Separate TOC from the navigation

2024-09-05 16:08:53 +05:30
109 changed files with 1040 additions and 4889 deletions
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -45,7 +45,7 @@ repos:
          )$

  - repo: https://github.com/crate-ci/typos
-    rev: v1.24.5
+    rev: v1.24.3
    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: v0.6.4
+    rev: v0.6.3
    hooks:
      - id: ruff-format
      - id: ruff
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,64 +1,5 @@
 # Changelog

-## 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
@@ -194,15 +194,6 @@ 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"
@@ -520,15 +511,6 @@ 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"
@@ -634,16 +616,6 @@ 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"
@@ -722,16 +694,6 @@ version = "0.1.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "56254986775e3233ffa9c4d7d3faaf6d36a2c09d30b20687e9f88bc8bafc16c8"

-[[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"
@@ -917,16 +879,6 @@ 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"
@@ -1160,8 +1112,6 @@ dependencies = [
 "globset",
 "lazy_static",
 "linked-hash-map",
- "pest",
- "pest_derive",
 "regex",
 "serde",
 "similar",
@@ -1757,51 +1707,6 @@ 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"
@@ -2031,7 +1936,6 @@ dependencies = [
 "smallvec",
 "static_assertions",
 "tempfile",
- "test-case",
 "thiserror",
 "tracing",
 "walkdir",
@@ -2187,7 +2091,7 @@ dependencies = [

 [[package]]
 name = "ruff"
-version = "0.6.5"
+version = "0.6.3"
 dependencies = [
 "anyhow",
 "argfile",
@@ -2380,7 +2284,7 @@ dependencies = [

 [[package]]
 name = "ruff_linter"
-version = "0.6.5"
+version = "0.6.3"
 dependencies = [
 "aho-corasick",
 "annotate-snippets 0.9.2",
@@ -2700,7 +2604,7 @@ dependencies = [

 [[package]]
 name = "ruff_wasm"
-version = "0.6.5"
+version = "0.6.3"
 dependencies = [
 "console_error_panic_hook",
 "console_log",
@@ -3031,17 +2935,6 @@ 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"
@@ -3442,18 +3335,6 @@ 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/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/0.6.5/install.sh | sh
-powershell -c "irm https://astral.sh/ruff/0.6.5/install.ps1 | iex"
+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"
 ```

 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: v0.6.5
+  rev: v0.6.3
  hooks:
    # Run the linter.
    - id: ruff
--- a/crates/red_knot_python_semantic/Cargo.toml
+++ b/crates/red_knot_python_semantic/Cargo.toml
@@ -33,7 +33,6 @@ rustc-hash = { workspace = true }
 hashbrown = { workspace = true }
 smallvec = { workspace = true }
 static_assertions = { workspace = true }
-test-case = { workspace = true }

 [build-dependencies]
 path-slash = { workspace = true }
--- a/crates/red_knot_python_semantic/src/builtins.rs
+++ b/crates/red_knot_python_semantic/src/builtins.rs
@@ -0,0 +1,16 @@
+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
@@ -10,6 +10,7 @@ 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;
@@ -19,7 +20,6 @@ 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/path.rs
+++ b/crates/red_knot_python_semantic/src/module_resolver/path.rs
@@ -59,10 +59,6 @@ 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
@@ -569,16 +569,24 @@ fn resolve_name(db: &dyn Db, name: &ModuleName) -> Option<(SearchPath, File, Mod

                package_path.push(module_name);

-                // 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));
+                // 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 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));
+                if let Some(module) = package_path
+                    .with_py_extension()
+                    .and_then(|path| path.to_file(&resolver_state))
+                {
+                    return Some((search_path.clone(), module, kind));
                }

                // For regular packages, don't search the next search path. All files of that
@@ -599,23 +607,6 @@ 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,
@@ -642,10 +633,7 @@ where

        if is_regular_package {
            in_namespace_package = false;
-        } 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()
-        {
+        } else if package_path.is_directory(resolver_state) {
            // A directory without an `__init__.py` is a namespace package, continue with the next folder.
            in_namespace_package = true;
        } else if in_namespace_package {
@@ -1103,25 +1091,6 @@ 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/semantic_index.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index.rs
@@ -21,7 +21,6 @@ use crate::Db;

 pub mod ast_ids;
 mod builder;
-pub(crate) mod constraint;
 pub mod definition;
 pub mod expression;
 pub mod symbol;
--- a/crates/red_knot_python_semantic/src/semantic_index/builder.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/builder.rs
@@ -26,10 +26,7 @@ use crate::semantic_index::use_def::{FlowSnapshot, UseDefMapBuilder};
 use crate::semantic_index::SemanticIndex;
 use crate::Db;

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

 pub(super) struct SemanticIndexBuilder<'db> {
    // Builder state
@@ -196,50 +193,21 @@ impl<'db> SemanticIndexBuilder<'db> {
            countme::Count::default(),
        );

-        let existing_definition = self
-            .definitions_by_node
+        self.definitions_by_node
            .insert(definition_node.key(), definition);
-        debug_assert_eq!(existing_definition, None);
-
        self.current_use_def_map_mut()
            .record_definition(symbol, definition);

        definition
    }

-    fn add_expression_constraint(&mut self, constraint_node: &ast::Expr) -> Expression<'db> {
+    fn add_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(Constraint::Expression(expression));
+        self.current_use_def_map_mut().record_constraint(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> {
@@ -359,11 +327,10 @@ 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)
-            let existing_definition = self.definitions_by_node.insert(
+            self.definitions_by_node.insert(
                DefinitionNodeRef::from(AnyParameterRef::Variadic(&with_default.parameter)).key(),
                definition,
            );
-            debug_assert_eq!(existing_definition, None);
        }
    }

@@ -527,6 +494,7 @@ 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);
@@ -552,7 +520,7 @@ where
            ast::Stmt::If(node) => {
                self.visit_expr(&node.test);
                let pre_if = self.flow_snapshot();
-                self.add_expression_constraint(&node.test);
+                self.add_constraint(&node.test);
                self.visit_body(&node.body);
                let mut post_clauses: Vec<FlowSnapshot> = vec![];
                for clause in &node.elif_else_clauses {
@@ -577,23 +545,14 @@ where
                    self.flow_merge(pre_if);
                }
            }
-            ast::Stmt::While(ast::StmtWhile {
-                test,
-                body,
-                orelse,
-                range: _,
-            }) => {
-                self.visit_expr(test);
+            ast::Stmt::While(node) => {
+                self.visit_expr(&node.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);
-
-                // TODO: definitions created inside the body should be fully visible
-                // to other statements/expressions inside the body --Alex/Carl
-                self.visit_body(body);
-
+                self.visit_body(&node.body);
                // Get the break states from the body of this loop, and restore the saved outer
                // ones.
                let break_states =
@@ -602,7 +561,7 @@ 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(orelse);
+                self.visit_body(&node.orelse);

                // Breaking out of a while loop bypasses the `else` clause, so merge in the break
                // states after visiting `else`.
@@ -636,35 +595,15 @@ 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,
@@ -673,75 +612,9 @@ where
            }) => {
                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);
+                for case in cases {
                    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_or_update_symbol(symbol_name.id.clone(), SymbolFlags::IS_DEFINED);
-
-                        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);
@@ -756,22 +629,21 @@ where

        match expr {
            ast::Expr::Name(name_node @ ast::ExprName { id, ctx, .. }) => {
-                let flags = match (ctx, self.current_assignment) {
-                    (ast::ExprContext::Store, Some(CurrentAssignment::AugAssign(_))) => {
-                        // For augmented assignment, the target expression is also used.
-                        SymbolFlags::IS_DEFINED | SymbolFlags::IS_USED
-                    }
-                    (ast::ExprContext::Store, Some(CurrentAssignment::AnnAssign(ann_assign)))
-                        if ann_assign.value.is_none() =>
-                    {
-                        // An annotated assignment that doesn't assign a value is not a Definition
-                        SymbolFlags::empty()
-                    }
-                    (ast::ExprContext::Load, _) => SymbolFlags::IS_USED,
-                    (ast::ExprContext::Store, _) => SymbolFlags::IS_DEFINED,
-                    (ast::ExprContext::Del, _) => SymbolFlags::IS_DEFINED,
-                    (ast::ExprContext::Invalid, _) => SymbolFlags::empty(),
+                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(),
                };
+                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) {
                    match self.current_assignment {
@@ -796,7 +668,6 @@ where
                                ForStmtDefinitionNodeRef {
                                    iterable: &node.iter,
                                    target: name_node,
-                                    is_async: node.is_async,
                                },
                            );
                        }
@@ -813,7 +684,6 @@ where
                                    iterable: &node.iter,
                                    target: name_node,
                                    first,
-                                    is_async: node.is_async,
                                },
                            );
                        }
--- a/crates/red_knot_python_semantic/src/semantic_index/constraint.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/constraint.rs
@@ -1,39 +0,0 @@
-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
@@ -50,7 +50,6 @@ pub(crate) enum DefinitionNodeRef<'a> {
    Parameter(ast::AnyParameterRef<'a>),
    WithItem(WithItemDefinitionNodeRef<'a>),
    MatchPattern(MatchPatternDefinitionNodeRef<'a>),
-    ExceptHandler(ExceptHandlerDefinitionNodeRef<'a>),
 }

 impl<'a> From<&'a ast::StmtFunctionDef> for DefinitionNodeRef<'a> {
@@ -153,13 +152,6 @@ 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)]
@@ -167,7 +159,6 @@ pub(crate) struct ComprehensionDefinitionNodeRef<'a> {
    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)]
@@ -215,25 +206,20 @@ impl DefinitionNodeRef<'_> {
            DefinitionNodeRef::AugmentedAssignment(augmented_assignment) => {
                DefinitionKind::AugmentedAssignment(AstNodeRef::new(parsed, augmented_assignment))
            }
-            DefinitionNodeRef::For(ForStmtDefinitionNodeRef {
-                iterable,
-                target,
-                is_async,
-            }) => DefinitionKind::For(ForStmtDefinitionKind {
-                iterable: AstNodeRef::new(parsed.clone(), iterable),
-                target: AstNodeRef::new(parsed, target),
-                is_async,
-            }),
+            DefinitionNodeRef::For(ForStmtDefinitionNodeRef { iterable, target }) => {
+                DefinitionKind::For(ForStmtDefinitionKind {
+                    iterable: AstNodeRef::new(parsed.clone(), iterable),
+                    target: AstNodeRef::new(parsed, target),
+                })
+            }
            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) => {
@@ -258,13 +244,6 @@ impl DefinitionNodeRef<'_> {
                identifier: AstNodeRef::new(parsed, identifier),
                index,
            }),
-            DefinitionNodeRef::ExceptHandler(ExceptHandlerDefinitionNodeRef {
-                handler,
-                is_star,
-            }) => DefinitionKind::ExceptHandler(ExceptHandlerDefinitionKind {
-                handler: AstNodeRef::new(parsed.clone(), handler),
-                is_star,
-            }),
        }
    }

@@ -286,7 +265,6 @@ impl DefinitionNodeRef<'_> {
            Self::For(ForStmtDefinitionNodeRef {
                iterable: _,
                target,
-                is_async: _,
            }) => target.into(),
            Self::Comprehension(ComprehensionDefinitionNodeRef { target, .. }) => target.into(),
            Self::Parameter(node) => match node {
@@ -297,7 +275,6 @@ impl DefinitionNodeRef<'_> {
            Self::MatchPattern(MatchPatternDefinitionNodeRef { identifier, .. }) => {
                identifier.into()
            }
-            Self::ExceptHandler(ExceptHandlerDefinitionNodeRef { handler, .. }) => handler.into(),
        }
    }
 }
@@ -318,7 +295,6 @@ pub enum DefinitionKind {
    ParameterWithDefault(AstNodeRef<ast::ParameterWithDefault>),
    WithItem(WithItemDefinitionKind),
    MatchPattern(MatchPatternDefinitionKind),
-    ExceptHandler(ExceptHandlerDefinitionKind),
 }

 #[derive(Clone, Debug)]
@@ -344,7 +320,6 @@ pub struct ComprehensionDefinitionKind {
    iterable: AstNodeRef<ast::Expr>,
    target: AstNodeRef<ast::ExprName>,
    first: bool,
-    is_async: bool,
 }

 impl ComprehensionDefinitionKind {
@@ -359,10 +334,6 @@ impl ComprehensionDefinitionKind {
    pub(crate) fn is_first(&self) -> bool {
        self.first
    }
-
-    pub(crate) fn is_async(&self) -> bool {
-        self.is_async
-    }
 }

 #[derive(Clone, Debug)]
@@ -417,7 +388,6 @@ impl WithItemDefinitionKind {
 pub struct ForStmtDefinitionKind {
    iterable: AstNodeRef<ast::Expr>,
    target: AstNodeRef<ast::ExprName>,
-    is_async: bool,
 }

 impl ForStmtDefinitionKind {
@@ -428,26 +398,6 @@ 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 handled_exceptions(&self) -> Option<&ast::Expr> {
-        self.handler.node().type_.as_deref()
-    }
-
-    pub(crate) fn is_star(&self) -> bool {
-        self.is_star
-    }
 }

 #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
@@ -518,9 +468,3 @@ impl From<&ast::Identifier> for DefinitionNodeKey {
        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/use_def.rs
+++ b/crates/red_knot_python_semantic/src/semantic_index/use_def.rs
@@ -146,11 +146,10 @@ use self::symbol_state::{
 };
 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 super::constraint::Constraint;
-
 mod bitset;
 mod symbol_state;

@@ -160,8 +159,8 @@ pub(crate) struct UseDefMap<'db> {
    /// Array of [`Definition`] in this scope.
    all_definitions: IndexVec<ScopedDefinitionId, Definition<'db>>,

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

    /// [`SymbolState`] visible at a [`ScopedUseId`].
    definitions_by_use: IndexVec<ScopedUseId, SymbolState>,
@@ -205,7 +204,7 @@ impl<'db> UseDefMap<'db> {
 #[derive(Debug)]
 pub(crate) struct DefinitionWithConstraintsIterator<'map, 'db> {
    all_definitions: &'map IndexVec<ScopedDefinitionId, Definition<'db>>,
-    all_constraints: &'map IndexVec<ScopedConstraintId, Constraint<'db>>,
+    all_constraints: &'map IndexVec<ScopedConstraintId, Expression<'db>>,
    inner: DefinitionIdWithConstraintsIterator<'map>,
 }

@@ -233,12 +232,12 @@ pub(crate) struct DefinitionWithConstraints<'map, 'db> {
 }

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

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

    fn next(&mut self) -> Option<Self::Item> {
        self.constraint_ids
@@ -260,8 +259,8 @@ pub(super) struct UseDefMapBuilder<'db> {
    /// Append-only array of [`Definition`]; None is unbound.
    all_definitions: IndexVec<ScopedDefinitionId, Definition<'db>>,

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

    /// Visible definitions at each so-far-recorded use.
    definitions_by_use: IndexVec<ScopedUseId, SymbolState>,
@@ -291,7 +290,7 @@ impl<'db> UseDefMapBuilder<'db> {
        self.definitions_by_symbol[symbol] = SymbolState::with(def_id);
    }

-    pub(super) fn record_constraint(&mut self, constraint: Constraint<'db>) {
+    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);
--- 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
@@ -32,26 +32,17 @@ impl<const B: usize> BitSet<B> {
        bitset
    }

-    #[allow(unused)]
-    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, 0);
+                vec.resize(num_blocks_needed as usize, 0);
                *self = Self::Heap(vec);
            }
            Self::Heap(vec) => {
-                vec.resize(num_blocks_needed, 0);
+                vec.resize(num_blocks_needed as usize, 0);
            }
        }
    }
@@ -98,20 +89,6 @@ impl<const B: usize> BitSet<B> {
        }
    }

-    /// Union in-place with another [`BitSet`].
-    #[allow(unused)]
-    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();
@@ -241,59 +218,6 @@ 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);
@@ -301,11 +225,4 @@ 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_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, infer_scope_types, Type};
+use crate::types::{definition_ty, global_symbol_ty_by_name, 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(self.db, module.file(), symbol_name)
+        global_symbol_ty_by_name(self.db, module.file(), symbol_name)
    }
 }

--- a/crates/red_knot_python_semantic/src/stdlib.rs
+++ b/crates/red_knot_python_semantic/src/stdlib.rs
@@ -1,77 +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::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,
-}
-
-impl CoreStdlibModule {
-    fn name(self) -> ModuleName {
-        let module_name = match self {
-            Self::Builtins => "builtins",
-            Self::Types => "types",
-            Self::Typeshed => "_typeshed",
-        };
-        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)
-}
-
-/// 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
@@ -1,8 +1,7 @@
-use infer::TypeInferenceBuilder;
 use ruff_db::files::File;
 use ruff_python_ast as ast;

-use crate::module_resolver::file_to_module;
+use crate::builtins::builtins_scope;
 use crate::semantic_index::ast_ids::HasScopedAstId;
 use crate::semantic_index::definition::{Definition, DefinitionKind};
 use crate::semantic_index::symbol::{ScopeId, ScopedSymbolId};
@@ -10,7 +9,6 @@ use crate::semantic_index::{
    global_scope, semantic_index, symbol_table, use_def_map, DefinitionWithConstraints,
    DefinitionWithConstraintsIterator,
 };
-use crate::stdlib::{builtins_symbol_ty, types_symbol_ty, typeshed_symbol_ty};
 use crate::types::narrow::narrowing_constraint;
 use crate::{Db, FxOrderSet};

@@ -18,6 +16,7 @@ pub(crate) use self::builder::{IntersectionBuilder, UnionBuilder};
 pub(crate) use self::diagnostic::TypeCheckDiagnostics;
 pub(crate) use self::infer::{
    infer_deferred_types, infer_definition_types, infer_expression_types, infer_scope_types,
+    TypeInference,
 };

 mod builder;
@@ -41,7 +40,7 @@ pub fn check_types(db: &dyn Db, file: File) -> TypeCheckDiagnostics {
 }

 /// Infer the public type of a symbol (its type as seen from outside its scope).
-pub(crate) fn symbol_ty_by_id<'db>(
+pub(crate) fn symbol_ty<'db>(
    db: &'db dyn Db,
    scope: ScopeId<'db>,
    symbol: ScopedSymbolId,
@@ -59,17 +58,30 @@ pub(crate) fn symbol_ty_by_id<'db>(
 }

 /// Shorthand for `symbol_ty` that takes a symbol name instead of an ID.
-pub(crate) fn symbol_ty<'db>(db: &'db dyn Db, scope: ScopeId<'db>, name: &str) -> Type<'db> {
+pub(crate) fn symbol_ty_by_name<'db>(
+    db: &'db dyn Db,
+    scope: ScopeId<'db>,
+    name: &str,
+) -> Type<'db> {
    let table = symbol_table(db, scope);
    table
        .symbol_id_by_name(name)
-        .map(|symbol| symbol_ty_by_id(db, scope, symbol))
+        .map(|symbol| symbol_ty(db, scope, symbol))
        .unwrap_or(Type::Unbound)
 }

 /// Shorthand for `symbol_ty` that looks up a module-global symbol by name in a file.
-pub(crate) fn global_symbol_ty<'db>(db: &'db dyn Db, file: File, name: &str) -> Type<'db> {
-    symbol_ty(db, global_scope(db, file), name)
+pub(crate) fn global_symbol_ty_by_name<'db>(db: &'db dyn Db, file: File, name: &str) -> Type<'db> {
+    symbol_ty_by_name(db, global_scope(db, file), name)
+}
+
+/// Shorthand for `symbol_ty` that looks up a symbol in the builtins.
+///
+/// Returns `Unbound` if the builtins module isn't available for some reason.
+pub(crate) fn builtins_symbol_ty_by_name<'db>(db: &'db dyn Db, name: &str) -> Type<'db> {
+    builtins_scope(db)
+        .map(|builtins| symbol_ty_by_name(db, builtins, name))
+        .unwrap_or(Type::Unbound)
 }

 /// Infer the type of a [`Definition`].
@@ -121,8 +133,8 @@ pub(crate) fn definitions_ty<'db>(
             definition,
             constraints,
         }| {
-            let mut constraint_tys = constraints
-                .filter_map(|constraint| narrowing_constraint(db, constraint, definition));
+            let mut constraint_tys =
+                constraints.filter_map(|test| narrowing_constraint(db, test, definition));
            let definition_ty = definition_ty(db, definition);
            if let Some(first_constraint_ty) = constraint_tys.next() {
                let mut builder = IntersectionBuilder::new(db);
@@ -145,7 +157,14 @@ pub(crate) fn definitions_ty<'db>(
        .expect("definitions_ty should never be called with zero definitions and no unbound_ty.");

    if let Some(second) = all_types.next() {
-        UnionType::from_elements(db, [first, second].into_iter().chain(all_types))
+        let mut builder = UnionBuilder::new(db);
+        builder = builder.add(first).add(second);
+
+        for variant in all_types {
+            builder = builder.add(variant);
+        }
+
+        builder.build()
    } else {
        first
    }
@@ -189,9 +208,6 @@ pub enum Type<'db> {
    LiteralString,
    /// A bytes literal
    BytesLiteral(BytesLiteralType<'db>),
-    /// A heterogeneous tuple type, with elements of the given types in source order.
-    // TODO: Support variable length homogeneous tuple type like `tuple[int, ...]`.
-    Tuple(TupleType<'db>),
    // TODO protocols, callable types, overloads, generics, type vars
 }

@@ -290,53 +306,17 @@ impl<'db> Type<'db> {
    pub fn replace_unbound_with(&self, db: &'db dyn Db, replacement: Type<'db>) -> Type<'db> {
        match self {
            Type::Unbound => replacement,
-            Type::Union(union) => {
-                union.map(db, |element| element.replace_unbound_with(db, replacement))
-            }
+            Type::Union(union) => union
+                .elements(db)
+                .into_iter()
+                .fold(UnionBuilder::new(db), |builder, ty| {
+                    builder.add(ty.replace_unbound_with(db, replacement))
+                })
+                .build(),
            ty => *ty,
        }
    }

-    /// Return true if this type is [assignable to] type `target`.
-    ///
-    /// [assignable to]: https://typing.readthedocs.io/en/latest/spec/concepts.html#the-assignable-to-or-consistent-subtyping-relation
-    #[allow(unused)]
-    pub(crate) fn is_assignable_to(self, db: &'db dyn Db, target: Type<'db>) -> bool {
-        if self.is_equivalent_to(db, target) {
-            return true;
-        }
-        match (self, target) {
-            (Type::Unknown | Type::Any | Type::Never, _) => true,
-            (_, Type::Unknown | Type::Any) => true,
-            (Type::IntLiteral(_), Type::Instance(class))
-                if class.is_stdlib_symbol(db, "builtins", "int") =>
-            {
-                true
-            }
-            (Type::StringLiteral(_), Type::LiteralString) => true,
-            (Type::StringLiteral(_) | Type::LiteralString, Type::Instance(class))
-                if class.is_stdlib_symbol(db, "builtins", "str") =>
-            {
-                true
-            }
-            (Type::BytesLiteral(_), Type::Instance(class))
-                if class.is_stdlib_symbol(db, "builtins", "bytes") =>
-            {
-                true
-            }
-            // TODO
-            _ => false,
-        }
-    }
-
-    /// Return true if this type is equivalent to type `other`.
-    #[allow(unused)]
-    pub(crate) fn is_equivalent_to(self, _db: &'db dyn Db, other: Type<'db>) -> bool {
-        // TODO equivalent but not identical structural types, differently-ordered unions and
-        // intersections, other cases?
-        self == other
-    }
-
    /// Resolve a member access of a type.
    ///
    /// For example, if `foo` is `Type::Instance(<Bar>)`,
@@ -351,7 +331,7 @@ impl<'db> Type<'db> {
    /// us to explicitly consider whether to handle an error or propagate
    /// it up the call stack.
    #[must_use]
-    pub fn member(&self, db: &'db dyn Db, name: &str) -> Type<'db> {
+    pub fn member(&self, db: &'db dyn Db, name: &ast::name::Name) -> Type<'db> {
        match self {
            Type::Any => Type::Any,
            Type::Never => {
@@ -368,13 +348,19 @@ impl<'db> Type<'db> {
                // TODO: attribute lookup on function type
                Type::Unknown
            }
-            Type::Module(file) => global_symbol_ty(db, *file, name),
+            Type::Module(file) => global_symbol_ty_by_name(db, *file, name),
            Type::Class(class) => class.class_member(db, name),
            Type::Instance(_) => {
                // TODO MRO? get_own_instance_member, get_instance_member
                Type::Unknown
            }
-            Type::Union(union) => union.map(db, |element| element.member(db, name)),
+            Type::Union(union) => union
+                .elements(db)
+                .iter()
+                .fold(UnionBuilder::new(db), |builder, element_ty| {
+                    builder.add(element_ty.member(db, name))
+                })
+                .build(),
            Type::Intersection(_) => {
                // TODO perform the get_member on each type in the intersection
                // TODO return the intersection of those results
@@ -399,10 +385,6 @@ impl<'db> Type<'db> {
                // TODO defer to Type::Instance(<bytes from typeshed>).member
                Type::Unknown
            }
-            Type::Tuple(_) => {
-                // TODO: implement tuple methods
-                Type::Unknown
-            }
        }
    }

@@ -433,138 +415,13 @@ impl<'db> Type<'db> {
        }
    }

-    /// Given the type of an object that is iterated over in some way,
-    /// return the type of objects that are yielded by that iteration.
-    ///
-    /// E.g., for the following loop, given the type of `x`, infer the type of `y`:
-    /// ```python
-    /// for y in x:
-    ///     pass
-    /// ```
-    fn iterate(&self, db: &'db dyn Db) -> IterationOutcome<'db> {
-        if let Type::Tuple(tuple_type) = self {
-            return IterationOutcome::Iterable {
-                element_ty: UnionType::from_elements(db, &**tuple_type.elements(db)),
-            };
-        }
-
-        // `self` represents the type of the iterable;
-        // `__iter__` and `__next__` are both looked up on the class of the iterable:
-        let iterable_meta_type = self.to_meta_type(db);
-
-        let dunder_iter_method = iterable_meta_type.member(db, "__iter__");
-        if !dunder_iter_method.is_unbound() {
-            let Some(iterator_ty) = dunder_iter_method.call(db) else {
-                return IterationOutcome::NotIterable {
-                    not_iterable_ty: *self,
-                };
-            };
-
-            let dunder_next_method = iterator_ty.to_meta_type(db).member(db, "__next__");
-            return dunder_next_method
-                .call(db)
-                .map(|element_ty| IterationOutcome::Iterable { element_ty })
-                .unwrap_or(IterationOutcome::NotIterable {
-                    not_iterable_ty: *self,
-                });
-        }
-
-        // Although it's not considered great practice,
-        // classes that define `__getitem__` are also iterable,
-        // even if they do not define `__iter__`.
-        //
-        // TODO(Alex) this is only valid if the `__getitem__` method is annotated as
-        // accepting `int` or `SupportsIndex`
-        let dunder_get_item_method = iterable_meta_type.member(db, "__getitem__");
-
-        dunder_get_item_method
-            .call(db)
-            .map(|element_ty| IterationOutcome::Iterable { element_ty })
-            .unwrap_or(IterationOutcome::NotIterable {
-                not_iterable_ty: *self,
-            })
-    }
-
    #[must_use]
-    pub fn to_instance(&self, db: &'db dyn Db) -> Type<'db> {
+    pub fn to_instance(&self) -> Type<'db> {
        match self {
            Type::Any => Type::Any,
            Type::Unknown => Type::Unknown,
-            Type::Unbound => Type::Unknown,
-            Type::Never => Type::Never,
            Type::Class(class) => Type::Instance(*class),
-            Type::Union(union) => union.map(db, |element| element.to_instance(db)),
-            // TODO: we can probably do better here: --Alex
-            Type::Intersection(_) => Type::Unknown,
-            // TODO: calling `.to_instance()` on any of these should result in a diagnostic,
-            // since they already indicate that the object is an instance of some kind:
-            Type::BooleanLiteral(_)
-            | Type::BytesLiteral(_)
-            | Type::Function(_)
-            | Type::Instance(_)
-            | Type::Module(_)
-            | Type::IntLiteral(_)
-            | Type::StringLiteral(_)
-            | Type::Tuple(_)
-            | Type::LiteralString
-            | Type::None => Type::Unknown,
-        }
-    }
-
-    /// Given a type that is assumed to represent an instance of a class,
-    /// return a type that represents that class itself.
-    #[must_use]
-    pub fn to_meta_type(&self, db: &'db dyn Db) -> Type<'db> {
-        match self {
-            Type::Unbound => Type::Unbound,
-            Type::Never => Type::Never,
-            Type::Instance(class) => Type::Class(*class),
-            Type::Union(union) => union.map(db, |ty| ty.to_meta_type(db)),
-            Type::BooleanLiteral(_) => builtins_symbol_ty(db, "bool"),
-            Type::BytesLiteral(_) => builtins_symbol_ty(db, "bytes"),
-            Type::IntLiteral(_) => builtins_symbol_ty(db, "int"),
-            Type::Function(_) => types_symbol_ty(db, "FunctionType"),
-            Type::Module(_) => types_symbol_ty(db, "ModuleType"),
-            Type::None => typeshed_symbol_ty(db, "NoneType"),
-            // TODO not accurate if there's a custom metaclass...
-            Type::Class(_) => builtins_symbol_ty(db, "type"),
-            // TODO can we do better here? `type[LiteralString]`?
-            Type::StringLiteral(_) | Type::LiteralString => builtins_symbol_ty(db, "str"),
-            // TODO: `type[Any]`?
-            Type::Any => Type::Any,
-            // TODO: `type[Unknown]`?
-            Type::Unknown => Type::Unknown,
-            // TODO intersections
-            Type::Intersection(_) => Type::Unknown,
-            Type::Tuple(_) => builtins_symbol_ty(db, "tuple"),
-        }
-    }
-}
-
-impl<'db> From<&Type<'db>> for Type<'db> {
-    fn from(value: &Type<'db>) -> Self {
-        *value
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-enum IterationOutcome<'db> {
-    Iterable { element_ty: Type<'db> },
-    NotIterable { not_iterable_ty: Type<'db> },
-}
-
-impl<'db> IterationOutcome<'db> {
-    fn unwrap_with_diagnostic(
-        self,
-        iterable_node: ast::AnyNodeRef,
-        inference_builder: &mut TypeInferenceBuilder<'db>,
-    ) -> Type<'db> {
-        match self {
-            Self::Iterable { element_ty } => element_ty,
-            Self::NotIterable { not_iterable_ty } => {
-                inference_builder.not_iterable_diagnostic(iterable_node, not_iterable_ty);
-                Type::Unknown
-            }
+            _ => Type::Unknown, // TODO type errors
        }
    }
 }
@@ -629,15 +486,6 @@ pub struct ClassType<'db> {
 }

 impl<'db> ClassType<'db> {
-    /// Return true if this class is a standard library type with given module name and name.
-    #[allow(unused)]
-    pub(crate) fn is_stdlib_symbol(self, db: &'db dyn Db, module_name: &str, name: &str) -> bool {
-        name == self.name(db)
-            && file_to_module(db, self.body_scope(db).file(db)).is_some_and(|module| {
-                module.search_path().is_standard_library() && module.name() == module_name
-            })
-    }
-
    /// Return an iterator over the types of this class's bases.
    ///
    /// # Panics:
@@ -656,7 +504,7 @@ impl<'db> ClassType<'db> {
    /// Returns the class member of this class named `name`.
    ///
    /// The member resolves to a member of the class itself or any of its bases.
-    pub fn class_member(self, db: &'db dyn Db, name: &str) -> Type<'db> {
+    pub fn class_member(self, db: &'db dyn Db, name: &ast::name::Name) -> Type<'db> {
        let member = self.own_class_member(db, name);
        if !member.is_unbound() {
            return member;
@@ -666,12 +514,12 @@ impl<'db> ClassType<'db> {
    }

    /// Returns the inferred type of the class member named `name`.
-    pub fn own_class_member(self, db: &'db dyn Db, name: &str) -> Type<'db> {
+    pub fn own_class_member(self, db: &'db dyn Db, name: &ast::name::Name) -> Type<'db> {
        let scope = self.body_scope(db);
-        symbol_ty(db, scope, name)
+        symbol_ty_by_name(db, scope, name)
    }

-    pub fn inherited_class_member(self, db: &'db dyn Db, name: &str) -> Type<'db> {
+    pub fn inherited_class_member(self, db: &'db dyn Db, name: &ast::name::Name) -> Type<'db> {
        for base in self.bases(db) {
            let member = base.member(db, name);
            if !member.is_unbound() {
@@ -694,30 +542,6 @@ impl<'db> UnionType<'db> {
    pub fn contains(&self, db: &'db dyn Db, ty: Type<'db>) -> bool {
        self.elements(db).contains(&ty)
    }
-
-    /// Create a union from a list of elements
-    /// (which may be eagerly simplified into a different variant of [`Type`] altogether)
-    pub fn from_elements<T: Into<Type<'db>>>(
-        db: &'db dyn Db,
-        elements: impl IntoIterator<Item = T>,
-    ) -> Type<'db> {
-        elements
-            .into_iter()
-            .fold(UnionBuilder::new(db), |builder, element| {
-                builder.add(element.into())
-            })
-            .build()
-    }
-
-    /// Apply a transformation function to all elements of the union,
-    /// and create a new union from the resulting set of types
-    pub fn map(
-        &self,
-        db: &'db dyn Db,
-        transform_fn: impl Fn(&Type<'db>) -> Type<'db>,
-    ) -> Type<'db> {
-        Self::from_elements(db, self.elements(db).into_iter().map(transform_fn))
-    }
 }

 #[salsa::interned]
@@ -747,35 +571,29 @@ pub struct BytesLiteralType<'db> {
    value: Box<[u8]>,
 }

-#[salsa::interned]
-pub struct TupleType<'db> {
-    #[return_ref]
-    elements: Box<[Type<'db>]>,
-}
-
 #[cfg(test)]
 mod tests {
-    use super::{builtins_symbol_ty, BytesLiteralType, StringLiteralType, Type, UnionType};
-    use crate::db::tests::TestDb;
-    use crate::program::{Program, SearchPathSettings};
-    use crate::python_version::PythonVersion;
-    use crate::ProgramSettings;
+    use anyhow::Context;
+
+    use ruff_db::files::system_path_to_file;
    use ruff_db::system::{DbWithTestSystem, SystemPathBuf};
-    use test_case::test_case;
+
+    use crate::db::tests::TestDb;
+    use crate::{Program, ProgramSettings, PythonVersion, SearchPathSettings};
+
+    use super::TypeCheckDiagnostics;

    fn setup_db() -> TestDb {
        let db = TestDb::new();
-
-        let src_root = SystemPathBuf::from("/src");
        db.memory_file_system()
-            .create_directory_all(&src_root)
+            .create_directory_all("/src")
            .unwrap();

        Program::from_settings(
            &db,
            &ProgramSettings {
                target_version: PythonVersion::default(),
-                search_paths: SearchPathSettings::new(src_root),
+                search_paths: SearchPathSettings::new(SystemPathBuf::from("/src")),
            },
        )
        .expect("Valid search path settings");
@@ -783,73 +601,91 @@ mod tests {
        db
    }

-    /// A test representation of a type that can be transformed unambiguously into a real Type,
-    /// given a db.
-    #[derive(Debug)]
-    enum Ty {
-        Never,
-        Unknown,
-        Any,
-        IntLiteral(i64),
-        StringLiteral(&'static str),
-        LiteralString,
-        BytesLiteral(&'static str),
-        BuiltinInstance(&'static str),
-        Union(Vec<Ty>),
+    fn assert_diagnostic_messages(diagnostics: &TypeCheckDiagnostics, expected: &[&str]) {
+        let messages: Vec<&str> = diagnostics
+            .iter()
+            .map(|diagnostic| diagnostic.message())
+            .collect();
+        assert_eq!(&messages, expected);
    }

-    impl Ty {
-        fn into_type(self, db: &TestDb) -> Type<'_> {
-            match self {
-                Ty::Never => Type::Never,
-                Ty::Unknown => Type::Unknown,
-                Ty::Any => Type::Any,
-                Ty::IntLiteral(n) => Type::IntLiteral(n),
-                Ty::StringLiteral(s) => {
-                    Type::StringLiteral(StringLiteralType::new(db, (*s).into()))
-                }
-                Ty::LiteralString => Type::LiteralString,
-                Ty::BytesLiteral(s) => {
-                    Type::BytesLiteral(BytesLiteralType::new(db, s.as_bytes().into()))
-                }
-                Ty::BuiltinInstance(s) => builtins_symbol_ty(db, s).to_instance(db),
-                Ty::Union(tys) => {
-                    UnionType::from_elements(db, tys.into_iter().map(|ty| ty.into_type(db)))
-                }
-            }
-        }
+    #[test]
+    fn unresolved_import_statement() -> anyhow::Result<()> {
+        let mut db = setup_db();
+
+        db.write_file("src/foo.py", "import bar\n")
+            .context("Failed to write foo.py")?;
+
+        let foo = system_path_to_file(&db, "src/foo.py").context("Failed to resolve foo.py")?;
+
+        let diagnostics = super::check_types(&db, foo);
+        assert_diagnostic_messages(&diagnostics, &["Cannot resolve import 'bar'."]);
+
+        Ok(())
    }

-    #[test_case(Ty::Unknown, Ty::IntLiteral(1))]
-    #[test_case(Ty::Any, Ty::IntLiteral(1))]
-    #[test_case(Ty::Never, Ty::IntLiteral(1))]
-    #[test_case(Ty::IntLiteral(1), Ty::Unknown)]
-    #[test_case(Ty::IntLiteral(1), Ty::Any)]
-    #[test_case(Ty::IntLiteral(1), Ty::BuiltinInstance("int"))]
-    #[test_case(Ty::StringLiteral("foo"), Ty::BuiltinInstance("str"))]
-    #[test_case(Ty::StringLiteral("foo"), Ty::LiteralString)]
-    #[test_case(Ty::LiteralString, Ty::BuiltinInstance("str"))]
-    #[test_case(Ty::BytesLiteral("foo"), Ty::BuiltinInstance("bytes"))]
-    fn is_assignable_to(from: Ty, to: Ty) {
-        let db = setup_db();
-        assert!(from.into_type(&db).is_assignable_to(&db, to.into_type(&db)));
+    #[test]
+    fn unresolved_import_from_statement() {
+        let mut db = setup_db();
+
+        db.write_file("src/foo.py", "from bar import baz\n")
+            .unwrap();
+        let foo = system_path_to_file(&db, "src/foo.py").unwrap();
+        let diagnostics = super::check_types(&db, foo);
+        assert_diagnostic_messages(&diagnostics, &["Cannot resolve import 'bar'."]);
    }

-    #[test_case(Ty::IntLiteral(1), Ty::BuiltinInstance("str"))]
-    #[test_case(Ty::BuiltinInstance("int"), Ty::BuiltinInstance("str"))]
-    #[test_case(Ty::BuiltinInstance("int"), Ty::IntLiteral(1))]
-    fn is_not_assignable_to(from: Ty, to: Ty) {
-        let db = setup_db();
-        assert!(!from.into_type(&db).is_assignable_to(&db, to.into_type(&db)));
+    #[test]
+    fn unresolved_import_from_resolved_module() {
+        let mut db = setup_db();
+
+        db.write_files([("/src/a.py", ""), ("/src/b.py", "from a import thing")])
+            .unwrap();
+
+        let b_file = system_path_to_file(&db, "/src/b.py").unwrap();
+        let b_file_diagnostics = super::check_types(&db, b_file);
+        assert_diagnostic_messages(&b_file_diagnostics, &["Module 'a' has no member 'thing'"]);
    }

-    #[test_case(
-        Ty::Union(vec![Ty::IntLiteral(1), Ty::IntLiteral(2)]),
-        Ty::Union(vec![Ty::IntLiteral(1), Ty::IntLiteral(2)])
-    )]
-    fn is_equivalent_to(from: Ty, to: Ty) {
-        let db = setup_db();
+    #[test]
+    fn resolved_import_of_symbol_from_unresolved_import() {
+        let mut db = setup_db();

-        assert!(from.into_type(&db).is_equivalent_to(&db, to.into_type(&db)));
+        db.write_files([
+            ("/src/a.py", "import foo as foo"),
+            ("/src/b.py", "from a import foo"),
+        ])
+        .unwrap();
+
+        let a_file = system_path_to_file(&db, "/src/a.py").unwrap();
+        let a_file_diagnostics = super::check_types(&db, a_file);
+        assert_diagnostic_messages(&a_file_diagnostics, &["Cannot resolve import 'foo'."]);
+
+        // Importing the unresolved import into a second first-party file should not trigger
+        // an additional "unresolved import" violation
+        let b_file = system_path_to_file(&db, "/src/b.py").unwrap();
+        let b_file_diagnostics = super::check_types(&db, b_file);
+        assert_eq!(&*b_file_diagnostics, &[]);
+    }
+
+    #[test]
+    fn invalid_callable() {
+        let mut db = setup_db();
+
+        db.write_dedented(
+            "src/a.py",
+            "
+            nonsense = 123
+            x = nonsense()
+            ",
+        )
+        .unwrap();
+
+        let a_file = system_path_to_file(&db, "/src/a.py").unwrap();
+        let a_file_diagnostics = super::check_types(&db, a_file);
+        assert_diagnostic_messages(
+            &a_file_diagnostics,
+            &["Object of type 'Literal[123]' is not callable"],
+        );
    }
 }
--- a/crates/red_knot_python_semantic/src/types/builder.rs
+++ b/crates/red_knot_python_semantic/src/types/builder.rs
@@ -25,10 +25,13 @@
 //!   * 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::{builtins_symbol_ty, IntersectionType, Type, UnionType};
+
+use crate::types::{IntersectionType, Type, UnionType};
 use crate::{Db, FxOrderSet};
 use ordermap::set::MutableValues;

+use super::builtins_symbol_ty_by_name;
+
 pub(crate) struct UnionBuilder<'db> {
    elements: FxOrderSet<Type<'db>>,
    db: &'db dyn Db,
@@ -65,7 +68,7 @@ impl<'db> UnionBuilder<'db> {
        if let Some(true_index) = self.elements.get_index_of(&Type::BooleanLiteral(true)) {
            if self.elements.contains(&Type::BooleanLiteral(false)) {
                *self.elements.get_index_mut2(true_index).unwrap() =
-                    builtins_symbol_ty(self.db, "bool");
+                    builtins_symbol_ty_by_name(self.db, "bool");
                self.elements.remove(&Type::BooleanLiteral(false));
            }
        }
@@ -169,12 +172,11 @@ impl<'db> IntersectionBuilder<'db> {
        if self.intersections.len() == 1 {
            self.intersections.pop().unwrap().build(self.db)
        } else {
-            UnionType::from_elements(
-                self.db,
-                self.intersections
-                    .into_iter()
-                    .map(|inner| inner.build(self.db)),
-            )
+            let mut builder = UnionBuilder::new(self.db);
+            for inner in self.intersections {
+                builder = builder.add(inner.build(self.db));
+            }
+            builder.build()
        }
    }
 }
@@ -272,11 +274,11 @@ impl<'db> InnerIntersectionBuilder<'db> {

 #[cfg(test)]
 mod tests {
-    use super::{IntersectionBuilder, IntersectionType, Type, UnionType};
+    use super::{IntersectionBuilder, IntersectionType, Type, UnionBuilder, 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::types::builtins_symbol_ty_by_name;
    use crate::ProgramSettings;
    use ruff_db::system::{DbWithTestSystem, SystemPathBuf};

@@ -311,7 +313,11 @@ mod tests {
        let db = setup_db();
        let t0 = Type::IntLiteral(0);
        let t1 = Type::IntLiteral(1);
-        let union = UnionType::from_elements(&db, [t0, t1]).expect_union();
+        let union = UnionBuilder::new(&db)
+            .add(t0)
+            .add(t1)
+            .build()
+            .expect_union();

        assert_eq!(union.elements_vec(&db), &[t0, t1]);
    }
@@ -320,7 +326,8 @@ mod tests {
    fn build_union_single() {
        let db = setup_db();
        let t0 = Type::IntLiteral(0);
-        let ty = UnionType::from_elements(&db, [t0]);
+        let ty = UnionBuilder::new(&db).add(t0).build();
+
        assert_eq!(ty, t0);
    }

@@ -328,6 +335,7 @@ mod tests {
    fn build_union_empty() {
        let db = setup_db();
        let ty = UnionBuilder::new(&db).build();
+
        assert_eq!(ty, Type::Never);
    }

@@ -335,24 +343,36 @@ mod tests {
    fn build_union_never() {
        let db = setup_db();
        let t0 = Type::IntLiteral(0);
-        let ty = UnionType::from_elements(&db, [t0, Type::Never]);
+        let ty = UnionBuilder::new(&db).add(t0).add(Type::Never).build();
+
        assert_eq!(ty, t0);
    }

    #[test]
    fn build_union_bool() {
        let db = setup_db();
-        let bool_ty = builtins_symbol_ty(&db, "bool");
+        let bool_ty = builtins_symbol_ty_by_name(&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();
+        let union = UnionBuilder::new(&db)
+            .add(t0)
+            .add(t1)
+            .add(t3)
+            .build()
+            .expect_union();
        assert_eq!(union.elements_vec(&db), &[t0, t3]);
+        let union = UnionBuilder::new(&db)
+            .add(t0)
+            .add(t1)
+            .add(t2)
+            .add(t3)
+            .build()
+            .expect_union();

-        let union = UnionType::from_elements(&db, [t0, t1, t2, t3]).expect_union();
        assert_eq!(union.elements_vec(&db), &[bool_ty, t3]);
    }

@@ -362,8 +382,12 @@ mod tests {
        let t0 = Type::IntLiteral(0);
        let t1 = Type::IntLiteral(1);
        let t2 = Type::IntLiteral(2);
-        let u1 = UnionType::from_elements(&db, [t0, t1]);
-        let union = UnionType::from_elements(&db, [u1, t2]).expect_union();
+        let u1 = UnionBuilder::new(&db).add(t0).add(t1).build();
+        let union = UnionBuilder::new(&db)
+            .add(u1)
+            .add(t2)
+            .build()
+            .expect_union();

        assert_eq!(union.elements_vec(&db), &[t0, t1, t2]);
    }
@@ -439,7 +463,7 @@ mod tests {
        let t0 = Type::IntLiteral(0);
        let t1 = Type::IntLiteral(1);
        let ta = Type::Any;
-        let u0 = UnionType::from_elements(&db, [t0, t1]);
+        let u0 = UnionBuilder::new(&db).add(t0).add(t1).build();

        let union = IntersectionBuilder::new(&db)
            .add_positive(ta)
--- a/crates/red_knot_python_semantic/src/types/display.rs
+++ b/crates/red_knot_python_semantic/src/types/display.rs
@@ -86,23 +86,6 @@ impl std::fmt::Display for DisplayRepresentation<'_> {

                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 {
-                    let mut first = true;
-                    for element in &**elements {
-                        if !first {
-                            f.write_str(", ")?;
-                        }
-                        first = false;
-                        element.display(self.db).fmt(f)?;
-                    }
-                }
-                f.write_str("]")
-            }
        }
    }
 }
@@ -253,7 +236,9 @@ mod tests {
    use ruff_db::system::{DbWithTestSystem, SystemPathBuf};

    use crate::db::tests::TestDb;
-    use crate::types::{global_symbol_ty, BytesLiteralType, StringLiteralType, Type, UnionType};
+    use crate::types::{
+        global_symbol_ty_by_name, BytesLiteralType, StringLiteralType, Type, UnionBuilder,
+    };
    use crate::{Program, ProgramSettings, PythonVersion, SearchPathSettings};

    fn setup_db() -> TestDb {
@@ -295,23 +280,26 @@ mod tests {
        )?;
        let mod_file = system_path_to_file(&db, "src/main.py").expect("Expected file to exist.");

-        let union_elements = &[
+        let vec: Vec<Type<'_>> = vec![
            Type::Unknown,
            Type::IntLiteral(-1),
-            global_symbol_ty(&db, mod_file, "A"),
+            global_symbol_ty_by_name(&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"),
+            global_symbol_ty_by_name(&db, mod_file, "foo"),
+            global_symbol_ty_by_name(&db, mod_file, "bar"),
+            global_symbol_ty_by_name(&db, mod_file, "B"),
            Type::BooleanLiteral(true),
            Type::None,
        ];
-        let union = UnionType::from_elements(&db, union_elements).expect_union();
+        let builder = vec.iter().fold(UnionBuilder::new(&db), |builder, literal| {
+            builder.add(*literal)
+        });
+        let union = builder.build().expect_union();
        let display = format!("{}", union.display(&db));
        assert_eq!(
            display,
--- 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
@@ -1,10 +1,9 @@
 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};
+use crate::types::{infer_expression_types, IntersectionBuilder, Type, TypeInference};
 use crate::Db;
 use ruff_python_ast as ast;
 use rustc_hash::FxHashMap;
@@ -28,114 +27,62 @@ 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,
-    constraint: Constraint<'db>,
+    test: Expression<'db>,
    definition: Definition<'db>,
 ) -> Option<Type<'db>> {
-    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(),
-    }
+    all_narrowing_constraints(db, test)
+        .get(&definition.symbol(db))
+        .copied()
 }

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

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

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

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

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

-    fn add_expr_compare(&mut self, expr_compare: &ast::ExprCompare, expression: Expression<'db>) {
+    fn inference(&self) -> &'db TypeInference<'db> {
+        infer_expression_types(self.db, self.expression)
+    }
+
+    fn add_expr_compare(&mut self, expr_compare: &ast::ExprCompare) {
        let ast::ExprCompare {
            range: _,
            left,
@@ -152,7 +99,7 @@ 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 = infer_expression_types(self.db, expression);
+            let inference = self.inference();
            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) {
@@ -165,22 +112,4 @@ 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/ruff/Cargo.toml
+++ b/crates/ruff/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "ruff"
-version = "0.6.5"
+version = "0.6.3"
 publish = true
 authors = { workspace = true }
 edition = { workspace = true }
--- a/crates/ruff_benchmark/Cargo.toml
+++ b/crates/ruff_benchmark/Cargo.toml
@@ -66,4 +66,4 @@ codspeed = ["codspeed-criterion-compat"]
 mimalloc = { workspace = true }

 [target.'cfg(all(not(target_os = "windows"), not(target_os = "openbsd"), any(target_arch = "x86_64", target_arch = "aarch64", target_arch = "powerpc64")))'.dev-dependencies]
-tikv-jemallocator = { workspace = true, features = ["unprefixed_malloc_on_supported_platforms"] }
+tikv-jemallocator = { workspace = true }
--- a/crates/ruff_benchmark/benches/linter.rs
+++ b/crates/ruff_benchmark/benches/linter.rs
@@ -28,24 +28,6 @@ static GLOBAL: mimalloc::MiMalloc = mimalloc::MiMalloc;
 #[global_allocator]
 static GLOBAL: tikv_jemallocator::Jemalloc = tikv_jemallocator::Jemalloc;

-// Disable decay after 10s because it can show up as *random* slow allocations
-// in benchmarks. We don't need purging in benchmarks because it isn't important
-// to give unallocated pages back to the OS.
-// https://jemalloc.net/jemalloc.3.html#opt.dirty_decay_ms
-#[cfg(all(
-    not(target_os = "windows"),
-    not(target_os = "openbsd"),
-    any(
-        target_arch = "x86_64",
-        target_arch = "aarch64",
-        target_arch = "powerpc64"
-    )
-))]
-#[allow(non_upper_case_globals)]
-#[export_name = "malloc_conf"]
-#[allow(unsafe_code)]
-pub static malloc_conf: &[u8] = b"dirty_decay_ms:-1,muzzy_decay_ms:-1\0";
-
 fn create_test_cases() -> Result<Vec<TestCase>, TestFileDownloadError> {
    Ok(vec![
        TestCase::fast(TestFile::try_download("numpy/globals.py", "https://raw.githubusercontent.com/numpy/numpy/89d64415e349ca75a25250f22b874aa16e5c0973/numpy/_globals.py")?),
--- a/crates/ruff_benchmark/benches/red_knot.rs
+++ b/crates/ruff_benchmark/benches/red_knot.rs
@@ -23,7 +23,6 @@ const TOMLLIB_312_URL: &str = "https://raw.githubusercontent.com/python/cpython/

 // The failed import from 'collections.abc' is due to lack of support for 'import *'.
 static EXPECTED_DIAGNOSTICS: &[&str] = &[
-    "/src/tomllib/_parser.py:5:24: Module '__future__' has no member 'annotations'",
    "/src/tomllib/_parser.py:7:29: Module 'collections.abc' has no member 'Iterable'",
    "Line 69 is too long (89 characters)",
    "Use double quotes for strings",
@@ -33,6 +32,7 @@ static EXPECTED_DIAGNOSTICS: &[&str] = &[
    "Use double quotes for strings",
    "Use double quotes for strings",
    "Use double quotes for strings",
+    "/src/tomllib/_parser.py:628:75: Name 'e' used when not defined.",
 ];

 fn get_test_file(name: &str) -> TestFile {
--- a/crates/ruff_linter/Cargo.toml
+++ b/crates/ruff_linter/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "ruff_linter"
-version = "0.6.5"
+version = "0.6.3"
 publish = false
 authors = { workspace = true }
 edition = { workspace = true }
@@ -73,7 +73,7 @@ unicode-normalization = { workspace = true }
 url = { workspace = true }

 [dev-dependencies]
-insta = { workspace = true, features = ["filters", "json", "redactions"] }
+insta = { workspace = true }
 test-case = { workspace = true }
 # Disable colored output in tests
 colored = { workspace = true, features = ["no-color"] }
--- a/crates/ruff_linter/resources/test/fixtures/eradicate/ERA001.py
+++ b/crates/ruff_linter/resources/test/fixtures/eradicate/ERA001.py
@@ -57,18 +57,7 @@ dictionary = {
 # ]
 # ///

-# Script tag with multiple closing tags (OK)
-# /// script
-# [tool.uv]
-# extra-index-url = ["https://pypi.org/simple", """\
-# https://example.com/
-# ///
-# """
-# ]
-# ///
-print(1)
-
-# Script tag without a closing tag (Error)
+# Script tag without a closing tag (OK)

 # /// script
 # requires-python = ">=3.11"
--- a/crates/ruff_linter/resources/test/fixtures/pydoclint/DOC201_google.py
+++ b/crates/ruff_linter/resources/test/fixtures/pydoclint/DOC201_google.py
@@ -207,10 +207,3 @@ def foo(s: str) -> str | None:
        s (str): A string.
    """
    return None
-
-
-class Spam:
-    # OK
-    def __new__(cls) -> 'Spam':
-        """New!!"""
-        return cls()
--- a/crates/ruff_linter/resources/test/fixtures/pylint/bad_dunder_method_name.py
+++ b/crates/ruff_linter/resources/test/fixtures/pylint/bad_dunder_method_name.py
@@ -94,9 +94,6 @@ class Apples:
    def __mro_entries__(self, bases):
        pass

-    # Removed with Python 3
-    def __unicode__(self):
-        pass

 def __foo_bar__():  # this is not checked by the [bad-dunder-name] rule
    ...
--- a/crates/ruff_linter/resources/test/fixtures/refurb/FURB188.py
+++ b/crates/ruff_linter/resources/test/fixtures/refurb/FURB188.py
@@ -1,154 +0,0 @@
-# Test suite from Refurb
-# See https://github.com/dosisod/refurb/blob/db02242b142285e615a664a8d3324470bb711306/test/data/err_188.py
-
-# these should match
-
-def remove_extension_via_slice(filename: str) -> str:
-    if filename.endswith(".txt"):
-        filename = filename[:-4]
-
-    return filename
-
-
-def remove_extension_via_slice_len(filename: str, extension: str) -> str:
-    if filename.endswith(extension):
-        filename = filename[:-len(extension)]
-
-    return filename
-
-
-def remove_extension_via_ternary(filename: str) -> str:
-    return filename[:-4] if filename.endswith(".txt") else filename
-
-
-def remove_extension_via_ternary_with_len(filename: str, extension: str) -> str:
-    return filename[:-len(extension)] if filename.endswith(extension) else filename
-
-
-def remove_prefix(filename: str) -> str:
-    return filename[4:] if filename.startswith("abc-") else filename
-
-
-def remove_prefix_via_len(filename: str, prefix: str) -> str:
-    return filename[len(prefix):] if filename.startswith(prefix) else filename
-
-
-# these should not
-
-def remove_extension_with_mismatched_len(filename: str) -> str:
-    if filename.endswith(".txt"):
-        filename = filename[:3]
-
-    return filename
-
-
-def remove_extension_assign_to_different_var(filename: str) -> str:
-    if filename.endswith(".txt"):
-        other_var = filename[:-4]
-
-    return filename
-
-
-def remove_extension_with_multiple_stmts(filename: str) -> str:
-    if filename.endswith(".txt"):
-        print("do some work")
-
-        filename = filename[:-4]
-
-    if filename.endswith(".txt"):
-        filename = filename[:-4]
-
-        print("do some work")
-
-    return filename
-
-
-def remove_extension_from_unrelated_var(filename: str) -> str:
-    xyz = "abc.txt"
-
-    if filename.endswith(".txt"):
-        filename = xyz[:-4]
-
-    return filename
-
-
-def remove_extension_in_elif(filename: str) -> str:
-    if filename:
-        pass
-
-    elif filename.endswith(".txt"):
-        filename = filename[:-4]
-
-    return filename
-
-
-def remove_extension_in_multiple_elif(filename: str) -> str:
-    if filename:
-        pass
-
-    elif filename:
-        pass
-
-    elif filename.endswith(".txt"):
-        filename = filename[:-4]
-
-    return filename
-
-
-def remove_extension_in_if_with_else(filename: str) -> str:
-    if filename.endswith(".txt"):
-        filename = filename[:-4]
-
-    else:
-        pass
-
-    return filename
-
-
-def remove_extension_ternary_name_mismatch(filename: str):
-    xyz = ""
-
-    _ = xyz[:-4] if filename.endswith(".txt") else filename
-    _ = filename[:-4] if xyz.endswith(".txt") else filename
-    _ = filename[:-4] if filename.endswith(".txt") else xyz
-
-
-def remove_extension_slice_amount_mismatch(filename: str) -> None:
-    extension = ".txt"
-
-    _ = filename[:-1] if filename.endswith(".txt") else filename
-    _ = filename[:-1] if filename.endswith(extension) else filename
-    _ = filename[:-len("")] if filename.endswith(extension) else filename
-
-
-def remove_prefix_size_mismatch(filename: str) -> str:
-    return filename[3:] if filename.startswith("abc-") else filename
-
-
-def remove_prefix_name_mismatch(filename: str) -> None:
-    xyz = ""
-
-    _ = xyz[4:] if filename.startswith("abc-") else filename
-    _ = filename[4:] if xyz.startswith("abc-") else filename
-    _ = filename[4:] if filename.startswith("abc-") else xyz
-
-# ---- End of refurb test suite ---- #
-
-# ---- Begin ruff specific test suite --- #
-
-# these should be linted
-
-def remove_suffix_multiple_attribute_expr() -> None:
-    import foo.bar
-
-    SUFFIX = "suffix"
-
-    x = foo.bar.baz[:-len(SUFFIX)] if foo.bar.baz.endswith(SUFFIX) else foo.bar.baz
-
-def remove_prefix_comparable_literal_expr() -> None:
-    return ("abc" "def")[3:] if ("abc" "def").startswith("abc") else "abc" "def"
-
-def shadow_builtins(filename: str, extension: str) -> None:
-    from builtins import len as builtins_len
-
-    return filename[:-builtins_len(extension)] if filename.endswith(extension) else filename
--- a/crates/ruff_linter/resources/test/fixtures/ruff/RUF032.py
+++ b/crates/ruff_linter/resources/test/fixtures/ruff/RUF032.py
@@ -50,13 +50,6 @@ a = 10.0

 val = Decimal(a)

-# See https://github.com/astral-sh/ruff/issues/13258
-val = Decimal(~4.0) # Skip
-
-val = Decimal(++4.0) # Suggest `Decimal("4.0")`
-
-val = Decimal(-+--++--4.0) # Suggest `Decimal("-4.0")` 
-

 # Tests with shadowed name
 class Decimal():
--- a/crates/ruff_linter/resources/test/fixtures/ruff/RUF034.py
+++ b/crates/ruff_linter/resources/test/fixtures/ruff/RUF034.py
@@ -1,11 +0,0 @@
-# Valid
-x = 1 if True else 2
-
-# Invalid
-x = 1 if True else 1
-
-# Invalid
-x = "a" if True else "a"
-
-# Invalid
-x = 0.1 if False else 0.1
--- a/crates/ruff_linter/src/checkers/ast/analyze/expression.rs
+++ b/crates/ruff_linter/src/checkers/ast/analyze/expression.rs
@@ -1404,12 +1404,6 @@ pub(crate) fn expression(expr: &Expr, checker: &mut Checker) {
            if checker.enabled(Rule::IfExpInsteadOfOrOperator) {
                refurb::rules::if_exp_instead_of_or_operator(checker, if_exp);
            }
-            if checker.enabled(Rule::UselessIfElse) {
-                ruff::rules::useless_if_else(checker, if_exp);
-            }
-            if checker.enabled(Rule::SliceToRemovePrefixOrSuffix) {
-                refurb::rules::slice_to_remove_affix_expr(checker, if_exp);
-            }
        }
        Expr::ListComp(
            comp @ ast::ExprListComp {
--- a/crates/ruff_linter/src/checkers/ast/analyze/statement.rs
+++ b/crates/ruff_linter/src/checkers/ast/analyze/statement.rs
@@ -1178,9 +1178,6 @@ pub(crate) fn statement(stmt: &Stmt, checker: &mut Checker) {
            if checker.enabled(Rule::CheckAndRemoveFromSet) {
                refurb::rules::check_and_remove_from_set(checker, if_);
            }
-            if checker.enabled(Rule::SliceToRemovePrefixOrSuffix) {
-                refurb::rules::slice_to_remove_affix_stmt(checker, if_);
-            }
            if checker.enabled(Rule::TooManyBooleanExpressions) {
                pylint::rules::too_many_boolean_expressions(checker, if_);
            }
--- a/crates/ruff_linter/src/checkers/ast/analyze/unresolved_references.rs
+++ b/crates/ruff_linter/src/checkers/ast/analyze/unresolved_references.rs
@@ -1,6 +1,5 @@
 use ruff_diagnostics::Diagnostic;
 use ruff_python_semantic::Exceptions;
-use ruff_python_stdlib::builtins::version_builtin_was_added;

 use crate::checkers::ast::Checker;
 use crate::codes::Rule;
@@ -36,12 +35,9 @@ pub(crate) fn unresolved_references(checker: &mut Checker) {
                    }
                }

-                let symbol_name = reference.name(checker.locator);
-
                checker.diagnostics.push(Diagnostic::new(
                    pyflakes::rules::UndefinedName {
-                        name: symbol_name.to_string(),
-                        minor_version_builtin_added: version_builtin_was_added(symbol_name),
+                        name: reference.name(checker.locator).to_string(),
                    },
                    reference.range(),
                ));
--- a/crates/ruff_linter/src/checkers/ast/mod.rs
+++ b/crates/ruff_linter/src/checkers/ast/mod.rs
@@ -1951,25 +1951,20 @@ impl<'a> Checker<'a> {
    }

    fn bind_builtins(&mut self) {
-        let mut bind_builtin = |builtin| {
-            // Add the builtin to the scope.
-            let binding_id = self.semantic.push_builtin();
-            let scope = self.semantic.global_scope_mut();
-            scope.add(builtin, binding_id);
-        };
-
        let standard_builtins = python_builtins(
            self.settings.target_version.minor(),
            self.source_type.is_ipynb(),
        );
-        for builtin in standard_builtins {
-            bind_builtin(builtin);
-        }
-        for builtin in MAGIC_GLOBALS {
-            bind_builtin(builtin);
-        }
-        for builtin in &self.settings.builtins {
-            bind_builtin(builtin);
+        for builtin in standard_builtins
+            .iter()
+            .chain(MAGIC_GLOBALS.iter())
+            .copied()
+            .chain(self.settings.builtins.iter().map(String::as_str))
+        {
+            // Add the builtin to the scope.
+            let binding_id = self.semantic.push_builtin();
+            let scope = self.semantic.global_scope_mut();
+            scope.add(builtin, binding_id);
        }
    }

--- a/crates/ruff_linter/src/checkers/tokens.rs
+++ b/crates/ruff_linter/src/checkers/tokens.rs
@@ -63,7 +63,7 @@ pub(crate) fn check_tokens(
            ruff::rules::ambiguous_unicode_character_comment(
                &mut diagnostics,
                locator,
-                range,
+                *range,
                settings,
            );
        }
@@ -154,13 +154,7 @@ pub(crate) fn check_tokens(
        Rule::ShebangNotFirstLine,
        Rule::ShebangMissingPython,
    ]) {
-        flake8_executable::rules::from_tokens(
-            &mut diagnostics,
-            path,
-            locator,
-            comment_ranges,
-            settings,
-        );
+        flake8_executable::rules::from_tokens(&mut diagnostics, path, locator, comment_ranges);
    }

    if settings.rules.any_enabled(&[
--- a/crates/ruff_linter/src/codes.rs
+++ b/crates/ruff_linter/src/codes.rs
@@ -961,7 +961,6 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
        (Ruff, "031") => (RuleGroup::Preview, rules::ruff::rules::IncorrectlyParenthesizedTupleInSubscript),
        (Ruff, "032") => (RuleGroup::Preview, rules::ruff::rules::DecimalFromFloatLiteral),
        (Ruff, "033") => (RuleGroup::Preview, rules::ruff::rules::PostInitDefault),
-        (Ruff, "034") => (RuleGroup::Preview, rules::ruff::rules::UselessIfElse),
        (Ruff, "100") => (RuleGroup::Stable, rules::ruff::rules::UnusedNOQA),
        (Ruff, "101") => (RuleGroup::Stable, rules::ruff::rules::RedirectedNOQA),

@@ -1067,7 +1066,6 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
        (Refurb, "180") => (RuleGroup::Preview, rules::refurb::rules::MetaClassABCMeta),
        (Refurb, "181") => (RuleGroup::Stable, rules::refurb::rules::HashlibDigestHex),
        (Refurb, "187") => (RuleGroup::Stable, rules::refurb::rules::ListReverseCopy),
-        (Refurb, "188") => (RuleGroup::Preview, rules::refurb::rules::SliceToRemovePrefixOrSuffix),
        (Refurb, "192") => (RuleGroup::Preview, rules::refurb::rules::SortedMinMax),

        // flake8-logging
--- a/crates/ruff_linter/src/message/sarif.rs
+++ b/crates/ruff_linter/src/message/sarif.rs
@@ -1,9 +1,9 @@
-use std::collections::HashSet;
 use std::io::Write;

 use anyhow::Result;
 use serde::{Serialize, Serializer};
 use serde_json::json;
+use strum::IntoEnumIterator;

 use ruff_source_file::OneIndexed;

@@ -27,10 +27,6 @@ impl Emitter for SarifEmitter {
            .map(SarifResult::from_message)
            .collect::<Result<Vec<_>>>()?;

-        let unique_rules: HashSet<_> = results.iter().filter_map(|result| result.rule).collect();
-        let mut rules: Vec<SarifRule> = unique_rules.into_iter().map(SarifRule::from).collect();
-        rules.sort_by(|a, b| a.code.cmp(&b.code));
-
        let output = json!({
            "$schema": "https://json.schemastore.org/sarif-2.1.0.json",
            "version": "2.1.0",
@@ -39,7 +35,7 @@ impl Emitter for SarifEmitter {
                    "driver": {
                        "name": "ruff",
                        "informationUri": "https://github.com/astral-sh/ruff",
-                        "rules": rules,
+                        "rules": Rule::iter().map(SarifRule::from).collect::<Vec<_>>(),
                        "version": VERSION.to_string(),
                    }
                },
@@ -186,6 +182,7 @@ impl Serialize for SarifResult {

 #[cfg(test)]
 mod tests {
+
    use crate::message::tests::{
        capture_emitter_output, create_messages, create_syntax_error_messages,
    };
@@ -212,11 +209,16 @@ mod tests {
    #[test]
    fn test_results() {
        let content = get_output();
-        let value = serde_json::from_str::<serde_json::Value>(&content).unwrap();
-
-        insta::assert_json_snapshot!(value, {
-            ".runs[0].tool.driver.version" => "[VERSION]",
-            ".runs[0].results[].locations[].physicalLocation.artifactLocation.uri" => "[URI]",
-        });
+        let sarif = serde_json::from_str::<serde_json::Value>(content.as_str()).unwrap();
+        let rules = sarif["runs"][0]["tool"]["driver"]["rules"]
+            .as_array()
+            .unwrap();
+        let results = sarif["runs"][0]["results"].as_array().unwrap();
+        assert_eq!(results.len(), 3);
+        assert_eq!(
+            results[0]["message"]["text"].as_str().unwrap(),
+            "`os` imported but unused"
+        );
+        assert!(rules.len() > 3);
    }
 }
--- a/crates/ruff_linter/src/message/snapshots/ruff_lintermessagesariftestsresults.snap
+++ b/crates/ruff_linter/src/message/snapshots/ruff_lintermessagesariftestsresults.snap
@@ -1,146 +0,0 @@
---
-source: crates/ruff_linter/src/message/sarif.rs
-expression: value
---
-{
-  "$schema": "https://json.schemastore.org/sarif-2.1.0.json",
-  "runs": [
-    {
-      "results": [
-        {
-          "level": "error",
-          "locations": [
-            {
-              "physicalLocation": {
-                "artifactLocation": {
-                  "uri": "[URI]"
-                },
-                "region": {
-                  "endColumn": 10,
-                  "endLine": 1,
-                  "startColumn": 8,
-                  "startLine": 1
-                }
-              }
-            }
-          ],
-          "message": {
-            "text": "`os` imported but unused"
-          },
-          "ruleId": "F401"
-        },
-        {
-          "level": "error",
-          "locations": [
-            {
-              "physicalLocation": {
-                "artifactLocation": {
-                  "uri": "[URI]"
-                },
-                "region": {
-                  "endColumn": 6,
-                  "endLine": 6,
-                  "startColumn": 5,
-                  "startLine": 6
-                }
-              }
-            }
-          ],
-          "message": {
-            "text": "Local variable `x` is assigned to but never used"
-          },
-          "ruleId": "F841"
-        },
-        {
-          "level": "error",
-          "locations": [
-            {
-              "physicalLocation": {
-                "artifactLocation": {
-                  "uri": "[URI]"
-                },
-                "region": {
-                  "endColumn": 5,
-                  "endLine": 1,
-                  "startColumn": 4,
-                  "startLine": 1
-                }
-              }
-            }
-          ],
-          "message": {
-            "text": "Undefined name `a`"
-          },
-          "ruleId": "F821"
-        }
-      ],
-      "tool": {
-        "driver": {
-          "informationUri": "https://github.com/astral-sh/ruff",
-          "name": "ruff",
-          "rules": [
-            {
-              "fullDescription": {
-                "text": "## What it does\nChecks for unused imports.\n\n## Why is this bad?\nUnused imports add a performance overhead at runtime, and risk creating\nimport cycles. They also increase the cognitive load of reading the code.\n\nIf an import statement is used to check for the availability or existence\nof a module, consider using `importlib.util.find_spec` instead.\n\nIf an import statement is used to re-export a symbol as part of a module's\npublic interface, consider using a \"redundant\" import alias, which\ninstructs Ruff (and other tools) to respect the re-export, and avoid\nmarking it as unused, as in:\n\n```python\nfrom module import member as member\n```\n\nAlternatively, you can use `__all__` to declare a symbol as part of the module's\ninterface, as in:\n\n```python\n# __init__.py\nimport some_module\n\n__all__ = [\"some_module\"]\n```\n\n## Fix safety\n\nFixes to remove unused imports are safe, except in `__init__.py` files.\n\nApplying fixes to `__init__.py` files is currently in preview. The fix offered depends on the\ntype of the unused import. Ruff will suggest a safe fix to export first-party imports with\neither a redundant alias or, if already present in the file, an `__all__` entry. If multiple\n`__all__` declarations are present, Ruff will not offer a fix. Ruff will suggest an unsafe fix\nto remove third-party and standard library imports -- the fix is unsafe because the module's\ninterface changes.\n\n## Example\n\n```python\nimport numpy as np  # unused import\n\n\ndef area(radius):\n    return 3.14 * radius**2\n```\n\nUse instead:\n\n```python\ndef area(radius):\n    return 3.14 * radius**2\n```\n\nTo check the availability of a module, use `importlib.util.find_spec`:\n\n```python\nfrom importlib.util import find_spec\n\nif find_spec(\"numpy\") is not None:\n    print(\"numpy is installed\")\nelse:\n    print(\"numpy is not installed\")\n```\n\n## Options\n- `lint.ignore-init-module-imports`\n\n## References\n- [Python documentation: `import`](https://docs.python.org/3/reference/simple_stmts.html#the-import-statement)\n- [Python documentation: `importlib.util.find_spec`](https://docs.python.org/3/library/importlib.html#importlib.util.find_spec)\n- [Typing documentation: interface conventions](https://typing.readthedocs.io/en/latest/source/libraries.html#library-interface-public-and-private-symbols)\n"
-              },
-              "help": {
-                "text": "`{name}` imported but unused; consider using `importlib.util.find_spec` to test for availability"
-              },
-              "helpUri": "https://docs.astral.sh/ruff/rules/unused-import",
-              "id": "F401",
-              "properties": {
-                "id": "F401",
-                "kind": "Pyflakes",
-                "name": "unused-import",
-                "problem.severity": "error"
-              },
-              "shortDescription": {
-                "text": "`{name}` imported but unused; consider using `importlib.util.find_spec` to test for availability"
-              }
-            },
-            {
-              "fullDescription": {
-                "text": "## What it does\nChecks for uses of undefined names.\n\n## Why is this bad?\nAn undefined name is likely to raise `NameError` at runtime.\n\n## Example\n```python\ndef double():\n    return n * 2  # raises `NameError` if `n` is undefined when `double` is called\n```\n\nUse instead:\n```python\ndef double(n):\n    return n * 2\n```\n\n## Options\n- [`target-version`]: Can be used to configure which symbols Ruff will understand\n  as being available in the `builtins` namespace.\n\n## References\n- [Python documentation: Naming and binding](https://docs.python.org/3/reference/executionmodel.html#naming-and-binding)\n"
-              },
-              "help": {
-                "text": "Undefined name `{name}`. {tip}"
-              },
-              "helpUri": "https://docs.astral.sh/ruff/rules/undefined-name",
-              "id": "F821",
-              "properties": {
-                "id": "F821",
-                "kind": "Pyflakes",
-                "name": "undefined-name",
-                "problem.severity": "error"
-              },
-              "shortDescription": {
-                "text": "Undefined name `{name}`. {tip}"
-              }
-            },
-            {
-              "fullDescription": {
-                "text": "## What it does\nChecks for the presence of unused variables in function scopes.\n\n## Why is this bad?\nA variable that is defined but not used is likely a mistake, and should\nbe removed to avoid confusion.\n\nIf a variable is intentionally defined-but-not-used, it should be\nprefixed with an underscore, or some other value that adheres to the\n[`lint.dummy-variable-rgx`] pattern.\n\nUnder [preview mode](https://docs.astral.sh/ruff/preview), this rule also\ntriggers on unused unpacked assignments (for example, `x, y = foo()`).\n\n## Example\n```python\ndef foo():\n    x = 1\n    y = 2\n    return x\n```\n\nUse instead:\n```python\ndef foo():\n    x = 1\n    return x\n```\n\n## Options\n- `lint.dummy-variable-rgx`\n"
-              },
-              "help": {
-                "text": "Local variable `{name}` is assigned to but never used"
-              },
-              "helpUri": "https://docs.astral.sh/ruff/rules/unused-variable",
-              "id": "F841",
-              "properties": {
-                "id": "F841",
-                "kind": "Pyflakes",
-                "name": "unused-variable",
-                "problem.severity": "error"
-              },
-              "shortDescription": {
-                "text": "Local variable `{name}` is assigned to but never used"
-              }
-            }
-          ],
-          "version": "[VERSION]"
-        }
-      }
-    }
-  ],
-  "version": "2.1.0"
-}
--- a/crates/ruff_linter/src/noqa.rs
+++ b/crates/ruff_linter/src/noqa.rs
@@ -361,7 +361,7 @@ impl<'a> FileNoqaDirectives<'a> {
        let mut lines = vec![];

        for range in comment_ranges {
-            match ParsedFileExemption::try_extract(&contents[range]) {
+            match ParsedFileExemption::try_extract(&contents[*range]) {
                Err(err) => {
                    #[allow(deprecated)]
                    let line = locator.compute_line_index(range.start());
@@ -403,7 +403,7 @@ impl<'a> FileNoqaDirectives<'a> {
                    };

                    lines.push(FileNoqaDirectiveLine {
-                        range,
+                        range: *range,
                        parsed_file_exemption: exemption,
                        matches,
                    });
@@ -922,7 +922,7 @@ impl<'a> NoqaDirectives<'a> {
        let mut directives = Vec::new();

        for range in comment_ranges {
-            match Directive::try_extract(locator.slice(range), range.start()) {
+            match Directive::try_extract(locator.slice(*range), range.start()) {
                Err(err) => {
                    #[allow(deprecated)]
                    let line = locator.compute_line_index(range.start());
--- a/crates/ruff_linter/src/rules/eradicate/rules/commented_out_code.rs
+++ b/crates/ruff_linter/src/rules/eradicate/rules/commented_out_code.rs
@@ -1,9 +1,9 @@
-use crate::settings::LinterSettings;
 use ruff_diagnostics::{Diagnostic, Edit, Fix, FixAvailability, Violation};
 use ruff_macros::{derive_message_formats, violation};
 use ruff_python_trivia::CommentRanges;
-use ruff_source_file::{Locator, UniversalNewlineIterator};
-use ruff_text_size::TextRange;
+use ruff_source_file::Locator;
+
+use crate::settings::LinterSettings;

 use super::super::detection::comment_contains_code;

@@ -50,110 +50,40 @@ pub(crate) fn commented_out_code(
    comment_ranges: &CommentRanges,
    settings: &LinterSettings,
 ) {
-    let mut comments = comment_ranges.into_iter().peekable();
-    // Iterate over all comments in the document.
-    while let Some(range) = comments.next() {
-        let line = locator.line(range.start());
+    // Skip comments within `/// script` tags.
+    let mut in_script_tag = false;

-        if is_script_tag_start(line) {
-            if skip_script_comments(range, &mut comments, locator) {
-                continue;
+    // Iterate over all comments in the document.
+    for range in comment_ranges {
+        let line = locator.lines(*range);
+
+        // Detect `/// script` tags.
+        if in_script_tag {
+            if is_script_tag_end(line) {
+                in_script_tag = false;
            }
+        } else {
+            if is_script_tag_start(line) {
+                in_script_tag = true;
+            }
+        }
+
+        // Skip comments within `/// script` tags.
+        if in_script_tag {
+            continue;
        }

        // Verify that the comment is on its own line, and that it contains code.
        if is_own_line_comment(line) && comment_contains_code(line, &settings.task_tags[..]) {
-            let mut diagnostic = Diagnostic::new(CommentedOutCode, range);
+            let mut diagnostic = Diagnostic::new(CommentedOutCode, *range);
            diagnostic.set_fix(Fix::display_only_edit(Edit::range_deletion(
-                locator.full_lines_range(range),
+                locator.full_lines_range(*range),
            )));
            diagnostics.push(diagnostic);
        }
    }
 }

-/// Parses the rest of a [PEP 723](https://peps.python.org/pep-0723/)
-/// script comment and moves `comments` past the script comment's end unless
-/// the script comment is invalid.
-///
-/// Returns `true` if it is a valid script comment.
-fn skip_script_comments<I>(
-    script_start: TextRange,
-    comments: &mut std::iter::Peekable<I>,
-    locator: &Locator,
-) -> bool
-where
-    I: Iterator<Item = TextRange>,
-{
-    let line_end = locator.full_line_end(script_start.end());
-    let rest = locator.after(line_end);
-    let mut end_offset = None;
-    let mut lines = UniversalNewlineIterator::with_offset(rest, line_end).peekable();
-
-    while let Some(line) = lines.next() {
-        let Some(content) = script_line_content(&line) else {
-            break;
-        };
-
-        if content == "///" {
-            // > Precedence for an ending line # /// is given when the next line is not a valid
-            // > embedded content line as described above.
-            // > For example, the following is a single fully valid block:
-            // > ```python
-            // > # /// some-toml
-            // > # embedded-csharp = """
-            // > # /// <summary>
-            // > # /// text
-            // > # ///
-            // > # /// </summary>
-            // > # public class MyClass { }
-            // > # """
-            // > # ///
-            // ````
-            if lines.next().is_some_and(|line| is_valid_script_line(&line)) {
-                continue;
-            }
-            end_offset = Some(line.full_end());
-            break;
-        }
-    }
-
-    // > Unclosed blocks MUST be ignored.
-    let Some(end_offset) = end_offset else {
-        return false;
-    };
-
-    // Skip over all script-comments.
-    while let Some(comment) = comments.peek() {
-        if comment.start() >= end_offset {
-            break;
-        }
-
-        comments.next();
-    }
-
-    true
-}
-
-fn script_line_content(line: &str) -> Option<&str> {
-    let Some(rest) = line.strip_prefix('#') else {
-        // Not a comment
-        return None;
-    };
-
-    // An empty line
-    if rest.is_empty() {
-        return Some("");
-    }
-
-    // > If there are characters after the # then the first character MUST be a space.
-    rest.strip_prefix(' ')
-}
-
-fn is_valid_script_line(line: &str) -> bool {
-    script_line_content(line).is_some()
-}
-
 /// Returns `true` if line contains an own-line comment.
 fn is_own_line_comment(line: &str) -> bool {
    for char in line.chars() {
@@ -174,77 +104,9 @@ fn is_script_tag_start(line: &str) -> bool {
    line == "# /// script"
 }

-#[cfg(test)]
-mod tests {
-    use crate::rules::eradicate::rules::commented_out_code::skip_script_comments;
-    use ruff_python_parser::parse_module;
-    use ruff_python_trivia::CommentRanges;
-    use ruff_source_file::Locator;
-    use ruff_text_size::TextSize;
-    #[test]
-    fn script_comment() {
-        let code = r#"
-# /// script
-# requires-python = ">=3.11"
-# dependencies = [
-#   "requests<3",
-#   "rich",
-# ]
-# ///
-
-a = 10 # abc
-        "#;
-
-        let parsed = parse_module(code).unwrap();
-        let locator = Locator::new(code);
-
-        let comments = CommentRanges::from(parsed.tokens());
-        let mut comments = comments.into_iter().peekable();
-
-        let script_start = code.find("# /// script").unwrap();
-        let script_start_range = locator.full_line_range(TextSize::try_from(script_start).unwrap());
-
-        let valid = skip_script_comments(script_start_range, &mut comments, &Locator::new(code));
-
-        assert!(valid);
-
-        let next_comment = comments.next();
-
-        assert!(next_comment.is_some());
-        assert_eq!(&code[next_comment.unwrap()], "# abc");
-    }
-
-    #[test]
-    fn script_comment_end_precedence() {
-        let code = r#"
-# /// script
-# [tool.uv]
-# extra-index-url = ["https://pypi.org/simple", """\
-# https://example.com/
-# ///
-# """
-# ]
-# ///
-
-a = 10 # abc
-        "#;
-
-        let parsed = parse_module(code).unwrap();
-        let locator = Locator::new(code);
-
-        let comments = CommentRanges::from(parsed.tokens());
-        let mut comments = comments.into_iter().peekable();
-
-        let script_start = code.find("# /// script").unwrap();
-        let script_start_range = locator.full_line_range(TextSize::try_from(script_start).unwrap());
-
-        let valid = skip_script_comments(script_start_range, &mut comments, &Locator::new(code));
-
-        assert!(valid);
-
-        let next_comment = comments.next();
-
-        assert!(next_comment.is_some());
-        assert_eq!(&code[next_comment.unwrap()], "# abc");
-    }
+/// Returns `true` if the line appears to start a script tag.
+///
+/// See: <https://peps.python.org/pep-0723/>
+fn is_script_tag_end(line: &str) -> bool {
+    line == "# ///"
 }
--- a/crates/ruff_linter/src/rules/eradicate/snapshots/ruff_linterruleseradicatetestsERA001_ERA001.py.snap
+++ b/crates/ruff_linter/src/rules/eradicate/snapshots/ruff_linterruleseradicatetestsERA001_ERA001.py.snap
@@ -321,38 +321,3 @@ ERA001.py:47:1: ERA001 Found commented-out code
 48 47 | # ///
 49 48 | 
 50 49 | # Script tag (OK)
-
-ERA001.py:75:1: ERA001 Found commented-out code
-   |
-73 | # /// script
-74 | # requires-python = ">=3.11"
-75 | # dependencies = [
-   | ^^^^^^^^^^^^^^^^^^ ERA001
-76 | #   "requests<3",
-77 | #   "rich",
-   |
-   = help: Remove commented-out code
-
-ℹ Display-only fix
-72 72 | 
-73 73 | # /// script
-74 74 | # requires-python = ">=3.11"
-75    |-# dependencies = [
-76 75 | #   "requests<3",
-77 76 | #   "rich",
-78 77 | # ]
-
-ERA001.py:78:1: ERA001 Found commented-out code
-   |
-76 | #   "requests<3",
-77 | #   "rich",
-78 | # ]
-   | ^^^ ERA001
-   |
-   = help: Remove commented-out code
-
-ℹ Display-only fix
-75 75 | # dependencies = [
-76 76 | #   "requests<3",
-77 77 | #   "rich",
-78    |-# ]
--- a/crates/ruff_linter/src/rules/flake8_executable/rules/mod.rs
+++ b/crates/ruff_linter/src/rules/flake8_executable/rules/mod.rs
@@ -1,8 +1,5 @@
 use std::path::Path;

-use crate::codes::Rule;
-use crate::comments::shebang::ShebangDirective;
-use crate::settings::LinterSettings;
 use ruff_diagnostics::Diagnostic;
 use ruff_python_trivia::CommentRanges;
 use ruff_source_file::Locator;
@@ -12,6 +9,8 @@ pub(crate) use shebang_missing_python::*;
 pub(crate) use shebang_not_executable::*;
 pub(crate) use shebang_not_first_line::*;

+use crate::comments::shebang::ShebangDirective;
+
 mod shebang_leading_whitespace;
 mod shebang_missing_executable_file;
 mod shebang_missing_python;
@@ -23,39 +22,34 @@ pub(crate) fn from_tokens(
    path: &Path,
    locator: &Locator,
    comment_ranges: &CommentRanges,
-    settings: &LinterSettings,
 ) {
    let mut has_any_shebang = false;
    for range in comment_ranges {
-        let comment = locator.slice(range);
+        let comment = locator.slice(*range);
        if let Some(shebang) = ShebangDirective::try_extract(comment) {
            has_any_shebang = true;

-            if let Some(diagnostic) = shebang_missing_python(range, &shebang) {
+            if let Some(diagnostic) = shebang_missing_python(*range, &shebang) {
                diagnostics.push(diagnostic);
            }

-            if settings.rules.enabled(Rule::ShebangNotExecutable) {
-                if let Some(diagnostic) = shebang_not_executable(path, range) {
-                    diagnostics.push(diagnostic);
-                }
-            }
-
-            if let Some(diagnostic) = shebang_leading_whitespace(range, locator) {
+            if let Some(diagnostic) = shebang_not_executable(path, *range) {
                diagnostics.push(diagnostic);
            }

-            if let Some(diagnostic) = shebang_not_first_line(range, locator) {
+            if let Some(diagnostic) = shebang_leading_whitespace(*range, locator) {
+                diagnostics.push(diagnostic);
+            }
+
+            if let Some(diagnostic) = shebang_not_first_line(*range, locator) {
                diagnostics.push(diagnostic);
            }
        }
    }

    if !has_any_shebang {
-        if settings.rules.enabled(Rule::ShebangMissingExecutableFile) {
-            if let Some(diagnostic) = shebang_missing_executable_file(path) {
-                diagnostics.push(diagnostic);
-            }
+        if let Some(diagnostic) = shebang_missing_executable_file(path) {
+            diagnostics.push(diagnostic);
        }
    }
 }
--- a/crates/ruff_linter/src/rules/flake8_pyi/rules/type_comment_in_stub.rs
+++ b/crates/ruff_linter/src/rules/flake8_pyi/rules/type_comment_in_stub.rs
@@ -41,10 +41,10 @@ pub(crate) fn type_comment_in_stub(
    comment_ranges: &CommentRanges,
 ) {
    for range in comment_ranges {
-        let comment = locator.slice(range);
+        let comment = locator.slice(*range);

        if TYPE_COMMENT_REGEX.is_match(comment) && !TYPE_IGNORE_REGEX.is_match(comment) {
-            diagnostics.push(Diagnostic::new(TypeCommentInStub, range));
+            diagnostics.push(Diagnostic::new(TypeCommentInStub, *range));
        }
    }
 }
--- a/crates/ruff_linter/src/rules/isort/rules/add_required_imports.rs
+++ b/crates/ruff_linter/src/rules/isort/rules/add_required_imports.rs
@@ -35,9 +35,6 @@ use crate::settings::LinterSettings;
 ///
 /// import typing
 /// ```
-///
-/// ## Options
-/// - `lint.isort.required-imports`
 #[violation]
 pub struct MissingRequiredImport(pub String);

--- a/crates/ruff_linter/src/rules/pydoclint/rules/check_docstring.rs
+++ b/crates/ruff_linter/src/rules/pydoclint/rules/check_docstring.rs
@@ -741,10 +741,6 @@ fn returns_documented(
        || (matches!(convention, Some(Convention::Google)) && starts_with_returns(docstring))
 }

-fn should_document_returns(function_def: &ast::StmtFunctionDef) -> bool {
-    !matches!(function_def.name.as_str(), "__new__")
-}
-
 fn starts_with_yields(docstring: &Docstring) -> bool {
    if let Some(first_word) = docstring.body().as_str().split(' ').next() {
        return matches!(first_word, "Yield" | "Yields");
@@ -872,9 +868,7 @@ pub(crate) fn check_docstring(

    // DOC201
    if checker.enabled(Rule::DocstringMissingReturns) {
-        if should_document_returns(function_def)
-            && !returns_documented(docstring, &docstring_sections, convention)
-        {
+        if !returns_documented(docstring, &docstring_sections, convention) {
            let extra_property_decorators = checker.settings.pydocstyle.property_decorators();
            if !definition.is_property(extra_property_decorators, semantic) {
                if let Some(body_return) = body_entries.returns.first() {
--- a/crates/ruff_linter/src/rules/pydocstyle/rules/triple_quotes.rs
+++ b/crates/ruff_linter/src/rules/pydocstyle/rules/triple_quotes.rs
@@ -67,7 +67,9 @@ impl Violation for TripleSingleQuotes {
 pub(crate) fn triple_quotes(checker: &mut Checker, docstring: &Docstring) {
    let leading_quote = docstring.leading_quote();

-    let prefixes = leading_quote.trim_end_matches(['\'', '"']).to_owned();
+    let prefixes = leading_quote
+        .trim_end_matches(|c| c == '\'' || c == '"')
+        .to_owned();

    let expected_quote = if docstring.body().contains("\"\"\"") {
        if docstring.body().contains("\'\'\'") {
--- a/crates/ruff_linter/src/rules/pyflakes/mod.rs
+++ b/crates/ruff_linter/src/rules/pyflakes/mod.rs
@@ -208,18 +208,6 @@ mod tests {
        Ok(())
    }

-    #[test]
-    fn f821_with_builtin_added_on_new_py_version_but_old_target_version_specified() {
-        let diagnostics = test_snippet(
-            "PythonFinalizationError",
-            &LinterSettings {
-                target_version: crate::settings::types::PythonVersion::Py312,
-                ..LinterSettings::for_rule(Rule::UndefinedName)
-            },
-        );
-        assert_messages!(diagnostics);
-    }
-
    #[test_case(Rule::UnusedVariable, Path::new("F841_4.py"))]
    #[test_case(Rule::UnusedImport, Path::new("__init__.py"))]
    #[test_case(Rule::UnusedImport, Path::new("F401_24/__init__.py"))]
--- a/crates/ruff_linter/src/rules/pyflakes/rules/undefined_name.rs
+++ b/crates/ruff_linter/src/rules/pyflakes/rules/undefined_name.rs
@@ -19,35 +19,17 @@ use ruff_macros::{derive_message_formats, violation};
 ///     return n * 2
 /// ```
 ///
-/// ## Options
-/// - [`target-version`]: Can be used to configure which symbols Ruff will understand
-///   as being available in the `builtins` namespace.
-///
 /// ## References
 /// - [Python documentation: Naming and binding](https://docs.python.org/3/reference/executionmodel.html#naming-and-binding)
 #[violation]
 pub struct UndefinedName {
    pub(crate) name: String,
-    pub(crate) minor_version_builtin_added: Option<u8>,
 }

 impl Violation for UndefinedName {
    #[derive_message_formats]
    fn message(&self) -> String {
-        let UndefinedName {
-            name,
-            minor_version_builtin_added,
-        } = self;
-        let tip = minor_version_builtin_added.map(|version_added| {
-            format!(
-                r#"Consider specifying `requires-python = ">= 3.{version_added}"` or `tool.ruff.target-version = "py3{version_added}"` in your `pyproject.toml` file."#
-            )
-        });
-
-        if let Some(tip) = tip {
-            format!("Undefined name `{name}`. {tip}")
-        } else {
-            format!("Undefined name `{name}`")
-        }
+        let UndefinedName { name } = self;
+        format!("Undefined name `{name}`")
    }
 }
--- a/crates/ruff_linter/src/rules/pyflakes/snapshots/ruff_linterrulespyflakestestsf821_with_builtin_added_on_new_py_version_but_old_target_version_specified.snap
+++ b/crates/ruff_linter/src/rules/pyflakes/snapshots/ruff_linterrulespyflakestestsf821_with_builtin_added_on_new_py_version_but_old_target_version_specified.snap
@@ -1,8 +0,0 @@
---
-source: crates/ruff_linter/src/rules/pyflakes/mod.rs
---
-<filename>:1:1: F821 Undefined name `PythonFinalizationError`. Consider specifying `requires-python = ">= 3.13"` or `tool.ruff.target-version = "py313"` in your `pyproject.toml` file.
-  |
-1 | PythonFinalizationError
-  | ^^^^^^^^^^^^^^^^^^^^^^^ F821
-  |
--- a/crates/ruff_linter/src/rules/pygrep_hooks/rules/blanket_type_ignore.rs
+++ b/crates/ruff_linter/src/rules/pygrep_hooks/rules/blanket_type_ignore.rs
@@ -55,7 +55,7 @@ pub(crate) fn blanket_type_ignore(
    locator: &Locator,
 ) {
    for range in comment_ranges {
-        let line = locator.slice(range);
+        let line = locator.slice(*range);

        // Match, e.g., `# type: ignore` or `# type: ignore[attr-defined]`.
        // See: https://github.com/python/mypy/blob/b43e0d34247a6d1b3b9d9094d184bbfcb9808bb9/mypy/fastparse.py#L248
--- a/crates/ruff_linter/src/rules/pylint/rules/bad_dunder_method_name.rs
+++ b/crates/ruff_linter/src/rules/pylint/rules/bad_dunder_method_name.rs
@@ -8,10 +8,10 @@ use crate::checkers::ast::Checker;
 use crate::rules::pylint::helpers::is_known_dunder_method;

 /// ## What it does
-/// Checks for dunder methods that have no special meaning in Python 3.
+/// Checks for misspelled and unknown dunder names in method definitions.
 ///
 /// ## Why is this bad?
-/// Misspelled or no longer supported dunder name methods may cause your code to not function
+/// Misspelled dunder name methods may cause your code to not function
 /// as expected.
 ///
 /// Since dunder methods are associated with customizing the behavior
@@ -51,7 +51,7 @@ impl Violation for BadDunderMethodName {
    #[derive_message_formats]
    fn message(&self) -> String {
        let BadDunderMethodName { name } = self;
-        format!("Dunder method `{name}` has no special meaning in Python 3")
+        format!("Bad or misspelled dunder method name `{name}`")
    }
 }

--- a/crates/ruff_linter/src/rules/pylint/rules/empty_comment.rs
+++ b/crates/ruff_linter/src/rules/pylint/rules/empty_comment.rs
@@ -56,7 +56,7 @@ pub(crate) fn empty_comments(
        }

        // If the line contains an empty comment, add a diagnostic.
-        if let Some(diagnostic) = empty_comment(range, locator) {
+        if let Some(diagnostic) = empty_comment(*range, locator) {
            diagnostics.push(diagnostic);
        }
    }
--- a/crates/ruff_linter/src/rules/pylint/snapshots/ruff_linterrulespylinttestsPLW3201_bad_dunder_method_name.py.snap
+++ b/crates/ruff_linter/src/rules/pylint/snapshots/ruff_linterrulespylinttestsPLW3201_bad_dunder_method_name.py.snap
@@ -1,7 +1,7 @@
 ---
 source: crates/ruff_linter/src/rules/pylint/mod.rs
 ---
-bad_dunder_method_name.py:5:9: PLW3201 Dunder method `_init_` has no special meaning in Python 3
+bad_dunder_method_name.py:5:9: PLW3201 Bad or misspelled dunder method name `_init_`
  |
 4 | class Apples:
 5 |     def _init_(self):  # [bad-dunder-name]
@@ -9,7 +9,7 @@ bad_dunder_method_name.py:5:9: PLW3201 Dunder method `_init_` has no special mea
 6 |         pass
  |

-bad_dunder_method_name.py:8:9: PLW3201 Dunder method `__hello__` has no special meaning in Python 3
+bad_dunder_method_name.py:8:9: PLW3201 Bad or misspelled dunder method name `__hello__`
  |
 6 |         pass
 7 | 
@@ -18,7 +18,7 @@ bad_dunder_method_name.py:8:9: PLW3201 Dunder method `__hello__` has no special
 9 |         print("hello")
  |

-bad_dunder_method_name.py:11:9: PLW3201 Dunder method `__init_` has no special meaning in Python 3
+bad_dunder_method_name.py:11:9: PLW3201 Bad or misspelled dunder method name `__init_`
   |
 9 |         print("hello")
 10 | 
@@ -28,7 +28,7 @@ bad_dunder_method_name.py:11:9: PLW3201 Dunder method `__init_` has no special m
 13 |         pass
   |

-bad_dunder_method_name.py:15:9: PLW3201 Dunder method `_init_` has no special meaning in Python 3
+bad_dunder_method_name.py:15:9: PLW3201 Bad or misspelled dunder method name `_init_`
   |
 13 |         pass
 14 | 
@@ -38,7 +38,7 @@ bad_dunder_method_name.py:15:9: PLW3201 Dunder method `_init_` has no special me
 17 |         pass
   |

-bad_dunder_method_name.py:19:9: PLW3201 Dunder method `___neg__` has no special meaning in Python 3
+bad_dunder_method_name.py:19:9: PLW3201 Bad or misspelled dunder method name `___neg__`
   |
 17 |         pass
 18 | 
@@ -48,7 +48,7 @@ bad_dunder_method_name.py:19:9: PLW3201 Dunder method `___neg__` has no special
 21 |         pass
   |

-bad_dunder_method_name.py:23:9: PLW3201 Dunder method `__inv__` has no special meaning in Python 3
+bad_dunder_method_name.py:23:9: PLW3201 Bad or misspelled dunder method name `__inv__`
   |
 21 |         pass
 22 | 
@@ -58,10 +58,4 @@ bad_dunder_method_name.py:23:9: PLW3201 Dunder method `__inv__` has no special m
 25 |         pass
   |

-bad_dunder_method_name.py:98:9: PLW3201 Dunder method `__unicode__` has no special meaning in Python 3
-   |
-97 |     # Removed with Python 3
-98 |     def __unicode__(self):
-   |         ^^^^^^^^^^^ PLW3201
-99 |         pass
-   |
+
--- a/crates/ruff_linter/src/rules/pyupgrade/rules/deprecated_unittest_alias.rs
+++ b/crates/ruff_linter/src/rules/pyupgrade/rules/deprecated_unittest_alias.rs
@@ -13,7 +13,7 @@ use crate::checkers::ast::Checker;
 ///
 /// ## Why is this bad?
 /// The `unittest` module has deprecated aliases for some of its methods.
-/// The deprecated aliases were removed in Python 3.12. Instead of aliases,
+/// The aliases may be removed in future versions of Python. Instead,
 /// use their non-deprecated counterparts.
 ///
 /// ## Example
@@ -37,7 +37,7 @@ use crate::checkers::ast::Checker;
 /// ```
 ///
 /// ## References
-/// - [Python 3.11 documentation: Deprecated aliases](https://docs.python.org/3.11/library/unittest.html#deprecated-aliases)
+/// - [Python documentation: Deprecated aliases](https://docs.python.org/3/library/unittest.html#deprecated-aliases)
 #[violation]
 pub struct DeprecatedUnittestAlias {
    alias: String,
--- a/crates/ruff_linter/src/rules/refurb/mod.rs
+++ b/crates/ruff_linter/src/rules/refurb/mod.rs
@@ -46,7 +46,6 @@ mod tests {
    #[test_case(Rule::WriteWholeFile, Path::new("FURB103.py"))]
    #[test_case(Rule::FStringNumberFormat, Path::new("FURB116.py"))]
    #[test_case(Rule::SortedMinMax, Path::new("FURB192.py"))]
-    #[test_case(Rule::SliceToRemovePrefixOrSuffix, Path::new("FURB188.py"))]
    fn rules(rule_code: Rule, path: &Path) -> Result<()> {
        let snapshot = format!("{}_{}", rule_code.noqa_code(), path.to_string_lossy());
        let diagnostics = test_path(
--- a/crates/ruff_linter/src/rules/refurb/rules/mod.rs
+++ b/crates/ruff_linter/src/rules/refurb/rules/mod.rs
@@ -23,7 +23,6 @@ pub(crate) use repeated_append::*;
 pub(crate) use repeated_global::*;
 pub(crate) use single_item_membership_test::*;
 pub(crate) use slice_copy::*;
-pub(crate) use slice_to_remove_prefix_or_suffix::*;
 pub(crate) use sorted_min_max::*;
 pub(crate) use type_none_comparison::*;
 pub(crate) use unnecessary_enumerate::*;
@@ -56,7 +55,6 @@ mod repeated_append;
 mod repeated_global;
 mod single_item_membership_test;
 mod slice_copy;
-mod slice_to_remove_prefix_or_suffix;
 mod sorted_min_max;
 mod type_none_comparison;
 mod unnecessary_enumerate;
--- a/crates/ruff_linter/src/rules/refurb/rules/slice_to_remove_prefix_or_suffix.rs
+++ b/crates/ruff_linter/src/rules/refurb/rules/slice_to_remove_prefix_or_suffix.rs
@@ -1,474 +0,0 @@
-use crate::{checkers::ast::Checker, settings::types::PythonVersion};
-use ruff_diagnostics::{AlwaysFixableViolation, Diagnostic, Edit, Fix};
-use ruff_macros::{derive_message_formats, violation};
-use ruff_python_ast as ast;
-use ruff_python_semantic::SemanticModel;
-use ruff_source_file::Locator;
-use ruff_text_size::{Ranged, TextLen};
-
-/// ## What it does
-/// Checks for the removal of a prefix or suffix from a string by assigning
-/// the string to a slice after checking `.startswith()` or `.endswith()`, respectively.
-///
-/// ## Why is this bad?
-/// The methods [`str.removeprefix`] and [`str.removesuffix`],
-/// introduced in Python 3.9, have the same behavior
-/// and are more readable and efficient.
-///
-/// ## Example
-/// ```python
-/// filename[:-4] if filename.endswith(".txt") else filename
-/// ```
-///
-/// ```python
-/// if text.startswith("pre"):
-///     text = text[3:]
-/// ```
-///
-/// Use instead:
-/// ```python
-/// filename = filename.removesuffix(".txt")
-/// ```
-///
-/// ```python
-/// text = text.removeprefix("pre")
-/// ```
-///
-/// [`str.removeprefix`]: https://docs.python.org/3/library/stdtypes.html#str.removeprefix
-/// [`str.removesuffix`]: https://docs.python.org/3/library/stdtypes.html#str.removesuffix
-#[violation]
-pub struct SliceToRemovePrefixOrSuffix {
-    string: String,
-    affix_kind: AffixKind,
-    stmt_or_expression: StmtOrExpr,
-}
-
-impl AlwaysFixableViolation for SliceToRemovePrefixOrSuffix {
-    #[derive_message_formats]
-    fn message(&self) -> String {
-        match self.affix_kind {
-            AffixKind::StartsWith => {
-                format!("Prefer `removeprefix` over conditionally replacing with slice.")
-            }
-            AffixKind::EndsWith => {
-                format!("Prefer `removesuffix` over conditionally replacing with slice.")
-            }
-        }
-    }
-
-    fn fix_title(&self) -> String {
-        let method_name = self.affix_kind.as_str();
-        let replacement = self.affix_kind.replacement();
-        let context = match self.stmt_or_expression {
-            StmtOrExpr::Statement => "assignment",
-            StmtOrExpr::Expression => "ternary expression",
-        };
-        format!("Use {replacement} instead of {context} conditional upon {method_name}.")
-    }
-}
-
-/// FURB188
-pub(crate) fn slice_to_remove_affix_expr(checker: &mut Checker, if_expr: &ast::ExprIf) {
-    if checker.settings.target_version < PythonVersion::Py39 {
-        return;
-    }
-
-    if let Some(removal_data) = affix_removal_data_expr(if_expr) {
-        if affix_matches_slice_bound(&removal_data, checker.semantic()) {
-            let kind = removal_data.affix_query.kind;
-            let text = removal_data.text;
-
-            let mut diagnostic = Diagnostic::new(
-                SliceToRemovePrefixOrSuffix {
-                    affix_kind: kind,
-                    string: checker.locator().slice(text).to_string(),
-                    stmt_or_expression: StmtOrExpr::Expression,
-                },
-                if_expr.range,
-            );
-            let replacement =
-                generate_removeaffix_expr(text, &removal_data.affix_query, checker.locator());
-
-            diagnostic.set_fix(Fix::safe_edit(Edit::replacement(
-                replacement,
-                if_expr.start(),
-                if_expr.end(),
-            )));
-            checker.diagnostics.push(diagnostic);
-        }
-    }
-}
-
-/// FURB188
-pub(crate) fn slice_to_remove_affix_stmt(checker: &mut Checker, if_stmt: &ast::StmtIf) {
-    if checker.settings.target_version < PythonVersion::Py39 {
-        return;
-    }
-    if let Some(removal_data) = affix_removal_data_stmt(if_stmt) {
-        if affix_matches_slice_bound(&removal_data, checker.semantic()) {
-            let kind = removal_data.affix_query.kind;
-            let text = removal_data.text;
-
-            let mut diagnostic = Diagnostic::new(
-                SliceToRemovePrefixOrSuffix {
-                    affix_kind: kind,
-                    string: checker.locator().slice(text).to_string(),
-                    stmt_or_expression: StmtOrExpr::Statement,
-                },
-                if_stmt.range,
-            );
-
-            let replacement = generate_assignment_with_removeaffix(
-                text,
-                &removal_data.affix_query,
-                checker.locator(),
-            );
-
-            diagnostic.set_fix(Fix::safe_edit(Edit::replacement(
-                replacement,
-                if_stmt.start(),
-                if_stmt.end(),
-            )));
-            checker.diagnostics.push(diagnostic);
-        }
-    }
-}
-
-/// Given an expression of the form:
-///
-/// ```python
-/// text[slice] if text.func(affix) else text
-/// ```
-///
-/// where `func` is either `startswith` or `endswith`,
-/// this function collects `text`,`func`, `affix`, and the non-null
-/// bound of the slice. Otherwise, returns `None`.
-fn affix_removal_data_expr(if_expr: &ast::ExprIf) -> Option<RemoveAffixData> {
-    let ast::ExprIf {
-        test,
-        body,
-        orelse,
-        range: _,
-    } = if_expr;
-
-    let ast::ExprSubscript { value, slice, .. } = body.as_subscript_expr()?;
-    // Variable names correspond to:
-    // ```python
-    // value[slice] if test else orelse
-    // ```
-    affix_removal_data(value, test, orelse, slice)
-}
-
-/// Given a statement of the form:
-///
-/// ```python
-///  if text.func(affix):
-///     text = text[slice]
-/// ```
-///
-/// where `func` is either `startswith` or `endswith`,
-/// this function collects `text`,`func`, `affix`, and the non-null
-/// bound of the slice. Otherwise, returns `None`.
-fn affix_removal_data_stmt(if_stmt: &ast::StmtIf) -> Option<RemoveAffixData> {
-    let ast::StmtIf {
-        test,
-        body,
-        elif_else_clauses,
-        range: _,
-    } = if_stmt;
-
-    // Cannot safely transform, e.g.,
-    // ```python
-    // if text.startswith(prefix):
-    //     text = text[len(prefix):]
-    // else:
-    //     text = "something completely different"
-    // ```
-    if !elif_else_clauses.is_empty() {
-        return None;
-    };
-
-    // Cannot safely transform, e.g.,
-    // ```python
-    // if text.startswith(prefix):
-    //     text = f"{prefix} something completely different"
-    //     text = text[len(prefix):]
-    // ```
-    let [statement] = body.as_slice() else {
-        return None;
-    };
-
-    // Variable names correspond to:
-    // ```python
-    // if test:
-    //     else_or_target_name = value[slice]
-    // ```
-    let ast::StmtAssign {
-        value,
-        targets,
-        range: _,
-    } = statement.as_assign_stmt()?;
-    let [target] = targets.as_slice() else {
-        return None;
-    };
-    let ast::ExprSubscript { value, slice, .. } = value.as_subscript_expr()?;
-
-    affix_removal_data(value, test, target, slice)
-}
-
-/// Suppose given a statement of the form:
-/// ```python
-/// if test:
-///     else_or_target_name = value[slice]
-/// ```
-/// or an expression of the form:
-/// ```python
-/// value[slice] if test else else_or_target_name
-/// ```
-/// This function verifies that
-///   - `value` and `else_or_target_name`
-///     are equal to a common name `text`
-///   - `test` is of the form `text.startswith(prefix)`
-///     or `text.endswith(suffix)`
-///   - `slice` has no upper bound in the case of a prefix,
-///     and no lower bound in the case of a suffix
-///
-/// If these conditions are satisfied, the function
-/// returns the corresponding `RemoveAffixData` object;
-/// otherwise it returns `None`.
-fn affix_removal_data<'a>(
-    value: &'a ast::Expr,
-    test: &'a ast::Expr,
-    else_or_target: &'a ast::Expr,
-    slice: &'a ast::Expr,
-) -> Option<RemoveAffixData<'a>> {
-    let compr_value = ast::comparable::ComparableExpr::from(value);
-    let compr_else_or_target = ast::comparable::ComparableExpr::from(else_or_target);
-    if compr_value != compr_else_or_target {
-        return None;
-    }
-    let slice = slice.as_slice_expr()?;
-    let compr_test_expr = ast::comparable::ComparableExpr::from(
-        &test.as_call_expr()?.func.as_attribute_expr()?.value,
-    );
-    let func_name = test
-        .as_call_expr()?
-        .func
-        .as_attribute_expr()?
-        .attr
-        .id
-        .as_str();
-
-    let func_args = &test.as_call_expr()?.arguments.args;
-
-    let [affix] = func_args.as_ref() else {
-        return None;
-    };
-    if compr_value != compr_test_expr || compr_test_expr != compr_else_or_target {
-        return None;
-    }
-    let (affix_kind, bound) = match func_name {
-        "startswith" if slice.upper.is_none() => (AffixKind::StartsWith, slice.lower.as_ref()?),
-        "endswith" if slice.lower.is_none() => (AffixKind::EndsWith, slice.upper.as_ref()?),
-        _ => return None,
-    };
-    Some(RemoveAffixData {
-        text: value,
-        bound,
-        affix_query: AffixQuery {
-            kind: affix_kind,
-            affix,
-        },
-    })
-}
-
-/// Tests whether the slice of the given string actually removes the
-/// detected affix.
-///
-/// For example, in the situation
-///
-/// ```python
-///  text[:bound] if text.endswith(suffix) else text
-/// ```
-///
-/// This function verifies that `bound == -len(suffix)` in two cases:
-///   - `suffix` is a string literal and `bound` is a number literal
-///   - `suffix` is an expression and `bound` is
-///     exactly `-len(suffix)` (as AST nodes, prior to evaluation.)
-fn affix_matches_slice_bound(data: &RemoveAffixData, semantic: &SemanticModel) -> bool {
-    let RemoveAffixData {
-        text: _,
-        bound,
-        affix_query: AffixQuery { kind, affix },
-    } = *data;
-
-    match (kind, bound, affix) {
-        (
-            AffixKind::StartsWith,
-            ast::Expr::NumberLiteral(ast::ExprNumberLiteral {
-                value: num,
-                range: _,
-            }),
-            ast::Expr::StringLiteral(ast::ExprStringLiteral {
-                range: _,
-                value: string_val,
-            }),
-        ) => num
-            .as_int()
-            .and_then(ast::Int::as_u32) // Only support prefix removal for size at most `u32::MAX`
-            .is_some_and(|x| x == string_val.to_str().text_len().to_u32()),
-        (
-            AffixKind::StartsWith,
-            ast::Expr::Call(ast::ExprCall {
-                range: _,
-                func,
-                arguments,
-            }),
-            _,
-        ) => {
-            arguments.len() == 1
-                && arguments.find_positional(0).is_some_and(|arg| {
-                    let compr_affix = ast::comparable::ComparableExpr::from(affix);
-                    let compr_arg = ast::comparable::ComparableExpr::from(arg);
-                    compr_affix == compr_arg
-                })
-                && semantic.match_builtin_expr(func, "len")
-        }
-        (
-            AffixKind::EndsWith,
-            ast::Expr::UnaryOp(ast::ExprUnaryOp {
-                op: ast::UnaryOp::USub,
-                operand,
-                range: _,
-            }),
-            ast::Expr::StringLiteral(ast::ExprStringLiteral {
-                range: _,
-                value: string_val,
-            }),
-        ) => operand.as_number_literal_expr().is_some_and(
-            |ast::ExprNumberLiteral { value, .. }| {
-                // Only support prefix removal for size at most `u32::MAX`
-                value
-                    .as_int()
-                    .and_then(ast::Int::as_u32)
-                    .is_some_and(|x| x == string_val.to_str().text_len().to_u32())
-            },
-        ),
-        (
-            AffixKind::EndsWith,
-            ast::Expr::UnaryOp(ast::ExprUnaryOp {
-                op: ast::UnaryOp::USub,
-                operand,
-                range: _,
-            }),
-            _,
-        ) => operand.as_call_expr().is_some_and(
-            |ast::ExprCall {
-                 range: _,
-                 func,
-                 arguments,
-             }| {
-                arguments.len() == 1
-                    && arguments.find_positional(0).is_some_and(|arg| {
-                        let compr_affix = ast::comparable::ComparableExpr::from(affix);
-                        let compr_arg = ast::comparable::ComparableExpr::from(arg);
-                        compr_affix == compr_arg
-                    })
-                    && semantic.match_builtin_expr(func, "len")
-            },
-        ),
-        _ => false,
-    }
-}
-
-/// Generates the source code string
-/// ```python
-/// text = text.removeprefix(prefix)
-/// ```
-/// or
-/// ```python
-/// text = text.removesuffix(prefix)
-/// ```
-/// as appropriate.
-fn generate_assignment_with_removeaffix(
-    text: &ast::Expr,
-    affix_query: &AffixQuery,
-    locator: &Locator,
-) -> String {
-    let text_str = locator.slice(text);
-    let affix_str = locator.slice(affix_query.affix);
-    let replacement = affix_query.kind.replacement();
-    format!("{text_str} = {text_str}.{replacement}({affix_str})")
-}
-
-/// Generates the source code string
-/// ```python
-/// text.removeprefix(prefix)
-/// ```
-/// or
-///
-/// ```python
-/// text.removesuffix(suffix)
-/// ```
-/// as appropriate.
-fn generate_removeaffix_expr(
-    text: &ast::Expr,
-    affix_query: &AffixQuery,
-    locator: &Locator,
-) -> String {
-    let text_str = locator.slice(text);
-    let affix_str = locator.slice(affix_query.affix);
-    let replacement = affix_query.kind.replacement();
-    format!("{text_str}.{replacement}({affix_str})")
-}
-
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
-enum StmtOrExpr {
-    Statement,
-    Expression,
-}
-
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
-enum AffixKind {
-    StartsWith,
-    EndsWith,
-}
-
-impl AffixKind {
-    const fn as_str(self) -> &'static str {
-        match self {
-            Self::StartsWith => "startswith",
-            Self::EndsWith => "endswith",
-        }
-    }
-
-    const fn replacement(self) -> &'static str {
-        match self {
-            Self::StartsWith => "removeprefix",
-            Self::EndsWith => "removesuffix",
-        }
-    }
-}
-
-/// Components of `startswith(prefix)` or `endswith(suffix)`.
-#[derive(Debug)]
-struct AffixQuery<'a> {
-    /// Whether the method called is `startswith` or `endswith`.
-    kind: AffixKind,
-    /// Node representing the prefix or suffix being passed to the string method.
-    affix: &'a ast::Expr,
-}
-
-/// Ingredients for a statement or expression
-/// which potentially removes a prefix or suffix from a string.
-///
-/// Specifically
-#[derive(Debug)]
-struct RemoveAffixData<'a> {
-    /// Node representing the string whose prefix or suffix we want to remove
-    text: &'a ast::Expr,
-    /// Node representing the bound used to slice the string
-    bound: &'a ast::Expr,
-    /// Contains the prefix or suffix used in `text.startswith(prefix)` or `text.endswith(suffix)`
-    affix_query: AffixQuery<'a>,
-}
--- a/crates/ruff_linter/src/rules/refurb/snapshots/ruff_linterrulesrefurbtestsFURB188_FURB188.py.snap
+++ b/crates/ruff_linter/src/rules/refurb/snapshots/ruff_linterrulesrefurbtestsFURB188_FURB188.py.snap
@@ -1,177 +0,0 @@
---
-source: crates/ruff_linter/src/rules/refurb/mod.rs
---
-FURB188.py:7:5: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
-   |
- 6 |   def remove_extension_via_slice(filename: str) -> str:
- 7 |       if filename.endswith(".txt"):
-   |  _____^
- 8 | |         filename = filename[:-4]
-   | |________________________________^ FURB188
- 9 |   
-10 |       return filename
-   |
-   = help: Use removesuffix instead of assignment conditional upon endswith.
-
-ℹ Safe fix
-4 4 | # these should match
-5 5 | 
-6 6 | def remove_extension_via_slice(filename: str) -> str:
-7   |-    if filename.endswith(".txt"):
-8   |-        filename = filename[:-4]
-  7 |+    filename = filename.removesuffix(".txt")
-9 8 | 
-10 9 |     return filename
-11 10 | 
-
-FURB188.py:14:5: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
-   |
-13 |   def remove_extension_via_slice_len(filename: str, extension: str) -> str:
-14 |       if filename.endswith(extension):
-   |  _____^
-15 | |         filename = filename[:-len(extension)]
-   | |_____________________________________________^ FURB188
-16 |   
-17 |       return filename
-   |
-   = help: Use removesuffix instead of assignment conditional upon endswith.
-
-ℹ Safe fix
-11 11 | 
-12 12 | 
-13 13 | def remove_extension_via_slice_len(filename: str, extension: str) -> str:
-14    |-    if filename.endswith(extension):
-15    |-        filename = filename[:-len(extension)]
-   14 |+    filename = filename.removesuffix(extension)
-16 15 | 
-17 16 |     return filename
-18 17 | 
-
-FURB188.py:21:12: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
-   |
-20 | def remove_extension_via_ternary(filename: str) -> str:
-21 |     return filename[:-4] if filename.endswith(".txt") else filename
-   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB188
-   |
-   = help: Use removesuffix instead of ternary expression conditional upon endswith.
-
-ℹ Safe fix
-18 18 | 
-19 19 | 
-20 20 | def remove_extension_via_ternary(filename: str) -> str:
-21    |-    return filename[:-4] if filename.endswith(".txt") else filename
-   21 |+    return filename.removesuffix(".txt")
-22 22 | 
-23 23 | 
-24 24 | def remove_extension_via_ternary_with_len(filename: str, extension: str) -> str:
-
-FURB188.py:25:12: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
-   |
-24 | def remove_extension_via_ternary_with_len(filename: str, extension: str) -> str:
-25 |     return filename[:-len(extension)] if filename.endswith(extension) else filename
-   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB188
-   |
-   = help: Use removesuffix instead of ternary expression conditional upon endswith.
-
-ℹ Safe fix
-22 22 | 
-23 23 | 
-24 24 | def remove_extension_via_ternary_with_len(filename: str, extension: str) -> str:
-25    |-    return filename[:-len(extension)] if filename.endswith(extension) else filename
-   25 |+    return filename.removesuffix(extension)
-26 26 | 
-27 27 | 
-28 28 | def remove_prefix(filename: str) -> str:
-
-FURB188.py:29:12: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
-   |
-28 | def remove_prefix(filename: str) -> str:
-29 |     return filename[4:] if filename.startswith("abc-") else filename
-   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB188
-   |
-   = help: Use removeprefix instead of ternary expression conditional upon startswith.
-
-ℹ Safe fix
-26 26 | 
-27 27 | 
-28 28 | def remove_prefix(filename: str) -> str:
-29    |-    return filename[4:] if filename.startswith("abc-") else filename
-   29 |+    return filename.removeprefix("abc-")
-30 30 | 
-31 31 | 
-32 32 | def remove_prefix_via_len(filename: str, prefix: str) -> str:
-
-FURB188.py:33:12: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
-   |
-32 | def remove_prefix_via_len(filename: str, prefix: str) -> str:
-33 |     return filename[len(prefix):] if filename.startswith(prefix) else filename
-   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB188
-   |
-   = help: Use removeprefix instead of ternary expression conditional upon startswith.
-
-ℹ Safe fix
-30 30 | 
-31 31 | 
-32 32 | def remove_prefix_via_len(filename: str, prefix: str) -> str:
-33    |-    return filename[len(prefix):] if filename.startswith(prefix) else filename
-   33 |+    return filename.removeprefix(prefix)
-34 34 | 
-35 35 | 
-36 36 | # these should not
-
-FURB188.py:146:9: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
-    |
-144 |     SUFFIX = "suffix"
-145 | 
-146 |     x = foo.bar.baz[:-len(SUFFIX)] if foo.bar.baz.endswith(SUFFIX) else foo.bar.baz
-    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB188
-147 | 
-148 | def remove_prefix_comparable_literal_expr() -> None:
-    |
-    = help: Use removesuffix instead of ternary expression conditional upon endswith.
-
-ℹ Safe fix
-143 143 | 
-144 144 |     SUFFIX = "suffix"
-145 145 | 
-146     |-    x = foo.bar.baz[:-len(SUFFIX)] if foo.bar.baz.endswith(SUFFIX) else foo.bar.baz
-    146 |+    x = foo.bar.baz.removesuffix(SUFFIX)
-147 147 | 
-148 148 | def remove_prefix_comparable_literal_expr() -> None:
-149 149 |     return ("abc" "def")[3:] if ("abc" "def").startswith("abc") else "abc" "def"
-
-FURB188.py:149:12: FURB188 [*] Prefer `removeprefix` over conditionally replacing with slice.
-    |
-148 | def remove_prefix_comparable_literal_expr() -> None:
-149 |     return ("abc" "def")[3:] if ("abc" "def").startswith("abc") else "abc" "def"
-    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB188
-150 | 
-151 | def shadow_builtins(filename: str, extension: str) -> None:
-    |
-    = help: Use removeprefix instead of ternary expression conditional upon startswith.
-
-ℹ Safe fix
-146 146 |     x = foo.bar.baz[:-len(SUFFIX)] if foo.bar.baz.endswith(SUFFIX) else foo.bar.baz
-147 147 | 
-148 148 | def remove_prefix_comparable_literal_expr() -> None:
-149     |-    return ("abc" "def")[3:] if ("abc" "def").startswith("abc") else "abc" "def"
-    149 |+    return "abc" "def".removeprefix("abc")
-150 150 | 
-151 151 | def shadow_builtins(filename: str, extension: str) -> None:
-152 152 |     from builtins import len as builtins_len
-
-FURB188.py:154:12: FURB188 [*] Prefer `removesuffix` over conditionally replacing with slice.
-    |
-152 |     from builtins import len as builtins_len
-153 | 
-154 |     return filename[:-builtins_len(extension)] if filename.endswith(extension) else filename
-    |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB188
-    |
-    = help: Use removesuffix instead of ternary expression conditional upon endswith.
-
-ℹ Safe fix
-151 151 | def shadow_builtins(filename: str, extension: str) -> None:
-152 152 |     from builtins import len as builtins_len
-153 153 | 
-154     |-    return filename[:-builtins_len(extension)] if filename.endswith(extension) else filename
-    154 |+    return filename.removesuffix(extension)
--- a/crates/ruff_linter/src/rules/ruff/mod.rs
+++ b/crates/ruff_linter/src/rules/ruff/mod.rs
@@ -58,7 +58,6 @@ mod tests {
    #[test_case(Rule::AssertWithPrintMessage, Path::new("RUF030.py"))]
    #[test_case(Rule::IncorrectlyParenthesizedTupleInSubscript, Path::new("RUF031.py"))]
    #[test_case(Rule::DecimalFromFloatLiteral, Path::new("RUF032.py"))]
-    #[test_case(Rule::UselessIfElse, Path::new("RUF034.py"))]
    #[test_case(Rule::RedirectedNOQA, Path::new("RUF101.py"))]
    #[test_case(Rule::PostInitDefault, Path::new("RUF033.py"))]
    fn rules(rule_code: Rule, path: &Path) -> Result<()> {
--- a/crates/ruff_linter/src/rules/ruff/rules/decimal_from_float_literal.rs
+++ b/crates/ruff_linter/src/rules/ruff/rules/decimal_from_float_literal.rs
@@ -1,10 +1,7 @@
-use std::fmt;
-
 use ruff_diagnostics::{AlwaysFixableViolation, Diagnostic, Edit, Fix};
 use ruff_macros::{derive_message_formats, violation};
-use ruff_python_ast as ast;
+use ruff_python_ast::{self as ast};
 use ruff_python_codegen::Stylist;
-use ruff_source_file::Locator;
 use ruff_text_size::{Ranged, TextRange};

 use crate::checkers::ast::Checker;
@@ -52,90 +49,37 @@ pub(crate) fn decimal_from_float_literal_syntax(checker: &mut Checker, call: &as
        return;
    };

-    if let Some(float) = extract_float_literal(arg, Sign::Positive) {
-        if checker
-            .semantic()
-            .resolve_qualified_name(call.func.as_ref())
-            .is_some_and(|qualified_name| {
-                matches!(qualified_name.segments(), ["decimal", "Decimal"])
-            })
-        {
-            let diagnostic = Diagnostic::new(DecimalFromFloatLiteral, arg.range()).with_fix(
-                fix_float_literal(arg.range(), float, checker.locator(), checker.stylist()),
-            );
-            checker.diagnostics.push(diagnostic);
-        }
+    if !is_arg_float_literal(arg) {
+        return;
+    }
+
+    if checker
+        .semantic()
+        .resolve_qualified_name(call.func.as_ref())
+        .is_some_and(|qualified_name| matches!(qualified_name.segments(), ["decimal", "Decimal"]))
+    {
+        let diagnostic =
+            Diagnostic::new(DecimalFromFloatLiteral, arg.range()).with_fix(fix_float_literal(
+                arg.range(),
+                &checker.generator().expr(arg),
+                checker.stylist(),
+            ));
+        checker.diagnostics.push(diagnostic);
    }
 }

-#[derive(Debug, Clone, Copy)]
-enum Sign {
-    Positive,
-    Negative,
-}
-
-impl Sign {
-    const fn as_str(self) -> &'static str {
-        match self {
-            Self::Positive => "",
-            Self::Negative => "-",
-        }
-    }
-
-    const fn flip(self) -> Self {
-        match self {
-            Self::Negative => Self::Positive,
-            Self::Positive => Self::Negative,
-        }
-    }
-}
-
-impl fmt::Display for Sign {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.write_str(self.as_str())
-    }
-}
-
-#[derive(Debug, Copy, Clone)]
-struct Float {
-    /// The range of the float excluding the sign.
-    /// E.g. for `+--+-+-4.3`, this will be the range of `4.3`
-    value_range: TextRange,
-    /// The resolved sign of the float (either `-` or `+`)
-    sign: Sign,
-}
-
-fn extract_float_literal(arg: &ast::Expr, sign: Sign) -> Option<Float> {
+fn is_arg_float_literal(arg: &ast::Expr) -> bool {
    match arg {
-        ast::Expr::NumberLiteral(number_literal_expr) if number_literal_expr.value.is_float() => {
-            Some(Float {
-                value_range: arg.range(),
-                sign,
-            })
-        }
-        ast::Expr::UnaryOp(ast::ExprUnaryOp {
-            operand,
-            op: ast::UnaryOp::UAdd,
+        ast::Expr::NumberLiteral(ast::ExprNumberLiteral {
+            value: ast::Number::Float(_),
            ..
-        }) => extract_float_literal(operand, sign),
-        ast::Expr::UnaryOp(ast::ExprUnaryOp {
-            operand,
-            op: ast::UnaryOp::USub,
-            ..
-        }) => extract_float_literal(operand, sign.flip()),
-        _ => None,
+        }) => true,
+        ast::Expr::UnaryOp(ast::ExprUnaryOp { operand, .. }) => is_arg_float_literal(operand),
+        _ => false,
    }
 }

-fn fix_float_literal(
-    original_range: TextRange,
-    float: Float,
-    locator: &Locator,
-    stylist: &Stylist,
-) -> Fix {
-    let quote = stylist.quote();
-    let Float { value_range, sign } = float;
-    let float_value = locator.slice(value_range);
-    let content = format!("{quote}{sign}{float_value}{quote}");
-    Fix::unsafe_edit(Edit::range_replacement(content, original_range))
+fn fix_float_literal(range: TextRange, float_literal: &str, stylist: &Stylist) -> Fix {
+    let content = format!("{quote}{float_literal}{quote}", quote = stylist.quote());
+    Fix::unsafe_edit(Edit::range_replacement(content, range))
 }
--- a/crates/ruff_linter/src/rules/ruff/rules/invalid_formatter_suppression_comment.rs
+++ b/crates/ruff_linter/src/rules/ruff/rules/invalid_formatter_suppression_comment.rs
@@ -75,7 +75,7 @@ pub(crate) fn ignored_formatter_suppression_comment(checker: &mut Checker, suite
        .into_iter()
        .filter_map(|range| {
            Some(SuppressionComment {
-                range,
+                range: *range,
                kind: SuppressionKind::from_comment(locator.slice(range))?,
            })
        })
--- a/crates/ruff_linter/src/rules/ruff/rules/mod.rs
+++ b/crates/ruff_linter/src/rules/ruff/rules/mod.rs
@@ -29,7 +29,6 @@ pub(crate) use unnecessary_iterable_allocation_for_first_element::*;
 pub(crate) use unnecessary_key_check::*;
 pub(crate) use unused_async::*;
 pub(crate) use unused_noqa::*;
-pub(crate) use useless_if_else::*;
 pub(crate) use zip_instead_of_pairwise::*;

 mod ambiguous_unicode_character;
@@ -67,7 +66,6 @@ mod unnecessary_iterable_allocation_for_first_element;
 mod unnecessary_key_check;
 mod unused_async;
 mod unused_noqa;
-mod useless_if_else;
 mod zip_instead_of_pairwise;

 #[derive(Clone, Copy)]
--- a/crates/ruff_linter/src/rules/ruff/rules/useless_if_else.rs
+++ b/crates/ruff_linter/src/rules/ruff/rules/useless_if_else.rs
@@ -1,55 +0,0 @@
-use crate::checkers::ast::Checker;
-use ruff_diagnostics::{Diagnostic, Violation};
-use ruff_macros::{derive_message_formats, violation};
-use ruff_python_ast as ast;
-use ruff_python_ast::comparable::ComparableExpr;
-
-/// ## What it does
-/// Checks for useless if-else conditions with identical arms.
-///
-/// ## Why is this bad?
-/// Useless if-else conditions add unnecessary complexity to the code without
-/// providing any logical benefit.
-///
-/// Assigning the value directly is clearer and more explicit, and
-/// should be preferred.
-///
-/// ## Example
-/// ```python
-/// # Bad
-/// foo = x if y else x
-/// ```
-///
-/// Use instead:
-/// ```python
-/// # Good
-/// foo = x
-/// ```
-#[violation]
-pub struct UselessIfElse;
-
-impl Violation for UselessIfElse {
-    #[derive_message_formats]
-    fn message(&self) -> String {
-        format!("Useless if-else condition")
-    }
-}
-
-/// RUF031
-pub(crate) fn useless_if_else(checker: &mut Checker, if_expr: &ast::ExprIf) {
-    let ast::ExprIf {
-        body,
-        orelse,
-        range,
-        ..
-    } = if_expr;
-
-    // Skip if the body and orelse are not the same
-    if ComparableExpr::from(body) != ComparableExpr::from(orelse) {
-        return;
-    }
-
-    checker
-        .diagnostics
-        .push(Diagnostic::new(UselessIfElse, *range));
-}
--- a/crates/ruff_linter/src/rules/ruff/snapshots/ruff_linterrulesrufftestsRUF032_RUF032.py.snap
+++ b/crates/ruff_linter/src/rules/ruff/snapshots/ruff_linterrulesrufftestsRUF032_RUF032.py.snap
@@ -127,105 +127,65 @@ RUF032.py:45:15: RUF032 [*] `Decimal()` called with float literal argument
 47 47 | val = Decimal("-10.0")
 48 48 | 

-RUF032.py:56:15: RUF032 [*] `Decimal()` called with float literal argument
+RUF032.py:81:23: RUF032 [*] `Decimal()` called with float literal argument
   |
-54 | val = Decimal(~4.0) # Skip
-55 | 
-56 | val = Decimal(++4.0) # Suggest `Decimal("4.0")`
-   |               ^^^^^ RUF032
-57 | 
-58 | val = Decimal(-+--++--4.0) # Suggest `Decimal("-4.0")` 
-   |
-   = help: Use a string literal instead
-
-ℹ Unsafe fix
-53 53 | # See https://github.com/astral-sh/ruff/issues/13258
-54 54 | val = Decimal(~4.0) # Skip
-55 55 | 
-56    |-val = Decimal(++4.0) # Suggest `Decimal("4.0")`
-   56 |+val = Decimal("4.0") # Suggest `Decimal("4.0")`
-57 57 | 
-58 58 | val = Decimal(-+--++--4.0) # Suggest `Decimal("-4.0")` 
-59 59 | 
-
-RUF032.py:58:15: RUF032 [*] `Decimal()` called with float literal argument
-   |
-56 | val = Decimal(++4.0) # Suggest `Decimal("4.0")`
-57 | 
-58 | val = Decimal(-+--++--4.0) # Suggest `Decimal("-4.0")` 
-   |               ^^^^^^^^^^^ RUF032
-   |
-   = help: Use a string literal instead
-
-ℹ Unsafe fix
-55 55 | 
-56 56 | val = Decimal(++4.0) # Suggest `Decimal("4.0")`
-57 57 | 
-58    |-val = Decimal(-+--++--4.0) # Suggest `Decimal("-4.0")` 
-   58 |+val = Decimal("-4.0") # Suggest `Decimal("-4.0")` 
-59 59 | 
-60 60 | 
-61 61 | # Tests with shadowed name
-
-RUF032.py:88:23: RUF032 [*] `Decimal()` called with float literal argument
-   |
-86 | # Retest with fully qualified import
-87 | 
-88 | val = decimal.Decimal(0.0)  # Should error
+79 | # Retest with fully qualified import
+80 | 
+81 | val = decimal.Decimal(0.0)  # Should error
   |                       ^^^ RUF032
-89 | 
-90 | val = decimal.Decimal("0.0")
+82 | 
+83 | val = decimal.Decimal("0.0")
   |
   = help: Use a string literal instead

 ℹ Unsafe fix
-85 85 | 
-86 86 | # Retest with fully qualified import
-87 87 | 
-88    |-val = decimal.Decimal(0.0)  # Should error
-   88 |+val = decimal.Decimal("0.0")  # Should error
-89 89 | 
-90 90 | val = decimal.Decimal("0.0")
-91 91 | 
+78 78 | 
+79 79 | # Retest with fully qualified import
+80 80 | 
+81    |-val = decimal.Decimal(0.0)  # Should error
+   81 |+val = decimal.Decimal("0.0")  # Should error
+82 82 | 
+83 83 | val = decimal.Decimal("0.0")
+84 84 | 

-RUF032.py:92:23: RUF032 [*] `Decimal()` called with float literal argument
+RUF032.py:85:23: RUF032 [*] `Decimal()` called with float literal argument
   |
-90 | val = decimal.Decimal("0.0")
-91 | 
-92 | val = decimal.Decimal(10.0)  # Should error
+83 | val = decimal.Decimal("0.0")
+84 | 
+85 | val = decimal.Decimal(10.0)  # Should error
   |                       ^^^^ RUF032
-93 | 
-94 | val = decimal.Decimal("10.0")
+86 | 
+87 | val = decimal.Decimal("10.0")
   |
   = help: Use a string literal instead

 ℹ Unsafe fix
-89 89 | 
-90 90 | val = decimal.Decimal("0.0")
-91 91 | 
-92    |-val = decimal.Decimal(10.0)  # Should error
-   92 |+val = decimal.Decimal("10.0")  # Should error
-93 93 | 
-94 94 | val = decimal.Decimal("10.0")
-95 95 | 
+82 82 | 
+83 83 | val = decimal.Decimal("0.0")
+84 84 | 
+85    |-val = decimal.Decimal(10.0)  # Should error
+   85 |+val = decimal.Decimal("10.0")  # Should error
+86 86 | 
+87 87 | val = decimal.Decimal("10.0")
+88 88 | 

-RUF032.py:96:23: RUF032 [*] `Decimal()` called with float literal argument
+RUF032.py:89:23: RUF032 [*] `Decimal()` called with float literal argument
   |
-94 | val = decimal.Decimal("10.0")
-95 | 
-96 | val = decimal.Decimal(-10.0)  # Should error
+87 | val = decimal.Decimal("10.0")
+88 | 
+89 | val = decimal.Decimal(-10.0)  # Should error
   |                       ^^^^^ RUF032
-97 | 
-98 | val = decimal.Decimal("-10.0")
+90 | 
+91 | val = decimal.Decimal("-10.0")
   |
   = help: Use a string literal instead

 ℹ Unsafe fix
-93 93 | 
-94 94 | val = decimal.Decimal("10.0")
-95 95 | 
-96    |-val = decimal.Decimal(-10.0)  # Should error
-   96 |+val = decimal.Decimal("-10.0")  # Should error
-97 97 | 
-98 98 | val = decimal.Decimal("-10.0")
-99 99 |
+86 86 | 
+87 87 | val = decimal.Decimal("10.0")
+88 88 | 
+89    |-val = decimal.Decimal(-10.0)  # Should error
+   89 |+val = decimal.Decimal("-10.0")  # Should error
+90 90 | 
+91 91 | val = decimal.Decimal("-10.0")
+92 92 |
--- a/crates/ruff_linter/src/rules/ruff/snapshots/ruff_linterrulesrufftestsRUF034_RUF034.py.snap
+++ b/crates/ruff_linter/src/rules/ruff/snapshots/ruff_linterrulesrufftestsRUF034_RUF034.py.snap
@@ -1,27 +0,0 @@
---
-source: crates/ruff_linter/src/rules/ruff/mod.rs
---
-RUF034.py:5:5: RUF034 Useless if-else condition
-  |
-4 | # Invalid
-5 | x = 1 if True else 1
-  |     ^^^^^^^^^^^^^^^^ RUF034
-6 | 
-7 | # Invalid
-  |
-
-RUF034.py:8:5: RUF034 Useless if-else condition
-   |
- 7 | # Invalid
- 8 | x = "a" if True else "a"
-   |     ^^^^^^^^^^^^^^^^^^^^ RUF034
- 9 | 
-10 | # Invalid
-   |
-
-RUF034.py:11:5: RUF034 Useless if-else condition
-   |
-10 | # Invalid
-11 | x = 0.1 if False else 0.1
-   |     ^^^^^^^^^^^^^^^^^^^^^ RUF034
-   |
--- a/crates/ruff_python_ast/src/nodes.rs
+++ b/crates/ruff_python_ast/src/nodes.rs
@@ -3124,29 +3124,6 @@ impl Pattern {
            _ => false,
        }
    }
-
-    /// Checks if the [`Pattern`] is a [wildcard pattern].
-    ///
-    /// The following are wildcard patterns:
-    /// ```python
-    /// match subject:
-    ///     case _ as x: ...
-    ///     case _ | _: ...
-    ///     case _: ...
-    /// ```
-    ///
-    /// [wildcard pattern]: https://docs.python.org/3/reference/compound_stmts.html#wildcard-patterns
-    pub fn is_wildcard(&self) -> bool {
-        match self {
-            Pattern::MatchAs(PatternMatchAs { pattern, .. }) => {
-                pattern.as_deref().map_or(true, Pattern::is_wildcard)
-            }
-            Pattern::MatchOr(PatternMatchOr { patterns, .. }) => {
-                patterns.iter().all(Pattern::is_wildcard)
-            }
-            _ => false,
-        }
-    }
 }

 /// See also [MatchValue](https://docs.python.org/3/library/ast.html#ast.MatchValue)
--- a/crates/ruff_python_ast_integration_tests/tests/match_pattern.rs
+++ b/crates/ruff_python_ast_integration_tests/tests/match_pattern.rs
@@ -1,16 +0,0 @@
-use ruff_python_parser::parse_module;
-
-#[test]
-fn pattern_is_wildcard() {
-    let source_code = r"
-match subject:
-    case _ as x: ...
-    case _ | _: ...
-    case _: ...
-";
-    let parsed = parse_module(source_code).unwrap();
-    let cases = &parsed.syntax().body[0].as_match_stmt().unwrap().cases;
-    for case in cases {
-        assert!(case.pattern.is_wildcard());
-    }
-}
--- a/crates/ruff_python_parser/src/string.rs
+++ b/crates/ruff_python_parser/src/string.rs
@@ -97,8 +97,9 @@ impl StringParser {

    #[inline]
    fn next_char(&mut self) -> Option<char> {
-        self.source[self.cursor..].chars().next().inspect(|c| {
+        self.source[self.cursor..].chars().next().map(|c| {
            self.cursor += c.len_utf8();
+            c
        })
    }

--- a/crates/ruff_python_stdlib/src/builtins.rs
+++ b/crates/ruff_python_stdlib/src/builtins.rs
@@ -23,197 +23,182 @@ pub const MAGIC_GLOBALS: &[&str] = &[
    "__file__",
 ];

-static ALWAYS_AVAILABLE_BUILTINS: &[&str] = &[
-    "ArithmeticError",
-    "AssertionError",
-    "AttributeError",
-    "BaseException",
-    "BlockingIOError",
-    "BrokenPipeError",
-    "BufferError",
-    "BytesWarning",
-    "ChildProcessError",
-    "ConnectionAbortedError",
-    "ConnectionError",
-    "ConnectionRefusedError",
-    "ConnectionResetError",
-    "DeprecationWarning",
-    "EOFError",
-    "Ellipsis",
-    "EnvironmentError",
-    "Exception",
-    "False",
-    "FileExistsError",
-    "FileNotFoundError",
-    "FloatingPointError",
-    "FutureWarning",
-    "GeneratorExit",
-    "IOError",
-    "ImportError",
-    "ImportWarning",
-    "IndentationError",
-    "IndexError",
-    "InterruptedError",
-    "IsADirectoryError",
-    "KeyError",
-    "KeyboardInterrupt",
-    "LookupError",
-    "MemoryError",
-    "ModuleNotFoundError",
-    "NameError",
-    "None",
-    "NotADirectoryError",
-    "NotImplemented",
-    "NotImplementedError",
-    "OSError",
-    "OverflowError",
-    "PendingDeprecationWarning",
-    "PermissionError",
-    "ProcessLookupError",
-    "RecursionError",
-    "ReferenceError",
-    "ResourceWarning",
-    "RuntimeError",
-    "RuntimeWarning",
-    "StopAsyncIteration",
-    "StopIteration",
-    "SyntaxError",
-    "SyntaxWarning",
-    "SystemError",
-    "SystemExit",
-    "TabError",
-    "TimeoutError",
-    "True",
-    "TypeError",
-    "UnboundLocalError",
-    "UnicodeDecodeError",
-    "UnicodeEncodeError",
-    "UnicodeError",
-    "UnicodeTranslateError",
-    "UnicodeWarning",
-    "UserWarning",
-    "ValueError",
-    "Warning",
-    "ZeroDivisionError",
-    "__build_class__",
-    "__debug__",
-    "__doc__",
-    "__import__",
-    "__loader__",
-    "__name__",
-    "__package__",
-    "__spec__",
-    "abs",
-    "all",
-    "any",
-    "ascii",
-    "bin",
-    "bool",
-    "breakpoint",
-    "bytearray",
-    "bytes",
-    "callable",
-    "chr",
-    "classmethod",
-    "compile",
-    "complex",
-    "copyright",
-    "credits",
-    "delattr",
-    "dict",
-    "dir",
-    "divmod",
-    "enumerate",
-    "eval",
-    "exec",
-    "exit",
-    "filter",
-    "float",
-    "format",
-    "frozenset",
-    "getattr",
-    "globals",
-    "hasattr",
-    "hash",
-    "help",
-    "hex",
-    "id",
-    "input",
-    "int",
-    "isinstance",
-    "issubclass",
-    "iter",
-    "len",
-    "license",
-    "list",
-    "locals",
-    "map",
-    "max",
-    "memoryview",
-    "min",
-    "next",
-    "object",
-    "oct",
-    "open",
-    "ord",
-    "pow",
-    "print",
-    "property",
-    "quit",
-    "range",
-    "repr",
-    "reversed",
-    "round",
-    "set",
-    "setattr",
-    "slice",
-    "sorted",
-    "staticmethod",
-    "str",
-    "sum",
-    "super",
-    "tuple",
-    "type",
-    "vars",
-    "zip",
-];
-static PY310_PLUS_BUILTINS: &[&str] = &["EncodingWarning", "aiter", "anext"];
-static PY311_PLUS_BUILTINS: &[&str] = &["BaseExceptionGroup", "ExceptionGroup"];
-static PY313_PLUS_BUILTINS: &[&str] = &["PythonFinalizationError"];
-
 /// Return the list of builtins for the given Python minor version.
 ///
 /// Intended to be kept in sync with [`is_python_builtin`].
-pub fn python_builtins(minor_version: u8, is_notebook: bool) -> impl Iterator<Item = &'static str> {
-    let py310_builtins = if minor_version >= 10 {
-        Some(PY310_PLUS_BUILTINS)
-    } else {
-        None
-    };
-    let py311_builtins = if minor_version >= 11 {
-        Some(PY311_PLUS_BUILTINS)
-    } else {
-        None
-    };
-    let py313_builtins = if minor_version >= 13 {
-        Some(PY313_PLUS_BUILTINS)
-    } else {
-        None
-    };
-    let ipython_builtins = if is_notebook {
-        Some(IPYTHON_BUILTINS)
-    } else {
-        None
-    };
+pub fn python_builtins(minor_version: u8, is_notebook: bool) -> Vec<&'static str> {
+    let mut builtins = vec![
+        "ArithmeticError",
+        "AssertionError",
+        "AttributeError",
+        "BaseException",
+        "BlockingIOError",
+        "BrokenPipeError",
+        "BufferError",
+        "BytesWarning",
+        "ChildProcessError",
+        "ConnectionAbortedError",
+        "ConnectionError",
+        "ConnectionRefusedError",
+        "ConnectionResetError",
+        "DeprecationWarning",
+        "EOFError",
+        "Ellipsis",
+        "EnvironmentError",
+        "Exception",
+        "False",
+        "FileExistsError",
+        "FileNotFoundError",
+        "FloatingPointError",
+        "FutureWarning",
+        "GeneratorExit",
+        "IOError",
+        "ImportError",
+        "ImportWarning",
+        "IndentationError",
+        "IndexError",
+        "InterruptedError",
+        "IsADirectoryError",
+        "KeyError",
+        "KeyboardInterrupt",
+        "LookupError",
+        "MemoryError",
+        "ModuleNotFoundError",
+        "NameError",
+        "None",
+        "NotADirectoryError",
+        "NotImplemented",
+        "NotImplementedError",
+        "OSError",
+        "OverflowError",
+        "PendingDeprecationWarning",
+        "PermissionError",
+        "ProcessLookupError",
+        "RecursionError",
+        "ReferenceError",
+        "ResourceWarning",
+        "RuntimeError",
+        "RuntimeWarning",
+        "StopAsyncIteration",
+        "StopIteration",
+        "SyntaxError",
+        "SyntaxWarning",
+        "SystemError",
+        "SystemExit",
+        "TabError",
+        "TimeoutError",
+        "True",
+        "TypeError",
+        "UnboundLocalError",
+        "UnicodeDecodeError",
+        "UnicodeEncodeError",
+        "UnicodeError",
+        "UnicodeTranslateError",
+        "UnicodeWarning",
+        "UserWarning",
+        "ValueError",
+        "Warning",
+        "ZeroDivisionError",
+        "__build_class__",
+        "__debug__",
+        "__doc__",
+        "__import__",
+        "__loader__",
+        "__name__",
+        "__package__",
+        "__spec__",
+        "abs",
+        "all",
+        "any",
+        "ascii",
+        "bin",
+        "bool",
+        "breakpoint",
+        "bytearray",
+        "bytes",
+        "callable",
+        "chr",
+        "classmethod",
+        "compile",
+        "complex",
+        "copyright",
+        "credits",
+        "delattr",
+        "dict",
+        "dir",
+        "divmod",
+        "enumerate",
+        "eval",
+        "exec",
+        "exit",
+        "filter",
+        "float",
+        "format",
+        "frozenset",
+        "getattr",
+        "globals",
+        "hasattr",
+        "hash",
+        "help",
+        "hex",
+        "id",
+        "input",
+        "int",
+        "isinstance",
+        "issubclass",
+        "iter",
+        "len",
+        "license",
+        "list",
+        "locals",
+        "map",
+        "max",
+        "memoryview",
+        "min",
+        "next",
+        "object",
+        "oct",
+        "open",
+        "ord",
+        "pow",
+        "print",
+        "property",
+        "quit",
+        "range",
+        "repr",
+        "reversed",
+        "round",
+        "set",
+        "setattr",
+        "slice",
+        "sorted",
+        "staticmethod",
+        "str",
+        "sum",
+        "super",
+        "tuple",
+        "type",
+        "vars",
+        "zip",
+    ];

-    py310_builtins
-        .into_iter()
-        .chain(py311_builtins)
-        .chain(py313_builtins)
-        .chain(ipython_builtins)
-        .flatten()
-        .chain(ALWAYS_AVAILABLE_BUILTINS)
-        .copied()
+    if minor_version >= 10 {
+        builtins.extend(&["EncodingWarning", "aiter", "anext"]);
+    }
+
+    if minor_version >= 11 {
+        builtins.extend(&["BaseExceptionGroup", "ExceptionGroup"]);
+    }
+
+    if minor_version >= 13 {
+        builtins.push("PythonFinalizationError");
+    }
+
+    if is_notebook {
+        builtins.extend(IPYTHON_BUILTINS);
+    }
+
+    builtins
 }

 /// Returns `true` if the given name is that of a Python builtin.
@@ -385,22 +370,6 @@ pub fn is_python_builtin(name: &str, minor_version: u8, is_notebook: bool) -> bo
    )
 }

-/// Return `Some(version)`, where `version` corresponds to the Python minor version
-/// in which the builtin was added
-pub fn version_builtin_was_added(name: &str) -> Option<u8> {
-    if PY310_PLUS_BUILTINS.contains(&name) {
-        Some(10)
-    } else if PY311_PLUS_BUILTINS.contains(&name) {
-        Some(11)
-    } else if PY313_PLUS_BUILTINS.contains(&name) {
-        Some(13)
-    } else if ALWAYS_AVAILABLE_BUILTINS.contains(&name) {
-        Some(0)
-    } else {
-        None
-    }
-}
-
 /// Returns `true` if the given name is that of a Python builtin iterator.
 pub fn is_iterator(name: &str) -> bool {
    matches!(
--- a/crates/ruff_python_trivia/src/comment_ranges.rs
+++ b/crates/ruff_python_trivia/src/comment_ranges.rs
@@ -215,10 +215,10 @@ impl Debug for CommentRanges {
 }

 impl<'a> IntoIterator for &'a CommentRanges {
-    type Item = TextRange;
-    type IntoIter = std::iter::Copied<std::slice::Iter<'a, TextRange>>;
+    type Item = &'a TextRange;
+    type IntoIter = std::slice::Iter<'a, TextRange>;

    fn into_iter(self) -> Self::IntoIter {
-        self.raw.iter().copied()
+        self.raw.iter()
    }
 }
--- a/crates/ruff_server/src/edit.rs
+++ b/crates/ruff_server/src/edit.rs
@@ -11,8 +11,8 @@ use lsp_types::{PositionEncodingKind, Url};
 pub use notebook::NotebookDocument;
 pub(crate) use range::{NotebookRange, RangeExt, ToRangeExt};
 pub(crate) use replacement::Replacement;
+pub(crate) use text_document::DocumentVersion;
 pub use text_document::TextDocument;
-pub(crate) use text_document::{DocumentVersion, LanguageId};

 use crate::{fix::Fixes, session::ResolvedClientCapabilities};

--- a/crates/ruff_server/src/edit/text_document.rs
+++ b/crates/ruff_server/src/edit/text_document.rs
@@ -20,23 +20,6 @@ pub struct TextDocument {
    /// The latest version of the document, set by the LSP client. The server will panic in
    /// debug mode if we attempt to update the document with an 'older' version.
    version: DocumentVersion,
-    /// The language ID of the document as provided by the client.
-    language_id: Option<LanguageId>,
-}
-
-#[derive(Debug, Copy, Clone, PartialEq, Eq)]
-pub enum LanguageId {
-    Python,
-    Other,
-}
-
-impl From<&str> for LanguageId {
-    fn from(language_id: &str) -> Self {
-        match language_id {
-            "python" => Self::Python,
-            _ => Self::Other,
-        }
-    }
 }

 impl TextDocument {
@@ -46,16 +29,9 @@ impl TextDocument {
            contents,
            index,
            version,
-            language_id: None,
        }
    }

-    #[must_use]
-    pub fn with_language_id(mut self, language_id: &str) -> Self {
-        self.language_id = Some(LanguageId::from(language_id));
-        self
-    }
-
    pub fn into_contents(self) -> String {
        self.contents
    }
@@ -72,10 +48,6 @@ impl TextDocument {
        self.version
    }

-    pub fn language_id(&self) -> Option<LanguageId> {
-        self.language_id
-    }
-
    pub fn apply_changes(
        &mut self,
        changes: Vec<lsp_types::TextDocumentContentChangeEvent>,
--- a/crates/ruff_server/src/fix.rs
+++ b/crates/ruff_server/src/fix.rs
@@ -38,7 +38,6 @@ pub(crate) fn fix_all(
            file_resolver_settings,
            Some(linter_settings),
            None,
-            query.text_document_language_id(),
        ) {
            return Ok(Fixes::default());
        }
--- a/crates/ruff_server/src/lint.rs
+++ b/crates/ruff_server/src/lint.rs
@@ -77,7 +77,6 @@ pub(crate) fn check(
            file_resolver_settings,
            Some(linter_settings),
            None,
-            query.text_document_language_id(),
        ) {
            return DiagnosticsMap::default();
        }
--- a/crates/ruff_server/src/resolve.rs
+++ b/crates/ruff_server/src/resolve.rs
@@ -4,8 +4,6 @@ use ruff_linter::settings::LinterSettings;
 use ruff_workspace::resolver::{match_any_exclusion, match_any_inclusion};
 use ruff_workspace::{FileResolverSettings, FormatterSettings};

-use crate::edit::LanguageId;
-
 /// Return `true` if the document at the given [`Path`] should be excluded.
 ///
 /// The tool-specific settings should be provided if the request for the document is specific to
@@ -21,7 +19,6 @@ pub(crate) fn is_document_excluded(
    resolver_settings: &FileResolverSettings,
    linter_settings: Option<&LinterSettings>,
    formatter_settings: Option<&FormatterSettings>,
-    language_id: Option<LanguageId>,
 ) -> bool {
    if let Some(exclusion) = match_any_exclusion(
        path,
@@ -41,14 +38,8 @@ pub(crate) fn is_document_excluded(
    ) {
        tracing::debug!("Included path via `{}`: {}", inclusion, path.display());
        false
-    } else if let Some(LanguageId::Python) = language_id {
-        tracing::debug!("Included path via Python language ID: {}", path.display());
-        false
    } else {
-        tracing::debug!(
-            "Ignored path as it's not in the inclusion set: {}",
-            path.display()
-        );
+        // Path is excluded by not being in the inclusion set.
        true
    }
 }
--- a/crates/ruff_server/src/server/api/notifications/did_open.rs
+++ b/crates/ruff_server/src/server/api/notifications/did_open.rs
@@ -21,14 +21,11 @@ impl super::SyncNotificationHandler for DidOpen {
        types::DidOpenTextDocumentParams {
            text_document:
                types::TextDocumentItem {
-                    uri,
-                    text,
-                    version,
-                    language_id,
+                    uri, text, version, ..
                },
        }: types::DidOpenTextDocumentParams,
    ) -> Result<()> {
-        let document = TextDocument::new(text, version).with_language_id(&language_id);
+        let document = TextDocument::new(text, version);

        session.open_text_document(uri.clone(), document);

--- a/crates/ruff_server/src/server/api/requests/format.rs
+++ b/crates/ruff_server/src/server/api/requests/format.rs
@@ -90,7 +90,6 @@ fn format_text_document(
            file_resolver_settings,
            None,
            Some(formatter_settings),
-            text_document.language_id(),
        ) {
            return Ok(None);
        }
--- a/crates/ruff_server/src/server/api/requests/format_range.rs
+++ b/crates/ruff_server/src/server/api/requests/format_range.rs
@@ -54,7 +54,6 @@ fn format_text_document_range(
            file_resolver_settings,
            None,
            Some(formatter_settings),
-            text_document.language_id(),
        ) {
            return Ok(None);
        }
--- a/crates/ruff_server/src/session/index.rs
+++ b/crates/ruff_server/src/session/index.rs
@@ -9,7 +9,6 @@ use rustc_hash::FxHashMap;

 pub(crate) use ruff_settings::RuffSettings;

-use crate::edit::LanguageId;
 use crate::{
    edit::{DocumentKey, DocumentVersion, NotebookDocument},
    PositionEncoding, TextDocument,
@@ -604,12 +603,4 @@ impl DocumentQuery {
                .and_then(|cell_uri| notebook.cell_document_by_uri(cell_uri)),
        }
    }
-
-    pub(crate) fn text_document_language_id(&self) -> Option<LanguageId> {
-        if let DocumentQuery::Text { document, .. } = self {
-            document.language_id()
-        } else {
-            None
-        }
-    }
 }
--- a/crates/ruff_server/src/session/index/ruff_settings.rs
+++ b/crates/ruff_server/src/session/index/ruff_settings.rs
@@ -340,7 +340,7 @@ impl<'a> ConfigurationTransformer for EditorConfigurationTransformer<'a> {

        // Merge in the editor-specified configuration file, if it exists.
        let editor_configuration = if let Some(config_file_path) = configuration {
-            match open_configuration_file(&config_file_path) {
+            match open_configuration_file(&config_file_path, project_root) {
                Ok(config_from_file) => editor_configuration.combine(config_from_file),
                Err(err) => {
                    tracing::error!("Unable to find editor-specified configuration file: {err}");
@@ -363,18 +363,11 @@ impl<'a> ConfigurationTransformer for EditorConfigurationTransformer<'a> {
    }
 }

-fn open_configuration_file(config_path: &Path) -> crate::Result<Configuration> {
-    ruff_workspace::resolver::resolve_configuration(
-        config_path,
-        Relativity::Parent,
-        &IdentityTransformer,
-    )
-}
+fn open_configuration_file(
+    config_path: &Path,
+    project_root: &Path,
+) -> crate::Result<Configuration> {
+    let options = ruff_workspace::pyproject::load_options(config_path)?;

-struct IdentityTransformer;
-
-impl ConfigurationTransformer for IdentityTransformer {
-    fn transform(&self, config: Configuration) -> Configuration {
-        config
-    }
+    Configuration::from_options(options, Some(config_path), project_root)
 }
--- a/crates/ruff_wasm/Cargo.toml
+++ b/crates/ruff_wasm/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "ruff_wasm"
-version = "0.6.5"
+version = "0.6.3"
 publish = false
 authors = { workspace = true }
 edition = { workspace = true }
--- a/crates/ruff_workspace/src/pyproject.rs
+++ b/crates/ruff_workspace/src/pyproject.rs
@@ -140,7 +140,7 @@ pub fn find_user_settings_toml() -> Option<PathBuf> {
 }

 /// Load `Options` from a `pyproject.toml` or `ruff.toml` file.
-pub(super) fn load_options<P: AsRef<Path>>(path: P) -> Result<Options> {
+pub fn load_options<P: AsRef<Path>>(path: P) -> Result<Options> {
    if path.as_ref().ends_with("pyproject.toml") {
        let pyproject = parse_pyproject_toml(&path)?;
        let mut ruff = pyproject
--- a/crates/ruff_workspace/src/resolver.rs
+++ b/crates/ruff_workspace/src/resolver.rs
@@ -263,7 +263,7 @@ pub trait ConfigurationTransformer {
 // configuration file extends another in the same path, we'll re-parse the same
 // file at least twice (possibly more than twice, since we'll also parse it when
 // resolving the "default" configuration).
-pub fn resolve_configuration(
+fn resolve_configuration(
    pyproject: &Path,
    relativity: Relativity,
    transformer: &dyn ConfigurationTransformer,
--- a/docs/formatter/black.md
+++ b/docs/formatter/black.md
@@ -458,21 +458,19 @@ parentheses:

 ```python
 # Input
-for a, [b, d,] in c:
+for a, f(b,) in c:
    pass

 # Black
-for a, [
+for a, f(
    b,
-    d,
-] in c:
+) in c:
    pass

 # Ruff
-for a, [
+for a, f(
    b,
-    d,
-] in c:
+) in c:
    pass
 ```

--- a/docs/integrations.md
+++ b/docs/integrations.md
@@ -78,7 +78,7 @@ Ruff can be used as a [pre-commit](https://pre-commit.com) hook via [`ruff-pre-c
 ```yaml
 - repo: https://github.com/astral-sh/ruff-pre-commit
  # Ruff version.
-  rev: v0.6.5
+  rev: v0.6.3
  hooks:
    # Run the linter.
    - id: ruff
@@ -91,7 +91,7 @@ To enable lint fixes, add the `--fix` argument to the lint hook:
 ```yaml
 - repo: https://github.com/astral-sh/ruff-pre-commit
  # Ruff version.
-  rev: v0.6.5
+  rev: v0.6.3
  hooks:
    # Run the linter.
    - id: ruff
@@ -105,7 +105,7 @@ To run the hooks over Jupyter Notebooks too, add `jupyter` to the list of allowe
 ```yaml
 - repo: https://github.com/astral-sh/ruff-pre-commit
  # Ruff version.
-  rev: v0.6.5
+  rev: v0.6.3
  hooks:
    # Run the linter.
    - id: ruff
--- a/docs/requirements-insiders.txt
+++ b/docs/requirements-insiders.txt
@@ -1,5 +1,5 @@
 PyYAML==6.0.2
-ruff==0.6.4
+ruff==0.6.3
 mkdocs==1.6.1
 mkdocs-material @ git+ssh://git@github.com/astral-sh/mkdocs-material-insiders.git@38c0b8187325c3bab386b666daf3518ac036f2f4
 mkdocs-redirects==1.2.1
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,5 +1,5 @@
 PyYAML==6.0.2
-ruff==0.6.4
+ruff==0.6.3
 mkdocs==1.6.1
 mkdocs-material==9.1.18
 mkdocs-redirects==1.2.1
--- a/docs/stylesheets/extra.css
+++ b/docs/stylesheets/extra.css
@@ -109,3 +109,16 @@
    user-select: none;
 }

+/* Omits the nav title "Ruff" entirely unless on a small screen, in which case
+the nav title is needed for backwards navigation in the collapsible
+nav variant.
+
+See https://github.com/astral-sh/uv/issues/5130 */
+.md-nav__title {
+  display: none;
+}
+@media screen and (max-width: 1219px) {
+  .md-nav__title {
+    display: flex ;
+  }
+}
--- a/mkdocs.template.yml
+++ b/mkdocs.template.yml
@@ -4,16 +4,16 @@ theme:
  logo: assets/bolt.svg
  favicon: assets/favicon.ico
  features:
-    - navigation.instant
-    - navigation.instant.prefetch
-    - navigation.tracking
    - content.code.annotate
-    - toc.integrate
-    - toc.follow
-    - navigation.path
-    - navigation.top
    - content.code.copy
    - content.tabs.link
+    - navigation.footer
+    - navigation.instant
+    - navigation.instant.prefetch
+    - navigation.path
+    - navigation.top
+    - navigation.tracking
+    - toc.follow
  palette:
    # Note: Using the system theme works with the insiders version
    # https://squidfunk.github.io/mkdocs-material/setup/changing-the-colors/#automatic-light-dark-mode
@@ -37,7 +37,6 @@ repo_name: ruff
 site_author: charliermarsh
 site_url: https://docs.astral.sh/ruff/
 site_dir: site/ruff
-site_description: An extremely fast Python linter and code formatter, written in Rust.
 markdown_extensions:
  - admonition
  - pymdownx.details
@@ -72,6 +71,15 @@ not_in_nav: |
 extra:
  analytics:
    provider: fathom
+  social:
+    - icon: fontawesome/brands/github
+      link: https://github.com/astral-sh/ruff
+    - icon: fontawesome/brands/discord
+      link: https://discord.com/invite/astral-sh
+    - icon: fontawesome/brands/python
+      link: https://pypi.org/project/ruff/
+    - icon: fontawesome/brands/x-twitter
+      link: https://x.com/astral_sh
 validation:
  omitted_files: warn
  absolute_links: warn
--- a/playground/api/package-lock.json
+++ b/playground/api/package-lock.json
@@ -16,7 +16,7 @@
        "@cloudflare/workers-types": "^4.20230801.0",
        "miniflare": "^3.20230801.1",
        "typescript": "^5.1.6",
-        "wrangler": "3.75.0"
+        "wrangler": "3.73.0"
      }
    },
    "node_modules/@cloudflare/kv-asset-handler": {
@@ -128,9 +128,9 @@
      }
    },
    "node_modules/@cloudflare/workers-types": {
-      "version": "4.20240903.0",
-      "resolved": "https://registry.npmjs.org/@cloudflare/workers-types/-/workers-types-4.20240903.0.tgz",
-      "integrity": "sha512-a4mqgtVsPWg3JNNlQdLRE0Z6/mHr/uXa1ANDw6Zd7in438UCbeb+j7Z954Sf93G24jExpAn9VZ8kUUml0RwZbQ==",
+      "version": "4.20240821.1",
+      "resolved": "https://registry.npmjs.org/@cloudflare/workers-types/-/workers-types-4.20240821.1.tgz",
+      "integrity": "sha512-icAkbnAqgVl6ef9lgLTom8na+kj2RBw2ViPAQ586hbdj0xZcnrjK7P46Eu08OU9D/lNDgN2sKU/sxhe2iK/gIg==",
      "dev": true,
      "license": "MIT OR Apache-2.0"
    },
@@ -1105,9 +1105,9 @@
      }
    },
    "node_modules/miniflare": {
-      "version": "3.20240821.1",
-      "resolved": "https://registry.npmjs.org/miniflare/-/miniflare-3.20240821.1.tgz",
-      "integrity": "sha512-81qdiryDG7VXzZuoa0EwhkaIYYrn7+StRIrd/2i7SPqPUNICUBjbhFFKqTnvE1+fqIPPB6l8ShKFaFvmnZOASg==",
+      "version": "3.20240821.0",
+      "resolved": "https://registry.npmjs.org/miniflare/-/miniflare-3.20240821.0.tgz",
+      "integrity": "sha512-4BhLGpssQxM/O6TZmJ10GkT3wBJK6emFkZ3V87/HyvQmVt8zMxEBvyw5uv6kdtp+7F54Nw6IKFJjPUL8rFVQrQ==",
      "dev": true,
      "license": "MIT",
      "dependencies": {
@@ -1591,9 +1591,9 @@
      }
    },
    "node_modules/wrangler": {
-      "version": "3.75.0",
-      "resolved": "https://registry.npmjs.org/wrangler/-/wrangler-3.75.0.tgz",
-      "integrity": "sha512-CitNuNj0O1z6qbonUXmpUbxeWpU3nx28Kc4ZT33tMdeooQssb063Ie7+ZCdfS3kPhRHSwGdtOV22xFYytHON8w==",
+      "version": "3.73.0",
+      "resolved": "https://registry.npmjs.org/wrangler/-/wrangler-3.73.0.tgz",
+      "integrity": "sha512-VrdDR2OpvsCQp+r5Of3rDP1W64cNN/LHLVx1roULOlPS8PZiv7rUYgkwhdCQ61+HICAaeSxWYIzkL5+B9+8W3g==",
      "dev": true,
      "license": "MIT OR Apache-2.0",
      "dependencies": {
@@ -1605,7 +1605,7 @@
        "chokidar": "^3.5.3",
        "date-fns": "^3.6.0",
        "esbuild": "0.17.19",
-        "miniflare": "3.20240821.1",
+        "miniflare": "3.20240821.0",
        "nanoid": "^3.3.3",
        "path-to-regexp": "^6.2.0",
        "resolve": "^1.22.8",
--- a/playground/api/package.json
+++ b/playground/api/package.json
@@ -5,7 +5,7 @@
    "@cloudflare/workers-types": "^4.20230801.0",
    "miniflare": "^3.20230801.1",
    "typescript": "^5.1.6",
-    "wrangler": "3.75.0"
+    "wrangler": "3.73.0"
  },
  "private": true,
  "scripts": {
--- a/playground/package-lock.json
+++ b/playground/package-lock.json
@@ -14,8 +14,7 @@
        "monaco-editor": "^0.51.0",
        "react": "^18.2.0",
        "react-dom": "^18.2.0",
-        "react-resizable-panels": "^2.0.0",
-        "smol-toml": "^1.3.0"
+        "react-resizable-panels": "^2.0.0"
      },
      "devDependencies": {
        "@types/react": "^18.0.26",
@@ -874,13 +873,6 @@
        "win32"
      ]
    },
-    "node_modules/@rtsao/scc": {
-      "version": "1.1.0",
-      "resolved": "https://registry.npmjs.org/@rtsao/scc/-/scc-1.1.0.tgz",
-      "integrity": "sha512-zt6OdqaDoOnJ1ZYsCYGt9YmWzDXl4vQdKTyJev62gFhRGKdx7mcT54V9KIjg+d2wi9EXsPvAPKe7i7WjfVWB8g==",
-      "dev": true,
-      "license": "MIT"
-    },
    "node_modules/@swc/core": {
      "version": "1.5.24",
      "resolved": "https://registry.npmjs.org/@swc/core/-/core-1.5.24.tgz",
@@ -1146,17 +1138,17 @@
      }
    },
    "node_modules/@typescript-eslint/eslint-plugin": {
-      "version": "8.4.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.4.0.tgz",
-      "integrity": "sha512-rg8LGdv7ri3oAlenMACk9e+AR4wUV0yrrG+XKsGKOK0EVgeEDqurkXMPILG2836fW4ibokTB5v4b6Z9+GYQDEw==",
+      "version": "8.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.3.0.tgz",
+      "integrity": "sha512-FLAIn63G5KH+adZosDYiutqkOkYEx0nvcwNNfJAf+c7Ae/H35qWwTYvPZUKFj5AS+WfHG/WJJfWnDnyNUlp8UA==",
      "dev": true,
      "license": "MIT",
      "dependencies": {
        "@eslint-community/regexpp": "^4.10.0",
-        "@typescript-eslint/scope-manager": "8.4.0",
-        "@typescript-eslint/type-utils": "8.4.0",
-        "@typescript-eslint/utils": "8.4.0",
-        "@typescript-eslint/visitor-keys": "8.4.0",
+        "@typescript-eslint/scope-manager": "8.3.0",
+        "@typescript-eslint/type-utils": "8.3.0",
+        "@typescript-eslint/utils": "8.3.0",
+        "@typescript-eslint/visitor-keys": "8.3.0",
        "graphemer": "^1.4.0",
        "ignore": "^5.3.1",
        "natural-compare": "^1.4.0",
@@ -1180,16 +1172,16 @@
      }
    },
    "node_modules/@typescript-eslint/parser": {
-      "version": "8.4.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-8.4.0.tgz",
-      "integrity": "sha512-NHgWmKSgJk5K9N16GIhQ4jSobBoJwrmURaLErad0qlLjrpP5bECYg+wxVTGlGZmJbU03jj/dfnb6V9bw+5icsA==",
+      "version": "8.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-8.3.0.tgz",
+      "integrity": "sha512-h53RhVyLu6AtpUzVCYLPhZGL5jzTD9fZL+SYf/+hYOx2bDkyQXztXSc4tbvKYHzfMXExMLiL9CWqJmVz6+78IQ==",
      "dev": true,
      "license": "BSD-2-Clause",
      "dependencies": {
-        "@typescript-eslint/scope-manager": "8.4.0",
-        "@typescript-eslint/types": "8.4.0",
-        "@typescript-eslint/typescript-estree": "8.4.0",
-        "@typescript-eslint/visitor-keys": "8.4.0",
+        "@typescript-eslint/scope-manager": "8.3.0",
+        "@typescript-eslint/types": "8.3.0",
+        "@typescript-eslint/typescript-estree": "8.3.0",
+        "@typescript-eslint/visitor-keys": "8.3.0",
        "debug": "^4.3.4"
      },
      "engines": {
@@ -1209,14 +1201,14 @@
      }
    },
    "node_modules/@typescript-eslint/scope-manager": {
-      "version": "8.4.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/scope-manager/-/scope-manager-8.4.0.tgz",
-      "integrity": "sha512-n2jFxLeY0JmKfUqy3P70rs6vdoPjHK8P/w+zJcV3fk0b0BwRXC/zxRTEnAsgYT7MwdQDt/ZEbtdzdVC+hcpF0A==",
+      "version": "8.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/scope-manager/-/scope-manager-8.3.0.tgz",
+      "integrity": "sha512-mz2X8WcN2nVu5Hodku+IR8GgCOl4C0G/Z1ruaWN4dgec64kDBabuXyPAr+/RgJtumv8EEkqIzf3X2U5DUKB2eg==",
      "dev": true,
      "license": "MIT",
      "dependencies": {
-        "@typescript-eslint/types": "8.4.0",
-        "@typescript-eslint/visitor-keys": "8.4.0"
+        "@typescript-eslint/types": "8.3.0",
+        "@typescript-eslint/visitor-keys": "8.3.0"
      },
      "engines": {
        "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1227,14 +1219,14 @@
      }
    },
    "node_modules/@typescript-eslint/type-utils": {
-      "version": "8.4.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/type-utils/-/type-utils-8.4.0.tgz",
-      "integrity": "sha512-pu2PAmNrl9KX6TtirVOrbLPLwDmASpZhK/XU7WvoKoCUkdtq9zF7qQ7gna0GBZFN0hci0vHaSusiL2WpsQk37A==",
+      "version": "8.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/type-utils/-/type-utils-8.3.0.tgz",
+      "integrity": "sha512-wrV6qh//nLbfXZQoj32EXKmwHf4b7L+xXLrP3FZ0GOUU72gSvLjeWUl5J5Ue5IwRxIV1TfF73j/eaBapxx99Lg==",
      "dev": true,
      "license": "MIT",
      "dependencies": {
-        "@typescript-eslint/typescript-estree": "8.4.0",
-        "@typescript-eslint/utils": "8.4.0",
+        "@typescript-eslint/typescript-estree": "8.3.0",
+        "@typescript-eslint/utils": "8.3.0",
        "debug": "^4.3.4",
        "ts-api-utils": "^1.3.0"
      },
@@ -1252,9 +1244,9 @@
      }
    },
    "node_modules/@typescript-eslint/types": {
-      "version": "8.4.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/types/-/types-8.4.0.tgz",
-      "integrity": "sha512-T1RB3KQdskh9t3v/qv7niK6P8yvn7ja1mS7QK7XfRVL6wtZ8/mFs/FHf4fKvTA0rKnqnYxl/uHFNbnEt0phgbw==",
+      "version": "8.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/types/-/types-8.3.0.tgz",
+      "integrity": "sha512-y6sSEeK+facMaAyixM36dQ5NVXTnKWunfD1Ft4xraYqxP0lC0POJmIaL/mw72CUMqjY9qfyVfXafMeaUj0noWw==",
      "dev": true,
      "license": "MIT",
      "engines": {
@@ -1266,14 +1258,14 @@
      }
    },
    "node_modules/@typescript-eslint/typescript-estree": {
-      "version": "8.4.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-8.4.0.tgz",
-      "integrity": "sha512-kJ2OIP4dQw5gdI4uXsaxUZHRwWAGpREJ9Zq6D5L0BweyOrWsL6Sz0YcAZGWhvKnH7fm1J5YFE1JrQL0c9dd53A==",
+      "version": "8.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-8.3.0.tgz",
+      "integrity": "sha512-Mq7FTHl0R36EmWlCJWojIC1qn/ZWo2YiWYc1XVtasJ7FIgjo0MVv9rZWXEE7IK2CGrtwe1dVOxWwqXUdNgfRCA==",
      "dev": true,
      "license": "BSD-2-Clause",
      "dependencies": {
-        "@typescript-eslint/types": "8.4.0",
-        "@typescript-eslint/visitor-keys": "8.4.0",
+        "@typescript-eslint/types": "8.3.0",
+        "@typescript-eslint/visitor-keys": "8.3.0",
        "debug": "^4.3.4",
        "fast-glob": "^3.3.2",
        "is-glob": "^4.0.3",
@@ -1321,16 +1313,16 @@
      }
    },
    "node_modules/@typescript-eslint/utils": {
-      "version": "8.4.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/utils/-/utils-8.4.0.tgz",
-      "integrity": "sha512-swULW8n1IKLjRAgciCkTCafyTHHfwVQFt8DovmaF69sKbOxTSFMmIZaSHjqO9i/RV0wIblaawhzvtva8Nmm7lQ==",
+      "version": "8.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/utils/-/utils-8.3.0.tgz",
+      "integrity": "sha512-F77WwqxIi/qGkIGOGXNBLV7nykwfjLsdauRB/DOFPdv6LTF3BHHkBpq81/b5iMPSF055oO2BiivDJV4ChvNtXA==",
      "dev": true,
      "license": "MIT",
      "dependencies": {
        "@eslint-community/eslint-utils": "^4.4.0",
-        "@typescript-eslint/scope-manager": "8.4.0",
-        "@typescript-eslint/types": "8.4.0",
-        "@typescript-eslint/typescript-estree": "8.4.0"
+        "@typescript-eslint/scope-manager": "8.3.0",
+        "@typescript-eslint/types": "8.3.0",
+        "@typescript-eslint/typescript-estree": "8.3.0"
      },
      "engines": {
        "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1344,13 +1336,13 @@
      }
    },
    "node_modules/@typescript-eslint/visitor-keys": {
-      "version": "8.4.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/visitor-keys/-/visitor-keys-8.4.0.tgz",
-      "integrity": "sha512-zTQD6WLNTre1hj5wp09nBIDiOc2U5r/qmzo7wxPn4ZgAjHql09EofqhF9WF+fZHzL5aCyaIpPcT2hyxl73kr9A==",
+      "version": "8.3.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/visitor-keys/-/visitor-keys-8.3.0.tgz",
+      "integrity": "sha512-RmZwrTbQ9QveF15m/Cl28n0LXD6ea2CjkhH5rQ55ewz3H24w+AMCJHPVYaZ8/0HoG8Z3cLLFFycRXxeO2tz9FA==",
      "dev": true,
      "license": "MIT",
      "dependencies": {
-        "@typescript-eslint/types": "8.4.0",
+        "@typescript-eslint/types": "8.3.0",
        "eslint-visitor-keys": "^3.4.3"
      },
      "engines": {
@@ -2394,11 +2386,10 @@
      }
    },
    "node_modules/eslint-module-utils": {
-      "version": "2.11.0",
-      "resolved": "https://registry.npmjs.org/eslint-module-utils/-/eslint-module-utils-2.11.0.tgz",
-      "integrity": "sha512-gbBE5Hitek/oG6MUVj6sFuzEjA/ClzNflVrLovHi/JgLdC7fiN5gLAY1WIPW1a0V5I999MnsrvVrCOGmmVqDBQ==",
+      "version": "2.8.0",
+      "resolved": "https://registry.npmjs.org/eslint-module-utils/-/eslint-module-utils-2.8.0.tgz",
+      "integrity": "sha512-aWajIYfsqCKRDgUfjEXNN/JlrzauMuSEy5sbd7WXbtW3EH6A6MpwEh42c7qD+MqQo9QMJ6fWLAeIJynx0g6OAw==",
      "dev": true,
-      "license": "MIT",
      "dependencies": {
        "debug": "^3.2.7"
      },
@@ -2421,28 +2412,26 @@
      }
    },
    "node_modules/eslint-plugin-import": {
-      "version": "2.30.0",
-      "resolved": "https://registry.npmjs.org/eslint-plugin-import/-/eslint-plugin-import-2.30.0.tgz",
-      "integrity": "sha512-/mHNE9jINJfiD2EKkg1BKyPyUk4zdnT54YgbOgfjSakWT5oyX/qQLVNTkehyfpcMxZXMy1zyonZ2v7hZTX43Yw==",
+      "version": "2.29.1",
+      "resolved": "https://registry.npmjs.org/eslint-plugin-import/-/eslint-plugin-import-2.29.1.tgz",
+      "integrity": "sha512-BbPC0cuExzhiMo4Ff1BTVwHpjjv28C5R+btTOGaCRC7UEz801up0JadwkeSk5Ued6TG34uaczuVuH6qyy5YUxw==",
      "dev": true,
-      "license": "MIT",
      "dependencies": {
-        "@rtsao/scc": "^1.1.0",
-        "array-includes": "^3.1.8",
-        "array.prototype.findlastindex": "^1.2.5",
+        "array-includes": "^3.1.7",
+        "array.prototype.findlastindex": "^1.2.3",
        "array.prototype.flat": "^1.3.2",
        "array.prototype.flatmap": "^1.3.2",
        "debug": "^3.2.7",
        "doctrine": "^2.1.0",
        "eslint-import-resolver-node": "^0.3.9",
-        "eslint-module-utils": "^2.9.0",
-        "hasown": "^2.0.2",
-        "is-core-module": "^2.15.1",
+        "eslint-module-utils": "^2.8.0",
+        "hasown": "^2.0.0",
+        "is-core-module": "^2.13.1",
        "is-glob": "^4.0.3",
        "minimatch": "^3.1.2",
-        "object.fromentries": "^2.0.8",
-        "object.groupby": "^1.0.3",
-        "object.values": "^1.2.0",
+        "object.fromentries": "^2.0.7",
+        "object.groupby": "^1.0.1",
+        "object.values": "^1.1.7",
        "semver": "^6.3.1",
        "tsconfig-paths": "^3.15.0"
      },
@@ -2458,7 +2447,6 @@
      "resolved": "https://registry.npmjs.org/debug/-/debug-3.2.7.tgz",
      "integrity": "sha512-CFjzYYAi4ThfiQvizrFQevTTXHtnCqWfe7x1AhgEscTz6ZbLbfoLRLPugTQyBth6f8ZERVUSyWHFD/7Wu4t1XQ==",
      "dev": true,
-      "license": "MIT",
      "dependencies": {
        "ms": "^2.1.1"
      }
@@ -2468,7 +2456,6 @@
      "resolved": "https://registry.npmjs.org/doctrine/-/doctrine-2.1.0.tgz",
      "integrity": "sha512-35mSku4ZXK0vfCuHEDAwt55dg2jNajHZ1odvF+8SSr82EsZY4QmXfuWso8oEd8zRhVObSN18aM0CjSdoBX7zIw==",
      "dev": true,
-      "license": "Apache-2.0",
      "dependencies": {
        "esutils": "^2.0.2"
      },
@@ -2481,15 +2468,14 @@
      "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.1.tgz",
      "integrity": "sha512-BR7VvDCVHO+q2xBEWskxS6DJE1qRnb7DxzUrogb71CWoSficBxYsiAGd+Kl0mmq/MprG9yArRkyrQxTO6XjMzA==",
      "dev": true,
-      "license": "ISC",
      "bin": {
        "semver": "bin/semver.js"
      }
    },
    "node_modules/eslint-plugin-react": {
-      "version": "7.35.2",
-      "resolved": "https://registry.npmjs.org/eslint-plugin-react/-/eslint-plugin-react-7.35.2.tgz",
-      "integrity": "sha512-Rbj2R9zwP2GYNcIak4xoAMV57hrBh3hTaR0k7hVjwCQgryE/pw5px4b13EYjduOI0hfXyZhwBxaGpOTbWSGzKQ==",
+      "version": "7.35.0",
+      "resolved": "https://registry.npmjs.org/eslint-plugin-react/-/eslint-plugin-react-7.35.0.tgz",
+      "integrity": "sha512-v501SSMOWv8gerHkk+IIQBkcGRGrO2nfybfj5pLxuJNFTPxxA3PSryhXTK+9pNbtkggheDdsC0E9Q8CuPk6JKA==",
      "dev": true,
      "license": "MIT",
      "dependencies": {
@@ -3198,16 +3184,12 @@
      }
    },
    "node_modules/is-core-module": {
-      "version": "2.15.1",
-      "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.15.1.tgz",
-      "integrity": "sha512-z0vtXSwucUJtANQWldhbtbt7BnL0vxiFjIdDLAatwhDYty2bad6s+rijD6Ri4YuYJubLzIJLUidCh09e1djEVQ==",
+      "version": "2.13.1",
+      "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.13.1.tgz",
+      "integrity": "sha512-hHrIjvZsftOsvKSn2TRYl63zvxsgE0K+0mYMoH6gD4omR5IWB2KynivBQczo3+wF1cCkjzvptnI9Q0sPU66ilw==",
      "dev": true,
-      "license": "MIT",
      "dependencies": {
-        "hasown": "^2.0.2"
-      },
-      "engines": {
-        "node": ">= 0.4"
+        "hasown": "^2.0.0"
      },
      "funding": {
        "url": "https://github.com/sponsors/ljharb"
@@ -4029,9 +4011,9 @@
      }
    },
    "node_modules/postcss": {
-      "version": "8.4.45",
-      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.45.tgz",
-      "integrity": "sha512-7KTLTdzdZZYscUc65XmjFiB73vBhBfbPztCYdUNvlaso9PrzjzcmjqBPR0lNGkcVlcO4BjiO5rK/qNz+XAen1Q==",
+      "version": "8.4.43",
+      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.4.43.tgz",
+      "integrity": "sha512-gJAQVYbh5R3gYm33FijzCZj7CHyQ3hWMgJMprLUlIYqCwTeZhBQ19wp0e9mA25BUbEvY5+EXuuaAjqQsrBxQBQ==",
      "dev": true,
      "funding": [
        {
@@ -4561,18 +4543,6 @@
        "url": "https://github.com/sponsors/ljharb"
      }
    },
-    "node_modules/smol-toml": {
-      "version": "1.3.0",
-      "resolved": "https://registry.npmjs.org/smol-toml/-/smol-toml-1.3.0.tgz",
-      "integrity": "sha512-tWpi2TsODPScmi48b/OQZGi2lgUmBCHy6SZrhi/FdnnHiU1GwebbCfuQuxsC3nHaLwtYeJGPrDZDIeodDOc4pA==",
-      "license": "BSD-3-Clause",
-      "engines": {
-        "node": ">= 18"
-      },
-      "funding": {
-        "url": "https://github.com/sponsors/cyyynthia"
-      }
-    },
    "node_modules/source-map-js": {
      "version": "1.2.0",
      "resolved": "https://registry.npmjs.org/source-map-js/-/source-map-js-1.2.0.tgz",
@@ -5052,14 +5022,14 @@
      "dev": true
    },
    "node_modules/vite": {
-      "version": "5.4.3",
-      "resolved": "https://registry.npmjs.org/vite/-/vite-5.4.3.tgz",
-      "integrity": "sha512-IH+nl64eq9lJjFqU+/yrRnrHPVTlgy42/+IzbOdaFDVlyLgI/wDlf+FCobXLX1cT0X5+7LMyH1mIy2xJdLfo8Q==",
+      "version": "5.4.2",
+      "resolved": "https://registry.npmjs.org/vite/-/vite-5.4.2.tgz",
+      "integrity": "sha512-dDrQTRHp5C1fTFzcSaMxjk6vdpKvT+2/mIdE07Gw2ykehT49O0z/VHS3zZ8iV/Gh8BJJKHWOe5RjaNrW5xf/GA==",
      "dev": true,
      "license": "MIT",
      "dependencies": {
        "esbuild": "^0.21.3",
-        "postcss": "^8.4.43",
+        "postcss": "^8.4.41",
        "rollup": "^4.20.0"
      },
      "bin": {
--- a/playground/package.json
+++ b/playground/package.json
@@ -21,8 +21,7 @@
    "monaco-editor": "^0.51.0",
    "react": "^18.2.0",
    "react-dom": "^18.2.0",
-    "react-resizable-panels": "^2.0.0",
-    "smol-toml": "^1.3.0"
+    "react-resizable-panels": "^2.0.0"
  },
  "devDependencies": {
    "@types/react": "^18.0.26",
--- a/playground/src/Editor/SecondaryPanel.tsx
+++ b/playground/src/Editor/SecondaryPanel.tsx
@@ -1,4 +1,4 @@
-import MonacoEditor from "@monaco-editor/react";
+import Editor from "@monaco-editor/react";
 import { Theme } from "./theme";

 export enum SecondaryTool {
@@ -72,7 +72,7 @@ function Content({
        }

        return (
-          <MonacoEditor
+          <Editor
            options={{
              readOnly: true,
              minimap: { enabled: false },
--- a/playground/src/Editor/SettingsEditor.tsx
+++ b/playground/src/Editor/SettingsEditor.tsx
@@ -2,11 +2,10 @@
 * Editor for the settings JSON.
 */

-import { useCallback } from "react";
+import Editor, { useMonaco } from "@monaco-editor/react";
+import { useCallback, useEffect } from "react";
+import schema from "../../../ruff.schema.json";
 import { Theme } from "./theme";
-import MonacoEditor from "@monaco-editor/react";
-import { editor } from "monaco-editor";
-import IStandaloneCodeEditor = editor.IStandaloneCodeEditor;

 export default function SettingsEditor({
  visible,
@@ -19,147 +18,41 @@ export default function SettingsEditor({
  theme: Theme;
  onChange: (source: string) => void;
 }) {
+  const monaco = useMonaco();
+
+  useEffect(() => {
+    monaco?.languages.json.jsonDefaults.setDiagnosticsOptions({
+      schemas: [
+        {
+          uri: "https://raw.githubusercontent.com/astral-sh/ruff/main/ruff.schema.json",
+          fileMatch: ["*"],
+          schema,
+        },
+      ],
+    });
+  }, [monaco]);
+
  const handleChange = useCallback(
    (value: string | undefined) => {
      onChange(value ?? "");
    },
    [onChange],
  );
-
-  const handleMount = useCallback((editor: IStandaloneCodeEditor) => {
-    editor.addAction({
-      id: "copyAsRuffToml",
-      label: "Copy as ruff.toml",
-      contextMenuGroupId: "9_cutcopypaste",
-      contextMenuOrder: 3,
-
-      async run(editor): Promise<undefined> {
-        const model = editor.getModel();
-
-        if (model == null) {
-          return;
-        }
-
-        const toml = await import("smol-toml");
-        const settings = model.getValue();
-        const tomlSettings = toml.stringify(JSON.parse(settings));
-
-        await navigator.clipboard.writeText(tomlSettings);
-      },
-    });
-
-    editor.addAction({
-      id: "copyAsPyproject.toml",
-      label: "Copy as pyproject.toml",
-      contextMenuGroupId: "9_cutcopypaste",
-      contextMenuOrder: 4,
-
-      async run(editor): Promise<undefined> {
-        const model = editor.getModel();
-
-        if (model == null) {
-          return;
-        }
-
-        const settings = model.getValue();
-        const toml = await import("smol-toml");
-        const tomlSettings = toml.stringify(
-          prefixWithRuffToml(JSON.parse(settings)),
-        );
-
-        await navigator.clipboard.writeText(tomlSettings);
-      },
-    });
-    editor.onDidPaste((event) => {
-      const model = editor.getModel();
-
-      if (model == null) {
-        return;
-      }
-
-      // Allow pasting a TOML settings configuration if it replaces the entire settings.
-      if (model.getFullModelRange().equalsRange(event.range)) {
-        const pasted = model.getValueInRange(event.range);
-
-        // Text starting with a `{` must be JSON. Don't even try to parse as TOML.
-        if (!pasted.trimStart().startsWith("{")) {
-          import("smol-toml").then((toml) => {
-            try {
-              const parsed = toml.parse(pasted);
-              const cleansed = stripToolRuff(parsed);
-
-              model.setValue(JSON.stringify(cleansed, null, 4));
-            } catch (e) {
-              // Turned out to not be TOML after all.
-              console.warn("Failed to parse settings as TOML", e);
-            }
-          });
-        }
-      }
-    });
-  }, []);
-
  return (
-    <MonacoEditor
+    <Editor
      options={{
        readOnly: false,
        minimap: { enabled: false },
        fontSize: 14,
        roundedSelection: false,
        scrollBeyondLastLine: false,
-        contextmenu: true,
+        contextmenu: false,
      }}
-      onMount={handleMount}
      wrapperProps={visible ? {} : { style: { display: "none" } }}
-      language="json"
+      language={"json"}
      value={source}
      theme={theme === "light" ? "Ayu-Light" : "Ayu-Dark"}
      onChange={handleChange}
    />
  );
 }
-
-function stripToolRuff(settings: object) {
-  const { tool, ...nonToolSettings } = settings as any;
-
-  // Flatten out `tool.ruff.x` to just `x`
-  if (typeof tool == "object" && !Array.isArray(tool)) {
-    if (tool.ruff != null) {
-      return { ...nonToolSettings, ...tool.ruff };
-    }
-  }
-
-  return Object.fromEntries(
-    Object.entries(settings).flatMap(([key, value]) => {
-      if (key.startsWith("tool.ruff")) {
-        const strippedKey = key.substring("tool.ruff".length);
-
-        if (strippedKey === "") {
-          return Object.entries(value);
-        }
-
-        return [[strippedKey.substring(1), value]];
-      }
-
-      return [[key, value]];
-    }),
-  );
-}
-
-function prefixWithRuffToml(settings: object) {
-  const subTableEntries = [];
-  const ruffTableEntries = [];
-
-  for (const [key, value] of Object.entries(settings)) {
-    if (typeof value === "object" && !Array.isArray(value)) {
-      subTableEntries.push([`tool.ruff.${key}`, value]);
-    } else {
-      ruffTableEntries.push([key, value]);
-    }
-  }
-
-  return {
-    ["tool.ruff"]: Object.fromEntries(ruffTableEntries),
-    ...Object.fromEntries(subTableEntries),
-  };
-}
--- a/playground/src/Editor/SourceEditor.tsx
+++ b/playground/src/Editor/SourceEditor.tsx
@@ -2,25 +2,11 @@
 * Editor for the Python source code.
 */

-import MonacoEditor, { Monaco, OnMount } from "@monaco-editor/react";
-import {
-  editor,
-  IDisposable,
-  languages,
-  MarkerSeverity,
-  MarkerTag,
-  Range,
-} from "monaco-editor";
+import Editor, { BeforeMount, Monaco } from "@monaco-editor/react";
+import { MarkerSeverity, MarkerTag } from "monaco-editor";
 import { useCallback, useEffect, useRef } from "react";
 import { Diagnostic } from "../pkg";
 import { Theme } from "./theme";
-import CodeActionProvider = languages.CodeActionProvider;
-
-type MonacoEditorState = {
-  monaco: Monaco;
-  codeActionProvider: RuffCodeActionProvider;
-  disposeCodeActionProvider: IDisposable;
-};

 export default function SourceEditor({
  visible,
@@ -35,32 +21,80 @@ export default function SourceEditor({
  theme: Theme;
  onChange: (pythonSource: string) => void;
 }) {
-  const monacoRef = useRef<MonacoEditorState | null>(null);
+  const monacoRef = useRef<Monaco | null>(null);
+  const monaco = monacoRef.current;

-  // Update the diagnostics in the editor.
  useEffect(() => {
-    const editorState = monacoRef.current;
-
-    if (editorState == null) {
+    const editor = monaco?.editor;
+    const model = editor?.getModels()[0];
+    if (!editor || !model) {
      return;
    }

-    editorState.codeActionProvider.diagnostics = diagnostics;
+    editor.setModelMarkers(
+      model,
+      "owner",
+      diagnostics.map((diagnostic) => ({
+        startLineNumber: diagnostic.location.row,
+        startColumn: diagnostic.location.column,
+        endLineNumber: diagnostic.end_location.row,
+        endColumn: diagnostic.end_location.column,
+        message: diagnostic.code
+          ? `${diagnostic.code}: ${diagnostic.message}`
+          : diagnostic.message,
+        severity: MarkerSeverity.Error,
+        tags:
+          diagnostic.code === "F401" || diagnostic.code === "F841"
+            ? [MarkerTag.Unnecessary]
+            : [],
+      })),
+    );

-    updateMarkers(editorState.monaco, diagnostics);
-  }, [diagnostics]);
-
-  // Dispose the code action provider on unmount.
-  useEffect(() => {
-    const disposeActionProvider = monacoRef.current?.disposeCodeActionProvider;
-    if (disposeActionProvider == null) {
-      return;
-    }
+    const codeActionProvider = monaco?.languages.registerCodeActionProvider(
+      "python",
+      {
+        provideCodeActions: function (model, position) {
+          const actions = diagnostics
+            .filter((check) => position.startLineNumber === check.location.row)
+            .filter(({ fix }) => fix)
+            .map((check) => ({
+              title: check.fix
+                ? check.fix.message
+                  ? `${check.code}: ${check.fix.message}`
+                  : `Fix ${check.code}`
+                : "Fix",
+              id: `fix-${check.code}`,
+              kind: "quickfix",
+              edit: check.fix
+                ? {
+                    edits: check.fix.edits.map((edit) => ({
+                      resource: model.uri,
+                      versionId: model.getVersionId(),
+                      textEdit: {
+                        range: {
+                          startLineNumber: edit.location.row,
+                          startColumn: edit.location.column,
+                          endLineNumber: edit.end_location.row,
+                          endColumn: edit.end_location.column,
+                        },
+                        text: edit.content || "",
+                      },
+                    })),
+                  }
+                : undefined,
+            }));
+          return {
+            actions,
+            dispose: () => {},
+          };
+        },
+      },
+    );

    return () => {
-      disposeActionProvider.dispose();
+      codeActionProvider?.dispose();
    };
-  }, []);
+  }, [diagnostics, monaco]);

  const handleChange = useCallback(
    (value: string | undefined) => {
@@ -69,30 +103,14 @@ export default function SourceEditor({
    [onChange],
  );

-  const handleMount: OnMount = useCallback(
-    (_editor, instance) => {
-      const ruffActionsProvider = new RuffCodeActionProvider(diagnostics);
-      const disposeCodeActionProvider =
-        instance.languages.registerCodeActionProvider(
-          "python",
-          ruffActionsProvider,
-        );
-
-      updateMarkers(instance, diagnostics);
-
-      monacoRef.current = {
-        monaco: instance,
-        codeActionProvider: ruffActionsProvider,
-        disposeCodeActionProvider,
-      };
-    },
-
-    [diagnostics],
+  const handleMount: BeforeMount = useCallback(
+    (instance) => (monacoRef.current = instance),
+    [],
  );

  return (
-    <MonacoEditor
-      onMount={handleMount}
+    <Editor
+      beforeMount={handleMount}
      options={{
        fixedOverflowWidgets: true,
        readOnly: false,
@@ -110,76 +128,3 @@ export default function SourceEditor({
    />
  );
 }
-
-class RuffCodeActionProvider implements CodeActionProvider {
-  constructor(public diagnostics: Array<Diagnostic>) {}
-
-  provideCodeActions(
-    model: editor.ITextModel,
-    range: Range,
-  ): languages.ProviderResult<languages.CodeActionList> {
-    const actions = this.diagnostics
-      .filter((check) => range.startLineNumber === check.location.row)
-      .filter(({ fix }) => fix)
-      .map((check) => ({
-        title: check.fix
-          ? check.fix.message
-            ? `${check.code}: ${check.fix.message}`
-            : `Fix ${check.code}`
-          : "Fix",
-        id: `fix-${check.code}`,
-        kind: "quickfix",
-
-        edit: check.fix
-          ? {
-              edits: check.fix.edits.map((edit) => ({
-                resource: model.uri,
-                versionId: model.getVersionId(),
-                textEdit: {
-                  range: {
-                    startLineNumber: edit.location.row,
-                    startColumn: edit.location.column,
-                    endLineNumber: edit.end_location.row,
-                    endColumn: edit.end_location.column,
-                  },
-                  text: edit.content || "",
-                },
-              })),
-            }
-          : undefined,
-      }));
-
-    return {
-      actions,
-      dispose: () => {},
-    };
-  }
-}
-
-function updateMarkers(monaco: Monaco, diagnostics: Array<Diagnostic>) {
-  const editor = monaco.editor;
-  const model = editor?.getModels()[0];
-
-  if (!model) {
-    return;
-  }
-
-  editor.setModelMarkers(
-    model,
-    "owner",
-    diagnostics.map((diagnostic) => ({
-      startLineNumber: diagnostic.location.row,
-      startColumn: diagnostic.location.column,
-      endLineNumber: diagnostic.end_location.row,
-      endColumn: diagnostic.end_location.column,
-      message: diagnostic.code
-        ? `${diagnostic.code}: ${diagnostic.message}`
-        : diagnostic.message,
-      severity: MarkerSeverity.Error,
-      tags:
-        diagnostic.code === "F401" || diagnostic.code === "F841"
-          ? [MarkerTag.Unnecessary]
-          : [],
-    })),
-  );
-}
--- a/playground/src/Editor/setupMonaco.tsx
+++ b/playground/src/Editor/setupMonaco.tsx
@@ -3,7 +3,6 @@
 */

 import { Monaco } from "@monaco-editor/react";
-import schema from "../../../ruff.schema.json";

 export const WHITE = "#ffffff";
 export const RADIATE = "#d7ff64";
@@ -32,16 +31,6 @@ export function setupMonaco(monaco: Monaco) {
  defineRustPythonTokensLanguage(monaco);
  defineRustPythonAstLanguage(monaco);
  defineCommentsLanguage(monaco);
-
-  monaco.languages.json.jsonDefaults.setDiagnosticsOptions({
-    schemas: [
-      {
-        uri: "https://raw.githubusercontent.com/astral-sh/ruff/main/ruff.schema.json",
-        fileMatch: ["*"],
-        schema,
-      },
-    ],
-  });
 }

 function defineAyuThemes(monaco: Monaco) {
--- a/Show More
+++ b/Show More