::module_resolver::{resolve_module, Module};
 use crate::semantic_index::ast_ids::HasScopedAstId;
 use crate::semantic_index::semantic_index;
-use crate::types::{definition_ty, global_symbol_ty_by_name, infer_scope_types, Type};
+use crate::types::{binding_ty, global_symbol_ty, infer_scope_types, Type};
 use crate::Db;

 pub struct SemanticModel<'db> {
@@ -40,7 +40,7 @@ impl<'db> SemanticModel<'db> {
    }

    pub fn global_symbol_ty(&self, module: &Module, symbol_name: &str) -> Type<'db> {
-        global_symbol_ty_by_name(self.db, module.file(), symbol_name)
+        global_symbol_ty(self.db, module.file(), symbol_name)
    }
 }

@@ -147,24 +147,24 @@ impl HasTy for ast::Expr {
    }
 }

-macro_rules! impl_definition_has_ty {
+macro_rules! impl_binding_has_ty {
    ($ty: ty) => {
        impl HasTy for $ty {
            #[inline]
            fn ty<'db>(&self, model: &SemanticModel<'db>) -> Type<'db> {
                let index = semantic_index(model.db, model.file);
-                let definition = index.definition(self);
-                definition_ty(model.db, definition)
+                let binding = index.definition(self);
+                binding_ty(model.db, binding)
            }
        }
    };
 }

-impl_definition_has_ty!(ast::StmtFunctionDef);
-impl_definition_has_ty!(ast::StmtClassDef);
-impl_definition_has_ty!(ast::Alias);
-impl_definition_has_ty!(ast::Parameter);
-impl_definition_has_ty!(ast::ParameterWithDefault);
+impl_binding_has_ty!(ast::StmtFunctionDef);
+impl_binding_has_ty!(ast::StmtClassDef);
+impl_binding_has_ty!(ast::Alias);
+impl_binding_has_ty!(ast::Parameter);
+impl_binding_has_ty!(ast::ParameterWithDefault);

 #[cfg(test)]
 mod tests {
--- a/crates/red_knot_python_semantic/src/stdlib.rs
+++ b/crates/red_knot_python_semantic/src/stdlib.rs
@@ -0,0 +1,87 @@
+use crate::module_name::ModuleName;
+use crate::module_resolver::resolve_module;
+use crate::semantic_index::global_scope;
+use crate::semantic_index::symbol::ScopeId;
+use crate::types::{global_symbol_ty, Type};
+use crate::Db;
+
+/// Enumeration of various core stdlib modules, for which we have dedicated Salsa queries.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum CoreStdlibModule {
+    Builtins,
+    Types,
+    Typeshed,
+    TypingExtensions,
+}
+
+impl CoreStdlibModule {
+    fn name(self) -> ModuleName {
+        let module_name = match self {
+            Self::Builtins => "builtins",
+            Self::Types => "types",
+            Self::Typeshed => "_typeshed",
+            Self::TypingExtensions => "typing_extensions",
+        };
+        ModuleName::new_static(module_name)
+            .unwrap_or_else(|| panic!("{module_name} should be a valid module name!"))
+    }
+}
+
+/// Lookup the type of `symbol` in a given core module
+///
+/// Returns `Unbound` if the given core module cannot be resolved for some reason
+fn core_module_symbol_ty<'db>(
+    db: &'db dyn Db,
+    core_module: CoreStdlibModule,
+    symbol: &str,
+) -> Type<'db> {
+    resolve_module(db, core_module.name())
+        .map(|module| global_symbol_ty(db, module.file(), symbol))
+        .unwrap_or(Type::Unbound)
+}
+
+/// Lookup the type of `symbol` in the builtins namespace.
+///
+/// Returns `Unbound` if the `builtins` module isn't available for some reason.
+#[inline]
+pub(crate) fn builtins_symbol_ty<'db>(db: &'db dyn Db, symbol: &str) -> Type<'db> {
+    core_module_symbol_ty(db, CoreStdlibModule::Builtins, symbol)
+}
+
+/// Lookup the type of `symbol` in the `types` module namespace.
+///
+/// Returns `Unbound` if the `types` module isn't available for some reason.
+#[inline]
+pub(crate) fn types_symbol_ty<'db>(db: &'db dyn Db, symbol: &str) -> Type<'db> {
+    core_module_symbol_ty(db, CoreStdlibModule::Types, symbol)
+}
+
+/// Lookup the type of `symbol` in the `_typeshed` module namespace.
+///
+/// Returns `Unbound` if the `_typeshed` module isn't available for some reason.
+#[inline]
+pub(crate) fn typeshed_symbol_ty<'db>(db: &'db dyn Db, symbol: &str) -> Type<'db> {
+    core_module_symbol_ty(db, CoreStdlibModule::Typeshed, symbol)
+}
+
+/// Lookup the type of `symbol` in the `typing_extensions` module namespace.
+///
+/// Returns `Unbound` if the `typing_extensions` module isn't available for some reason.
+#[inline]
+pub(crate) fn typing_extensions_symbol_ty<'db>(db: &'db dyn Db, symbol: &str) -> Type<'db> {
+    core_module_symbol_ty(db, CoreStdlibModule::TypingExtensions, symbol)
+}
+
+/// Get the scope of a core stdlib module.
+///
+/// Can return `None` if a custom typeshed is used that is missing the core module in question.
+fn core_module_scope(db: &dyn Db, core_module: CoreStdlibModule) -> Option<ScopeId<'_>> {
+    resolve_module(db, core_module.name()).map(|module| global_scope(db, module.file()))
+}
+
+/// Get the `builtins` module scope.
+///
+/// Can return `None` if a custom typeshed is used that is missing `builtins.pyi`.
+pub(crate) fn builtins_module_scope(db: &dyn Db) -> Option<ScopeId<'_>> {
+    core_module_scope(db, CoreStdlibModule::Builtins)
+}
--- a/crates/red_knot_python_semantic/src/types.rs
+++ b/crates/red_knot_python_semantic/src/types.rs
--- a/crates/red_knot_python_semantic/src/types/builder.rs
+++ b/crates/red_knot_python_semantic/src/types/builder.rs
@@ -25,11 +25,12 @@
 //!   * No type in an intersection can be a supertype of any other type in the intersection (just
 //!     eliminate the supertype from the intersection).
 //!   * An intersection containing two non-overlapping types should simplify to [`Type::Never`].
-use crate::types::{IntersectionType, Type, UnionType};
+use crate::types::{builtins_symbol_ty, IntersectionType, Type, UnionType};
 use crate::{Db, FxOrderSet};
+use smallvec::SmallVec;

 pub(crate) struct UnionBuilder<'db> {
-    elements: FxOrderSet<Type<'db>>,
+    elements: Vec<Type<'db>>,
    db: &'db dyn Db,
 }

@@ -37,7 +38,7 @@ impl<'db> UnionBuilder<'db> {
    pub(crate) fn new(db: &'db dyn Db) -> Self {
        Self {
            db,
-            elements: FxOrderSet::default(),
+            elements: vec![],
        }
    }

@@ -45,11 +46,59 @@ impl<'db> UnionBuilder<'db> {
    pub(crate) fn add(mut self, ty: Type<'db>) -> Self {
        match ty {
            Type::Union(union) => {
-                self.elements.extend(&union.elements(self.db));
+                let new_elements = union.elements(self.db);
+                self.elements.reserve(new_elements.len());
+                for element in new_elements {
+                    self = self.add(*element);
+                }
            }
            Type::Never => {}
            _ => {
-                self.elements.insert(ty);
+                let bool_pair = if let Type::BooleanLiteral(b) = ty {
+                    Some(Type::BooleanLiteral(!b))
+                } else {
+                    None
+                };
+
+                let mut to_add = ty;
+                let mut to_remove = SmallVec::<[usize; 2]>::new();
+                for (index, element) in self.elements.iter().enumerate() {
+                    if Some(*element) == bool_pair {
+                        to_add = builtins_symbol_ty(self.db, "bool");
+                        to_remove.push(index);
+                        // The type we are adding is a BooleanLiteral, which doesn't have any
+                        // subtypes. And we just found that the union already contained our
+                        // mirror-image BooleanLiteral, so it can't also contain bool or any
+                        // supertype of bool. Therefore, we are done.
+                        break;
+                    }
+                    if ty.is_subtype_of(self.db, *element) {
+                        return self;
+                    } else if element.is_subtype_of(self.db, ty) {
+                        to_remove.push(index);
+                    }
+                }
+
+                match to_remove[..] {
+                    [] => self.elements.push(to_add),
+                    [index] => self.elements[index] = to_add,
+                    _ => {
+                        let mut current_index = 0;
+                        let mut to_remove = to_remove.into_iter();
+                        let mut next_to_remove_index = to_remove.next();
+                        self.elements.retain(|_| {
+                            let retain = if Some(current_index) == next_to_remove_index {
+                                next_to_remove_index = to_remove.next();
+                                false
+                            } else {
+                                true
+                            };
+                            current_index += 1;
+                            retain
+                        });
+                        self.elements.push(to_add);
+                    }
+                }
            }
        }

@@ -60,7 +109,7 @@ impl<'db> UnionBuilder<'db> {
        match self.elements.len() {
            0 => Type::Never,
            1 => self.elements[0],
-            _ => Type::Union(UnionType::new(self.db, self.elements)),
+            _ => Type::Union(UnionType::new(self.db, self.elements.into())),
        }
    }
 }
@@ -143,11 +192,12 @@ impl<'db> IntersectionBuilder<'db> {
        if self.intersections.len() == 1 {
            self.intersections.pop().unwrap().build(self.db)
        } else {
-            let mut builder = UnionBuilder::new(self.db);
-            for inner in self.intersections {
-                builder = builder.add(inner.build(self.db));
-            }
-            builder.build()
+            UnionType::from_elements(
+                self.db,
+                self.intersections
+                    .into_iter()
+                    .map(|inner| inner.build(self.db)),
+            )
        }
    }
 }
@@ -245,17 +295,32 @@ impl<'db> InnerIntersectionBuilder<'db> {

 #[cfg(test)]
 mod tests {
-    use super::{IntersectionBuilder, IntersectionType, Type, UnionBuilder, UnionType};
+    use super::{IntersectionBuilder, IntersectionType, Type, UnionType};
    use crate::db::tests::TestDb;
+    use crate::program::{Program, SearchPathSettings};
+    use crate::python_version::PythonVersion;
+    use crate::types::{builtins_symbol_ty, UnionBuilder};
+    use crate::ProgramSettings;
+    use ruff_db::system::{DbWithTestSystem, SystemPathBuf};

    fn setup_db() -> TestDb {
-        TestDb::new()
-    }
+        let db = TestDb::new();

-    impl<'db> UnionType<'db> {
-        fn elements_vec(self, db: &'db TestDb) -> Vec<Type<'db>> {
-            self.elements(db).into_iter().collect()
-        }
+        let src_root = SystemPathBuf::from("/src");
+        db.memory_file_system()
+            .create_directory_all(&src_root)
+            .unwrap();
+
+        Program::from_settings(
+            &db,
+            &ProgramSettings {
+                target_version: PythonVersion::default(),
+                search_paths: SearchPathSettings::new(src_root),
+            },
+        )
+        .expect("Valid search path settings");
+
+        db
    }

    #[test]
@@ -263,19 +328,16 @@ mod tests {
        let db = setup_db();
        let t0 = Type::IntLiteral(0);
        let t1 = Type::IntLiteral(1);
-        let Type::Union(union) = UnionBuilder::new(&db).add(t0).add(t1).build() else {
-            panic!("expected a union");
-        };
+        let union = UnionType::from_elements(&db, [t0, t1]).expect_union();

-        assert_eq!(union.elements_vec(&db), &[t0, t1]);
+        assert_eq!(union.elements(&db), &[t0, t1]);
    }

    #[test]
    fn build_union_single() {
        let db = setup_db();
        let t0 = Type::IntLiteral(0);
-        let ty = UnionBuilder::new(&db).add(t0).build();
-
+        let ty = UnionType::from_elements(&db, [t0]);
        assert_eq!(ty, t0);
    }

@@ -283,7 +345,6 @@ mod tests {
    fn build_union_empty() {
        let db = setup_db();
        let ty = UnionBuilder::new(&db).build();
-
        assert_eq!(ty, Type::Never);
    }

@@ -291,32 +352,83 @@ mod tests {
    fn build_union_never() {
        let db = setup_db();
        let t0 = Type::IntLiteral(0);
-        let ty = UnionBuilder::new(&db).add(t0).add(Type::Never).build();
-
+        let ty = UnionType::from_elements(&db, [t0, Type::Never]);
        assert_eq!(ty, t0);
    }

+    #[test]
+    fn build_union_bool() {
+        let db = setup_db();
+        let bool_ty = builtins_symbol_ty(&db, "bool");
+
+        let t0 = Type::BooleanLiteral(true);
+        let t1 = Type::BooleanLiteral(true);
+        let t2 = Type::BooleanLiteral(false);
+        let t3 = Type::IntLiteral(17);
+
+        let union = UnionType::from_elements(&db, [t0, t1, t3]).expect_union();
+        assert_eq!(union.elements(&db), &[t0, t3]);
+
+        let union = UnionType::from_elements(&db, [t0, t1, t2, t3]).expect_union();
+        assert_eq!(union.elements(&db), &[bool_ty, t3]);
+    }
+
    #[test]
    fn build_union_flatten() {
        let db = setup_db();
        let t0 = Type::IntLiteral(0);
        let t1 = Type::IntLiteral(1);
        let t2 = Type::IntLiteral(2);
-        let u1 = UnionBuilder::new(&db).add(t0).add(t1).build();
-        let Type::Union(union) = UnionBuilder::new(&db).add(u1).add(t2).build() else {
-            panic!("expected a union");
-        };
+        let u1 = UnionType::from_elements(&db, [t0, t1]);
+        let union = UnionType::from_elements(&db, [u1, t2]).expect_union();

-        assert_eq!(union.elements_vec(&db), &[t0, t1, t2]);
+        assert_eq!(union.elements(&db), &[t0, t1, t2]);
+    }
+
+    #[test]
+    fn build_union_simplify_subtype() {
+        let db = setup_db();
+        let t0 = builtins_symbol_ty(&db, "str").to_instance(&db);
+        let t1 = Type::LiteralString;
+        let u0 = UnionType::from_elements(&db, [t0, t1]);
+        let u1 = UnionType::from_elements(&db, [t1, t0]);
+
+        assert_eq!(u0, t0);
+        assert_eq!(u1, t0);
+    }
+
+    #[test]
+    fn build_union_no_simplify_unknown() {
+        let db = setup_db();
+        let t0 = builtins_symbol_ty(&db, "str").to_instance(&db);
+        let t1 = Type::Unknown;
+        let u0 = UnionType::from_elements(&db, [t0, t1]);
+        let u1 = UnionType::from_elements(&db, [t1, t0]);
+
+        assert_eq!(u0.expect_union().elements(&db), &[t0, t1]);
+        assert_eq!(u1.expect_union().elements(&db), &[t1, t0]);
+    }
+
+    #[test]
+    fn build_union_subsume_multiple() {
+        let db = setup_db();
+        let str_ty = builtins_symbol_ty(&db, "str").to_instance(&db);
+        let int_ty = builtins_symbol_ty(&db, "int").to_instance(&db);
+        let object_ty = builtins_symbol_ty(&db, "object").to_instance(&db);
+        let unknown_ty = Type::Unknown;
+
+        let u0 = UnionType::from_elements(&db, [str_ty, unknown_ty, int_ty, object_ty]);
+
+        assert_eq!(u0.expect_union().elements(&db), &[unknown_ty, object_ty]);
    }

    impl<'db> IntersectionType<'db> {
        fn pos_vec(self, db: &'db TestDb) -> Vec<Type<'db>> {
-            self.positive(db).into_iter().collect()
+            self.positive(db).into_iter().copied().collect()
        }

        fn neg_vec(self, db: &'db TestDb) -> Vec<Type<'db>> {
-            self.negative(db).into_iter().collect()
+            self.negative(db).into_iter().copied().collect()
        }
    }

@@ -325,16 +437,14 @@ mod tests {
        let db = setup_db();
        let t0 = Type::IntLiteral(0);
        let ta = Type::Any;
-        let Type::Intersection(inter) = IntersectionBuilder::new(&db)
+        let intersection = IntersectionBuilder::new(&db)
            .add_positive(ta)
            .add_negative(t0)
            .build()
-        else {
-            panic!("expected to be an intersection");
-        };
+            .expect_intersection();

-        assert_eq!(inter.pos_vec(&db), &[ta]);
-        assert_eq!(inter.neg_vec(&db), &[t0]);
+        assert_eq!(intersection.pos_vec(&db), &[ta]);
+        assert_eq!(intersection.neg_vec(&db), &[t0]);
    }

    #[test]
@@ -347,16 +457,14 @@ mod tests {
            .add_positive(ta)
            .add_negative(t1)
            .build();
-        let Type::Intersection(inter) = IntersectionBuilder::new(&db)
+        let intersection = IntersectionBuilder::new(&db)
            .add_positive(t2)
            .add_positive(i0)
            .build()
-        else {
-            panic!("expected to be an intersection");
-        };
+            .expect_intersection();

-        assert_eq!(inter.pos_vec(&db), &[t2, ta]);
-        assert_eq!(inter.neg_vec(&db), &[t1]);
+        assert_eq!(intersection.pos_vec(&db), &[t2, ta]);
+        assert_eq!(intersection.neg_vec(&db), &[t1]);
    }

    #[test]
@@ -369,16 +477,14 @@ mod tests {
            .add_positive(ta)
            .add_negative(t1)
            .build();
-        let Type::Intersection(inter) = IntersectionBuilder::new(&db)
+        let intersection = IntersectionBuilder::new(&db)
            .add_positive(t2)
            .add_negative(i0)
            .build()
-        else {
-            panic!("expected to be an intersection");
-        };
+            .expect_intersection();

-        assert_eq!(inter.pos_vec(&db), &[t2, t1]);
-        assert_eq!(inter.neg_vec(&db), &[ta]);
+        assert_eq!(intersection.pos_vec(&db), &[t2, t1]);
+        assert_eq!(intersection.neg_vec(&db), &[ta]);
    }

    #[test]
@@ -387,16 +493,14 @@ mod tests {
        let t0 = Type::IntLiteral(0);
        let t1 = Type::IntLiteral(1);
        let ta = Type::Any;
-        let u0 = UnionBuilder::new(&db).add(t0).add(t1).build();
+        let u0 = UnionType::from_elements(&db, [t0, t1]);

-        let Type::Union(union) = IntersectionBuilder::new(&db)
+        let union = IntersectionBuilder::new(&db)
            .add_positive(ta)
            .add_positive(u0)
            .build()
-        else {
-            panic!("expected a union");
-        };
-        let [Type::Intersection(i0), Type::Intersection(i1)] = union.elements_vec(&db)[..] else {
+            .expect_union();
+        let [Type::Intersection(i0), Type::Intersection(i1)] = union.elements(&db)[..] else {
            panic!("expected a union of two intersections");
        };
        assert_eq!(i0.pos_vec(&db), &[ta, t0]);
--- a/crates/red_knot_python_semantic/src/types/display.rs
+++ b/crates/red_knot_python_semantic/src/types/display.rs
@@ -1,17 +1,22 @@
 //! Display implementations for types.

-use std::fmt::{Display, Formatter};
+use std::fmt::{self, Display, Formatter};

+use ruff_db::display::FormatterJoinExtension;
 use ruff_python_ast::str::Quote;
 use ruff_python_literal::escape::AsciiEscape;

 use crate::types::{IntersectionType, Type, UnionType};
 use crate::Db;
+use rustc_hash::FxHashMap;

 impl<'db> Type<'db> {
-    pub fn display(&'db self, db: &'db dyn Db) -> DisplayType<'db> {
+    pub fn display(&self, db: &'db dyn Db) -> DisplayType {
        DisplayType { ty: self, db }
    }
+    fn representation(self, db: &'db dyn Db) -> DisplayRepresentation<'db> {
+        DisplayRepresentation { db, ty: self }
+    }
 }

 #[derive(Copy, Clone)]
@@ -21,7 +26,41 @@ pub struct DisplayType<'db> {
 }

 impl Display for DisplayType<'_> {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        let representation = self.ty.representation(self.db);
+        if matches!(
+            self.ty,
+            Type::IntLiteral(_)
+                | Type::BooleanLiteral(_)
+                | Type::StringLiteral(_)
+                | Type::BytesLiteral(_)
+                | Type::Class(_)
+                | Type::Function(_)
+                | Type::RevealTypeFunction(_)
+        ) {
+            write!(f, "Literal[{representation}]",)
+        } else {
+            representation.fmt(f)
+        }
+    }
+}
+
+impl fmt::Debug for DisplayType<'_> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        Display::fmt(self, f)
+    }
+}
+
+/// Writes the string representation of a type, which is the value displayed either as
+/// `Literal[<repr>]` or `Literal[<repr1>, <repr2>]` for literal types or as `<repr>` for
+/// non literals
+struct DisplayRepresentation<'db> {
+    ty: Type<'db>,
+    db: &'db dyn Db,
+}
+
+impl Display for DisplayRepresentation<'_> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
        match self.ty {
            Type::Any => f.write_str("Any"),
            Type::Never => f.write_str("Never"),
@@ -32,39 +71,39 @@ impl Display for DisplayType<'_> {
                write!(f, "<module '{:?}'>", file.path(self.db))
            }
            // TODO functions and classes should display using a fully qualified name
-            Type::Class(class) => write!(f, "Literal[{}]", class.name(self.db)),
-            Type::Instance(class) => f.write_str(&class.name(self.db)),
-            Type::Function(function) => write!(f, "Literal[{}]", function.name(self.db)),
+            Type::Class(class) => f.write_str(class.name(self.db)),
+            Type::Instance(class) => f.write_str(class.name(self.db)),
+            Type::Function(function) | Type::RevealTypeFunction(function) => {
+                f.write_str(function.name(self.db))
+            }
            Type::Union(union) => union.display(self.db).fmt(f),
            Type::Intersection(intersection) => intersection.display(self.db).fmt(f),
-            Type::IntLiteral(n) => write!(f, "Literal[{n}]"),
-            Type::BooleanLiteral(boolean) => {
-                write!(f, "Literal[{}]", if *boolean { "True" } else { "False" })
+            Type::IntLiteral(n) => n.fmt(f),
+            Type::BooleanLiteral(boolean) => f.write_str(if boolean { "True" } else { "False" }),
+            Type::StringLiteral(string) => {
+                write!(f, r#""{}""#, string.value(self.db).replace('"', r#"\""#))
            }
-            Type::StringLiteral(string) => write!(
-                f,
-                r#"Literal["{}"]"#,
-                string.value(self.db).replace('"', r#"\""#)
-            ),
-            Type::LiteralString => write!(f, "LiteralString"),
+            Type::LiteralString => f.write_str("LiteralString"),
            Type::BytesLiteral(bytes) => {
                let escape =
                    AsciiEscape::with_preferred_quote(bytes.value(self.db).as_ref(), Quote::Double);

-                f.write_str("Literal[")?;
-                escape.bytes_repr().write(f)?;
+                escape.bytes_repr().write(f)
+            }
+            Type::Tuple(tuple) => {
+                f.write_str("tuple[")?;
+                let elements = tuple.elements(self.db);
+                if elements.is_empty() {
+                    f.write_str("()")?;
+                } else {
+                    elements.display(self.db).fmt(f)?;
+                }
                f.write_str("]")
            }
        }
    }
 }

-impl std::fmt::Debug for DisplayType<'_> {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        std::fmt::Display::fmt(self, f)
-    }
-}
-
 impl<'db> UnionType<'db> {
    fn display(&'db self, db: &'db dyn Db) -> DisplayUnionType<'db> {
        DisplayUnionType { db, ty: self }
@@ -77,54 +116,90 @@ struct DisplayUnionType<'db> {
 }

 impl Display for DisplayUnionType<'_> {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        let union = self.ty;
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        let elements = self.ty.elements(self.db);

-        let (int_literals, other_types): (Vec<Type>, Vec<Type>) = union
-            .elements(self.db)
-            .iter()
-            .copied()
-            .partition(|ty| matches!(ty, Type::IntLiteral(_)));
+        // Group literal types by kind.
+        let mut grouped_literals = FxHashMap::default();

-        let mut first = true;
-        if !int_literals.is_empty() {
-            f.write_str("Literal[")?;
-            let mut nums: Vec<_> = int_literals
-                .into_iter()
-                .filter_map(|ty| {
-                    if let Type::IntLiteral(n) = ty {
-                        Some(n)
-                    } else {
-                        None
-                    }
-                })
-                .collect();
-            nums.sort_unstable();
-            for num in nums {
-                if !first {
-                    f.write_str(", ")?;
-                }
-                write!(f, "{num}")?;
-                first = false;
+        for element in elements {
+            if let Ok(literal_kind) = LiteralTypeKind::try_from(*element) {
+                grouped_literals
+                    .entry(literal_kind)
+                    .or_insert_with(Vec::new)
+                    .push(*element);
            }
-            f.write_str("]")?;
        }

-        for ty in other_types {
-            if !first {
-                f.write_str(" | ")?;
-            };
-            first = false;
-            write!(f, "{}", ty.display(self.db))?;
+        let mut join = f.join(" | ");
+
+        for element in elements {
+            if let Ok(literal_kind) = LiteralTypeKind::try_from(*element) {
+                let Some(mut literals) = grouped_literals.remove(&literal_kind) else {
+                    continue;
+                };
+                if literal_kind == LiteralTypeKind::IntLiteral {
+                    literals.sort_unstable_by_key(|ty| ty.expect_int_literal());
+                }
+                join.entry(&DisplayLiteralGroup {
+                    literals,
+                    db: self.db,
+                });
+            } else {
+                join.entry(&element.display(self.db));
+            }
        }

+        join.finish()?;
+
+        debug_assert!(grouped_literals.is_empty());
+
        Ok(())
    }
 }

-impl std::fmt::Debug for DisplayUnionType<'_> {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        std::fmt::Display::fmt(self, f)
+impl fmt::Debug for DisplayUnionType<'_> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        Display::fmt(self, f)
+    }
+}
+
+struct DisplayLiteralGroup<'db> {
+    literals: Vec<Type<'db>>,
+    db: &'db dyn Db,
+}
+
+impl Display for DisplayLiteralGroup<'_> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        f.write_str("Literal[")?;
+        f.join(", ")
+            .entries(self.literals.iter().map(|ty| ty.representation(self.db)))
+            .finish()?;
+        f.write_str("]")
+    }
+}
+
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
+enum LiteralTypeKind {
+    Class,
+    Function,
+    IntLiteral,
+    StringLiteral,
+    BytesLiteral,
+}
+
+impl TryFrom<Type<'_>> for LiteralTypeKind {
+    type Error = ();
+
+    fn try_from(value: Type<'_>) -> Result<Self, Self::Error> {
+        match value {
+            Type::Class(_) => Ok(Self::Class),
+            Type::Function(_) | Type::RevealTypeFunction(_) => Ok(Self::Function),
+            Type::IntLiteral(_) => Ok(Self::IntLiteral),
+            Type::StringLiteral(_) => Ok(Self::StringLiteral),
+            Type::BytesLiteral(_) => Ok(Self::BytesLiteral),
+            _ => Err(()),
+        }
    }
 }

@@ -140,30 +215,159 @@ struct DisplayIntersectionType<'db> {
 }

 impl Display for DisplayIntersectionType<'_> {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        let mut first = true;
-        for (neg, ty) in self
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        let tys = self
            .ty
            .positive(self.db)
            .iter()
-            .map(|ty| (false, ty))
-            .chain(self.ty.negative(self.db).iter().map(|ty| (true, ty)))
-        {
-            if !first {
-                f.write_str(" & ")?;
-            };
-            first = false;
-            if neg {
-                f.write_str("~")?;
-            };
-            write!(f, "{}", ty.display(self.db))?;
-        }
-        Ok(())
+            .map(|&ty| DisplayMaybeNegatedType {
+                ty,
+                db: self.db,
+                negated: false,
+            })
+            .chain(
+                self.ty
+                    .negative(self.db)
+                    .iter()
+                    .map(|&ty| DisplayMaybeNegatedType {
+                        ty,
+                        db: self.db,
+                        negated: true,
+                    }),
+            );
+        f.join(" & ").entries(tys).finish()
    }
 }

-impl std::fmt::Debug for DisplayIntersectionType<'_> {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        std::fmt::Display::fmt(self, f)
+impl fmt::Debug for DisplayIntersectionType<'_> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        Display::fmt(self, f)
+    }
+}
+
+struct DisplayMaybeNegatedType<'db> {
+    ty: Type<'db>,
+    db: &'db dyn Db,
+    negated: bool,
+}
+
+impl<'db> Display for DisplayMaybeNegatedType<'db> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        if self.negated {
+            f.write_str("~")?;
+        }
+        self.ty.display(self.db).fmt(f)
+    }
+}
+
+pub(crate) trait TypeArrayDisplay<'db> {
+    fn display(&self, db: &'db dyn Db) -> DisplayTypeArray;
+}
+
+impl<'db> TypeArrayDisplay<'db> for Box<[Type<'db>]> {
+    fn display(&self, db: &'db dyn Db) -> DisplayTypeArray {
+        DisplayTypeArray { types: self, db }
+    }
+}
+
+impl<'db> TypeArrayDisplay<'db> for Vec<Type<'db>> {
+    fn display(&self, db: &'db dyn Db) -> DisplayTypeArray {
+        DisplayTypeArray { types: self, db }
+    }
+}
+
+pub(crate) struct DisplayTypeArray<'b, 'db> {
+    types: &'b [Type<'db>],
+    db: &'db dyn Db,
+}
+
+impl<'db> Display for DisplayTypeArray<'_, 'db> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        f.join(", ")
+            .entries(self.types.iter().map(|ty| ty.display(self.db)))
+            .finish()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use ruff_db::files::system_path_to_file;
+    use ruff_db::system::{DbWithTestSystem, SystemPathBuf};
+
+    use crate::db::tests::TestDb;
+    use crate::types::{global_symbol_ty, BytesLiteralType, StringLiteralType, Type, UnionType};
+    use crate::{Program, ProgramSettings, PythonVersion, SearchPathSettings};
+
+    fn setup_db() -> TestDb {
+        let db = TestDb::new();
+
+        let src_root = SystemPathBuf::from("/src");
+        db.memory_file_system()
+            .create_directory_all(&src_root)
+            .unwrap();
+
+        Program::from_settings(
+            &db,
+            &ProgramSettings {
+                target_version: PythonVersion::default(),
+                search_paths: SearchPathSettings::new(src_root),
+            },
+        )
+        .expect("Valid search path settings");
+
+        db
+    }
+
+    #[test]
+    fn test_condense_literal_display_by_type() -> anyhow::Result<()> {
+        let mut db = setup_db();
+
+        db.write_dedented(
+            "src/main.py",
+            "
+            def foo(x: int) -> int:
+                return x + 1
+
+            def bar(s: str) -> str:
+                return s
+
+            class A: ...
+            class B: ...
+            ",
+        )?;
+        let mod_file = system_path_to_file(&db, "src/main.py").expect("Expected file to exist.");
+
+        let union_elements = &[
+            Type::Unknown,
+            Type::IntLiteral(-1),
+            global_symbol_ty(&db, mod_file, "A"),
+            Type::StringLiteral(StringLiteralType::new(&db, Box::from("A"))),
+            Type::BytesLiteral(BytesLiteralType::new(&db, Box::from([0]))),
+            Type::BytesLiteral(BytesLiteralType::new(&db, Box::from([7]))),
+            Type::IntLiteral(0),
+            Type::IntLiteral(1),
+            Type::StringLiteral(StringLiteralType::new(&db, Box::from("B"))),
+            global_symbol_ty(&db, mod_file, "foo"),
+            global_symbol_ty(&db, mod_file, "bar"),
+            global_symbol_ty(&db, mod_file, "B"),
+            Type::BooleanLiteral(true),
+            Type::None,
+        ];
+        let union = UnionType::from_elements(&db, union_elements).expect_union();
+        let display = format!("{}", union.display(&db));
+        assert_eq!(
+            display,
+            concat!(
+                "Unknown | ",
+                "Literal[-1, 0, 1] | ",
+                "Literal[A, B] | ",
+                "Literal[\"A\", \"B\"] | ",
+                "Literal[b\"\\x00\", b\"\\x07\"] | ",
+                "Literal[foo, bar] | ",
+                "Literal[True] | ",
+                "None"
+            )
+        );
+        Ok(())
    }
 }
--- a/crates/red_knot_python_semantic/src/types/infer.rs
+++ b/crates/red_knot_python_semantic/src/types/infer.rs
--- a/crates/red_knot_python_semantic/src/types/narrow.rs
+++ b/crates/red_knot_python_semantic/src/types/narrow.rs
@@ -1,9 +1,10 @@
 use crate::semantic_index::ast_ids::HasScopedAstId;
+use crate::semantic_index::constraint::{Constraint, PatternConstraint};
 use crate::semantic_index::definition::Definition;
 use crate::semantic_index::expression::Expression;
 use crate::semantic_index::symbol::{ScopeId, ScopedSymbolId, SymbolTable};
 use crate::semantic_index::symbol_table;
-use crate::types::{infer_expression_types, IntersectionBuilder, Type, TypeInference};
+use crate::types::{infer_expression_types, IntersectionBuilder, Type};
 use crate::Db;
 use ruff_python_ast as ast;
 use rustc_hash::FxHashMap;
@@ -27,62 +28,114 @@ use std::sync::Arc;
 /// constraint is applied to that definition, so we'd just return `None`.
 pub(crate) fn narrowing_constraint<'db>(
    db: &'db dyn Db,
-    test: Expression<'db>,
+    constraint: Constraint<'db>,
    definition: Definition<'db>,
 ) -> Option<Type<'db>> {
-    all_narrowing_constraints(db, test)
-        .get(&definition.symbol(db))
-        .copied()
+    match constraint {
+        Constraint::Expression(expression) => {
+            all_narrowing_constraints_for_expression(db, expression)
+                .get(&definition.symbol(db))
+                .copied()
+        }
+        Constraint::Pattern(pattern) => all_narrowing_constraints_for_pattern(db, pattern)
+            .get(&definition.symbol(db))
+            .copied(),
+    }
 }

 #[salsa::tracked(return_ref)]
-fn all_narrowing_constraints<'db>(
+fn all_narrowing_constraints_for_pattern<'db>(
    db: &'db dyn Db,
-    test: Expression<'db>,
+    pattern: PatternConstraint<'db>,
 ) -> NarrowingConstraints<'db> {
-    NarrowingConstraintsBuilder::new(db, test).finish()
+    NarrowingConstraintsBuilder::new(db, Constraint::Pattern(pattern)).finish()
+}
+
+#[salsa::tracked(return_ref)]
+fn all_narrowing_constraints_for_expression<'db>(
+    db: &'db dyn Db,
+    expression: Expression<'db>,
+) -> NarrowingConstraints<'db> {
+    NarrowingConstraintsBuilder::new(db, Constraint::Expression(expression)).finish()
 }

 type NarrowingConstraints<'db> = FxHashMap<ScopedSymbolId, Type<'db>>;

 struct NarrowingConstraintsBuilder<'db> {
    db: &'db dyn Db,
-    expression: Expression<'db>,
+    constraint: Constraint<'db>,
    constraints: NarrowingConstraints<'db>,
 }

 impl<'db> NarrowingConstraintsBuilder<'db> {
-    fn new(db: &'db dyn Db, expression: Expression<'db>) -> Self {
+    fn new(db: &'db dyn Db, constraint: Constraint<'db>) -> Self {
        Self {
            db,
-            expression,
+            constraint,
            constraints: NarrowingConstraints::default(),
        }
    }

    fn finish(mut self) -> NarrowingConstraints<'db> {
-        if let ast::Expr::Compare(expr_compare) = self.expression.node_ref(self.db).node() {
-            self.add_expr_compare(expr_compare);
+        match self.constraint {
+            Constraint::Expression(expression) => self.evaluate_expression_constraint(expression),
+            Constraint::Pattern(pattern) => self.evaluate_pattern_constraint(pattern),
        }
-        // TODO other test expression kinds

        self.constraints.shrink_to_fit();
        self.constraints
    }

+    fn evaluate_expression_constraint(&mut self, expression: Expression<'db>) {
+        if let ast::Expr::Compare(expr_compare) = expression.node_ref(self.db).node() {
+            self.add_expr_compare(expr_compare, expression);
+        }
+        // TODO other test expression kinds
+    }
+
+    fn evaluate_pattern_constraint(&mut self, pattern: PatternConstraint<'db>) {
+        let subject = pattern.subject(self.db);
+
+        match pattern.pattern(self.db).node() {
+            ast::Pattern::MatchValue(_) => {
+                // TODO
+            }
+            ast::Pattern::MatchSingleton(singleton_pattern) => {
+                self.add_match_pattern_singleton(subject, singleton_pattern);
+            }
+            ast::Pattern::MatchSequence(_) => {
+                // TODO
+            }
+            ast::Pattern::MatchMapping(_) => {
+                // TODO
+            }
+            ast::Pattern::MatchClass(_) => {
+                // TODO
+            }
+            ast::Pattern::MatchStar(_) => {
+                // TODO
+            }
+            ast::Pattern::MatchAs(_) => {
+                // TODO
+            }
+            ast::Pattern::MatchOr(_) => {
+                // TODO
+            }
+        }
+    }
+
    fn symbols(&self) -> Arc<SymbolTable> {
        symbol_table(self.db, self.scope())
    }

    fn scope(&self) -> ScopeId<'db> {
-        self.expression.scope(self.db)
+        match self.constraint {
+            Constraint::Expression(expression) => expression.scope(self.db),
+            Constraint::Pattern(pattern) => pattern.scope(self.db),
+        }
    }

-    fn inference(&self) -> &'db TypeInference<'db> {
-        infer_expression_types(self.db, self.expression)
-    }
-
-    fn add_expr_compare(&mut self, expr_compare: &ast::ExprCompare) {
+    fn add_expr_compare(&mut self, expr_compare: &ast::ExprCompare, expression: Expression<'db>) {
        let ast::ExprCompare {
            range: _,
            left,
@@ -99,7 +152,7 @@ impl<'db> NarrowingConstraintsBuilder<'db> {
            // SAFETY: we should always have a symbol for every Name node.
            let symbol = self.symbols().symbol_id_by_name(id).unwrap();
            let scope = self.scope();
-            let inference = self.inference();
+            let inference = infer_expression_types(self.db, expression);
            for (op, comparator) in std::iter::zip(&**ops, &**comparators) {
                let comp_ty = inference.expression_ty(comparator.scoped_ast_id(self.db, scope));
                if matches!(op, ast::CmpOp::IsNot) {
@@ -112,4 +165,22 @@ impl<'db> NarrowingConstraintsBuilder<'db> {
            }
        }
    }
+
+    fn add_match_pattern_singleton(
+        &mut self,
+        subject: &ast::Expr,
+        pattern: &ast::PatternMatchSingleton,
+    ) {
+        if let Some(ast::ExprName { id, .. }) = subject.as_name_expr() {
+            // SAFETY: we should always have a symbol for every Name node.
+            let symbol = self.symbols().symbol_id_by_name(id).unwrap();
+
+            let ty = match pattern.value {
+                ast::Singleton::None => Type::None,
+                ast::Singleton::True => Type::BooleanLiteral(true),
+                ast::Singleton::False => Type::BooleanLiteral(false),
+            };
+            self.constraints.insert(symbol, ty);
+        }
+    }
 }
--- a/crates/red_knot_python_semantic/vendor/typeshed/source_commit.txt
+++ b/crates/red_knot_python_semantic/vendor/typeshed/source_commit.txt
@@ -1 +1 @@
-1ace5718deaf3041f8e3d1dc9c9e8a8e830e517f
+9e506eb5e8fc2823db8c60ad561b1145ff114947
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/VERSIONS
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/VERSIONS
@@ -41,7 +41,7 @@ _json: 3.0-
 _locale: 3.0-
 _lsprof: 3.0-
 _markupbase: 3.0-
-_msi: 3.0-
+_msi: 3.0-3.12
 _operator: 3.4-
 _osx_support: 3.0-
 _posixsubprocess: 3.2-
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_ast.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_ast.pyi
@@ -1,7 +1,7 @@
 import sys
 import typing_extensions
 from typing import Any, ClassVar, Generic, Literal, TypedDict, overload
-from typing_extensions import Unpack
+from typing_extensions import Self, Unpack

 PyCF_ONLY_AST: Literal[1024]
 PyCF_TYPE_COMMENTS: Literal[4096]
@@ -34,6 +34,9 @@ class AST:
    if sys.version_info >= (3, 13):
        _field_types: ClassVar[dict[str, Any]]

+    if sys.version_info >= (3, 14):
+        def __replace__(self) -> Self: ...
+
 class mod(AST): ...
 class type_ignore(AST): ...

@@ -44,6 +47,9 @@ class TypeIgnore(type_ignore):
    tag: str
    def __init__(self, lineno: int, tag: str) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, lineno: int = ..., tag: str = ...) -> Self: ...
+
 class FunctionType(mod):
    if sys.version_info >= (3, 10):
        __match_args__ = ("argtypes", "returns")
@@ -57,6 +63,9 @@ class FunctionType(mod):
    else:
        def __init__(self, argtypes: list[expr], returns: expr) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, argtypes: list[expr] = ..., returns: expr = ...) -> Self: ...
+
 class Module(mod):
    if sys.version_info >= (3, 10):
        __match_args__ = ("body", "type_ignores")
@@ -67,6 +76,9 @@ class Module(mod):
    else:
        def __init__(self, body: list[stmt], type_ignores: list[TypeIgnore]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, body: list[stmt] = ..., type_ignores: list[TypeIgnore] = ...) -> Self: ...
+
 class Interactive(mod):
    if sys.version_info >= (3, 10):
        __match_args__ = ("body",)
@@ -76,12 +88,18 @@ class Interactive(mod):
    else:
        def __init__(self, body: list[stmt]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, body: list[stmt] = ...) -> Self: ...
+
 class Expression(mod):
    if sys.version_info >= (3, 10):
        __match_args__ = ("body",)
    body: expr
    def __init__(self, body: expr) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, body: expr = ...) -> Self: ...
+
 class stmt(AST):
    lineno: int
    col_offset: int
@@ -89,6 +107,9 @@ class stmt(AST):
    end_col_offset: int | None
    def __init__(self, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class FunctionDef(stmt):
    if sys.version_info >= (3, 12):
        __match_args__ = ("name", "args", "body", "decorator_list", "returns", "type_comment", "type_params")
@@ -152,6 +173,19 @@ class FunctionDef(stmt):
            **kwargs: Unpack[_Attributes],
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            name: _Identifier = ...,
+            args: arguments = ...,
+            body: list[stmt] = ...,
+            decorator_list: list[expr] = ...,
+            returns: expr | None = ...,
+            type_comment: str | None = ...,
+            type_params: list[type_param] = ...,
+        ) -> Self: ...
+
 class AsyncFunctionDef(stmt):
    if sys.version_info >= (3, 12):
        __match_args__ = ("name", "args", "body", "decorator_list", "returns", "type_comment", "type_params")
@@ -215,6 +249,19 @@ class AsyncFunctionDef(stmt):
            **kwargs: Unpack[_Attributes],
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            name: _Identifier = ...,
+            args: arguments = ...,
+            body: list[stmt],
+            decorator_list: list[expr],
+            returns: expr | None,
+            type_comment: str | None,
+            type_params: list[type_param],
+        ) -> Self: ...
+
 class ClassDef(stmt):
    if sys.version_info >= (3, 12):
        __match_args__ = ("name", "bases", "keywords", "body", "decorator_list", "type_params")
@@ -260,12 +307,28 @@ class ClassDef(stmt):
            **kwargs: Unpack[_Attributes],
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            name: _Identifier,
+            bases: list[expr],
+            keywords: list[keyword],
+            body: list[stmt],
+            decorator_list: list[expr],
+            type_params: list[type_param],
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class Return(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value",)
    value: expr | None
    def __init__(self, value: expr | None = None, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, value: expr | None = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Delete(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("targets",)
@@ -275,6 +338,9 @@ class Delete(stmt):
    else:
        def __init__(self, targets: list[expr], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, targets: list[expr] = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Assign(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("targets", "value", "type_comment")
@@ -295,6 +361,11 @@ class Assign(stmt):
            self, targets: list[expr], value: expr, type_comment: str | None = None, **kwargs: Unpack[_Attributes]
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, targets: list[expr] = ..., value: expr = ..., type_comment: str | None = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class AugAssign(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("target", "op", "value")
@@ -305,6 +376,16 @@ class AugAssign(stmt):
        self, target: Name | Attribute | Subscript, op: operator, value: expr, **kwargs: Unpack[_Attributes]
    ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            target: Name | Attribute | Subscript = ...,
+            op: operator = ...,
+            value: expr = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class AnnAssign(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("target", "annotation", "value", "simple")
@@ -332,6 +413,17 @@ class AnnAssign(stmt):
        **kwargs: Unpack[_Attributes],
    ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            target: Name | Attribute | Subscript = ...,
+            annotation: expr = ...,
+            value: expr | None = ...,
+            simple: int = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class For(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("target", "iter", "body", "orelse", "type_comment")
@@ -361,6 +453,18 @@ class For(stmt):
            **kwargs: Unpack[_Attributes],
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            target: expr = ...,
+            iter: expr = ...,
+            body: list[stmt] = ...,
+            orelse: list[stmt] = ...,
+            type_comment: str | None = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class AsyncFor(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("target", "iter", "body", "orelse", "type_comment")
@@ -390,6 +494,18 @@ class AsyncFor(stmt):
            **kwargs: Unpack[_Attributes],
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            target: expr = ...,
+            iter: expr = ...,
+            body: list[stmt] = ...,
+            orelse: list[stmt] = ...,
+            type_comment: str | None = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class While(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("test", "body", "orelse")
@@ -403,6 +519,9 @@ class While(stmt):
    else:
        def __init__(self, test: expr, body: list[stmt], orelse: list[stmt], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, test: expr, body: list[stmt], orelse: list[stmt], **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class If(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("test", "body", "orelse")
@@ -416,6 +535,11 @@ class If(stmt):
    else:
        def __init__(self, test: expr, body: list[stmt], orelse: list[stmt], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, test: expr = ..., body: list[stmt] = ..., orelse: list[stmt] = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class With(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("items", "body", "type_comment")
@@ -435,6 +559,16 @@ class With(stmt):
            self, items: list[withitem], body: list[stmt], type_comment: str | None = None, **kwargs: Unpack[_Attributes]
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            items: list[withitem] = ...,
+            body: list[stmt] = ...,
+            type_comment: str | None = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class AsyncWith(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("items", "body", "type_comment")
@@ -454,6 +588,16 @@ class AsyncWith(stmt):
            self, items: list[withitem], body: list[stmt], type_comment: str | None = None, **kwargs: Unpack[_Attributes]
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            items: list[withitem] = ...,
+            body: list[stmt] = ...,
+            type_comment: str | None = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class Raise(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("exc", "cause")
@@ -461,6 +605,9 @@ class Raise(stmt):
    cause: expr | None
    def __init__(self, exc: expr | None = None, cause: expr | None = None, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, exc: expr | None = ..., cause: expr | None = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Try(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("body", "handlers", "orelse", "finalbody")
@@ -487,6 +634,17 @@ class Try(stmt):
            **kwargs: Unpack[_Attributes],
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            body: list[stmt] = ...,
+            handlers: list[ExceptHandler] = ...,
+            orelse: list[stmt] = ...,
+            finalbody: list[stmt] = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 if sys.version_info >= (3, 11):
    class TryStar(stmt):
        __match_args__ = ("body", "handlers", "orelse", "finalbody")
@@ -513,6 +671,17 @@ if sys.version_info >= (3, 11):
                **kwargs: Unpack[_Attributes],
            ) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self,
+                *,
+                body: list[stmt] = ...,
+                handlers: list[ExceptHandler] = ...,
+                orelse: list[stmt] = ...,
+                finalbody: list[stmt] = ...,
+                **kwargs: Unpack[_Attributes],
+            ) -> Self: ...
+
 class Assert(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("test", "msg")
@@ -520,6 +689,9 @@ class Assert(stmt):
    msg: expr | None
    def __init__(self, test: expr, msg: expr | None = None, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, test: expr, msg: expr | None, **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Import(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("names",)
@@ -529,6 +701,9 @@ class Import(stmt):
    else:
        def __init__(self, names: list[alias], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, names: list[alias] = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class ImportFrom(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("module", "names", "level")
@@ -550,6 +725,11 @@ class ImportFrom(stmt):
            self, module: str | None = None, *, names: list[alias], level: int, **kwargs: Unpack[_Attributes]
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, module: str | None = ..., names: list[alias] = ..., level: int = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class Global(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("names",)
@@ -559,6 +739,9 @@ class Global(stmt):
    else:
        def __init__(self, names: list[_Identifier], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, names: list[_Identifier], **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Nonlocal(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("names",)
@@ -568,12 +751,18 @@ class Nonlocal(stmt):
    else:
        def __init__(self, names: list[_Identifier], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, names: list[_Identifier] = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Expr(stmt):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value",)
    value: expr
    def __init__(self, value: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, value: expr = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Pass(stmt): ...
 class Break(stmt): ...
 class Continue(stmt): ...
@@ -585,6 +774,9 @@ class expr(AST):
    end_col_offset: int | None
    def __init__(self, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class BoolOp(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("op", "values")
@@ -595,6 +787,9 @@ class BoolOp(expr):
    else:
        def __init__(self, op: boolop, values: list[expr], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, op: boolop = ..., values: list[expr] = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class BinOp(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("left", "op", "right")
@@ -603,6 +798,11 @@ class BinOp(expr):
    right: expr
    def __init__(self, left: expr, op: operator, right: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, left: expr = ..., op: operator = ..., right: expr = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class UnaryOp(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("op", "operand")
@@ -610,6 +810,9 @@ class UnaryOp(expr):
    operand: expr
    def __init__(self, op: unaryop, operand: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, op: unaryop = ..., operand: expr = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Lambda(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("args", "body")
@@ -617,6 +820,9 @@ class Lambda(expr):
    body: expr
    def __init__(self, args: arguments, body: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, args: arguments = ..., body: expr = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class IfExp(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("test", "body", "orelse")
@@ -625,6 +831,11 @@ class IfExp(expr):
    orelse: expr
    def __init__(self, test: expr, body: expr, orelse: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, test: expr = ..., body: expr = ..., orelse: expr = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class Dict(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("keys", "values")
@@ -635,6 +846,11 @@ class Dict(expr):
    else:
        def __init__(self, keys: list[expr | None], values: list[expr], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, keys: list[expr | None] = ..., values: list[expr] = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class Set(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("elts",)
@@ -644,6 +860,9 @@ class Set(expr):
    else:
        def __init__(self, elts: list[expr], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, elts: list[expr] = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class ListComp(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("elt", "generators")
@@ -654,6 +873,11 @@ class ListComp(expr):
    else:
        def __init__(self, elt: expr, generators: list[comprehension], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, elt: expr = ..., generators: list[comprehension] = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class SetComp(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("elt", "generators")
@@ -664,6 +888,11 @@ class SetComp(expr):
    else:
        def __init__(self, elt: expr, generators: list[comprehension], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, elt: expr = ..., generators: list[comprehension] = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class DictComp(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("key", "value", "generators")
@@ -677,6 +906,11 @@ class DictComp(expr):
    else:
        def __init__(self, key: expr, value: expr, generators: list[comprehension], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, key: expr = ..., value: expr = ..., generators: list[comprehension] = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class GeneratorExp(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("elt", "generators")
@@ -687,24 +921,38 @@ class GeneratorExp(expr):
    else:
        def __init__(self, elt: expr, generators: list[comprehension], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, elt: expr = ..., generators: list[comprehension] = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class Await(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value",)
    value: expr
    def __init__(self, value: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, value: expr = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Yield(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value",)
    value: expr | None
    def __init__(self, value: expr | None = None, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, value: expr | None = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class YieldFrom(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value",)
    value: expr
    def __init__(self, value: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, value: expr = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Compare(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("left", "ops", "comparators")
@@ -718,6 +966,11 @@ class Compare(expr):
    else:
        def __init__(self, left: expr, ops: list[cmpop], comparators: list[expr], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, left: expr = ..., ops: list[cmpop] = ..., comparators: list[expr] = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class Call(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("func", "args", "keywords")
@@ -731,6 +984,11 @@ class Call(expr):
    else:
        def __init__(self, func: expr, args: list[expr], keywords: list[keyword], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, func: expr = ..., args: list[expr] = ..., keywords: list[keyword] = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class FormattedValue(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value", "conversion", "format_spec")
@@ -739,6 +997,11 @@ class FormattedValue(expr):
    format_spec: expr | None
    def __init__(self, value: expr, conversion: int, format_spec: expr | None = None, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, value: expr = ..., conversion: int = ..., format_spec: expr | None = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class JoinedStr(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("values",)
@@ -748,6 +1011,9 @@ class JoinedStr(expr):
    else:
        def __init__(self, values: list[expr], **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, values: list[expr] = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Constant(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value", "kind")
@@ -760,6 +1026,9 @@ class Constant(expr):

    def __init__(self, value: Any, kind: str | None = None, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, value: Any = ..., kind: str | None = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class NamedExpr(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("target", "value")
@@ -767,6 +1036,9 @@ class NamedExpr(expr):
    value: expr
    def __init__(self, target: Name, value: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, target: Name = ..., value: expr = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Attribute(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value", "attr", "ctx")
@@ -775,6 +1047,11 @@ class Attribute(expr):
    ctx: expr_context  # Not present in Python < 3.13 if not passed to `__init__`
    def __init__(self, value: expr, attr: _Identifier, ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, value: expr = ..., attr: _Identifier = ..., ctx: expr_context = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 if sys.version_info >= (3, 9):
    _Slice: typing_extensions.TypeAlias = expr
    _SliceAttributes: typing_extensions.TypeAlias = _Attributes
@@ -794,6 +1071,16 @@ class Slice(_Slice):
        self, lower: expr | None = None, upper: expr | None = None, step: expr | None = None, **kwargs: Unpack[_SliceAttributes]
    ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            lower: expr | None = ...,
+            upper: expr | None = ...,
+            step: expr | None = ...,
+            **kwargs: Unpack[_SliceAttributes],
+        ) -> Self: ...
+
 if sys.version_info < (3, 9):
    class ExtSlice(slice):
        dims: list[slice]
@@ -811,6 +1098,11 @@ class Subscript(expr):
    ctx: expr_context  # Not present in Python < 3.13 if not passed to `__init__`
    def __init__(self, value: expr, slice: _Slice, ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, value: expr = ..., slice: _Slice = ..., ctx: expr_context = ..., **kwargs: Unpack[_Attributes]
+        ) -> Self: ...
+
 class Starred(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("value", "ctx")
@@ -818,6 +1110,9 @@ class Starred(expr):
    ctx: expr_context  # Not present in Python < 3.13 if not passed to `__init__`
    def __init__(self, value: expr, ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, value: expr = ..., ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Name(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("id", "ctx")
@@ -825,6 +1120,9 @@ class Name(expr):
    ctx: expr_context  # Not present in Python < 3.13 if not passed to `__init__`
    def __init__(self, id: _Identifier, ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, id: _Identifier = ..., ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class List(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("elts", "ctx")
@@ -835,6 +1133,9 @@ class List(expr):
    else:
        def __init__(self, elts: list[expr], ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, elts: list[expr] = ..., ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class Tuple(expr):
    if sys.version_info >= (3, 10):
        __match_args__ = ("elts", "ctx")
@@ -847,6 +1148,9 @@ class Tuple(expr):
    else:
        def __init__(self, elts: list[expr], ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, elts: list[expr] = ..., ctx: expr_context = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class expr_context(AST): ...

 if sys.version_info < (3, 9):
@@ -910,6 +1214,9 @@ class comprehension(AST):
    else:
        def __init__(self, target: expr, iter: expr, ifs: list[expr], is_async: int) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, target: expr = ..., iter: expr = ..., ifs: list[expr] = ..., is_async: int = ...) -> Self: ...
+
 class excepthandler(AST):
    lineno: int
    col_offset: int
@@ -917,6 +1224,11 @@ class excepthandler(AST):
    end_col_offset: int | None
    def __init__(self, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self, *, lineno: int = ..., col_offset: int = ..., end_lineno: int | None = ..., end_col_offset: int | None = ...
+        ) -> Self: ...
+
 class ExceptHandler(excepthandler):
    if sys.version_info >= (3, 10):
        __match_args__ = ("type", "name", "body")
@@ -937,6 +1249,16 @@ class ExceptHandler(excepthandler):
            self, type: expr | None = None, name: _Identifier | None = None, *, body: list[stmt], **kwargs: Unpack[_Attributes]
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            type: expr | None = ...,
+            name: _Identifier | None = ...,
+            body: list[stmt] = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class arguments(AST):
    if sys.version_info >= (3, 10):
        __match_args__ = ("posonlyargs", "args", "vararg", "kwonlyargs", "kw_defaults", "kwarg", "defaults")
@@ -995,6 +1317,19 @@ class arguments(AST):
            defaults: list[expr],
        ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            posonlyargs: list[arg] = ...,
+            args: list[arg] = ...,
+            vararg: arg | None = ...,
+            kwonlyargs: list[arg] = ...,
+            kw_defaults: list[expr | None] = ...,
+            kwarg: arg | None = ...,
+            defaults: list[expr] = ...,
+        ) -> Self: ...
+
 class arg(AST):
    lineno: int
    col_offset: int
@@ -1009,6 +1344,16 @@ class arg(AST):
        self, arg: _Identifier, annotation: expr | None = None, type_comment: str | None = None, **kwargs: Unpack[_Attributes]
    ) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(
+            self,
+            *,
+            arg: _Identifier = ...,
+            annotation: expr | None = ...,
+            type_comment: str | None = ...,
+            **kwargs: Unpack[_Attributes],
+        ) -> Self: ...
+
 class keyword(AST):
    lineno: int
    col_offset: int
@@ -1023,6 +1368,9 @@ class keyword(AST):
    @overload
    def __init__(self, arg: _Identifier | None = None, *, value: expr, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, arg: _Identifier | None = ..., value: expr = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class alias(AST):
    lineno: int
    col_offset: int
@@ -1034,6 +1382,9 @@ class alias(AST):
    asname: _Identifier | None
    def __init__(self, name: str, asname: _Identifier | None = None, **kwargs: Unpack[_Attributes]) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, name: str = ..., asname: _Identifier | None = ..., **kwargs: Unpack[_Attributes]) -> Self: ...
+
 class withitem(AST):
    if sys.version_info >= (3, 10):
        __match_args__ = ("context_expr", "optional_vars")
@@ -1041,6 +1392,9 @@ class withitem(AST):
    optional_vars: expr | None
    def __init__(self, context_expr: expr, optional_vars: expr | None = None) -> None: ...

+    if sys.version_info >= (3, 14):
+        def __replace__(self, *, context_expr: expr = ..., optional_vars: expr | None = ...) -> Self: ...
+
 if sys.version_info >= (3, 10):
    class Match(stmt):
        __match_args__ = ("subject", "cases")
@@ -1051,6 +1405,11 @@ if sys.version_info >= (3, 10):
        else:
            def __init__(self, subject: expr, cases: list[match_case], **kwargs: Unpack[_Attributes]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self, *, subject: expr = ..., cases: list[match_case] = ..., **kwargs: Unpack[_Attributes]
+            ) -> Self: ...
+
    class pattern(AST):
        lineno: int
        col_offset: int
@@ -1058,6 +1417,11 @@ if sys.version_info >= (3, 10):
        end_col_offset: int
        def __init__(self, **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self, *, lineno: int = ..., col_offset: int = ..., end_lineno: int = ..., end_col_offset: int = ...
+            ) -> Self: ...
+
    # Without the alias, Pyright complains variables named pattern are recursively defined
    _Pattern: typing_extensions.TypeAlias = pattern

@@ -1074,16 +1438,25 @@ if sys.version_info >= (3, 10):
            @overload
            def __init__(self, pattern: _Pattern, guard: expr | None = None, *, body: list[stmt]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(self, *, pattern: _Pattern = ..., guard: expr | None = ..., body: list[stmt] = ...) -> Self: ...
+
    class MatchValue(pattern):
        __match_args__ = ("value",)
        value: expr
        def __init__(self, value: expr, **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(self, *, value: expr = ..., **kwargs: Unpack[_Attributes[int]]) -> Self: ...
+
    class MatchSingleton(pattern):
        __match_args__ = ("value",)
        value: Literal[True, False] | None
        def __init__(self, value: Literal[True, False] | None, **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(self, *, value: Literal[True, False] | None = ..., **kwargs: Unpack[_Attributes[int]]) -> Self: ...
+
    class MatchSequence(pattern):
        __match_args__ = ("patterns",)
        patterns: list[pattern]
@@ -1092,11 +1465,17 @@ if sys.version_info >= (3, 10):
        else:
            def __init__(self, patterns: list[pattern], **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(self, *, patterns: list[pattern] = ..., **kwargs: Unpack[_Attributes[int]]) -> Self: ...
+
    class MatchStar(pattern):
        __match_args__ = ("name",)
        name: _Identifier | None
        def __init__(self, name: _Identifier | None, **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(self, *, name: _Identifier | None = ..., **kwargs: Unpack[_Attributes[int]]) -> Self: ...
+
    class MatchMapping(pattern):
        __match_args__ = ("keys", "patterns", "rest")
        keys: list[expr]
@@ -1119,6 +1498,16 @@ if sys.version_info >= (3, 10):
                **kwargs: Unpack[_Attributes[int]],
            ) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self,
+                *,
+                keys: list[expr] = ...,
+                patterns: list[pattern] = ...,
+                rest: _Identifier | None = ...,
+                **kwargs: Unpack[_Attributes[int]],
+            ) -> Self: ...
+
    class MatchClass(pattern):
        __match_args__ = ("cls", "patterns", "kwd_attrs", "kwd_patterns")
        cls: expr
@@ -1144,6 +1533,17 @@ if sys.version_info >= (3, 10):
                **kwargs: Unpack[_Attributes[int]],
            ) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self,
+                *,
+                cls: expr = ...,
+                patterns: list[pattern] = ...,
+                kwd_attrs: list[_Identifier] = ...,
+                kwd_patterns: list[pattern] = ...,
+                **kwargs: Unpack[_Attributes[int]],
+            ) -> Self: ...
+
    class MatchAs(pattern):
        __match_args__ = ("pattern", "name")
        pattern: _Pattern | None
@@ -1152,6 +1552,11 @@ if sys.version_info >= (3, 10):
            self, pattern: _Pattern | None = None, name: _Identifier | None = None, **kwargs: Unpack[_Attributes[int]]
        ) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self, *, pattern: _Pattern | None = ..., name: _Identifier | None = ..., **kwargs: Unpack[_Attributes[int]]
+            ) -> Self: ...
+
    class MatchOr(pattern):
        __match_args__ = ("patterns",)
        patterns: list[pattern]
@@ -1160,6 +1565,9 @@ if sys.version_info >= (3, 10):
        else:
            def __init__(self, patterns: list[pattern], **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(self, *, patterns: list[pattern] = ..., **kwargs: Unpack[_Attributes[int]]) -> Self: ...
+
 if sys.version_info >= (3, 12):
    class type_param(AST):
        lineno: int
@@ -1168,6 +1576,9 @@ if sys.version_info >= (3, 12):
        end_col_offset: int
        def __init__(self, **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(self, **kwargs: Unpack[_Attributes[int]]) -> Self: ...
+
    class TypeVar(type_param):
        if sys.version_info >= (3, 13):
            __match_args__ = ("name", "bound", "default_value")
@@ -1187,6 +1598,16 @@ if sys.version_info >= (3, 12):
        else:
            def __init__(self, name: _Identifier, bound: expr | None = None, **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self,
+                *,
+                name: _Identifier = ...,
+                bound: expr | None = ...,
+                default_value: expr | None = ...,
+                **kwargs: Unpack[_Attributes[int]],
+            ) -> Self: ...
+
    class ParamSpec(type_param):
        if sys.version_info >= (3, 13):
            __match_args__ = ("name", "default_value")
@@ -1201,6 +1622,11 @@ if sys.version_info >= (3, 12):
        else:
            def __init__(self, name: _Identifier, **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self, *, name: _Identifier = ..., default_value: expr | None = ..., **kwargs: Unpack[_Attributes[int]]
+            ) -> Self: ...
+
    class TypeVarTuple(type_param):
        if sys.version_info >= (3, 13):
            __match_args__ = ("name", "default_value")
@@ -1215,6 +1641,11 @@ if sys.version_info >= (3, 12):
        else:
            def __init__(self, name: _Identifier, **kwargs: Unpack[_Attributes[int]]) -> None: ...

+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self, *, name: _Identifier = ..., default_value: expr | None = ..., **kwargs: Unpack[_Attributes[int]]
+            ) -> Self: ...
+
    class TypeAlias(stmt):
        __match_args__ = ("name", "type_params", "value")
        name: Name
@@ -1233,3 +1664,13 @@ if sys.version_info >= (3, 12):
            def __init__(
                self, name: Name, type_params: list[type_param], value: expr, **kwargs: Unpack[_Attributes[int]]
            ) -> None: ...
+
+        if sys.version_info >= (3, 14):
+            def __replace__(
+                self,
+                *,
+                name: Name = ...,
+                type_params: list[type_param] = ...,
+                value: expr = ...,
+                **kwargs: Unpack[_Attributes[int]],
+            ) -> Self: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_curses.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_curses.pyi
@@ -493,7 +493,7 @@ class _CursesWindow:
    def instr(self, y: int, x: int, n: int = ...) -> bytes: ...
    def is_linetouched(self, line: int, /) -> bool: ...
    def is_wintouched(self) -> bool: ...
-    def keypad(self, yes: bool) -> None: ...
+    def keypad(self, yes: bool, /) -> None: ...
    def leaveok(self, yes: bool) -> None: ...
    def move(self, new_y: int, new_x: int) -> None: ...
    def mvderwin(self, y: int, x: int) -> None: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_locale.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_locale.pyi
@@ -1,17 +1,38 @@
 import sys
 from _typeshed import StrPath
-from collections.abc import Mapping
+from typing import Final, Literal, TypedDict, type_check_only

-LC_CTYPE: int
-LC_COLLATE: int
-LC_TIME: int
-LC_MONETARY: int
-LC_NUMERIC: int
-LC_ALL: int
-CHAR_MAX: int
+@type_check_only
+class _LocaleConv(TypedDict):
+    decimal_point: str
+    grouping: list[int]
+    thousands_sep: str
+    int_curr_symbol: str
+    currency_symbol: str
+    p_cs_precedes: Literal[0, 1, 127]
+    n_cs_precedes: Literal[0, 1, 127]
+    p_sep_by_space: Literal[0, 1, 127]
+    n_sep_by_space: Literal[0, 1, 127]
+    mon_decimal_point: str
+    frac_digits: int
+    int_frac_digits: int
+    mon_thousands_sep: str
+    mon_grouping: list[int]
+    positive_sign: str
+    negative_sign: str
+    p_sign_posn: Literal[0, 1, 2, 3, 4, 127]
+    n_sign_posn: Literal[0, 1, 2, 3, 4, 127]
+
+LC_CTYPE: Final[int]
+LC_COLLATE: Final[int]
+LC_TIME: Final[int]
+LC_MONETARY: Final[int]
+LC_NUMERIC: Final[int]
+LC_ALL: Final[int]
+CHAR_MAX: Final = 127

 def setlocale(category: int, locale: str | None = None, /) -> str: ...
-def localeconv() -> Mapping[str, int | str | list[int]]: ...
+def localeconv() -> _LocaleConv: ...

 if sys.version_info >= (3, 11):
    def getencoding() -> str: ...
@@ -25,67 +46,67 @@ def strxfrm(string: str, /) -> str: ...
 if sys.platform != "win32":
    LC_MESSAGES: int

-    ABDAY_1: int
-    ABDAY_2: int
-    ABDAY_3: int
-    ABDAY_4: int
-    ABDAY_5: int
-    ABDAY_6: int
-    ABDAY_7: int
+    ABDAY_1: Final[int]
+    ABDAY_2: Final[int]
+    ABDAY_3: Final[int]
+    ABDAY_4: Final[int]
+    ABDAY_5: Final[int]
+    ABDAY_6: Final[int]
+    ABDAY_7: Final[int]

-    ABMON_1: int
-    ABMON_2: int
-    ABMON_3: int
-    ABMON_4: int
-    ABMON_5: int
-    ABMON_6: int
-    ABMON_7: int
-    ABMON_8: int
-    ABMON_9: int
-    ABMON_10: int
-    ABMON_11: int
-    ABMON_12: int
+    ABMON_1: Final[int]
+    ABMON_2: Final[int]
+    ABMON_3: Final[int]
+    ABMON_4: Final[int]
+    ABMON_5: Final[int]
+    ABMON_6: Final[int]
+    ABMON_7: Final[int]
+    ABMON_8: Final[int]
+    ABMON_9: Final[int]
+    ABMON_10: Final[int]
+    ABMON_11: Final[int]
+    ABMON_12: Final[int]

-    DAY_1: int
-    DAY_2: int
-    DAY_3: int
-    DAY_4: int
-    DAY_5: int
-    DAY_6: int
-    DAY_7: int
+    DAY_1: Final[int]
+    DAY_2: Final[int]
+    DAY_3: Final[int]
+    DAY_4: Final[int]
+    DAY_5: Final[int]
+    DAY_6: Final[int]
+    DAY_7: Final[int]

-    ERA: int
-    ERA_D_T_FMT: int
-    ERA_D_FMT: int
-    ERA_T_FMT: int
+    ERA: Final[int]
+    ERA_D_T_FMT: Final[int]
+    ERA_D_FMT: Final[int]
+    ERA_T_FMT: Final[int]

-    MON_1: int
-    MON_2: int
-    MON_3: int
-    MON_4: int
-    MON_5: int
-    MON_6: int
-    MON_7: int
-    MON_8: int
-    MON_9: int
-    MON_10: int
-    MON_11: int
-    MON_12: int
+    MON_1: Final[int]
+    MON_2: Final[int]
+    MON_3: Final[int]
+    MON_4: Final[int]
+    MON_5: Final[int]
+    MON_6: Final[int]
+    MON_7: Final[int]
+    MON_8: Final[int]
+    MON_9: Final[int]
+    MON_10: Final[int]
+    MON_11: Final[int]
+    MON_12: Final[int]

-    CODESET: int
-    D_T_FMT: int
-    D_FMT: int
-    T_FMT: int
-    T_FMT_AMPM: int
-    AM_STR: int
-    PM_STR: int
+    CODESET: Final[int]
+    D_T_FMT: Final[int]
+    D_FMT: Final[int]
+    T_FMT: Final[int]
+    T_FMT_AMPM: Final[int]
+    AM_STR: Final[int]
+    PM_STR: Final[int]

-    RADIXCHAR: int
-    THOUSEP: int
-    YESEXPR: int
-    NOEXPR: int
-    CRNCYSTR: int
-    ALT_DIGITS: int
+    RADIXCHAR: Final[int]
+    THOUSEP: Final[int]
+    YESEXPR: Final[int]
+    NOEXPR: Final[int]
+    CRNCYSTR: Final[int]
+    ALT_DIGITS: Final[int]

    def nl_langinfo(key: int, /) -> str: ...

--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_operator.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_operator.pyi
@@ -2,7 +2,7 @@ import sys
 from _typeshed import SupportsGetItem
 from collections.abc import Callable, Container, Iterable, MutableMapping, MutableSequence, Sequence
 from typing import Any, AnyStr, Generic, Protocol, SupportsAbs, SupportsIndex, TypeVar, final, overload
-from typing_extensions import ParamSpec, TypeAlias, TypeVarTuple, Unpack
+from typing_extensions import ParamSpec, TypeAlias, TypeIs, TypeVarTuple, Unpack

 _R = TypeVar("_R")
 _T = TypeVar("_T")
@@ -145,3 +145,7 @@ if sys.version_info >= (3, 11):
    def call(obj: Callable[_P, _R], /, *args: _P.args, **kwargs: _P.kwargs) -> _R: ...

 def _compare_digest(a: AnyStr, b: AnyStr, /) -> bool: ...
+
+if sys.version_info >= (3, 14):
+    def is_none(a: object, /) -> TypeIs[None]: ...
+    def is_not_none(a: _T | None, /) -> TypeIs[_T]: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_stat.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_stat.pyi
@@ -28,9 +28,9 @@ S_IFDIR: Final = 0o040000

 # These are 0 on systems that don't support the specific kind of file.
 # Example: Linux doesn't support door files, so S_IFDOOR is 0 on linux.
-S_IFDOOR: int
-S_IFPORT: int
-S_IFWHT: int
+S_IFDOOR: Final[int]
+S_IFPORT: Final[int]
+S_IFWHT: Final[int]

 S_ISUID: Final = 0o4000
 S_ISGID: Final = 0o2000
@@ -79,9 +79,9 @@ def S_ISWHT(mode: int, /) -> bool: ...
 def filemode(mode: int, /) -> str: ...

 if sys.platform == "win32":
-    IO_REPARSE_TAG_SYMLINK: int
-    IO_REPARSE_TAG_MOUNT_POINT: int
-    IO_REPARSE_TAG_APPEXECLINK: int
+    IO_REPARSE_TAG_SYMLINK: Final = 0xA000000C
+    IO_REPARSE_TAG_MOUNT_POINT: Final = 0xA0000003
+    IO_REPARSE_TAG_APPEXECLINK: Final = 0x8000001B

 if sys.platform == "win32":
    FILE_ATTRIBUTE_ARCHIVE: Final = 32
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_thread.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_thread.pyi
@@ -1,3 +1,4 @@
+import signal
 import sys
 from _typeshed import structseq
 from collections.abc import Callable
@@ -16,16 +17,39 @@ class LockType:
    def acquire(self, blocking: bool = True, timeout: float = -1) -> bool: ...
    def release(self) -> None: ...
    def locked(self) -> bool: ...
+    def acquire_lock(self, blocking: bool = True, timeout: float = -1) -> bool: ...
+    def release_lock(self) -> None: ...
+    def locked_lock(self) -> bool: ...
    def __enter__(self) -> bool: ...
    def __exit__(
        self, type: type[BaseException] | None, value: BaseException | None, traceback: TracebackType | None
    ) -> None: ...

+if sys.version_info >= (3, 13):
+    @final
+    class _ThreadHandle:
+        ident: int
+
+        def join(self, timeout: float | None = None, /) -> None: ...
+        def is_done(self) -> bool: ...
+        def _set_done(self) -> None: ...
+
+    def start_joinable_thread(
+        function: Callable[[], object], handle: _ThreadHandle | None = None, daemon: bool = True
+    ) -> _ThreadHandle: ...
+    lock = LockType
+
@overload
 def start_new_thread(function: Callable[[Unpack[_Ts]], object], args: tuple[Unpack[_Ts]], /) -> int: ...
@overload
 def start_new_thread(function: Callable[..., object], args: tuple[Any, ...], kwargs: dict[str, Any], /) -> int: ...
-def interrupt_main() -> None: ...
+
+if sys.version_info >= (3, 10):
+    def interrupt_main(signum: signal.Signals = ..., /) -> None: ...
+
+else:
+    def interrupt_main() -> None: ...
+
 def exit() -> NoReturn: ...
 def allocate_lock() -> LockType: ...
 def get_ident() -> int: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_tkinter.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_tkinter.pyi
@@ -106,8 +106,8 @@ EXCEPTION: Final = 8
 READABLE: Final = 2
 WRITABLE: Final = 4

-TCL_VERSION: str
-TK_VERSION: str
+TCL_VERSION: Final[str]
+TK_VERSION: Final[str]

@final
 class TkttType:
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_winapi.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/_winapi.pyi
@@ -99,6 +99,20 @@ if sys.platform == "win32":
    SEC_RESERVE: Final = 0x4000000
    SEC_WRITECOMBINE: Final = 0x40000000

+    if sys.version_info >= (3, 13):
+        STARTF_FORCEOFFFEEDBACK: Final = 0x80
+        STARTF_FORCEONFEEDBACK: Final = 0x40
+        STARTF_PREVENTPINNING: Final = 0x2000
+        STARTF_RUNFULLSCREEN: Final = 0x20
+        STARTF_TITLEISAPPID: Final = 0x1000
+        STARTF_TITLEISLINKNAME: Final = 0x800
+        STARTF_UNTRUSTEDSOURCE: Final = 0x8000
+        STARTF_USECOUNTCHARS: Final = 0x8
+        STARTF_USEFILLATTRIBUTE: Final = 0x10
+        STARTF_USEHOTKEY: Final = 0x200
+        STARTF_USEPOSITION: Final = 0x4
+        STARTF_USESIZE: Final = 0x2
+
    STARTF_USESHOWWINDOW: Final = 0x1
    STARTF_USESTDHANDLES: Final = 0x100

@@ -250,6 +264,20 @@ if sys.platform == "win32":
        def cancel(self) -> None: ...
        def getbuffer(self) -> bytes | None: ...

+    if sys.version_info >= (3, 13):
+        def BatchedWaitForMultipleObjects(
+            handle_seq: Sequence[int], wait_all: bool, milliseconds: int = 0xFFFFFFFF
+        ) -> list[int]: ...
+        def CreateEventW(security_attributes: int, manual_reset: bool, initial_state: bool, name: str | None) -> int: ...
+        def CreateMutexW(security_attributes: int, initial_owner: bool, name: str) -> int: ...
+        def GetLongPathName(path: str) -> str: ...
+        def GetShortPathName(path: str) -> str: ...
+        def OpenEventW(desired_access: int, inherit_handle: bool, name: str) -> int: ...
+        def OpenMutexW(desired_access: int, inherit_handle: bool, name: str) -> int: ...
+        def ReleaseMutex(mutex: int) -> None: ...
+        def ResetEvent(event: int) -> None: ...
+        def SetEvent(event: int) -> None: ...
+
    if sys.version_info >= (3, 12):
        def CopyFile2(existing_file_name: str, new_file_name: str, flags: int, progress_routine: int | None = None) -> int: ...
        def NeedCurrentDirectoryForExePath(exe_name: str, /) -> bool: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/builtins.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/builtins.pyi
@@ -1,3 +1,4 @@
+# ruff: noqa: PYI036 # This is the module declaring BaseException
 import _ast
 import _typeshed
 import sys
@@ -33,7 +34,8 @@ from collections.abc import Awaitable, Callable, Iterable, Iterator, MutableSet,
 from io import BufferedRandom, BufferedReader, BufferedWriter, FileIO, TextIOWrapper
 from types import CellType, CodeType, TracebackType

-# mypy crashes if any of {ByteString, Sequence, MutableSequence, Mapping, MutableMapping} are imported from collections.abc in builtins.pyi
+# mypy crashes if any of {ByteString, Sequence, MutableSequence, Mapping, MutableMapping}
+# are imported from collections.abc in builtins.pyi
 from typing import (  # noqa: Y022
    IO,
    Any,
@@ -967,7 +969,9 @@ class tuple(Sequence[_T_co]):
    if sys.version_info >= (3, 9):
        def __class_getitem__(cls, item: Any, /) -> GenericAlias: ...

-# Doesn't exist at runtime, but deleting this breaks mypy. See #2999
+# Doesn't exist at runtime, but deleting this breaks mypy and pyright. See:
+# https://github.com/python/typeshed/issues/7580
+# https://github.com/python/mypy/issues/8240
@final
@type_check_only
 class function:
@@ -1084,7 +1088,8 @@ class dict(MutableMapping[_KT, _VT]):
    def keys(self) -> dict_keys[_KT, _VT]: ...
    def values(self) -> dict_values[_KT, _VT]: ...
    def items(self) -> dict_items[_KT, _VT]: ...
-    # Signature of `dict.fromkeys` should be kept identical to `fromkeys` methods of `OrderedDict`/`ChainMap`/`UserDict` in `collections`
+    # Signature of `dict.fromkeys` should be kept identical to
+    # `fromkeys` methods of `OrderedDict`/`ChainMap`/`UserDict` in `collections`
    # TODO: the true signature of `dict.fromkeys` is not expressible in the current type system.
    # See #3800 & https://github.com/python/typing/issues/548#issuecomment-683336963.
    @classmethod
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/cmd.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/cmd.pyi
@@ -1,10 +1,11 @@
 from collections.abc import Callable
 from typing import IO, Any, Final
+from typing_extensions import LiteralString

 __all__ = ["Cmd"]

 PROMPT: Final = "(Cmd) "
-IDENTCHARS: str  # Too big to be `Literal`
+IDENTCHARS: Final[LiteralString]  # Too big to be `Literal`

 class Cmd:
    prompt: str
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/codecs.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/codecs.pyi
@@ -80,7 +80,7 @@ class _Encoder(Protocol):
    def __call__(self, input: str, errors: str = ..., /) -> tuple[bytes, int]: ...  # signature of Codec().encode

 class _Decoder(Protocol):
-    def __call__(self, input: bytes, errors: str = ..., /) -> tuple[str, int]: ...  # signature of Codec().decode
+    def __call__(self, input: ReadableBuffer, errors: str = ..., /) -> tuple[str, int]: ...  # signature of Codec().decode

 class _StreamReader(Protocol):
    def __call__(self, stream: _ReadableStream, errors: str = ..., /) -> StreamReader: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/collections/init.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/collections/init.pyi
@@ -345,15 +345,15 @@ class _OrderedDictValuesView(ValuesView[_VT_co], Reversible[_VT_co]):
 # but they are not exposed anywhere)
 # pyright doesn't have a specific error code for subclassing error!
@final
-class _odict_keys(dict_keys[_KT_co, _VT_co], Reversible[_KT_co]):  # type: ignore[misc]  # pyright: ignore
+class _odict_keys(dict_keys[_KT_co, _VT_co], Reversible[_KT_co]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
    def __reversed__(self) -> Iterator[_KT_co]: ...

@final
-class _odict_items(dict_items[_KT_co, _VT_co], Reversible[tuple[_KT_co, _VT_co]]):  # type: ignore[misc]  # pyright: ignore
+class _odict_items(dict_items[_KT_co, _VT_co], Reversible[tuple[_KT_co, _VT_co]]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
    def __reversed__(self) -> Iterator[tuple[_KT_co, _VT_co]]: ...

@final
-class _odict_values(dict_values[_KT_co, _VT_co], Reversible[_VT_co], Generic[_KT_co, _VT_co]):  # type: ignore[misc]  # pyright: ignore
+class _odict_values(dict_values[_KT_co, _VT_co], Reversible[_VT_co], Generic[_KT_co, _VT_co]):  # type: ignore[misc]  # pyright: ignore[reportGeneralTypeIssues]
    def __reversed__(self) -> Iterator[_VT_co]: ...

 class OrderedDict(dict[_KT, _VT], Reversible[_KT], Generic[_KT, _VT]):
@@ -475,7 +475,8 @@ class ChainMap(MutableMapping[_KT, _VT]):
    def pop(self, key: _KT, default: _T) -> _VT | _T: ...
    def copy(self) -> Self: ...
    __copy__ = copy
-    # All arguments to `fromkeys` are passed to `dict.fromkeys` at runtime, so the signature should be kept in line with `dict.fromkeys`.
+    # All arguments to `fromkeys` are passed to `dict.fromkeys` at runtime,
+    # so the signature should be kept in line with `dict.fromkeys`.
    @classmethod
    @overload
    def fromkeys(cls, iterable: Iterable[_T]) -> ChainMap[_T, Any | None]: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/copy.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/copy.pyi
@@ -1,16 +1,15 @@
 import sys
 from typing import Any, Protocol, TypeVar
-from typing_extensions import ParamSpec, Self
+from typing_extensions import Self

 __all__ = ["Error", "copy", "deepcopy"]

 _T = TypeVar("_T")
-_SR = TypeVar("_SR", bound=_SupportsReplace[Any])
-_P = ParamSpec("_P")
+_SR = TypeVar("_SR", bound=_SupportsReplace)

-class _SupportsReplace(Protocol[_P]):
+class _SupportsReplace(Protocol):
    # In reality doesn't support args, but there's no other great way to express this.
-    def __replace__(self, *args: _P.args, **kwargs: _P.kwargs) -> Self: ...
+    def __replace__(self, *args: Any, **kwargs: Any) -> Self: ...

 # None in CPython but non-None in Jython
 PyStringMap: Any
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/crypt.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/crypt.pyi
@@ -1,12 +1,13 @@
 import sys
+from typing import Final

 if sys.platform != "win32":
    class _Method: ...
-    METHOD_CRYPT: _Method
-    METHOD_MD5: _Method
-    METHOD_SHA256: _Method
-    METHOD_SHA512: _Method
-    METHOD_BLOWFISH: _Method
+    METHOD_CRYPT: Final[_Method]
+    METHOD_MD5: Final[_Method]
+    METHOD_SHA256: Final[_Method]
+    METHOD_SHA512: Final[_Method]
+    METHOD_BLOWFISH: Final[_Method]
    methods: list[_Method]
    def mksalt(method: _Method | None = None, *, rounds: int | None = None) -> str: ...
    def crypt(word: str, salt: str | _Method | None = None) -> str: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/ctypes/init.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/ctypes/init.pyi
@@ -185,3 +185,8 @@ if sys.version_info >= (3, 12):
    c_time_t: type[c_int32 | c_int64]  # alias for one or the other at runtime

 class py_object(_CanCastTo, _SimpleCData[_T]): ...
+
+if sys.version_info >= (3, 14):
+    class c_float_complex(_SimpleCData[complex]): ...
+    class c_double_complex(_SimpleCData[complex]): ...
+    class c_longdouble_complex(_SimpleCData[complex]): ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/dataclasses.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/dataclasses.pyi
@@ -229,18 +229,17 @@ if sys.version_info >= (3, 9):
 else:
    class _InitVarMeta(type):
        # Not used, instead `InitVar.__class_getitem__` is called.
-        # pyright ignore is needed because pyright (not unreasonably) thinks this
-        # is an invalid use of InitVar.
-        def __getitem__(self, params: Any) -> InitVar[Any]: ...  # pyright: ignore
+        # pyright (not unreasonably) thinks this is an invalid use of InitVar.
+        def __getitem__(self, params: Any) -> InitVar[Any]: ...  # pyright: ignore[reportInvalidTypeForm]

 class InitVar(Generic[_T], metaclass=_InitVarMeta):
    type: Type[_T]
    def __init__(self, type: Type[_T]) -> None: ...
    if sys.version_info >= (3, 9):
        @overload
-        def __class_getitem__(cls, type: Type[_T]) -> InitVar[_T]: ...  # pyright: ignore
+        def __class_getitem__(cls, type: Type[_T]) -> InitVar[_T]: ...  # pyright: ignore[reportInvalidTypeForm]
        @overload
-        def __class_getitem__(cls, type: Any) -> InitVar[Any]: ...  # pyright: ignore
+        def __class_getitem__(cls, type: Any) -> InitVar[Any]: ...  # pyright: ignore[reportInvalidTypeForm]

 if sys.version_info >= (3, 12):
    def make_dataclass(
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/datetime.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/datetime.pyi
@@ -265,12 +265,12 @@ class datetime(date):
        def fromtimestamp(cls, timestamp: float, /, tz: _TzInfo | None = ...) -> Self: ...

    @classmethod
-    @deprecated("Use timezone-aware objects to represent datetimes in UTC; e.g. by calling .fromtimestamp(datetime.UTC)")
+    @deprecated("Use timezone-aware objects to represent datetimes in UTC; e.g. by calling .fromtimestamp(datetime.timezone.utc)")
    def utcfromtimestamp(cls, t: float, /) -> Self: ...
    @classmethod
    def now(cls, tz: _TzInfo | None = None) -> Self: ...
    @classmethod
-    @deprecated("Use timezone-aware objects to represent datetimes in UTC; e.g. by calling .now(datetime.UTC)")
+    @deprecated("Use timezone-aware objects to represent datetimes in UTC; e.g. by calling .now(datetime.timezone.utc)")
    def utcnow(cls) -> Self: ...
    @classmethod
    def combine(cls, date: _Date, time: _Time, tzinfo: _TzInfo | None = ...) -> Self: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/cmd.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/cmd.pyi
@@ -30,6 +30,7 @@ _CommandT = TypeVar("_CommandT", bound=Command)
 _Ts = TypeVarTuple("_Ts")

 class Command:
+    dry_run: Literal[0, 1]  # Exposed from __getattr_. Same as Distribution.dry_run
    distribution: Distribution
    # Any to work around variance issues
    sub_commands: ClassVar[list[tuple[str, Callable[[Any], bool] | None]]]
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/command/check.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/command/check.pyi
@@ -1,4 +1,4 @@
-from typing import Any, ClassVar, Literal
+from typing import Any, ClassVar, Final, Literal
 from typing_extensions import TypeAlias

 from ..cmd import Command
@@ -22,7 +22,7 @@ class SilentReporter(_Reporter):
    ) -> None: ...
    def system_message(self, level, message, *children, **kwargs): ...

-HAS_DOCUTILS: bool
+HAS_DOCUTILS: Final[bool]

 class check(Command):
    description: str
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/command/config.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/command/config.pyi
@@ -1,12 +1,12 @@
 from _typeshed import StrOrBytesPath
 from collections.abc import Sequence
 from re import Pattern
-from typing import Any, ClassVar, Literal
+from typing import Any, ClassVar, Final, Literal

 from ..ccompiler import CCompiler
 from ..cmd import Command

-LANG_EXT: dict[str, str]
+LANG_EXT: Final[dict[str, str]]

 class config(Command):
    description: str
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/command/install.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/command/install.pyi
@@ -1,11 +1,16 @@
+import sys
 from collections.abc import Callable
-from typing import Any, ClassVar
+from typing import Any, ClassVar, Final, Literal

 from ..cmd import Command

-HAS_USER_SITE: bool
-SCHEME_KEYS: tuple[str, ...]
-INSTALL_SCHEMES: dict[str, dict[Any, Any]]
+HAS_USER_SITE: Final[bool]
+
+SCHEME_KEYS: Final[tuple[Literal["purelib"], Literal["platlib"], Literal["headers"], Literal["scripts"], Literal["data"]]]
+INSTALL_SCHEMES: Final[dict[str, dict[str, str]]]
+
+if sys.version_info < (3, 10):
+    WINDOWS_SCHEME: Final[dict[str, str]]

 class install(Command):
    description: str
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/command/install_lib.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/command/install_lib.pyi
@@ -1,8 +1,8 @@
-from typing import Any, ClassVar
+from typing import Any, ClassVar, Final

 from ..cmd import Command

-PYTHON_SOURCE_EXTENSION: str
+PYTHON_SOURCE_EXTENSION: Final = ".py"

 class install_lib(Command):
    description: str
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/core.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/core.pyi
@@ -3,9 +3,9 @@ from collections.abc import Mapping
 from distutils.cmd import Command as Command
 from distutils.dist import Distribution as Distribution
 from distutils.extension import Extension as Extension
-from typing import Any, Literal
+from typing import Any, Final, Literal

-USAGE: str
+USAGE: Final[str]

 def gen_usage(script_name: StrOrBytesPath) -> str: ...

--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/cygwinccompiler.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/cygwinccompiler.pyi
@@ -1,20 +1,20 @@
 from distutils.unixccompiler import UnixCCompiler
 from distutils.version import LooseVersion
 from re import Pattern
-from typing import Literal
+from typing import Final, Literal

 def get_msvcr() -> list[str] | None: ...

 class CygwinCCompiler(UnixCCompiler): ...
 class Mingw32CCompiler(CygwinCCompiler): ...

-CONFIG_H_OK: str
-CONFIG_H_NOTOK: str
-CONFIG_H_UNCERTAIN: str
+CONFIG_H_OK: Final = "ok"
+CONFIG_H_NOTOK: Final = "not ok"
+CONFIG_H_UNCERTAIN: Final = "uncertain"

 def check_config_h() -> tuple[Literal["ok", "not ok", "uncertain"], str]: ...

-RE_VERSION: Pattern[bytes]
+RE_VERSION: Final[Pattern[bytes]]

 def get_versions() -> tuple[LooseVersion | None, ...]: ...
 def is_cygwingcc() -> bool: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/debug.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/debug.pyi
@@ -1 +1,3 @@
-DEBUG: bool | None
+from typing import Final
+
+DEBUG: Final[str | None]
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/dist.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/dist.pyi
@@ -88,9 +88,9 @@ class Distribution:
    display_options: ClassVar[_OptionsList]
    display_option_names: ClassVar[list[str]]
    negative_opt: ClassVar[dict[str, str]]
-    verbose: int
-    dry_run: int
-    help: int
+    verbose: Literal[0, 1]
+    dry_run: Literal[0, 1]
+    help: Literal[0, 1]
    command_packages: list[str] | None
    script_name: str | None
    script_args: list[str] | None
@@ -270,7 +270,7 @@ class Distribution:
    def has_data_files(self) -> bool: ...
    def is_pure(self) -> bool: ...

-    # Getter methods generated in __init__
+    # Default getter methods generated in __init__ from self.metadata._METHOD_BASENAMES
    def get_name(self) -> str: ...
    def get_version(self) -> str: ...
    def get_fullname(self) -> str: ...
@@ -292,3 +292,26 @@ class Distribution:
    def get_requires(self) -> list[str]: ...
    def get_provides(self) -> list[str]: ...
    def get_obsoletes(self) -> list[str]: ...
+
+    # Default attributes generated in __init__ from self.display_option_names
+    help_commands: bool | Literal[0]
+    name: str | Literal[0]
+    version: str | Literal[0]
+    fullname: str | Literal[0]
+    author: str | Literal[0]
+    author_email: str | Literal[0]
+    maintainer: str | Literal[0]
+    maintainer_email: str | Literal[0]
+    contact: str | Literal[0]
+    contact_email: str | Literal[0]
+    url: str | Literal[0]
+    license: str | Literal[0]
+    licence: str | Literal[0]
+    description: str | Literal[0]
+    long_description: str | Literal[0]
+    platforms: str | list[str] | Literal[0]
+    classifiers: str | list[str] | Literal[0]
+    keywords: str | list[str] | Literal[0]
+    provides: list[str] | Literal[0]
+    requires: list[str] | Literal[0]
+    obsoletes: list[str] | Literal[0]
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/fancy_getopt.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/fancy_getopt.pyi
@@ -1,15 +1,15 @@
 from collections.abc import Iterable, Mapping
 from re import Pattern
-from typing import Any, overload
+from typing import Any, Final, overload
 from typing_extensions import TypeAlias

 _Option: TypeAlias = tuple[str, str | None, str]
 _GR: TypeAlias = tuple[list[str], OptionDummy]

-longopt_pat: str
-longopt_re: Pattern[str]
-neg_alias_re: Pattern[str]
-longopt_xlate: dict[int, int]
+longopt_pat: Final = r"[a-zA-Z](?:[a-zA-Z0-9-]*)"
+longopt_re: Final[Pattern[str]]
+neg_alias_re: Final[Pattern[str]]
+longopt_xlate: Final[dict[int, int]]

 class FancyGetopt:
    def __init__(self, option_table: list[_Option] | None = None) -> None: ...
@@ -25,7 +25,7 @@ def fancy_getopt(
    options: list[_Option], negative_opt: Mapping[_Option, _Option], object: Any, args: list[str] | None
 ) -> list[str] | _GR: ...

-WS_TRANS: dict[int, str]
+WS_TRANS: Final[dict[int, str]]

 def wrap_text(text: str, width: int) -> list[str]: ...
 def translate_longopt(opt: str) -> str: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/log.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/log.pyi
@@ -1,10 +1,10 @@
-from typing import Any
+from typing import Any, Final

-DEBUG: int
-INFO: int
-WARN: int
-ERROR: int
-FATAL: int
+DEBUG: Final = 1
+INFO: Final = 2
+WARN: Final = 3
+ERROR: Final = 4
+FATAL: Final = 5

 class Log:
    def __init__(self, threshold: int = 3) -> None: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/sysconfig.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/distutils/sysconfig.pyi
@@ -1,15 +1,15 @@
 import sys
 from collections.abc import Mapping
 from distutils.ccompiler import CCompiler
-from typing import Literal, overload
+from typing import Final, Literal, overload
 from typing_extensions import deprecated

-PREFIX: str
-EXEC_PREFIX: str
-BASE_PREFIX: str
-BASE_EXEC_PREFIX: str
-project_base: str
-python_build: bool
+PREFIX: Final[str]
+EXEC_PREFIX: Final[str]
+BASE_PREFIX: Final[str]
+BASE_EXEC_PREFIX: Final[str]
+project_base: Final[str]
+python_build: Final[bool]

 def expand_makefile_vars(s: str, vars: Mapping[str, str]) -> str: ...
@overload
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/doctest.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/doctest.pyi
@@ -1,9 +1,10 @@
+import sys
 import types
 import unittest
 from _typeshed import ExcInfo
 from collections.abc import Callable
-from typing import Any, NamedTuple
-from typing_extensions import TypeAlias
+from typing import Any, ClassVar, NamedTuple
+from typing_extensions import Self, TypeAlias

 __all__ = [
    "register_optionflag",
@@ -41,9 +42,22 @@ __all__ = [
    "debug",
 ]

-class TestResults(NamedTuple):
-    failed: int
-    attempted: int
+# MyPy errors on conditionals within named tuples.
+
+if sys.version_info >= (3, 13):
+    class TestResults(NamedTuple):
+        def __new__(cls, failed: int, attempted: int, *, skipped: int = 0) -> Self: ...  # type: ignore[misc]
+        skipped: int
+        failed: int
+        attempted: int
+        _fields: ClassVar = ("failed", "attempted")  # type: ignore[misc]
+        __match_args__ = ("failed", "attempted")  # type: ignore[misc]
+        __doc__: None  # type: ignore[misc]
+
+else:
+    class TestResults(NamedTuple):
+        failed: int
+        attempted: int

 OPTIONFLAGS_BY_NAME: dict[str, int]

@@ -134,6 +148,8 @@ class DocTestRunner:
    original_optionflags: int
    tries: int
    failures: int
+    if sys.version_info >= (3, 13):
+        skips: int
    test: DocTest
    def __init__(self, checker: OutputChecker | None = None, verbose: bool | None = None, optionflags: int = 0) -> None: ...
    def report_start(self, out: _Out, test: DocTest, example: Example) -> None: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/_header_value_parser.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/_header_value_parser.pyi
@@ -16,6 +16,10 @@ TOKEN_ENDS: Final[set[str]]
 ASPECIALS: Final[set[str]]
 ATTRIBUTE_ENDS: Final[set[str]]
 EXTENDED_ATTRIBUTE_ENDS: Final[set[str]]
+# Added in Python 3.8.20, 3.9.20, 3.10.15, 3.11.10, 3.12.5
+NLSET: Final[set[str]]
+# Added in Python 3.8.20, 3.9.20, 3.10.15, 3.11.10, 3.12.5
+SPECIALSNL: Final[set[str]]

 def quote_string(value: Any) -> str: ...

--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/_policybase.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/_policybase.pyi
@@ -3,12 +3,34 @@ from collections.abc import Callable
 from email.errors import MessageDefect
 from email.header import Header
 from email.message import Message
-from typing import Any
 from typing_extensions import Self

 class _PolicyBase:
-    def __add__(self, other: Any) -> Self: ...
-    def clone(self, **kw: Any) -> Self: ...
+    def __init__(
+        self,
+        *,
+        max_line_length: int | None = 78,
+        linesep: str = "\n",
+        cte_type: str = "8bit",
+        raise_on_defect: bool = False,
+        mangle_from_: bool = ...,  # default depends on sub-class
+        message_factory: Callable[[Policy], Message] | None = None,
+        # Added in Python 3.8.20, 3.9.20, 3.10.15, 3.11.10, 3.12.5
+        verify_generated_headers: bool = True,
+    ) -> None: ...
+    def clone(
+        self,
+        *,
+        max_line_length: int | None = ...,
+        linesep: str = ...,
+        cte_type: str = ...,
+        raise_on_defect: bool = ...,
+        mangle_from_: bool = ...,
+        message_factory: Callable[[Policy], Message] | None = ...,
+        # Added in Python 3.8.20, 3.9.20, 3.10.15, 3.11.10, 3.12.5
+        verify_generated_headers: bool = ...,
+    ) -> Self: ...
+    def __add__(self, other: Policy) -> Self: ...

 class Policy(_PolicyBase, metaclass=ABCMeta):
    max_line_length: int | None
@@ -17,16 +39,9 @@ class Policy(_PolicyBase, metaclass=ABCMeta):
    raise_on_defect: bool
    mangle_from_: bool
    message_factory: Callable[[Policy], Message] | None
-    def __init__(
-        self,
-        *,
-        max_line_length: int | None = 78,
-        linesep: str = "\n",
-        cte_type: str = "8bit",
-        raise_on_defect: bool = False,
-        mangle_from_: bool = False,
-        message_factory: Callable[[Policy], Message] | None = None,
-    ) -> None: ...
+    # Added in Python 3.8.20, 3.9.20, 3.10.15, 3.11.10, 3.12.5
+    verify_generated_headers: bool
+
    def handle_defect(self, obj: Message, defect: MessageDefect) -> None: ...
    def register_defect(self, obj: Message, defect: MessageDefect) -> None: ...
    def header_max_count(self, name: str) -> int | None: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/errors.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/errors.pyi
@@ -7,6 +7,9 @@ class BoundaryError(MessageParseError): ...
 class MultipartConversionError(MessageError, TypeError): ...
 class CharsetError(MessageError): ...

+# Added in Python 3.8.20, 3.9.20, 3.10.15, 3.11.10, 3.12.5
+class HeaderWriteError(MessageError): ...
+
 class MessageDefect(ValueError):
    def __init__(self, line: str | None = None) -> None: ...

--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/message.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/message.pyi
@@ -50,7 +50,8 @@ class Message(Generic[_HeaderT, _HeaderParamT]):
    def get_payload(self, i: None = None, *, decode: Literal[True]) -> _EncodedPayloadType | Any: ...
    @overload  # not multipart, IDEM but w/o kwarg
    def get_payload(self, i: None, decode: Literal[True]) -> _EncodedPayloadType | Any: ...
-    # If `charset=None` and payload supports both `encode` AND `decode`, then an invalid payload could be passed, but this is unlikely
+    # If `charset=None` and payload supports both `encode` AND `decode`,
+    # then an invalid payload could be passed, but this is unlikely
    # Not[_SupportsEncodeToPayload]
    @overload
    def set_payload(
@@ -146,7 +147,11 @@ class Message(Generic[_HeaderT, _HeaderParamT]):
 class MIMEPart(Message[_HeaderRegistryT, _HeaderRegistryParamT]):
    def __init__(self, policy: Policy | None = None) -> None: ...
    def get_body(self, preferencelist: Sequence[str] = ("related", "html", "plain")) -> MIMEPart[_HeaderRegistryT] | None: ...
-    def iter_attachments(self) -> Iterator[MIMEPart[_HeaderRegistryT]]: ...
+    def attach(self, payload: Self) -> None: ...  # type: ignore[override]
+    # The attachments are created via type(self) in the attach method. It's theoretically
+    # possible to sneak other attachment types into a MIMEPart instance, but could cause
+    # cause unforseen consequences.
+    def iter_attachments(self) -> Iterator[Self]: ...
    def iter_parts(self) -> Iterator[MIMEPart[_HeaderRegistryT]]: ...
    def get_content(self, *args: Any, content_manager: ContentManager | None = None, **kw: Any) -> Any: ...
    def set_content(self, *args: Any, content_manager: ContentManager | None = None, **kw: Any) -> None: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/utils.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/email/utils.pyi
@@ -30,20 +30,12 @@ _PDTZ: TypeAlias = tuple[int, int, int, int, int, int, int, int, int, int | None
 def quote(str: str) -> str: ...
 def unquote(str: str) -> str: ...

-if sys.version_info >= (3, 13):
-    def parseaddr(addr: str | list[str], *, strict: bool = True) -> tuple[str, str]: ...
-
-else:
-    def parseaddr(addr: str) -> tuple[str, str]: ...
-
+# `strict` parameter added in Python 3.8.20, 3.9.20, 3.10.15, 3.11.10, 3.12.5
+def parseaddr(addr: str | list[str], *, strict: bool = True) -> tuple[str, str]: ...
 def formataddr(pair: tuple[str | None, str], charset: str | Charset = "utf-8") -> str: ...

-if sys.version_info >= (3, 13):
-    def getaddresses(fieldvalues: Iterable[str], *, strict: bool = True) -> list[tuple[str, str]]: ...
-
-else:
-    def getaddresses(fieldvalues: Iterable[str]) -> list[tuple[str, str]]: ...
-
+# `strict` parameter added in Python 3.8.20, 3.9.20, 3.10.15, 3.11.10, 3.12.5
+def getaddresses(fieldvalues: Iterable[str], *, strict: bool = True) -> list[tuple[str, str]]: ...
@overload
 def parsedate(data: None) -> None: ...
@overload
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/ftplib.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/ftplib.pyi
@@ -86,7 +86,7 @@ class FTP:
    def makeport(self) -> socket: ...
    def makepasv(self) -> tuple[str, int]: ...
    def login(self, user: str = "", passwd: str = "", acct: str = "") -> str: ...
-    # In practice, `rest` rest can actually be anything whose str() is an integer sequence, so to make it simple we allow integers.
+    # In practice, `rest` can actually be anything whose str() is an integer sequence, so to make it simple we allow integers
    def ntransfercmd(self, cmd: str, rest: int | str | None = None) -> tuple[socket, int | None]: ...
    def transfercmd(self, cmd: str, rest: int | str | None = None) -> socket: ...
    def retrbinary(
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/io.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/io.pyi
@@ -84,7 +84,6 @@ class RawIOBase(IOBase):
    def read(self, size: int = -1, /) -> bytes | None: ...

 class BufferedIOBase(IOBase):
-    raw: RawIOBase  # This is not part of the BufferedIOBase API and may not exist on some implementations.
    def detach(self) -> RawIOBase: ...
    def readinto(self, buffer: WriteableBuffer, /) -> int: ...
    def write(self, buffer: ReadableBuffer, /) -> int: ...
@@ -119,11 +118,13 @@ class BytesIO(BufferedIOBase, BinaryIO):  # type: ignore[misc]  # incompatible d
    def read1(self, size: int | None = -1, /) -> bytes: ...

 class BufferedReader(BufferedIOBase, BinaryIO):  # type: ignore[misc]  # incompatible definitions of methods in the base classes
+    raw: RawIOBase
    def __enter__(self) -> Self: ...
    def __init__(self, raw: RawIOBase, buffer_size: int = ...) -> None: ...
    def peek(self, size: int = 0, /) -> bytes: ...

 class BufferedWriter(BufferedIOBase, BinaryIO):  # type: ignore[misc]  # incompatible definitions of writelines in the base classes
+    raw: RawIOBase
    def __enter__(self) -> Self: ...
    def __init__(self, raw: RawIOBase, buffer_size: int = ...) -> None: ...
    def write(self, buffer: ReadableBuffer, /) -> int: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/json/encoder.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/json/encoder.pyi
@@ -1,12 +1,12 @@
 from collections.abc import Callable, Iterator
 from re import Pattern
-from typing import Any
+from typing import Any, Final

-ESCAPE: Pattern[str]
-ESCAPE_ASCII: Pattern[str]
-HAS_UTF8: Pattern[bytes]
-ESCAPE_DCT: dict[str, str]
-INFINITY: float
+ESCAPE: Final[Pattern[str]]
+ESCAPE_ASCII: Final[Pattern[str]]
+HAS_UTF8: Final[Pattern[bytes]]
+ESCAPE_DCT: Final[dict[str, str]]
+INFINITY: Final[float]

 def py_encode_basestring(s: str) -> str: ...  # undocumented
 def py_encode_basestring_ascii(s: str) -> str: ...  # undocumented
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/operator.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/operator.pyi
@@ -61,6 +61,9 @@ __all__ = [
 if sys.version_info >= (3, 11):
    __all__ += ["call"]

+if sys.version_info >= (3, 14):
+    __all__ += ["is_none", "is_not_none"]
+
 __lt__ = lt
 __le__ = le
 __eq__ = eq
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/os/init.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/os/init.pyi
@@ -365,7 +365,9 @@ class stat_result(structseq[float], tuple[int, int, int, int, int, int, int, flo
    if sys.version_info >= (3, 12) and sys.platform == "win32":
        @property
        @deprecated(
-            "Use st_birthtime instead to retrieve the file creation time. In the future, this property will contain the last metadata change time."
+            """\
+Use st_birthtime instead to retrieve the file creation time. \
+In the future, this property will contain the last metadata change time."""
        )
        def st_ctime(self) -> float: ...
    else:
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/poplib.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/poplib.pyi
@@ -67,5 +67,6 @@ class POP3_SSL(POP3):
            timeout: float = ...,
            context: ssl.SSLContext | None = None,
        ) -> None: ...
-        # "context" is actually the last argument, but that breaks LSP and it doesn't really matter because all the arguments are ignored
+        # "context" is actually the last argument,
+        # but that breaks LSP and it doesn't really matter because all the arguments are ignored
        def stls(self, context: Any = None, keyfile: Any = None, certfile: Any = None) -> NoReturn: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/pyexpat/init.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/pyexpat/init.pyi
@@ -15,9 +15,9 @@ class ExpatError(Exception):
    offset: int

 error = ExpatError
-XML_PARAM_ENTITY_PARSING_NEVER: int
-XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE: int
-XML_PARAM_ENTITY_PARSING_ALWAYS: int
+XML_PARAM_ENTITY_PARSING_NEVER: Final = 0
+XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE: Final = 1
+XML_PARAM_ENTITY_PARSING_ALWAYS: Final = 2

 _Model: TypeAlias = tuple[int, int, str | None, tuple[Any, ...]]

--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/pyexpat/errors.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/pyexpat/errors.pyi
@@ -1,49 +1,51 @@
 import sys
+from typing import Final
+from typing_extensions import LiteralString

 codes: dict[str, int]
 messages: dict[int, str]

-XML_ERROR_ABORTED: str
-XML_ERROR_ASYNC_ENTITY: str
-XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF: str
-XML_ERROR_BAD_CHAR_REF: str
-XML_ERROR_BINARY_ENTITY_REF: str
-XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING: str
-XML_ERROR_DUPLICATE_ATTRIBUTE: str
-XML_ERROR_ENTITY_DECLARED_IN_PE: str
-XML_ERROR_EXTERNAL_ENTITY_HANDLING: str
-XML_ERROR_FEATURE_REQUIRES_XML_DTD: str
-XML_ERROR_FINISHED: str
-XML_ERROR_INCOMPLETE_PE: str
-XML_ERROR_INCORRECT_ENCODING: str
-XML_ERROR_INVALID_TOKEN: str
-XML_ERROR_JUNK_AFTER_DOC_ELEMENT: str
-XML_ERROR_MISPLACED_XML_PI: str
-XML_ERROR_NOT_STANDALONE: str
-XML_ERROR_NOT_SUSPENDED: str
-XML_ERROR_NO_ELEMENTS: str
-XML_ERROR_NO_MEMORY: str
-XML_ERROR_PARAM_ENTITY_REF: str
-XML_ERROR_PARTIAL_CHAR: str
-XML_ERROR_PUBLICID: str
-XML_ERROR_RECURSIVE_ENTITY_REF: str
-XML_ERROR_SUSPENDED: str
-XML_ERROR_SUSPEND_PE: str
-XML_ERROR_SYNTAX: str
-XML_ERROR_TAG_MISMATCH: str
-XML_ERROR_TEXT_DECL: str
-XML_ERROR_UNBOUND_PREFIX: str
-XML_ERROR_UNCLOSED_CDATA_SECTION: str
-XML_ERROR_UNCLOSED_TOKEN: str
-XML_ERROR_UNDECLARING_PREFIX: str
-XML_ERROR_UNDEFINED_ENTITY: str
-XML_ERROR_UNEXPECTED_STATE: str
-XML_ERROR_UNKNOWN_ENCODING: str
-XML_ERROR_XML_DECL: str
+XML_ERROR_ABORTED: Final[LiteralString]
+XML_ERROR_ASYNC_ENTITY: Final[LiteralString]
+XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF: Final[LiteralString]
+XML_ERROR_BAD_CHAR_REF: Final[LiteralString]
+XML_ERROR_BINARY_ENTITY_REF: Final[LiteralString]
+XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING: Final[LiteralString]
+XML_ERROR_DUPLICATE_ATTRIBUTE: Final[LiteralString]
+XML_ERROR_ENTITY_DECLARED_IN_PE: Final[LiteralString]
+XML_ERROR_EXTERNAL_ENTITY_HANDLING: Final[LiteralString]
+XML_ERROR_FEATURE_REQUIRES_XML_DTD: Final[LiteralString]
+XML_ERROR_FINISHED: Final[LiteralString]
+XML_ERROR_INCOMPLETE_PE: Final[LiteralString]
+XML_ERROR_INCORRECT_ENCODING: Final[LiteralString]
+XML_ERROR_INVALID_TOKEN: Final[LiteralString]
+XML_ERROR_JUNK_AFTER_DOC_ELEMENT: Final[LiteralString]
+XML_ERROR_MISPLACED_XML_PI: Final[LiteralString]
+XML_ERROR_NOT_STANDALONE: Final[LiteralString]
+XML_ERROR_NOT_SUSPENDED: Final[LiteralString]
+XML_ERROR_NO_ELEMENTS: Final[LiteralString]
+XML_ERROR_NO_MEMORY: Final[LiteralString]
+XML_ERROR_PARAM_ENTITY_REF: Final[LiteralString]
+XML_ERROR_PARTIAL_CHAR: Final[LiteralString]
+XML_ERROR_PUBLICID: Final[LiteralString]
+XML_ERROR_RECURSIVE_ENTITY_REF: Final[LiteralString]
+XML_ERROR_SUSPENDED: Final[LiteralString]
+XML_ERROR_SUSPEND_PE: Final[LiteralString]
+XML_ERROR_SYNTAX: Final[LiteralString]
+XML_ERROR_TAG_MISMATCH: Final[LiteralString]
+XML_ERROR_TEXT_DECL: Final[LiteralString]
+XML_ERROR_UNBOUND_PREFIX: Final[LiteralString]
+XML_ERROR_UNCLOSED_CDATA_SECTION: Final[LiteralString]
+XML_ERROR_UNCLOSED_TOKEN: Final[LiteralString]
+XML_ERROR_UNDECLARING_PREFIX: Final[LiteralString]
+XML_ERROR_UNDEFINED_ENTITY: Final[LiteralString]
+XML_ERROR_UNEXPECTED_STATE: Final[LiteralString]
+XML_ERROR_UNKNOWN_ENCODING: Final[LiteralString]
+XML_ERROR_XML_DECL: Final[LiteralString]
 if sys.version_info >= (3, 11):
-    XML_ERROR_RESERVED_PREFIX_XML: str
-    XML_ERROR_RESERVED_PREFIX_XMLNS: str
-    XML_ERROR_RESERVED_NAMESPACE_URI: str
-    XML_ERROR_INVALID_ARGUMENT: str
-    XML_ERROR_NO_BUFFER: str
-    XML_ERROR_AMPLIFICATION_LIMIT_BREACH: str
+    XML_ERROR_RESERVED_PREFIX_XML: Final[LiteralString]
+    XML_ERROR_RESERVED_PREFIX_XMLNS: Final[LiteralString]
+    XML_ERROR_RESERVED_NAMESPACE_URI: Final[LiteralString]
+    XML_ERROR_INVALID_ARGUMENT: Final[LiteralString]
+    XML_ERROR_NO_BUFFER: Final[LiteralString]
+    XML_ERROR_AMPLIFICATION_LIMIT_BREACH: Final[LiteralString]
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/pyexpat/model.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/pyexpat/model.pyi
@@ -1,11 +1,13 @@
-XML_CTYPE_ANY: int
-XML_CTYPE_CHOICE: int
-XML_CTYPE_EMPTY: int
-XML_CTYPE_MIXED: int
-XML_CTYPE_NAME: int
-XML_CTYPE_SEQ: int
+from typing import Final

-XML_CQUANT_NONE: int
-XML_CQUANT_OPT: int
-XML_CQUANT_PLUS: int
-XML_CQUANT_REP: int
+XML_CTYPE_ANY: Final = 2
+XML_CTYPE_EMPTY: Final = 1
+XML_CTYPE_MIXED: Final = 3
+XML_CTYPE_NAME: Final = 4
+XML_CTYPE_CHOICE: Final = 5
+XML_CTYPE_SEQ: Final = 6
+
+XML_CQUANT_NONE: Final = 0
+XML_CQUANT_OPT: Final = 1
+XML_CQUANT_REP: Final = 2
+XML_CQUANT_PLUS: Final = 3
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/socketserver.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/socketserver.pyi
@@ -3,8 +3,9 @@ import types
 from _socket import _Address, _RetAddress
 from _typeshed import ReadableBuffer
 from collections.abc import Callable
+from io import BufferedIOBase
 from socket import socket as _socket
-from typing import Any, BinaryIO, ClassVar
+from typing import Any, ClassVar
 from typing_extensions import Self, TypeAlias

 __all__ = [
@@ -158,11 +159,11 @@ class StreamRequestHandler(BaseRequestHandler):
    timeout: ClassVar[float | None]  # undocumented
    disable_nagle_algorithm: ClassVar[bool]  # undocumented
    connection: Any  # undocumented
-    rfile: BinaryIO
-    wfile: BinaryIO
+    rfile: BufferedIOBase
+    wfile: BufferedIOBase

 class DatagramRequestHandler(BaseRequestHandler):
-    packet: _socket  # undocumented
+    packet: bytes  # undocumented
    socket: _socket  # undocumented
-    rfile: BinaryIO
-    wfile: BinaryIO
+    rfile: BufferedIOBase
+    wfile: BufferedIOBase
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/subprocess.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/subprocess.pyi
@@ -2582,6 +2582,11 @@ else:
 def list2cmdline(seq: Iterable[StrOrBytesPath]) -> str: ...  # undocumented

 if sys.platform == "win32":
+    if sys.version_info >= (3, 13):
+        from _winapi import STARTF_FORCEOFFFEEDBACK, STARTF_FORCEONFEEDBACK
+
+        __all__ += ["STARTF_FORCEOFFFEEDBACK", "STARTF_FORCEONFEEDBACK"]
+
    class STARTUPINFO:
        def __init__(
            self,
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tempfile.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tempfile.pyi
@@ -253,11 +253,11 @@ class _TemporaryFileWrapper(IO[AnyStr]):
    def truncate(self, size: int | None = ...) -> int: ...
    def writable(self) -> bool: ...
    @overload
-    def write(self: _TemporaryFileWrapper[str], s: str) -> int: ...
+    def write(self: _TemporaryFileWrapper[str], s: str, /) -> int: ...
    @overload
-    def write(self: _TemporaryFileWrapper[bytes], s: ReadableBuffer) -> int: ...
+    def write(self: _TemporaryFileWrapper[bytes], s: ReadableBuffer, /) -> int: ...
    @overload
-    def write(self, s: AnyStr) -> int: ...
+    def write(self, s: AnyStr, /) -> int: ...
    @overload
    def writelines(self: _TemporaryFileWrapper[str], lines: Iterable[str]) -> None: ...
    @overload
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tkinter/constants.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tkinter/constants.pyi
@@ -1,12 +1,12 @@
 from typing import Final

 # These are not actually bools. See #4669
-NO: bool
-YES: bool
-TRUE: bool
-FALSE: bool
-ON: bool
-OFF: bool
+NO: Final[bool]
+YES: Final[bool]
+TRUE: Final[bool]
+FALSE: Final[bool]
+ON: Final[bool]
+OFF: Final[bool]
 N: Final = "n"
 S: Final = "s"
 W: Final = "w"
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tkinter/dialog.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tkinter/dialog.pyi
@@ -2,12 +2,12 @@ import sys
 from _typeshed import Incomplete
 from collections.abc import Mapping
 from tkinter import Widget
-from typing import Any
+from typing import Any, Final

 if sys.version_info >= (3, 9):
    __all__ = ["Dialog"]

-DIALOG_ICON: str
+DIALOG_ICON: Final = "questhead"

 class Dialog(Widget):
    widgetName: str
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tkinter/messagebox.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tkinter/messagebox.pyi
@@ -1,6 +1,6 @@
 import sys
 from tkinter.commondialog import Dialog
-from typing import ClassVar
+from typing import ClassVar, Final

 if sys.version_info >= (3, 9):
    __all__ = [
@@ -14,22 +14,22 @@ if sys.version_info >= (3, 9):
        "askretrycancel",
    ]

-ERROR: str
-INFO: str
-QUESTION: str
-WARNING: str
-ABORTRETRYIGNORE: str
-OK: str
-OKCANCEL: str
-RETRYCANCEL: str
-YESNO: str
-YESNOCANCEL: str
-ABORT: str
-RETRY: str
-IGNORE: str
-CANCEL: str
-YES: str
-NO: str
+ERROR: Final = "error"
+INFO: Final = "info"
+QUESTION: Final = "question"
+WARNING: Final = "warning"
+ABORTRETRYIGNORE: Final = "abortretryignore"
+OK: Final = "ok"
+OKCANCEL: Final = "okcancel"
+RETRYCANCEL: Final = "retrycancel"
+YESNO: Final = "yesno"
+YESNOCANCEL: Final = "yesnocancel"
+ABORT: Final = "abort"
+RETRY: Final = "retry"
+IGNORE: Final = "ignore"
+CANCEL: Final = "cancel"
+YES: Final = "yes"
+NO: Final = "no"

 class Message(Dialog):
    command: ClassVar[str]
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tkinter/ttk.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/tkinter/ttk.pyi
@@ -556,7 +556,9 @@ class Notebook(Widget):
        sticky: str = ...,  # consists of letters 'n', 's', 'w', 'e', no repeats, may be empty
        padding: _Padding = ...,
        text: str = ...,
-        image=...,  # Sequence of an image name, followed by zero or more (sequences of one or more state names followed by an image name)
+        # `image` is a sequence of an image name, followed by zero or more
+        # (sequences of one or more state names followed by an image name)
+        image=...,
        compound: tkinter._Compound = ...,
        underline: int = ...,
    ) -> None: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/typing.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/typing.pyi
@@ -2,7 +2,7 @@
 # ruff: noqa: F811
 # TODO: The collections import is required, otherwise mypy crashes.
 # https://github.com/python/mypy/issues/16744
-import collections  # noqa: F401  # pyright: ignore
+import collections  # noqa: F401  # pyright: ignore[reportUnusedImport]
 import sys
 import typing_extensions
 from _collections_abc import dict_items, dict_keys, dict_values
@@ -800,18 +800,12 @@ class IO(Iterator[AnyStr]):
    def writable(self) -> bool: ...
    @abstractmethod
    @overload
-    def write(self: IO[str], s: str, /) -> int: ...
-    @abstractmethod
-    @overload
    def write(self: IO[bytes], s: ReadableBuffer, /) -> int: ...
    @abstractmethod
    @overload
    def write(self, s: AnyStr, /) -> int: ...
    @abstractmethod
    @overload
-    def writelines(self: IO[str], lines: Iterable[str], /) -> None: ...
-    @abstractmethod
-    @overload
    def writelines(self: IO[bytes], lines: Iterable[ReadableBuffer], /) -> None: ...
    @abstractmethod
    @overload
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/unittest/runner.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/unittest/runner.pyi
@@ -2,36 +2,52 @@ import sys
 import unittest.case
 import unittest.result
 import unittest.suite
-from _typeshed import Incomplete
+from _typeshed import SupportsFlush, SupportsWrite
 from collections.abc import Callable, Iterable
-from typing import TextIO
-from typing_extensions import TypeAlias
+from typing import Any, Generic, Protocol, TypeVar
+from typing_extensions import Never, TypeAlias

-_ResultClassType: TypeAlias = Callable[[TextIO, bool, int], unittest.result.TestResult]
+_ResultClassType: TypeAlias = Callable[[_TextTestStream, bool, int], TextTestResult]

-class TextTestResult(unittest.result.TestResult):
+class _SupportsWriteAndFlush(SupportsWrite[str], SupportsFlush, Protocol): ...
+
+# All methods used by unittest.runner.TextTestResult's stream
+class _TextTestStream(_SupportsWriteAndFlush, Protocol):
+    def writeln(self, arg: str | None = None) -> str: ...
+
+# _WritelnDecorator should have all the same attrs as its stream param.
+# But that's not feasible to do Generically
+# We can expand the attributes if requested
+class _WritelnDecorator(_TextTestStream):
+    def __init__(self, stream: _TextTestStream) -> None: ...
+    def __getattr__(self, attr: str) -> Any: ...  # Any attribute from the stream type passed to __init__
+    # These attributes are prevented by __getattr__
+    stream: Never
+    __getstate__: Never
+
+_StreamT = TypeVar("_StreamT", bound=_TextTestStream, default=_WritelnDecorator)
+
+class TextTestResult(unittest.result.TestResult, Generic[_StreamT]):
    descriptions: bool  # undocumented
    dots: bool  # undocumented
    separator1: str
    separator2: str
    showAll: bool  # undocumented
-    stream: TextIO  # undocumented
+    stream: _StreamT  # undocumented
    if sys.version_info >= (3, 12):
        durations: unittest.result._DurationsType | None
        def __init__(
-            self, stream: TextIO, descriptions: bool, verbosity: int, *, durations: unittest.result._DurationsType | None = None
+            self, stream: _StreamT, descriptions: bool, verbosity: int, *, durations: unittest.result._DurationsType | None = None
        ) -> None: ...
    else:
-        def __init__(self, stream: TextIO, descriptions: bool, verbosity: int) -> None: ...
+        def __init__(self, stream: _StreamT, descriptions: bool, verbosity: int) -> None: ...

    def getDescription(self, test: unittest.case.TestCase) -> str: ...
    def printErrorList(self, flavour: str, errors: Iterable[tuple[unittest.case.TestCase, str]]) -> None: ...

 class TextTestRunner:
    resultclass: _ResultClassType
-    # TODO: add `_WritelnDecorator` type
-    # stream: _WritelnDecorator
-    stream: Incomplete
+    stream: _WritelnDecorator
    descriptions: bool
    verbosity: int
    failfast: bool
@@ -43,7 +59,7 @@ class TextTestRunner:
        durations: unittest.result._DurationsType | None
        def __init__(
            self,
-            stream: TextIO | None = None,
+            stream: _SupportsWriteAndFlush | None = None,
            descriptions: bool = True,
            verbosity: int = 1,
            failfast: bool = False,
@@ -57,7 +73,7 @@ class TextTestRunner:
    else:
        def __init__(
            self,
-            stream: TextIO | None = None,
+            stream: _SupportsWriteAndFlush | None = None,
            descriptions: bool = True,
            verbosity: int = 1,
            failfast: bool = False,
@@ -68,5 +84,5 @@ class TextTestRunner:
            tb_locals: bool = False,
        ) -> None: ...

-    def _makeResult(self) -> unittest.result.TestResult: ...
-    def run(self, test: unittest.suite.TestSuite | unittest.case.TestCase) -> unittest.result.TestResult: ...
+    def _makeResult(self) -> TextTestResult: ...
+    def run(self, test: unittest.suite.TestSuite | unittest.case.TestCase) -> TextTestResult: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/zipfile/init.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/zipfile/init.pyi
@@ -304,6 +304,7 @@ else:

    class Path:
        root: CompleteDirs
+        at: str
        def __init__(self, root: ZipFile | StrPath | IO[bytes], at: str = "") -> None: ...
        @property
        def name(self) -> str: ...
--- a/crates/red_knot_python_semantic/vendor/typeshed/stdlib/zipfile/_path.pyi
+++ b/crates/red_knot_python_semantic/vendor/typeshed/stdlib/zipfile/_path.pyi
@@ -31,6 +31,7 @@ if sys.version_info >= (3, 12):

    class Path:
        root: CompleteDirs
+        at: str
        def __init__(self, root: ZipFile | StrPath | IO[bytes], at: str = "") -> None: ...
        @property
        def name(self) -> str: ...
--- a/crates/red_knot_workspace/Cargo.toml
+++ b/crates/red_knot_workspace/Cargo.toml
@@ -29,6 +29,7 @@ tracing = { workspace = true }

 [dev-dependencies]
 ruff_db = { workspace = true, features = ["testing"] }
+tempfile = { workspace = true }

 [lints]
 workspace = true
--- a/crates/red_knot_workspace/resources/test/corpus/67_with_non_name_target.py
+++ b/crates/red_knot_workspace/resources/test/corpus/67_with_non_name_target.py
@@ -0,0 +1,2 @@
+with foo() as self.bar:
+    pass
--- a/crates/red_knot_workspace/src/lint.rs
+++ b/crates/red_knot_workspace/src/lint.rs
@@ -114,22 +114,19 @@ fn lint_maybe_undefined(context: &SemanticLintContext, name: &ast::ExprName) {
        return;
    }
    let semantic = &context.semantic;
-    match name.ty(semantic) {
-        Type::Unbound => {
-            context.push_diagnostic(format_diagnostic(
-                context,
-                &format!("Name '{}' used when not defined.", &name.id),
-                name.start(),
-            ));
-        }
-        Type::Union(union) if union.contains(semantic.db(), Type::Unbound) => {
-            context.push_diagnostic(format_diagnostic(
-                context,
-                &format!("Name '{}' used when possibly not defined.", &name.id),
-                name.start(),
-            ));
-        }
-        _ => {}
+    let ty = name.ty(semantic);
+    if ty.is_unbound() {
+        context.push_diagnostic(format_diagnostic(
+            context,
+            &format!("Name '{}' used when not defined.", &name.id),
+            name.start(),
+        ));
+    } else if ty.may_be_unbound(semantic.db()) {
+        context.push_diagnostic(format_diagnostic(
+            context,
+            &format!("Name '{}' used when possibly not defined.", &name.id),
+            name.start(),
+        ));
    }
 }

@@ -164,7 +161,7 @@ fn lint_bad_override(context: &SemanticLintContext, class: &ast::StmtClassDef) {
        if ty.has_decorator(db, override_ty) {
            let method_name = ty.name(db);
            if class_ty
-                .inherited_class_member(db, &method_name)
+                .inherited_class_member(db, method_name)
                .is_unbound()
            {
                // TODO should have a qualname() method to support nested classes
--- a/crates/red_knot_workspace/src/workspace.rs
+++ b/crates/red_knot_workspace/src/workspace.rs
@@ -297,7 +297,6 @@ impl Workspace {
    }
 }

-#[salsa::tracked]
 impl Package {
    pub fn root(self, db: &dyn Db) -> &SystemPath {
        self.root_buf(db)
--- a/crates/red_knot_workspace/tests/check.rs
+++ b/crates/red_knot_workspace/tests/check.rs
@@ -21,19 +21,27 @@ fn setup_db(workspace_root: &SystemPath) -> anyhow::Result<RootDatabase> {
 #[test]
 #[allow(clippy::print_stdout)]
 fn corpus_no_panic() -> anyhow::Result<()> {
-    let corpus = PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("resources/test/corpus");
-    let system_corpus =
-        SystemPathBuf::from_path_buf(corpus.clone()).expect("corpus path to be UTF8");
-    let db = setup_db(&system_corpus)?;
+    let root = SystemPathBuf::from_path_buf(tempfile::TempDir::new()?.into_path()).unwrap();
+    let db = setup_db(&root)?;

-    for path in fs::read_dir(&corpus).expect("corpus to be a directory") {
-        let path = path.expect("path to not be an error").path();
-        println!("checking {path:?}");
-        let path = SystemPathBuf::from_path_buf(path.clone()).expect("path to be UTF-8");
+    let corpus = PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("resources/test/corpus");
+
+    for path in fs::read_dir(&corpus)? {
+        let source = path?.path();
+        println!("checking {source:?}");
+        let source_fn = source.file_name().unwrap().to_str().unwrap();
+        let py_dest = root.join(source_fn);
+        fs::copy(&source, py_dest.as_std_path())?;
        // this test is only asserting that we can pull every expression type without a panic
        // (and some non-expressions that clearly define a single type)
-        let file = system_path_to_file(&db, path).expect("file to exist");
+        let file = system_path_to_file(&db, py_dest).unwrap();
+        pull_types(&db, file);

+        // try the file as a stub also
+        println!("re-checking as .pyi");
+        let pyi_dest = root.join(format!("{source_fn}i"));
+        std::fs::copy(source, pyi_dest.as_std_path())?;
+        let file = system_path_to_file(&db, pyi_dest).unwrap();
        pull_types(&db, file);
    }
    Ok(())
--- a/crates/ruff/Cargo.toml
+++ b/crates/ruff/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "ruff"
-version = "0.6.3"
+version = "0.6.6"
 publish = true
 authors = { workspace = true }
 edition = { workspace = true }
@@ -14,7 +14,9 @@ default-run = "ruff"

 [dependencies]
 ruff_cache = { workspace = true }
+ruff_db = { workspace = true }
 ruff_diagnostics = { workspace = true }
+ruff_graph = { workspace = true, features = ["serde", "clap"] }
 ruff_linter = { workspace = true, features = ["clap"] }
 ruff_macros = { workspace = true }
 ruff_notebook = { workspace = true }
@@ -36,6 +38,7 @@ clap_complete_command = { workspace = true }
 clearscreen = { workspace = true }
 colored = { workspace = true }
 filetime = { workspace = true }
+globwalk = { workspace = true }
 ignore = { workspace = true }
 is-macro = { workspace = true }
 itertools = { workspace = true }
@@ -59,8 +62,11 @@ wild = { workspace = true }
 [dev-dependencies]
 # Enable test rules during development
 ruff_linter = { workspace = true, features = ["clap", "test-rules"] }
+
+assert_fs = { workspace = true }
 # Avoid writing colored snapshots when running tests from the terminal
 colored = { workspace = true, features = ["no-color"] }
+indoc = { workspace = true }
 insta = { workspace = true, features = ["filters", "json"] }
 insta-cmd = { workspace = true }
 tempfile = { workspace = true }
--- a/crates/ruff/src/args.rs
+++ b/crates/ruff/src/args.rs
@@ -7,13 +7,11 @@ use std::sync::Arc;

 use anyhow::{anyhow, bail};
 use clap::builder::{TypedValueParser, ValueParserFactory};
-use clap::{command, Parser};
+use clap::{command, Parser, Subcommand};
 use colored::Colorize;
 use path_absolutize::path_dedot;
 use regex::Regex;
-use rustc_hash::FxHashMap;
-use toml;
-
+use ruff_graph::Direction;
 use ruff_linter::line_width::LineLength;
 use ruff_linter::logging::LogLevel;
 use ruff_linter::registry::Rule;
@@ -27,6 +25,8 @@ use ruff_text_size::TextRange;
 use ruff_workspace::configuration::{Configuration, RuleSelection};
 use ruff_workspace::options::{Options, PycodestyleOptions};
 use ruff_workspace::resolver::ConfigurationTransformer;
+use rustc_hash::FxHashMap;
+use toml;

 /// All configuration options that can be passed "globally",
 /// i.e., can be passed to all subcommands
@@ -132,6 +132,9 @@ pub enum Command {
    Format(FormatCommand),
    /// Run the language server.
    Server(ServerCommand),
+    /// Run analysis over Python source code.
+    #[clap(subcommand)]
+    Analyze(AnalyzeCommand),
    /// Display Ruff's version
    Version {
        #[arg(long, value_enum, default_value = "text")]
@@ -139,6 +142,35 @@ pub enum Command {
    },
 }

+#[derive(Debug, Subcommand)]
+pub enum AnalyzeCommand {
+    /// Generate a map of Python file dependencies or dependents.
+    Graph(AnalyzeGraphCommand),
+}
+
+#[derive(Clone, Debug, clap::Parser)]
+pub struct AnalyzeGraphCommand {
+    /// List of files or directories to include.
+    #[clap(help = "List of files or directories to include [default: .]")]
+    files: Vec<PathBuf>,
+    /// The direction of the import map. By default, generates a dependency map, i.e., a map from
+    /// file to files that it depends on. Use `--direction dependents` to generate a map from file
+    /// to files that depend on it.
+    #[clap(long, value_enum, default_value_t)]
+    direction: Direction,
+    /// Attempt to detect imports from string literals.
+    #[clap(long)]
+    detect_string_imports: bool,
+    /// Enable preview mode. Use `--no-preview` to disable.
+    #[arg(long, overrides_with("no_preview"))]
+    preview: bool,
+    #[clap(long, overrides_with("preview"), hide = true)]
+    no_preview: bool,
+    /// The minimum Python version that should be supported.
+    #[arg(long, value_enum)]
+    target_version: Option<PythonVersion>,
+}
+
 // The `Parser` derive is for ruff_dev, for ruff `Args` would be sufficient
 #[derive(Clone, Debug, clap::Parser)]
 #[allow(clippy::struct_excessive_bools)]
@@ -700,6 +732,7 @@ impl CheckCommand {
            output_format: resolve_output_format(self.output_format)?,
            show_fixes: resolve_bool_arg(self.show_fixes, self.no_show_fixes),
            extension: self.extension,
+            ..ExplicitConfigOverrides::default()
        };

        let config_args = ConfigArguments::from_cli_arguments(global_options, cli_overrides)?;
@@ -732,8 +765,34 @@ impl FormatCommand {
            target_version: self.target_version,
            cache_dir: self.cache_dir,
            extension: self.extension,
+            ..ExplicitConfigOverrides::default()
+        };

-            // Unsupported on the formatter CLI, but required on `Overrides`.
+        let config_args = ConfigArguments::from_cli_arguments(global_options, cli_overrides)?;
+        Ok((format_arguments, config_args))
+    }
+}
+
+impl AnalyzeGraphCommand {
+    /// Partition the CLI into command-line arguments and configuration
+    /// overrides.
+    pub fn partition(
+        self,
+        global_options: GlobalConfigArgs,
+    ) -> anyhow::Result<(AnalyzeGraphArgs, ConfigArguments)> {
+        let format_arguments = AnalyzeGraphArgs {
+            files: self.files,
+            direction: self.direction,
+        };
+
+        let cli_overrides = ExplicitConfigOverrides {
+            detect_string_imports: if self.detect_string_imports {
+                Some(true)
+            } else {
+                None
+            },
+            preview: resolve_bool_arg(self.preview, self.no_preview).map(PreviewMode::from),
+            target_version: self.target_version,
            ..ExplicitConfigOverrides::default()
        };

@@ -896,7 +955,7 @@ A `--config` flag must either be a path to a `.toml` configuration file
        // the user was trying to pass in a path to a configuration file
        // or some inline TOML.
        // We want to display the most helpful error to the user as possible.
-        if std::path::Path::new(value)
+        if Path::new(value)
            .extension()
            .map_or(false, |ext| ext.eq_ignore_ascii_case("toml"))
        {
@@ -1156,6 +1215,13 @@ impl LineColumnParseError {
    }
 }

+/// CLI settings that are distinct from configuration (commands, lists of files, etc.).
+#[derive(Clone, Debug)]
+pub struct AnalyzeGraphArgs {
+    pub files: Vec<PathBuf>,
+    pub direction: Direction,
+}
+
 /// Configuration overrides provided via dedicated CLI flags:
 /// `--line-length`, `--respect-gitignore`, etc.
 #[derive(Clone, Default)]
@@ -1187,6 +1253,7 @@ struct ExplicitConfigOverrides {
    output_format: Option<OutputFormat>,
    show_fixes: Option<bool>,
    extension: Option<Vec<ExtensionPair>>,
+    detect_string_imports: Option<bool>,
 }

 impl ConfigurationTransformer for ExplicitConfigOverrides {
@@ -1271,6 +1338,9 @@ impl ConfigurationTransformer for ExplicitConfigOverrides {
        if let Some(extension) = &self.extension {
            config.extension = Some(extension.iter().cloned().collect());
        }
+        if let Some(detect_string_imports) = &self.detect_string_imports {
+            config.analyze.detect_string_imports = Some(*detect_string_imports);
+        }

        config
    }
--- a/crates/ruff/src/commands/add_noqa.rs
+++ b/crates/ruff/src/commands/add_noqa.rs
@@ -10,7 +10,9 @@ use ruff_linter::linter::add_noqa_to_path;
 use ruff_linter::source_kind::SourceKind;
 use ruff_linter::warn_user_once;
 use ruff_python_ast::{PySourceType, SourceType};
-use ruff_workspace::resolver::{python_files_in_path, PyprojectConfig, ResolvedFile};
+use ruff_workspace::resolver::{
+    match_exclusion, python_files_in_path, PyprojectConfig, ResolvedFile,
+};

 use crate::args::ConfigArguments;

@@ -57,6 +59,15 @@ pub(crate) fn add_noqa(
                .and_then(|parent| package_roots.get(parent))
                .and_then(|package| *package);
            let settings = resolver.resolve(path);
+            if (settings.file_resolver.force_exclude || !resolved_file.is_root())
+                && match_exclusion(
+                    resolved_file.path(),
+                    resolved_file.file_name(),
+                    &settings.linter.exclude,
+                )
+            {
+                return None;
+            }
            let source_kind = match SourceKind::from_path(path, source_type) {
                Ok(Some(source_kind)) => source_kind,
                Ok(None) => return None,
--- a/crates/ruff/src/commands/analyze_graph.rs
+++ b/crates/ruff/src/commands/analyze_graph.rs
@@ -0,0 +1,241 @@
+use crate::args::{AnalyzeGraphArgs, ConfigArguments};
+use crate::resolve::resolve;
+use crate::{resolve_default_files, ExitStatus};
+use anyhow::Result;
+use log::{debug, warn};
+use path_absolutize::CWD;
+use ruff_db::system::{SystemPath, SystemPathBuf};
+use ruff_graph::{Direction, ImportMap, ModuleDb, ModuleImports};
+use ruff_linter::{warn_user, warn_user_once};
+use ruff_python_ast::{PySourceType, SourceType};
+use ruff_workspace::resolver::{match_exclusion, python_files_in_path, ResolvedFile};
+use rustc_hash::FxHashMap;
+use std::path::{Path, PathBuf};
+use std::sync::{Arc, Mutex};
+
+/// Generate an import map.
+pub(crate) fn analyze_graph(
+    args: AnalyzeGraphArgs,
+    config_arguments: &ConfigArguments,
+) -> Result<ExitStatus> {
+    // Construct the "default" settings. These are used when no `pyproject.toml`
+    // files are present, or files are injected from outside the hierarchy.
+    let pyproject_config = resolve(config_arguments, None)?;
+    if pyproject_config.settings.analyze.preview.is_disabled() {
+        warn_user!("`ruff analyze graph` is experimental and may change without warning");
+    }
+
+    // Write all paths relative to the current working directory.
+    let root =
+        SystemPathBuf::from_path_buf(CWD.clone()).expect("Expected a UTF-8 working directory");
+
+    // Find all Python files.
+    let files = resolve_default_files(args.files, false);
+    let (paths, resolver) = python_files_in_path(&files, &pyproject_config, config_arguments)?;
+
+    if paths.is_empty() {
+        warn_user_once!("No Python files found under the given path(s)");
+        return Ok(ExitStatus::Success);
+    }
+
+    // Resolve all package roots.
+    let package_roots = resolver
+        .package_roots(
+            &paths
+                .iter()
+                .flatten()
+                .map(ResolvedFile::path)
+                .collect::<Vec<_>>(),
+        )
+        .into_iter()
+        .map(|(path, package)| (path.to_path_buf(), package.map(Path::to_path_buf)))
+        .collect::<FxHashMap<_, _>>();
+
+    // Create a database from the source roots.
+    let db = ModuleDb::from_src_roots(
+        package_roots
+            .values()
+            .filter_map(|package| package.as_deref())
+            .filter_map(|package| package.parent())
+            .map(Path::to_path_buf)
+            .filter_map(|path| SystemPathBuf::from_path_buf(path).ok()),
+        pyproject_config
+            .settings
+            .analyze
+            .target_version
+            .as_tuple()
+            .into(),
+    )?;
+
+    // Create a cache for resolved globs.
+    let glob_resolver = Arc::new(Mutex::new(GlobResolver::default()));
+
+    // Collect and resolve the imports for each file.
+    let result = Arc::new(Mutex::new(Vec::new()));
+    let inner_result = Arc::clone(&result);
+
+    rayon::scope(move |scope| {
+        for resolved_file in paths {
+            let Ok(resolved_file) = resolved_file else {
+                continue;
+            };
+
+            let path = resolved_file.path();
+            let package = path
+                .parent()
+                .and_then(|parent| package_roots.get(parent))
+                .and_then(Clone::clone);
+
+            // Resolve the per-file settings.
+            let settings = resolver.resolve(path);
+            let string_imports = settings.analyze.detect_string_imports;
+            let include_dependencies = settings.analyze.include_dependencies.get(path).cloned();
+
+            // Skip excluded files.
+            if (settings.file_resolver.force_exclude || !resolved_file.is_root())
+                && match_exclusion(
+                    resolved_file.path(),
+                    resolved_file.file_name(),
+                    &settings.analyze.exclude,
+                )
+            {
+                continue;
+            }
+
+            // Ignore non-Python files.
+            let source_type = match settings.analyze.extension.get(path) {
+                None => match SourceType::from(&path) {
+                    SourceType::Python(source_type) => source_type,
+                    SourceType::Toml(_) => {
+                        debug!("Ignoring TOML file: {}", path.display());
+                        continue;
+                    }
+                },
+                Some(language) => PySourceType::from(language),
+            };
+            if matches!(source_type, PySourceType::Ipynb) {
+                debug!("Ignoring Jupyter notebook: {}", path.display());
+                continue;
+            }
+
+            // Convert to system paths.
+            let Ok(package) = package.map(SystemPathBuf::from_path_buf).transpose() else {
+                warn!("Failed to convert package to system path");
+                continue;
+            };
+            let Ok(path) = SystemPathBuf::from_path_buf(resolved_file.into_path()) else {
+                warn!("Failed to convert path to system path");
+                continue;
+            };
+
+            let db = db.snapshot();
+            let glob_resolver = glob_resolver.clone();
+            let root = root.clone();
+            let result = inner_result.clone();
+            scope.spawn(move |_| {
+                // Identify any imports via static analysis.
+                let mut imports =
+                    ModuleImports::detect(&db, &path, package.as_deref(), string_imports)
+                        .unwrap_or_else(|err| {
+                            warn!("Failed to generate import map for {path}: {err}");
+                            ModuleImports::default()
+                        });
+
+                debug!("Discovered {} imports for {}", imports.len(), path);
+
+                // Append any imports that were statically defined in the configuration.
+                if let Some((root, globs)) = include_dependencies {
+                    let mut glob_resolver = glob_resolver.lock().unwrap();
+                    imports.extend(glob_resolver.resolve(root, globs));
+                }
+
+                // Convert the path (and imports) to be relative to the working directory.
+                let path = path
+                    .strip_prefix(&root)
+                    .map(SystemPath::to_path_buf)
+                    .unwrap_or(path);
+                let imports = imports.relative_to(&root);
+
+                result.lock().unwrap().push((path, imports));
+            });
+        }
+    });
+
+    // Collect the results.
+    let imports = Arc::into_inner(result).unwrap().into_inner()?;
+
+    // Generate the import map.
+    let import_map = match args.direction {
+        Direction::Dependencies => ImportMap::from_iter(imports),
+        Direction::Dependents => ImportMap::reverse(imports),
+    };
+
+    // Print to JSON.
+    println!("{}", serde_json::to_string_pretty(&import_map)?);
+
+    Ok(ExitStatus::Success)
+}
+
+/// A resolver for glob sets.
+#[derive(Default, Debug)]
+struct GlobResolver {
+    cache: GlobCache,
+}
+
+impl GlobResolver {
+    /// Resolve a set of globs, anchored at a given root.
+    fn resolve(&mut self, root: PathBuf, globs: Vec<String>) -> Vec<SystemPathBuf> {
+        if let Some(cached) = self.cache.get(&root, &globs) {
+            return cached.clone();
+        }
+
+        let walker = match globwalk::GlobWalkerBuilder::from_patterns(&root, &globs)
+            .file_type(globwalk::FileType::FILE)
+            .build()
+        {
+            Ok(walker) => walker,
+            Err(err) => {
+                warn!("Failed to read glob walker: {err}");
+                return Vec::new();
+            }
+        };
+
+        let mut paths = Vec::new();
+        for entry in walker {
+            let entry = match entry {
+                Ok(entry) => entry,
+                Err(err) => {
+                    warn!("Failed to read glob entry: {err}");
+                    continue;
+                }
+            };
+            let path = match SystemPathBuf::from_path_buf(entry.into_path()) {
+                Ok(path) => path,
+                Err(err) => {
+                    warn!("Failed to convert path to system path: {}", err.display());
+                    continue;
+                }
+            };
+            paths.push(path);
+        }
+
+        self.cache.insert(root, globs, paths.clone());
+        paths
+    }
+}
+
+/// A cache for resolved globs.
+#[derive(Default, Debug)]
+struct GlobCache(FxHashMap<PathBuf, FxHashMap<Vec<String>, Vec<SystemPathBuf>>>);
+
+impl GlobCache {
+    /// Insert a resolved glob.
+    fn insert(&mut self, root: PathBuf, globs: Vec<String>, paths: Vec<SystemPathBuf>) {
+        self.0.entry(root).or_default().insert(globs, paths);
+    }
+
+    /// Get a resolved glob.
+    fn get(&self, root: &Path, globs: &[String]) -> Option<&Vec<SystemPathBuf>> {
+        self.0.get(root).and_then(|map| map.get(globs))
+    }
+}
--- a/crates/ruff/src/commands/format.rs
+++ b/crates/ruff/src/commands/format.rs
@@ -810,7 +810,11 @@ pub(super) fn warn_incompatible_formatter_settings(resolver: &Resolver) {
            .map(|rule| format!("`{}`", rule.noqa_code()))
            .collect();
        rule_names.sort();
-        warn_user_once!("The following rules may cause conflicts when used with the formatter: {}. To avoid unexpected behavior, we recommend disabling these rules, either by removing them from the `select` or `extend-select` configuration, or adding them to the `ignore` configuration.", rule_names.join(", "));
+        if let [rule] = rule_names.as_slice() {
+            warn_user_once!("The following rule may cause conflicts when used with the formatter: {rule}. To avoid unexpected behavior, we recommend disabling this rule, either by removing it from the `select` or `extend-select` configuration, or adding it to the `ignore` configuration.");
+        } else {
+            warn_user_once!("The following rules may cause conflicts when used with the formatter: {}. To avoid unexpected behavior, we recommend disabling these rules, either by removing them from the `select` or `extend-select` configuration, or adding them to the `ignore` configuration.", rule_names.join(", "));
+        }
    }

    // Next, validate settings-specific incompatibilities.
--- a/crates/ruff/src/commands/mod.rs
+++ b/crates/ruff/src/commands/mod.rs
@@ -1,4 +1,5 @@
 pub(crate) mod add_noqa;
+pub(crate) mod analyze_graph;
 pub(crate) mod check;
 pub(crate) mod check_stdin;
 pub(crate) mod clean;
--- a/crates/ruff/src/lib.rs
+++ b/crates/ruff/src/lib.rs
@@ -20,7 +20,9 @@ use ruff_linter::settings::types::OutputFormat;
 use ruff_linter::{fs, warn_user, warn_user_once};
 use ruff_workspace::Settings;

-use crate::args::{Args, CheckCommand, Command, FormatCommand};
+use crate::args::{
+    AnalyzeCommand, AnalyzeGraphCommand, Args, CheckCommand, Command, FormatCommand,
+};
 use crate::printer::{Flags as PrinterFlags, Printer};

 pub mod args;
@@ -186,6 +188,7 @@ pub fn run(
        Command::Check(args) => check(args, global_options),
        Command::Format(args) => format(args, global_options),
        Command::Server(args) => server(args),
+        Command::Analyze(AnalyzeCommand::Graph(args)) => analyze_graph(args, global_options),
    }
 }

@@ -199,6 +202,15 @@ fn format(args: FormatCommand, global_options: GlobalConfigArgs) -> Result<ExitS
    }
 }

+fn analyze_graph(
+    args: AnalyzeGraphCommand,
+    global_options: GlobalConfigArgs,
+) -> Result<ExitStatus> {
+    let (cli, config_arguments) = args.partition(global_options)?;
+
+    commands::analyze_graph::analyze_graph(cli, &config_arguments)
+}
+
 fn server(args: ServerCommand) -> Result<ExitStatus> {
    let four = NonZeroUsize::new(4).unwrap();

--- a/Show More
+++ b/Show More