preview->stable

Feel free to complain about the rephrasing in the docs!

CHANGELOG.md

@@ -1,5 +1,31 @@
 # Changelog
 
+## 0.11.13
+
+### Preview features
+
+- \[`airflow`\] Add unsafe fix for module moved cases (`AIR301`,`AIR311`,`AIR312`,`AIR302`) ([#18367](https://github.com/astral-sh/ruff/pull/18367),[#18366](https://github.com/astral-sh/ruff/pull/18366),[#18363](https://github.com/astral-sh/ruff/pull/18363),[#18093](https://github.com/astral-sh/ruff/pull/18093))
+- \[`refurb`\] Add coverage of `set` and `frozenset` calls (`FURB171`) ([#18035](https://github.com/astral-sh/ruff/pull/18035))
+- \[`refurb`\] Mark `FURB180` fix unsafe when class has bases ([#18149](https://github.com/astral-sh/ruff/pull/18149))
+
+### Bug fixes
+
+- \[`perflint`\] Fix missing parentheses for lambda and ternary conditions (`PERF401`, `PERF403`) ([#18412](https://github.com/astral-sh/ruff/pull/18412))
+- \[`pyupgrade`\] Apply `UP035` only on py313+ for `get_type_hints()` ([#18476](https://github.com/astral-sh/ruff/pull/18476))
+- \[`pyupgrade`\] Make fix unsafe if it deletes comments (`UP004`,`UP050`) ([#18393](https://github.com/astral-sh/ruff/pull/18393), [#18390](https://github.com/astral-sh/ruff/pull/18390))
+
+### Rule changes
+
+- \[`fastapi`\] Avoid false positive for class dependencies (`FAST003`) ([#18271](https://github.com/astral-sh/ruff/pull/18271))
+
+### Documentation
+
+- Update editor setup docs for Neovim and Vim ([#18324](https://github.com/astral-sh/ruff/pull/18324))
+
+### Other changes
+
+- Support Python 3.14 template strings (t-strings) in formatter and parser ([#17851](https://github.com/astral-sh/ruff/pull/17851))
+
 ## 0.11.12
 
 ### Preview features

Cargo.lock

@@ -2501,7 +2501,7 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.11.12"
+version = "0.11.13"
 dependencies = [
  "anyhow",
  "argfile",
@@ -2738,7 +2738,7 @@ dependencies = [
 
 [[package]]
 name = "ruff_linter"
-version = "0.11.12"
+version = "0.11.13"
 dependencies = [
  "aho-corasick",
  "anyhow",
@@ -3074,7 +3074,7 @@ dependencies = [
 
 [[package]]
 name = "ruff_wasm"
-version = "0.11.12"
+version = "0.11.13"
 dependencies = [
  "console_error_panic_hook",
  "console_log",
@@ -3965,6 +3965,7 @@ dependencies = [
  "anyhow",
  "bitflags 2.9.1",
  "camino",
+ "colored 3.0.0",
  "compact_str",
  "countme",
  "dir-test",
@@ -3977,6 +3978,7 @@ dependencies = [
  "ordermap",
  "quickcheck",
  "quickcheck_macros",
+ "ruff_annotate_snippets",
  "ruff_db",
  "ruff_index",
  "ruff_macros",

README.md

@@ -148,8 +148,8 @@ 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/0.11.12/install.sh | sh
-powershell -c "irm https://astral.sh/ruff/0.11.12/install.ps1 | iex"
+curl -LsSf https://astral.sh/ruff/0.11.13/install.sh | sh
+powershell -c "irm https://astral.sh/ruff/0.11.13/install.ps1 | iex"
 ```
 
 You can also install Ruff via [Homebrew](https://formulae.brew.sh/formula/ruff), [Conda](https://anaconda.org/conda-forge/ruff),
@@ -182,7 +182,7 @@ 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: v0.11.12
+  rev: v0.11.13
   hooks:
     # Run the linter.
     - id: ruff

crates/ruff/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff"
-version = "0.11.12"
+version = "0.11.13"
 publish = true
 authors = { workspace = true }
 edition = { workspace = true }

crates/ruff/src/cache.rs

@@ -439,7 +439,10 @@ impl LintCacheData {
 
         let messages = messages
             .iter()
-            .filter_map(|msg| msg.to_rule().map(|rule| (rule, msg)))
+            // Parse the kebab-case rule name into a `Rule`. This will fail for syntax errors, so
+            // this also serves to filter them out, but we shouldn't be caching files with syntax
+            // errors anyway.
+            .filter_map(|msg| Some((msg.name().parse().ok()?, msg)))
             .map(|(rule, msg)| {
                 // Make sure that all message use the same source file.
                 assert_eq!(

crates/ruff/src/commands/rule.rs

@@ -30,7 +30,7 @@ impl<'a> Explanation<'a> {
         let (linter, _) = Linter::parse_code(&code).unwrap();
         let fix = rule.fixable().to_string();
         Self {
-            name: rule.as_ref(),
+            name: rule.name().as_str(),
             code,
             linter: linter.name(),
             summary: rule.message_formats()[0],
@@ -44,7 +44,7 @@ impl<'a> Explanation<'a> {
 
 fn format_rule_text(rule: Rule) -> String {
     let mut output = String::new();
-    let _ = write!(&mut output, "# {} ({})", rule.as_ref(), rule.noqa_code());
+    let _ = write!(&mut output, "# {} ({})", rule.name(), rule.noqa_code());
     output.push('\n');
     output.push('\n');
 

crates/ruff/src/diagnostics.rs

@@ -165,9 +165,9 @@ impl AddAssign for FixMap {
                 continue;
             }
             let fixed_in_file = self.0.entry(filename).or_default();
-            for (rule, count) in fixed {
+            for (rule, name, count) in fixed.iter() {
                 if count > 0 {
-                    *fixed_in_file.entry(rule).or_default() += count;
+                    *fixed_in_file.entry(rule).or_default(name) += count;
                 }
             }
         }
@@ -305,7 +305,7 @@ pub(crate) fn lint_path(
                     ParseSource::None,
                 );
                 let transformed = source_kind;
-                let fixed = FxHashMap::default();
+                let fixed = FixTable::default();
                 (result, transformed, fixed)
             }
         } else {
@@ -319,7 +319,7 @@ pub(crate) fn lint_path(
                 ParseSource::None,
             );
             let transformed = source_kind;
-            let fixed = FxHashMap::default();
+            let fixed = FixTable::default();
             (result, transformed, fixed)
         };
 
@@ -473,7 +473,7 @@ pub(crate) fn lint_stdin(
                 }
 
                 let transformed = source_kind;
-                let fixed = FxHashMap::default();
+                let fixed = FixTable::default();
                 (result, transformed, fixed)
             }
         } else {
@@ -487,7 +487,7 @@ pub(crate) fn lint_stdin(
                 ParseSource::None,
             );
             let transformed = source_kind;
-            let fixed = FxHashMap::default();
+            let fixed = FixTable::default();
             (result, transformed, fixed)
         };
 

crates/ruff/src/printer.rs

@@ -7,6 +7,7 @@ use bitflags::bitflags;
 use colored::Colorize;
 use itertools::{Itertools, iterate};
 use ruff_linter::codes::NoqaCode;
+use ruff_linter::linter::FixTable;
 use serde::Serialize;
 
 use ruff_linter::fs::relativize_path;
@@ -80,7 +81,7 @@ impl Printer {
             let fixed = diagnostics
                 .fixed
                 .values()
-                .flat_map(std::collections::HashMap::values)
+                .flat_map(FixTable::counts)
                 .sum::<usize>();
 
             if self.flags.intersects(Flags::SHOW_VIOLATIONS) {
@@ -302,7 +303,7 @@ impl Printer {
         let statistics: Vec<ExpandedStatistics> = diagnostics
             .messages
             .iter()
-            .map(|message| (message.to_noqa_code(), message))
+            .map(|message| (message.noqa_code(), message))
             .sorted_by_key(|(code, message)| (*code, message.fixable()))
             .fold(
                 vec![],
@@ -472,13 +473,13 @@ fn show_fix_status(fix_mode: flags::FixMode, fixables: Option<&FixableStatistics
 fn print_fix_summary(writer: &mut dyn Write, fixed: &FixMap) -> Result<()> {
     let total = fixed
         .values()
-        .map(|table| table.values().sum::<usize>())
+        .map(|table| table.counts().sum::<usize>())
         .sum::<usize>();
     assert!(total > 0);
     let num_digits = num_digits(
-        *fixed
+        fixed
             .values()
-            .filter_map(|table| table.values().max())
+            .filter_map(|table| table.counts().max())
             .max()
             .unwrap(),
     );
@@ -498,12 +499,11 @@ fn print_fix_summary(writer: &mut dyn Write, fixed: &FixMap) -> Result<()> {
             relativize_path(filename).bold(),
             ":".cyan()
         )?;
-        for (rule, count) in table.iter().sorted_by_key(|(.., count)| Reverse(*count)) {
+        for (code, name, count) in table.iter().sorted_by_key(|(.., count)| Reverse(*count)) {
             writeln!(
                 writer,
-                "    {count:>num_digits$} × {} ({})",
-                rule.noqa_code().to_string().red().bold(),
-                rule.as_ref(),
+                "    {count:>num_digits$} × {code} ({name})",
+                code = code.to_string().red().bold(),
             )?;
         }
     }

crates/ruff/tests/analyze_graph.rs

@@ -566,7 +566,7 @@ fn venv() -> Result<()> {
         ----- stderr -----
         ruff failed
           Cause: Invalid search path settings
-          Cause: Failed to discover the site-packages directory: Invalid `--python` argument: `none` does not point to a Python executable or a directory on disk
+          Cause: Failed to discover the site-packages directory: Invalid `--python` argument `none`: does not point to a Python executable or a directory on disk
         ");
     });
 

crates/ruff/tests/lint.rs

@@ -5436,14 +5436,15 @@ match 2:
         print("it's one")
 "#
         ),
-        @r"
-    success: true
-    exit_code: 0
+        @r###"
+    success: false
+    exit_code: 1
     ----- stdout -----
-    All checks passed!
+    test.py:2:1: SyntaxError: Cannot use `match` statement on Python 3.9 (syntax was added in Python 3.10)
+    Found 1 error.
 
     ----- stderr -----
-    "
+    "###
     );
 
     // syntax error on 3.9 with preview

crates/ruff_db/src/parsed.rs

@@ -1,5 +1,4 @@
 use std::fmt::Formatter;
-use std::ops::Deref;
 use std::sync::Arc;
 
 use ruff_python_ast::ModModule;
@@ -18,7 +17,7 @@ use crate::source::source_text;
 /// The query is only cached when the [`source_text()`] hasn't changed. This is because
 /// comparing two ASTs is a non-trivial operation and every offset change is directly
 /// reflected in the changed AST offsets.
-/// The other reason is that Ruff's AST doesn't implement `Eq` which Sala requires
+/// The other reason is that Ruff's AST doesn't implement `Eq` which Salsa requires
 /// for determining if a query result is unchanged.
 #[salsa::tracked(returns(ref), no_eq)]
 pub fn parsed_module(db: &dyn Db, file: File) -> ParsedModule {
@@ -36,7 +35,10 @@ pub fn parsed_module(db: &dyn Db, file: File) -> ParsedModule {
     ParsedModule::new(parsed)
 }
 
-/// Cheap cloneable wrapper around the parsed module.
+/// A wrapper around a parsed module.
+///
+/// This type manages instances of the module AST. A particular instance of the AST
+/// is represented with the [`ParsedModuleRef`] type.
 #[derive(Clone)]
 pub struct ParsedModule {
     inner: Arc<Parsed<ModModule>>,
@@ -49,17 +51,11 @@ impl ParsedModule {
         }
     }
 
-    /// Consumes `self` and returns the Arc storing the parsed module.
-    pub fn into_arc(self) -> Arc<Parsed<ModModule>> {
-        self.inner
-    }
-}
-
-impl Deref for ParsedModule {
-    type Target = Parsed<ModModule>;
-
-    fn deref(&self) -> &Self::Target {
-        &self.inner
+    /// Loads a reference to the parsed module.
+    pub fn load(&self, _db: &dyn Db) -> ParsedModuleRef {
+        ParsedModuleRef {
+            module_ref: self.inner.clone(),
+        }
     }
 }
 
@@ -77,6 +73,30 @@ impl PartialEq for ParsedModule {
 
 impl Eq for ParsedModule {}
 
+/// Cheap cloneable wrapper around an instance of a module AST.
+#[derive(Clone)]
+pub struct ParsedModuleRef {
+    module_ref: Arc<Parsed<ModModule>>,
+}
+
+impl ParsedModuleRef {
+    pub fn as_arc(&self) -> &Arc<Parsed<ModModule>> {
+        &self.module_ref
+    }
+
+    pub fn into_arc(self) -> Arc<Parsed<ModModule>> {
+        self.module_ref
+    }
+}
+
+impl std::ops::Deref for ParsedModuleRef {
+    type Target = Parsed<ModModule>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.module_ref
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use crate::Db;
@@ -98,7 +118,7 @@ mod tests {
 
         let file = system_path_to_file(&db, path).unwrap();
 
-        let parsed = parsed_module(&db, file);
+        let parsed = parsed_module(&db, file).load(&db);
 
         assert!(parsed.has_valid_syntax());
 
@@ -114,7 +134,7 @@ mod tests {
 
         let file = system_path_to_file(&db, path).unwrap();
 
-        let parsed = parsed_module(&db, file);
+        let parsed = parsed_module(&db, file).load(&db);
 
         assert!(parsed.has_valid_syntax());
 
@@ -130,7 +150,7 @@ mod tests {
 
         let virtual_file = db.files().virtual_file(&db, path);
 
-        let parsed = parsed_module(&db, virtual_file.file());
+        let parsed = parsed_module(&db, virtual_file.file()).load(&db);
 
         assert!(parsed.has_valid_syntax());
 
@@ -146,7 +166,7 @@ mod tests {
 
         let virtual_file = db.files().virtual_file(&db, path);
 
-        let parsed = parsed_module(&db, virtual_file.file());
+        let parsed = parsed_module(&db, virtual_file.file()).load(&db);
 
         assert!(parsed.has_valid_syntax());
 
@@ -177,7 +197,7 @@ else:
 
         let file = vendored_path_to_file(&db, VendoredPath::new("path.pyi")).unwrap();
 
-        let parsed = parsed_module(&db, file);
+        let parsed = parsed_module(&db, file).load(&db);
 
         assert!(parsed.has_valid_syntax());
     }

crates/ruff_db/src/system.rs

@@ -171,6 +171,21 @@ pub trait System: Debug {
         PatternError,
     >;
 
+    /// Fetches the environment variable `key` from the current process.
+    ///
+    /// # Errors
+    ///
+    /// Returns [`std::env::VarError::NotPresent`] if:
+    /// - The variable is not set.
+    /// - The variable's name contains an equal sign or NUL (`'='` or `'\0'`).
+    ///
+    /// Returns [`std::env::VarError::NotUnicode`] if the variable's value is not valid
+    /// Unicode.
+    fn env_var(&self, name: &str) -> std::result::Result<String, std::env::VarError> {
+        let _ = name;
+        Err(std::env::VarError::NotPresent)
+    }
+
     fn as_any(&self) -> &dyn std::any::Any;
 
     fn as_any_mut(&mut self) -> &mut dyn std::any::Any;

crates/ruff_db/src/system/os.rs

@@ -214,6 +214,10 @@ impl System for OsSystem {
             })
         })))
     }
+
+    fn env_var(&self, name: &str) -> std::result::Result<String, std::env::VarError> {
+        std::env::var(name)
+    }
 }
 
 impl OsSystem {

crates/ruff_dev/src/generate_docs.rs

@@ -29,7 +29,7 @@ pub(crate) fn main(args: &Args) -> Result<()> {
         if let Some(explanation) = rule.explanation() {
             let mut output = String::new();
 
-            let _ = writeln!(&mut output, "# {} ({})", rule.as_ref(), rule.noqa_code());
+            let _ = writeln!(&mut output, "# {} ({})", rule.name(), rule.noqa_code());
 
             let (linter, _) = Linter::parse_code(&rule.noqa_code().to_string()).unwrap();
             if linter.url().is_some() {
@@ -101,7 +101,7 @@ pub(crate) fn main(args: &Args) -> Result<()> {
             let filename = PathBuf::from(ROOT_DIR)
                 .join("docs")
                 .join("rules")
-                .join(rule.as_ref())
+                .join(&*rule.name())
                 .with_extension("md");
 
             if args.dry_run {

crates/ruff_dev/src/generate_rules_table.rs

@@ -55,7 +55,7 @@ fn generate_table(table_out: &mut String, rules: impl IntoIterator<Item = Rule>,
             FixAvailability::None => format!("<span {SYMBOL_STYLE}></span>"),
         };
 
-        let rule_name = rule.as_ref();
+        let rule_name = rule.name();
 
         // If the message ends in a bracketed expression (like: "Use {replacement}"), escape the
         // brackets. Otherwise, it'll be interpreted as an HTML attribute via the `attr_list`

crates/ruff_linter/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff_linter"
-version = "0.11.12"
+version = "0.11.13"
 publish = false
 authors = { workspace = true }
 edition = { workspace = true }

crates/ruff_linter/resources/test/fixtures/pyupgrade/UP035.py

@@ -110,6 +110,8 @@ from typing_extensions import CapsuleType
 # UP035 on py313+ only
 from typing_extensions import deprecated
 
+# UP035 on py313+ only
+from typing_extensions import get_type_hints
 
 # https://github.com/astral-sh/ruff/issues/15780
 from typing_extensions import is_typeddict

crates/ruff_linter/resources/test/fixtures/refurb/FURB129.py

@@ -102,3 +102,6 @@ with open("furb129.py") as f:
         pass
     for line in(f).readlines():
         pass
+
+    # Test case for issue #17683 (missing space before keyword)
+    print([line for line in f.readlines()if True])

crates/ruff_linter/src/checkers/ast/mod.rs

@@ -65,7 +65,7 @@ use crate::docstrings::extraction::ExtractionTarget;
 use crate::importer::{ImportRequest, Importer, ResolutionError};
 use crate::noqa::NoqaMapping;
 use crate::package::PackageRoot;
-use crate::preview::{is_semantic_errors_enabled, is_undefined_export_in_dunder_init_enabled};
+use crate::preview::is_undefined_export_in_dunder_init_enabled;
 use crate::registry::{AsRule, Rule};
 use crate::rules::pyflakes::rules::{
     LateFutureImport, ReturnOutsideFunction, YieldOutsideFunction,
@@ -663,9 +663,7 @@ impl SemanticSyntaxContext for Checker<'_> {
             | SemanticSyntaxErrorKind::AsyncComprehensionInSyncComprehension(_)
             | SemanticSyntaxErrorKind::DuplicateParameter(_)
             | SemanticSyntaxErrorKind::NonlocalDeclarationAtModuleLevel => {
-                if is_semantic_errors_enabled(self.settings) {
-                    self.semantic_errors.borrow_mut().push(error);
-                }
+                self.semantic_errors.borrow_mut().push(error);
             }
         }
     }

crates/ruff_linter/src/checkers/noqa.rs

@@ -12,7 +12,6 @@ use crate::fix::edits::delete_comment;
 use crate::noqa::{
     Code, Directive, FileExemption, FileNoqaDirectives, NoqaDirectives, NoqaMapping,
 };
-use crate::preview::is_check_file_level_directives_enabled;
 use crate::registry::{AsRule, Rule, RuleSet};
 use crate::rule_redirects::get_redirect_target;
 use crate::rules::pygrep_hooks;
@@ -112,25 +111,16 @@ pub(crate) fn check_noqa(
         && !exemption.includes(Rule::UnusedNOQA)
         && !per_file_ignores.contains(Rule::UnusedNOQA)
     {
-        let directives: Vec<_> = if is_check_file_level_directives_enabled(settings) {
-            noqa_directives
-                .lines()
-                .iter()
-                .map(|line| (&line.directive, &line.matches, false))
-                .chain(
-                    file_noqa_directives
-                        .lines()
-                        .iter()
-                        .map(|line| (&line.parsed_file_exemption, &line.matches, true)),
-                )
-                .collect()
-        } else {
-            noqa_directives
-                .lines()
-                .iter()
-                .map(|line| (&line.directive, &line.matches, false))
-                .collect()
-        };
+        let directives = noqa_directives
+            .lines()
+            .iter()
+            .map(|line| (&line.directive, &line.matches, false))
+            .chain(
+                file_noqa_directives
+                    .lines()
+                    .iter()
+                    .map(|line| (&line.parsed_file_exemption, &line.matches, true)),
+            );
         for (directive, matches, is_file_level) in directives {
             match directive {
                 Directive::All(directive) => {

crates/ruff_linter/src/codes.rs

@@ -4,13 +4,13 @@
 /// `--select`. For pylint this is e.g. C0414 and E0118 but also C and E01.
 use std::fmt::Formatter;
 
-use strum_macros::{AsRefStr, EnumIter};
+use strum_macros::EnumIter;
 
 use crate::registry::Linter;
 use crate::rule_selector::is_single_rule_selector;
 use crate::rules;
 
-#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct NoqaCode(&'static str, &'static str);
 
 impl NoqaCode {
@@ -1019,13 +1019,13 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Ruff, "049") => (RuleGroup::Preview, rules::ruff::rules::DataclassEnum),
         (Ruff, "051") => (RuleGroup::Stable, rules::ruff::rules::IfKeyInDictDel),
         (Ruff, "052") => (RuleGroup::Preview, rules::ruff::rules::UsedDummyVariable),
-        (Ruff, "053") => (RuleGroup::Preview, rules::ruff::rules::ClassWithMixedTypeVars),
+        (Ruff, "053") => (RuleGroup::Stable, rules::ruff::rules::ClassWithMixedTypeVars),
         (Ruff, "054") => (RuleGroup::Preview, rules::ruff::rules::IndentedFormFeed),
         (Ruff, "055") => (RuleGroup::Preview, rules::ruff::rules::UnnecessaryRegularExpression),
         (Ruff, "056") => (RuleGroup::Preview, rules::ruff::rules::FalsyDictGetFallback),
         (Ruff, "057") => (RuleGroup::Preview, rules::ruff::rules::UnnecessaryRound),
         (Ruff, "058") => (RuleGroup::Preview, rules::ruff::rules::StarmapZip),
-        (Ruff, "059") => (RuleGroup::Stable, rules::ruff::rules::UnusedUnpackedVariable),
+        (Ruff, "059") => (RuleGroup::Preview, rules::ruff::rules::UnusedUnpackedVariable),
         (Ruff, "060") => (RuleGroup::Preview, rules::ruff::rules::InEmptyCollection),
         (Ruff, "100") => (RuleGroup::Stable, rules::ruff::rules::UnusedNOQA),
         (Ruff, "101") => (RuleGroup::Stable, rules::ruff::rules::RedirectedNOQA),
@@ -1121,7 +1121,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Refurb, "132") => (RuleGroup::Preview, rules::refurb::rules::CheckAndRemoveFromSet),
         (Refurb, "136") => (RuleGroup::Stable, rules::refurb::rules::IfExprMinMax),
         (Refurb, "140") => (RuleGroup::Preview, rules::refurb::rules::ReimplementedStarmap),
-        (Refurb, "142") => (RuleGroup::Preview, rules::refurb::rules::ForLoopSetMutations),
+        (Refurb, "142") => (RuleGroup::Stable, rules::refurb::rules::ForLoopSetMutations),
         (Refurb, "145") => (RuleGroup::Preview, rules::refurb::rules::SliceCopy),
         (Refurb, "148") => (RuleGroup::Preview, rules::refurb::rules::UnnecessaryEnumerate),
         (Refurb, "152") => (RuleGroup::Preview, rules::refurb::rules::MathConstant),
@@ -1129,7 +1129,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Refurb, "156") => (RuleGroup::Preview, rules::refurb::rules::HardcodedStringCharset),
         (Refurb, "157") => (RuleGroup::Preview, rules::refurb::rules::VerboseDecimalConstructor),
         (Refurb, "161") => (RuleGroup::Stable, rules::refurb::rules::BitCount),
-        (Refurb, "162") => (RuleGroup::Preview, rules::refurb::rules::FromisoformatReplaceZ),
+        (Refurb, "162") => (RuleGroup::Stable, rules::refurb::rules::FromisoformatReplaceZ),
         (Refurb, "163") => (RuleGroup::Stable, rules::refurb::rules::RedundantLogBase),
         (Refurb, "164") => (RuleGroup::Preview, rules::refurb::rules::UnnecessaryFromFloat),
         (Refurb, "166") => (RuleGroup::Preview, rules::refurb::rules::IntOnSlicedStr),

crates/ruff_linter/src/fix/mod.rs

@@ -1,7 +1,7 @@
 use std::collections::BTreeSet;
 
 use itertools::Itertools;
-use rustc_hash::{FxHashMap, FxHashSet};
+use rustc_hash::FxHashSet;
 
 use ruff_diagnostics::{IsolationLevel, SourceMap};
 use ruff_text_size::{Ranged, TextLen, TextRange, TextSize};
@@ -59,13 +59,13 @@ fn apply_fixes<'a>(
     let mut last_pos: Option<TextSize> = None;
     let mut applied: BTreeSet<&Edit> = BTreeSet::default();
     let mut isolated: FxHashSet<u32> = FxHashSet::default();
-    let mut fixed = FxHashMap::default();
+    let mut fixed = FixTable::default();
     let mut source_map = SourceMap::default();
 
-    for (rule, fix) in diagnostics
-        .filter_map(|msg| msg.to_rule().map(|rule| (rule, msg)))
-        .filter_map(|(rule, diagnostic)| diagnostic.fix().map(|fix| (rule, fix)))
-        .sorted_by(|(rule1, fix1), (rule2, fix2)| cmp_fix(*rule1, *rule2, fix1, fix2))
+    for (code, name, fix) in diagnostics
+        .filter_map(|msg| msg.noqa_code().map(|code| (code, msg.name(), msg)))
+        .filter_map(|(code, name, diagnostic)| diagnostic.fix().map(|fix| (code, name, fix)))
+        .sorted_by(|(_, name1, fix1), (_, name2, fix2)| cmp_fix(name1, name2, fix1, fix2))
     {
         let mut edits = fix
             .edits()
@@ -110,7 +110,7 @@ fn apply_fixes<'a>(
         }
 
         applied.extend(applied_edits.drain(..));
-        *fixed.entry(rule).or_default() += 1;
+        *fixed.entry(code).or_default(name) += 1;
     }
 
     // Add the remaining content.
@@ -125,34 +125,44 @@ fn apply_fixes<'a>(
 }
 
 /// Compare two fixes.
-fn cmp_fix(rule1: Rule, rule2: Rule, fix1: &Fix, fix2: &Fix) -> std::cmp::Ordering {
+fn cmp_fix(name1: &str, name2: &str, fix1: &Fix, fix2: &Fix) -> std::cmp::Ordering {
     // Always apply `RedefinedWhileUnused` before `UnusedImport`, as the latter can end up fixing
     // the former. But we can't apply this just for `RedefinedWhileUnused` and `UnusedImport` because it violates
     // `< is transitive: a < b and b < c implies a < c. The same must hold for both == and >.`
     // See https://github.com/astral-sh/ruff/issues/12469#issuecomment-2244392085
-    match (rule1, rule2) {
-        (Rule::RedefinedWhileUnused, Rule::RedefinedWhileUnused) => std::cmp::Ordering::Equal,
-        (Rule::RedefinedWhileUnused, _) => std::cmp::Ordering::Less,
-        (_, Rule::RedefinedWhileUnused) => std::cmp::Ordering::Greater,
-        _ => std::cmp::Ordering::Equal,
+    let redefined_while_unused = Rule::RedefinedWhileUnused.name().as_str();
+    if (name1, name2) == (redefined_while_unused, redefined_while_unused) {
+        std::cmp::Ordering::Equal
+    } else if name1 == redefined_while_unused {
+        std::cmp::Ordering::Less
+    } else if name2 == redefined_while_unused {
+        std::cmp::Ordering::Greater
+    } else {
+        std::cmp::Ordering::Equal
     }
     // Apply fixes in order of their start position.
     .then_with(|| fix1.min_start().cmp(&fix2.min_start()))
     // Break ties in the event of overlapping rules, for some specific combinations.
-    .then_with(|| match (&rule1, &rule2) {
+    .then_with(|| {
+        let rules = (name1, name2);
         // Apply `MissingTrailingPeriod` fixes before `NewLineAfterLastParagraph` fixes.
-        (Rule::MissingTrailingPeriod, Rule::NewLineAfterLastParagraph) => std::cmp::Ordering::Less,
-        (Rule::NewLineAfterLastParagraph, Rule::MissingTrailingPeriod) => {
+        let missing_trailing_period = Rule::MissingTrailingPeriod.name().as_str();
+        let newline_after_last_paragraph = Rule::NewLineAfterLastParagraph.name().as_str();
+        let if_else_instead_of_dict_get = Rule::IfElseBlockInsteadOfDictGet.name().as_str();
+        let if_else_instead_of_if_exp = Rule::IfElseBlockInsteadOfIfExp.name().as_str();
+        if rules == (missing_trailing_period, newline_after_last_paragraph) {
+            std::cmp::Ordering::Less
+        } else if rules == (newline_after_last_paragraph, missing_trailing_period) {
             std::cmp::Ordering::Greater
         }
         // Apply `IfElseBlockInsteadOfDictGet` fixes before `IfElseBlockInsteadOfIfExp` fixes.
-        (Rule::IfElseBlockInsteadOfDictGet, Rule::IfElseBlockInsteadOfIfExp) => {
+        else if rules == (if_else_instead_of_dict_get, if_else_instead_of_if_exp) {
             std::cmp::Ordering::Less
-        }
-        (Rule::IfElseBlockInsteadOfIfExp, Rule::IfElseBlockInsteadOfDictGet) => {
+        } else if rules == (if_else_instead_of_if_exp, if_else_instead_of_dict_get) {
             std::cmp::Ordering::Greater
+        } else {
+            std::cmp::Ordering::Equal
         }
-        _ => std::cmp::Ordering::Equal,
     })
 }
 
@@ -197,7 +207,7 @@ mod tests {
             source_map,
         } = apply_fixes(diagnostics.iter(), &locator);
         assert_eq!(code, "");
-        assert_eq!(fixes.values().sum::<usize>(), 0);
+        assert_eq!(fixes.counts().sum::<usize>(), 0);
         assert!(source_map.markers().is_empty());
     }
 
@@ -234,7 +244,7 @@ print("hello world")
 "#
             .trim()
         );
-        assert_eq!(fixes.values().sum::<usize>(), 1);
+        assert_eq!(fixes.counts().sum::<usize>(), 1);
         assert_eq!(
             source_map.markers(),
             &[
@@ -275,7 +285,7 @@ class A(Bar):
 "
             .trim(),
         );
-        assert_eq!(fixes.values().sum::<usize>(), 1);
+        assert_eq!(fixes.counts().sum::<usize>(), 1);
         assert_eq!(
             source_map.markers(),
             &[
@@ -312,7 +322,7 @@ class A:
 "
             .trim()
         );
-        assert_eq!(fixes.values().sum::<usize>(), 1);
+        assert_eq!(fixes.counts().sum::<usize>(), 1);
         assert_eq!(
             source_map.markers(),
             &[
@@ -353,7 +363,7 @@ class A(object):
 "
             .trim()
         );
-        assert_eq!(fixes.values().sum::<usize>(), 2);
+        assert_eq!(fixes.counts().sum::<usize>(), 2);
         assert_eq!(
             source_map.markers(),
             &[
@@ -395,7 +405,7 @@ class A:
 "
             .trim(),
         );
-        assert_eq!(fixes.values().sum::<usize>(), 1);
+        assert_eq!(fixes.counts().sum::<usize>(), 1);
         assert_eq!(
             source_map.markers(),
             &[

crates/ruff_linter/src/linter.rs

@@ -1,4 +1,5 @@
 use std::borrow::Cow;
+use std::collections::hash_map::Entry;
 use std::path::Path;
 
 use anyhow::{Result, anyhow};
@@ -22,13 +23,14 @@ use crate::checkers::imports::check_imports;
 use crate::checkers::noqa::check_noqa;
 use crate::checkers::physical_lines::check_physical_lines;
 use crate::checkers::tokens::check_tokens;
+use crate::codes::NoqaCode;
 use crate::directives::Directives;
 use crate::doc_lines::{doc_lines_from_ast, doc_lines_from_tokens};
 use crate::fix::{FixResult, fix_file};
 use crate::message::Message;
 use crate::noqa::add_noqa;
 use crate::package::PackageRoot;
-use crate::preview::{is_py314_support_enabled, is_unsupported_syntax_enabled};
+use crate::preview::is_py314_support_enabled;
 use crate::registry::{AsRule, Rule, RuleSet};
 #[cfg(any(feature = "test-rules", test))]
 use crate::rules::ruff::rules::test_rules::{self, TEST_RULES, TestRule};
@@ -84,7 +86,53 @@ impl LinterResult {
     }
 }
 
-pub type FixTable = FxHashMap<Rule, usize>;
+#[derive(Debug, Default, PartialEq)]
+struct FixCount {
+    rule_name: &'static str,
+    count: usize,
+}
+
+/// A mapping from a noqa code to the corresponding lint name and a count of applied fixes.
+#[derive(Debug, Default, PartialEq)]
+pub struct FixTable(FxHashMap<NoqaCode, FixCount>);
+
+impl FixTable {
+    pub fn counts(&self) -> impl Iterator<Item = usize> {
+        self.0.values().map(|fc| fc.count)
+    }
+
+    pub fn entry(&mut self, code: NoqaCode) -> FixTableEntry {
+        FixTableEntry(self.0.entry(code))
+    }
+
+    pub fn iter(&self) -> impl Iterator<Item = (NoqaCode, &'static str, usize)> {
+        self.0
+            .iter()
+            .map(|(code, FixCount { rule_name, count })| (*code, *rule_name, *count))
+    }
+
+    pub fn keys(&self) -> impl Iterator<Item = NoqaCode> {
+        self.0.keys().copied()
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.0.is_empty()
+    }
+}
+
+pub struct FixTableEntry<'a>(Entry<'a, NoqaCode, FixCount>);
+
+impl<'a> FixTableEntry<'a> {
+    pub fn or_default(self, rule_name: &'static str) -> &'a mut usize {
+        &mut (self
+            .0
+            .or_insert(FixCount {
+                rule_name,
+                count: 0,
+            })
+            .count)
+    }
+}
 
 pub struct FixerResult<'a> {
     /// The result returned by the linter, after applying any fixes.
@@ -399,11 +447,7 @@ pub fn check_path(
         }
     }
 
-    let syntax_errors = if is_unsupported_syntax_enabled(settings) {
-        parsed.unsupported_syntax_errors()
-    } else {
-        &[]
-    };
+    let syntax_errors = parsed.unsupported_syntax_errors();
 
     diagnostics_to_messages(
         diagnostics,
@@ -581,7 +625,7 @@ pub fn lint_fix<'a>(
     let mut transformed = Cow::Borrowed(source_kind);
 
     // Track the number of fixed errors across iterations.
-    let mut fixed = FxHashMap::default();
+    let mut fixed = FixTable::default();
 
     // As an escape hatch, bail after 100 iterations.
     let mut iterations = 0;
@@ -650,12 +694,7 @@ pub fn lint_fix<'a>(
             // syntax error. Return the original code.
             if has_valid_syntax && has_no_syntax_errors {
                 if let Some(error) = parsed.errors().first() {
-                    report_fix_syntax_error(
-                        path,
-                        transformed.source_code(),
-                        error,
-                        fixed.keys().copied(),
-                    );
+                    report_fix_syntax_error(path, transformed.source_code(), error, fixed.keys());
                     return Err(anyhow!("Fix introduced a syntax error"));
                 }
             }
@@ -670,8 +709,8 @@ pub fn lint_fix<'a>(
         {
             if iterations < MAX_ITERATIONS {
                 // Count the number of fixed errors.
-                for (rule, count) in applied {
-                    *fixed.entry(rule).or_default() += count;
+                for (rule, name, count) in applied.iter() {
+                    *fixed.entry(rule).or_default(name) += count;
                 }
 
                 transformed = Cow::Owned(transformed.updated(fixed_contents, &source_map));
@@ -698,10 +737,10 @@ pub fn lint_fix<'a>(
     }
 }
 
-fn collect_rule_codes(rules: impl IntoIterator<Item = Rule>) -> String {
+fn collect_rule_codes(rules: impl IntoIterator<Item = NoqaCode>) -> String {
     rules
         .into_iter()
-        .map(|rule| rule.noqa_code().to_string())
+        .map(|rule| rule.to_string())
         .sorted_unstable()
         .dedup()
         .join(", ")
@@ -709,7 +748,7 @@ fn collect_rule_codes(rules: impl IntoIterator<Item = Rule>) -> String {
 
 #[expect(clippy::print_stderr)]
 fn report_failed_to_converge_error(path: &Path, transformed: &str, messages: &[Message]) {
-    let codes = collect_rule_codes(messages.iter().filter_map(Message::to_rule));
+    let codes = collect_rule_codes(messages.iter().filter_map(Message::noqa_code));
     if cfg!(debug_assertions) {
         eprintln!(
             "{}{} Failed to converge after {} iterations in `{}` with rule codes {}:---\n{}\n---",
@@ -745,7 +784,7 @@ fn report_fix_syntax_error(
     path: &Path,
     transformed: &str,
     error: &ParseError,
-    rules: impl IntoIterator<Item = Rule>,
+    rules: impl IntoIterator<Item = NoqaCode>,
 ) {
     let codes = collect_rule_codes(rules);
     if cfg!(debug_assertions) {

crates/ruff_linter/src/message/azure.rs

@@ -33,7 +33,7 @@ impl Emitter for AzureEmitter {
                 line = location.line,
                 col = location.column,
                 code = message
-                    .to_noqa_code()
+                    .noqa_code()
                     .map_or_else(String::new, |code| format!("code={code};")),
                 body = message.body(),
             )?;

crates/ruff_linter/src/message/github.rs

@@ -33,7 +33,7 @@ impl Emitter for GithubEmitter {
                 writer,
                 "::error title=Ruff{code},file={file},line={row},col={column},endLine={end_row},endColumn={end_column}::",
                 code = message
-                    .to_noqa_code()
+                    .noqa_code()
                     .map_or_else(String::new, |code| format!(" ({code})")),
                 file = message.filename(),
                 row = source_location.line,
@@ -50,7 +50,7 @@ impl Emitter for GithubEmitter {
                 column = location.column,
             )?;
 
-            if let Some(code) = message.to_noqa_code() {
+            if let Some(code) = message.noqa_code() {
                 write!(writer, " {code}")?;
             }
 

crates/ruff_linter/src/message/gitlab.rs

@@ -90,7 +90,7 @@ impl Serialize for SerializedMessages<'_> {
             }
             fingerprints.insert(message_fingerprint);
 
-            let (description, check_name) = if let Some(code) = message.to_noqa_code() {
+            let (description, check_name) = if let Some(code) = message.noqa_code() {
                 (message.body().to_string(), code.to_string())
             } else {
                 let description = message.body();

crates/ruff_linter/src/message/json.rs

@@ -81,8 +81,8 @@ pub(crate) fn message_to_json_value(message: &Message, context: &EmitterContext)
     }
 
     json!({
-        "code": message.to_noqa_code().map(|code| code.to_string()),
-        "url": message.to_rule().and_then(|rule| rule.url()),
+        "code": message.noqa_code().map(|code| code.to_string()),
+        "url": message.to_url(),
         "message": message.body(),
         "fix": fix,
         "cell": notebook_cell_index,

crates/ruff_linter/src/message/junit.rs

@@ -59,7 +59,7 @@ impl Emitter for JunitEmitter {
                         body = message.body()
                     ));
                     let mut case = TestCase::new(
-                        if let Some(code) = message.to_noqa_code() {
+                        if let Some(code) = message.noqa_code() {
                             format!("org.ruff.{code}")
                         } else {
                             "org.ruff".to_string()

crates/ruff_linter/src/message/mod.rs

@@ -224,30 +224,22 @@ impl Message {
         self.fix().is_some()
     }
 
-    /// Returns the [`Rule`] corresponding to the diagnostic message.
-    pub fn to_rule(&self) -> Option<Rule> {
-        if self.is_syntax_error() {
-            None
-        } else {
-            Some(self.name().parse().expect("Expected a valid rule name"))
-        }
-    }
-
     /// Returns the [`NoqaCode`] corresponding to the diagnostic message.
-    pub fn to_noqa_code(&self) -> Option<NoqaCode> {
+    pub fn noqa_code(&self) -> Option<NoqaCode> {
         self.noqa_code
     }
 
     /// Returns the URL for the rule documentation, if it exists.
     pub fn to_url(&self) -> Option<String> {
-        // TODO(brent) Rule::url calls Rule::explanation, which calls ViolationMetadata::explain,
-        // which when derived (seems always to be the case?) is always `Some`, so I think it's
-        // pretty safe to inline the Rule::url implementation here, using `self.name()`:
-        //
-        // format!("{}/rules/{}", env!("CARGO_PKG_HOMEPAGE"), self.name())
-        //
-        // at least in the case of diagnostics, I guess syntax errors will return None
-        self.to_rule().and_then(|rule| rule.url())
+        if self.is_syntax_error() {
+            None
+        } else {
+            Some(format!(
+                "{}/rules/{}",
+                env!("CARGO_PKG_HOMEPAGE"),
+                self.name()
+            ))
+        }
     }
 
     /// Returns the filename for the message.

crates/ruff_linter/src/message/pylint.rs

@@ -26,7 +26,7 @@ impl Emitter for PylintEmitter {
                 message.compute_start_location().line
             };
 
-            let body = if let Some(code) = message.to_noqa_code() {
+            let body = if let Some(code) = message.noqa_code() {
                 format!("[{code}] {body}", body = message.body())
             } else {
                 message.body().to_string()

crates/ruff_linter/src/message/rdjson.rs

@@ -71,7 +71,7 @@ fn message_to_rdjson_value(message: &Message) -> Value {
                 "range": rdjson_range(start_location, end_location),
             },
             "code": {
-                "value": message.to_noqa_code().map(|code| code.to_string()),
+                "value": message.noqa_code().map(|code| code.to_string()),
                 "url": message.to_url(),
             },
             "suggestions": rdjson_suggestions(fix.edits(), &source_code),
@@ -84,7 +84,7 @@ fn message_to_rdjson_value(message: &Message) -> Value {
                 "range": rdjson_range(start_location, end_location),
             },
             "code": {
-                "value": message.to_noqa_code().map(|code| code.to_string()),
+                "value": message.noqa_code().map(|code| code.to_string()),
                 "url": message.to_url(),
             },
         })

crates/ruff_linter/src/message/sarif.rs

@@ -8,7 +8,7 @@ use serde_json::json;
 use ruff_source_file::OneIndexed;
 
 use crate::VERSION;
-use crate::codes::Rule;
+use crate::codes::NoqaCode;
 use crate::fs::normalize_path;
 use crate::message::{Emitter, EmitterContext, Message};
 use crate::registry::{Linter, RuleNamespace};
@@ -27,7 +27,7 @@ impl Emitter for SarifEmitter {
             .map(SarifResult::from_message)
             .collect::<Result<Vec<_>>>()?;
 
-        let unique_rules: HashSet<_> = results.iter().filter_map(|result| result.rule).collect();
+        let unique_rules: HashSet<_> = results.iter().filter_map(|result| result.code).collect();
         let mut rules: Vec<SarifRule> = unique_rules.into_iter().map(SarifRule::from).collect();
         rules.sort_by(|a, b| a.code.cmp(&b.code));
 
@@ -61,13 +61,19 @@ struct SarifRule<'a> {
     url: Option<String>,
 }
 
-impl From<Rule> for SarifRule<'_> {
-    fn from(rule: Rule) -> Self {
-        let code = rule.noqa_code().to_string();
-        let (linter, _) = Linter::parse_code(&code).unwrap();
+impl From<NoqaCode> for SarifRule<'_> {
+    fn from(code: NoqaCode) -> Self {
+        let code_str = code.to_string();
+        // This is a manual re-implementation of Rule::from_code, but we also want the Linter. This
+        // avoids calling Linter::parse_code twice.
+        let (linter, suffix) = Linter::parse_code(&code_str).unwrap();
+        let rule = linter
+            .all_rules()
+            .find(|rule| rule.noqa_code().suffix() == suffix)
+            .expect("Expected a valid noqa code corresponding to a rule");
         Self {
             name: rule.into(),
-            code,
+            code: code_str,
             linter: linter.name(),
             summary: rule.message_formats()[0],
             explanation: rule.explanation(),
@@ -106,7 +112,7 @@ impl Serialize for SarifRule<'_> {
 
 #[derive(Debug)]
 struct SarifResult {
-    rule: Option<Rule>,
+    code: Option<NoqaCode>,
     level: String,
     message: String,
     uri: String,
@@ -123,7 +129,7 @@ impl SarifResult {
         let end_location = message.compute_end_location();
         let path = normalize_path(&*message.filename());
         Ok(Self {
-            rule: message.to_rule(),
+            code: message.noqa_code(),
             level: "error".to_string(),
             message: message.body().to_string(),
             uri: url::Url::from_file_path(&path)
@@ -143,7 +149,7 @@ impl SarifResult {
         let end_location = message.compute_end_location();
         let path = normalize_path(&*message.filename());
         Ok(Self {
-            rule: message.to_rule(),
+            code: message.noqa_code(),
             level: "error".to_string(),
             message: message.body().to_string(),
             uri: path.display().to_string(),
@@ -178,7 +184,7 @@ impl Serialize for SarifResult {
                     }
                 }
             }],
-            "ruleId": self.rule.map(|rule| rule.noqa_code().to_string()),
+            "ruleId": self.code.map(|code| code.to_string()),
         })
         .serialize(serializer)
     }

crates/ruff_linter/src/message/text.rs

@@ -151,7 +151,7 @@ impl Display for RuleCodeAndBody<'_> {
             if let Some(fix) = self.message.fix() {
                 // Do not display an indicator for inapplicable fixes
                 if fix.applies(self.unsafe_fixes.required_applicability()) {
-                    if let Some(code) = self.message.to_noqa_code() {
+                    if let Some(code) = self.message.noqa_code() {
                         write!(f, "{} ", code.to_string().red().bold())?;
                     }
                     return write!(
@@ -164,7 +164,7 @@ impl Display for RuleCodeAndBody<'_> {
             }
         }
 
-        if let Some(code) = self.message.to_noqa_code() {
+        if let Some(code) = self.message.noqa_code() {
             write!(
                 f,
                 "{code} {body}",
@@ -254,7 +254,7 @@ impl Display for MessageCodeFrame<'_> {
 
         let label = self
             .message
-            .to_noqa_code()
+            .noqa_code()
             .map_or_else(String::new, |code| code.to_string());
 
         let line_start = self.notebook_index.map_or_else(

crates/ruff_linter/src/noqa.rs

@@ -12,13 +12,14 @@ use log::warn;
 use ruff_python_trivia::{CommentRanges, Cursor, indentation_at_offset};
 use ruff_source_file::{LineEnding, LineRanges};
 use ruff_text_size::{Ranged, TextLen, TextRange, TextSize};
+use rustc_hash::FxHashSet;
 
 use crate::Edit;
 use crate::Locator;
 use crate::codes::NoqaCode;
 use crate::fs::relativize_path;
 use crate::message::Message;
-use crate::registry::{Rule, RuleSet};
+use crate::registry::Rule;
 use crate::rule_redirects::get_redirect_target;
 
 /// Generates an array of edits that matches the length of `messages`.
@@ -780,7 +781,7 @@ fn build_noqa_edits_by_diagnostic(
                 if let Some(noqa_edit) = generate_noqa_edit(
                     comment.directive,
                     comment.line,
-                    RuleSet::from_rule(comment.rule),
+                    FxHashSet::from_iter([comment.code]),
                     locator,
                     line_ending,
                 ) {
@@ -816,7 +817,7 @@ fn build_noqa_edits_by_line<'a>(
             offset,
             matches
                 .into_iter()
-                .map(|NoqaComment { rule, .. }| rule)
+                .map(|NoqaComment { code, .. }| code)
                 .collect(),
             locator,
             line_ending,
@@ -829,7 +830,7 @@ fn build_noqa_edits_by_line<'a>(
 
 struct NoqaComment<'a> {
     line: TextSize,
-    rule: Rule,
+    code: NoqaCode,
     directive: Option<&'a Directive<'a>>,
 }
 
@@ -845,13 +846,11 @@ fn find_noqa_comments<'a>(
 
     // Mark any non-ignored diagnostics.
     for message in messages {
-        let Some(rule) = message.to_rule() else {
+        let Some(code) = message.noqa_code() else {
             comments_by_line.push(None);
             continue;
         };
 
-        let code = rule.noqa_code();
-
         match &exemption {
             FileExemption::All(_) => {
                 // If the file is exempted, don't add any noqa directives.
@@ -900,7 +899,7 @@ fn find_noqa_comments<'a>(
                     if !codes.includes(code) {
                         comments_by_line.push(Some(NoqaComment {
                             line: directive_line.start(),
-                            rule,
+                            code,
                             directive: Some(directive),
                         }));
                     }
@@ -912,7 +911,7 @@ fn find_noqa_comments<'a>(
         // There's no existing noqa directive that suppresses the diagnostic.
         comments_by_line.push(Some(NoqaComment {
             line: locator.line_start(noqa_offset),
-            rule,
+            code,
             directive: None,
         }));
     }
@@ -922,7 +921,7 @@ fn find_noqa_comments<'a>(
 
 struct NoqaEdit<'a> {
     edit_range: TextRange,
-    rules: RuleSet,
+    noqa_codes: FxHashSet<NoqaCode>,
     codes: Option<&'a Codes<'a>>,
     line_ending: LineEnding,
 }
@@ -941,18 +940,15 @@ impl NoqaEdit<'_> {
             Some(codes) => {
                 push_codes(
                     writer,
-                    self.rules
+                    self.noqa_codes
                         .iter()
-                        .map(|rule| rule.noqa_code().to_string())
+                        .map(ToString::to_string)
                         .chain(codes.iter().map(ToString::to_string))
                         .sorted_unstable(),
                 );
             }
             None => {
-                push_codes(
-                    writer,
-                    self.rules.iter().map(|rule| rule.noqa_code().to_string()),
-                );
+                push_codes(writer, self.noqa_codes.iter().map(ToString::to_string));
             }
         }
         write!(writer, "{}", self.line_ending.as_str()).unwrap();
@@ -968,7 +964,7 @@ impl Ranged for NoqaEdit<'_> {
 fn generate_noqa_edit<'a>(
     directive: Option<&'a Directive>,
     offset: TextSize,
-    rules: RuleSet,
+    noqa_codes: FxHashSet<NoqaCode>,
     locator: &Locator,
     line_ending: LineEnding,
 ) -> Option<NoqaEdit<'a>> {
@@ -997,7 +993,7 @@ fn generate_noqa_edit<'a>(
 
     Some(NoqaEdit {
         edit_range,
-        rules,
+        noqa_codes,
         codes,
         line_ending,
     })

crates/ruff_linter/src/preview.rs

@@ -7,17 +7,6 @@
 
 use crate::settings::LinterSettings;
 
-// https://github.com/astral-sh/ruff/issues/17412
-// https://github.com/astral-sh/ruff/issues/11934
-pub(crate) const fn is_semantic_errors_enabled(settings: &LinterSettings) -> bool {
-    settings.preview.is_enabled()
-}
-
-// https://github.com/astral-sh/ruff/pull/16429
-pub(crate) const fn is_unsupported_syntax_enabled(settings: &LinterSettings) -> bool {
-    settings.preview.is_enabled()
-}
-
 pub(crate) const fn is_py314_support_enabled(settings: &LinterSettings) -> bool {
     settings.preview.is_enabled()
 }
@@ -29,23 +18,11 @@ pub(crate) const fn is_full_path_match_source_strategy_enabled(settings: &Linter
 
 // Rule-specific behavior
 
-// https://github.com/astral-sh/ruff/pull/17136
-pub(crate) const fn is_shell_injection_only_trusted_input_enabled(
-    settings: &LinterSettings,
-) -> bool {
-    settings.preview.is_enabled()
-}
-
 // https://github.com/astral-sh/ruff/pull/15541
 pub(crate) const fn is_suspicious_function_reference_enabled(settings: &LinterSettings) -> bool {
     settings.preview.is_enabled()
 }
 
-// https://github.com/astral-sh/ruff/pull/7501
-pub(crate) const fn is_bool_subtype_of_annotation_enabled(settings: &LinterSettings) -> bool {
-    settings.preview.is_enabled()
-}
-
 // https://github.com/astral-sh/ruff/pull/10759
 pub(crate) const fn is_comprehension_with_min_max_sum_enabled(settings: &LinterSettings) -> bool {
     settings.preview.is_enabled()
@@ -63,21 +40,11 @@ pub(crate) const fn is_bad_version_info_in_non_stub_enabled(settings: &LinterSet
     settings.preview.is_enabled()
 }
 
-// https://github.com/astral-sh/ruff/pull/12676
-pub(crate) const fn is_fix_future_annotations_in_stub_enabled(settings: &LinterSettings) -> bool {
-    settings.preview.is_enabled()
-}
-
 // https://github.com/astral-sh/ruff/pull/11074
 pub(crate) const fn is_only_add_return_none_at_end_enabled(settings: &LinterSettings) -> bool {
     settings.preview.is_enabled()
 }
 
-// https://github.com/astral-sh/ruff/pull/12796
-pub(crate) const fn is_simplify_ternary_to_binary_enabled(settings: &LinterSettings) -> bool {
-    settings.preview.is_enabled()
-}
-
 // https://github.com/astral-sh/ruff/pull/16719
 pub(crate) const fn is_fix_manual_dict_comprehension_enabled(settings: &LinterSettings) -> bool {
     settings.preview.is_enabled()
@@ -104,13 +71,6 @@ pub(crate) const fn is_unicode_to_unicode_confusables_enabled(settings: &LinterS
     settings.preview.is_enabled()
 }
 
-// https://github.com/astral-sh/ruff/pull/17078
-pub(crate) const fn is_support_slices_in_literal_concatenation_enabled(
-    settings: &LinterSettings,
-) -> bool {
-    settings.preview.is_enabled()
-}
-
 // https://github.com/astral-sh/ruff/pull/11370
 pub(crate) const fn is_undefined_export_in_dunder_init_enabled(settings: &LinterSettings) -> bool {
     settings.preview.is_enabled()
@@ -121,16 +81,9 @@ pub(crate) const fn is_allow_nested_roots_enabled(settings: &LinterSettings) ->
     settings.preview.is_enabled()
 }
 
-// https://github.com/astral-sh/ruff/pull/17061
-pub(crate) const fn is_check_file_level_directives_enabled(settings: &LinterSettings) -> bool {
-    settings.preview.is_enabled()
-}
-
-// https://github.com/astral-sh/ruff/pull/17644
-pub(crate) const fn is_readlines_in_for_fix_safe_enabled(settings: &LinterSettings) -> bool {
-    settings.preview.is_enabled()
-}
-
-pub(crate) const fn multiple_with_statements_fix_safe_enabled(settings: &LinterSettings) -> bool {
+// https://github.com/astral-sh/ruff/pull/18208
+pub(crate) const fn is_multiple_with_statements_fix_safe_enabled(
+    settings: &LinterSettings,
+) -> bool {
     settings.preview.is_enabled()
 }

crates/ruff_linter/src/registry.rs

@@ -1,6 +1,7 @@
 //! Remnant of the registry of all [`Rule`] implementations, now it's reexporting from codes.rs
 //! with some helper symbols
 
+use ruff_db::diagnostic::LintName;
 use strum_macros::EnumIter;
 
 pub use codes::Rule;
@@ -348,9 +349,18 @@ impl Rule {
 
     /// Return the URL for the rule documentation, if it exists.
     pub fn url(&self) -> Option<String> {
-        self.explanation()
-            .is_some()
-            .then(|| format!("{}/rules/{}", env!("CARGO_PKG_HOMEPAGE"), self.as_ref()))
+        self.explanation().is_some().then(|| {
+            format!(
+                "{}/rules/{name}",
+                env!("CARGO_PKG_HOMEPAGE"),
+                name = self.name()
+            )
+        })
+    }
+
+    pub fn name(&self) -> LintName {
+        let name: &'static str = self.into();
+        LintName::of(name)
     }
 }
 
@@ -421,7 +431,7 @@ pub mod clap_completion {
         fn possible_values(&self) -> Option<Box<dyn Iterator<Item = PossibleValue> + '_>> {
             Some(Box::new(Rule::iter().map(|rule| {
                 let name = rule.noqa_code().to_string();
-                let help = rule.as_ref().to_string();
+                let help = rule.name().as_str();
                 PossibleValue::new(name).help(help)
             })))
         }
@@ -443,7 +453,7 @@ mod tests {
             assert!(
                 rule.explanation().is_some(),
                 "Rule {} is missing documentation",
-                rule.as_ref()
+                rule.name()
             );
         }
     }
@@ -460,10 +470,10 @@ mod tests {
             .collect();
 
         for rule in Rule::iter() {
-            let rule_name = rule.as_ref();
+            let rule_name = rule.name();
             for pattern in &patterns {
                 assert!(
-                    !pattern.matches(rule_name),
+                    !pattern.matches(&rule_name),
                     "{rule_name} does not match naming convention, see CONTRIBUTING.md"
                 );
             }

crates/ruff_linter/src/registry/rule_set.rs

@@ -302,9 +302,8 @@ impl Display for RuleSet {
         } else {
             writeln!(f, "[")?;
             for rule in self {
-                let name = rule.as_ref();
                 let code = rule.noqa_code();
-                writeln!(f, "\t{name} ({code}),")?;
+                writeln!(f, "\t{name} ({code}),", name = rule.name())?;
             }
             write!(f, "]")?;
         }

crates/ruff_linter/src/rule_selector.rs

@@ -485,8 +485,7 @@ pub mod clap_completion {
                                     prefix.linter().common_prefix(),
                                     prefix.short_code()
                                 );
-                                let name: &'static str = rule.into();
-                                return Some(PossibleValue::new(code).help(name));
+                                return Some(PossibleValue::new(code).help(rule.name().as_str()));
                             }
 
                             None

crates/ruff_linter/src/rules/fastapi/mod.rs

@@ -3,7 +3,6 @@ pub(crate) mod rules;
 
 #[cfg(test)]
 mod tests {
-    use std::convert::AsRef;
     use std::path::Path;
 
     use anyhow::Result;
@@ -18,7 +17,7 @@ mod tests {
     #[test_case(Rule::FastApiNonAnnotatedDependency, Path::new("FAST002_1.py"))]
     #[test_case(Rule::FastApiUnusedPathParameter, Path::new("FAST003.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("fastapi").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),
@@ -32,7 +31,7 @@ mod tests {
     #[test_case(Rule::FastApiNonAnnotatedDependency, Path::new("FAST002_0.py"))]
     #[test_case(Rule::FastApiNonAnnotatedDependency, Path::new("FAST002_1.py"))]
     fn rules_py38(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}_py38", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}_py38", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("fastapi").join(path).as_path(),
             &settings::LinterSettings {

crates/ruff_linter/src/rules/flake8_bandit/mod.rs

@@ -104,7 +104,6 @@ mod tests {
     #[test_case(Rule::SuspiciousURLOpenUsage, Path::new("S310.py"))]
     #[test_case(Rule::SuspiciousNonCryptographicRandomUsage, Path::new("S311.py"))]
     #[test_case(Rule::SuspiciousTelnetUsage, Path::new("S312.py"))]
-    #[test_case(Rule::SubprocessWithoutShellEqualsTrue, Path::new("S603.py"))]
     fn preview_rules(rule_code: Rule, path: &Path) -> Result<()> {
         let snapshot = format!(
             "preview__{}_{}",

crates/ruff_linter/src/rules/flake8_bandit/rules/shell_injection.rs

@@ -7,7 +7,6 @@ use ruff_python_semantic::SemanticModel;
 use ruff_text_size::Ranged;
 
 use crate::Violation;
-use crate::preview::is_shell_injection_only_trusted_input_enabled;
 use crate::{
     checkers::ast::Checker, registry::Rule, rules::flake8_bandit::helpers::string_literal,
 };
@@ -325,9 +324,7 @@ pub(crate) fn shell_injection(checker: &Checker, call: &ast::ExprCall) {
                 }
                 // S603
                 _ => {
-                    if !is_trusted_input(arg)
-                        || !is_shell_injection_only_trusted_input_enabled(checker.settings)
-                    {
+                    if !is_trusted_input(arg) {
                         if checker.enabled(Rule::SubprocessWithoutShellEqualsTrue) {
                             checker.report_diagnostic(
                                 SubprocessWithoutShellEqualsTrue,

crates/ruff_linter/src/rules/flake8_bandit/snapshots/ruff_linter__rules__flake8_bandit__tests__S603_S603.py.snap

@@ -106,74 +106,6 @@ S603.py:21:1: S603 `subprocess` call: check for execution of untrusted input
 23 | # Literals are fine, they're trusted.
    |
 
-S603.py:24:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-23 | # Literals are fine, they're trusted.
-24 | run("true")
-   | ^^^ S603
-25 | Popen(["true"])
-26 | Popen("true", shell=False)
-   |
-
-S603.py:25:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-23 | # Literals are fine, they're trusted.
-24 | run("true")
-25 | Popen(["true"])
-   | ^^^^^ S603
-26 | Popen("true", shell=False)
-27 | call("true", shell=False)
-   |
-
-S603.py:26:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-24 | run("true")
-25 | Popen(["true"])
-26 | Popen("true", shell=False)
-   | ^^^^^ S603
-27 | call("true", shell=False)
-28 | check_call("true", shell=False)
-   |
-
-S603.py:27:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-25 | Popen(["true"])
-26 | Popen("true", shell=False)
-27 | call("true", shell=False)
-   | ^^^^ S603
-28 | check_call("true", shell=False)
-29 | check_output("true", shell=False)
-   |
-
-S603.py:28:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-26 | Popen("true", shell=False)
-27 | call("true", shell=False)
-28 | check_call("true", shell=False)
-   | ^^^^^^^^^^ S603
-29 | check_output("true", shell=False)
-30 | run("true", shell=False)
-   |
-
-S603.py:29:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-27 | call("true", shell=False)
-28 | check_call("true", shell=False)
-29 | check_output("true", shell=False)
-   | ^^^^^^^^^^^^ S603
-30 | run("true", shell=False)
-   |
-
-S603.py:30:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-28 | check_call("true", shell=False)
-29 | check_output("true", shell=False)
-30 | run("true", shell=False)
-   | ^^^ S603
-31 |
-32 | # Not through assignments though.
-   |
-
 S603.py:34:1: S603 `subprocess` call: check for execution of untrusted input
    |
 32 | # Not through assignments though.
@@ -184,15 +116,6 @@ S603.py:34:1: S603 `subprocess` call: check for execution of untrusted input
 36 | # Instant named expressions are fine.
    |
 
-S603.py:37:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-36 | # Instant named expressions are fine.
-37 | run(c := "true")
-   | ^^^ S603
-38 |
-39 | # But non-instant are not.
-   |
-
 S603.py:41:1: S603 `subprocess` call: check for execution of untrusted input
    |
 39 | # But non-instant are not.
@@ -200,20 +123,3 @@ S603.py:41:1: S603 `subprocess` call: check for execution of untrusted input
 41 | run(e)
    | ^^^ S603
    |
-
-S603.py:46:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-44 | # https://github.com/astral-sh/ruff/issues/17798
-45 | # Tuple literals are trusted
-46 | check_output(("literal", "cmd", "using", "tuple"), text=True)
-   | ^^^^^^^^^^^^ S603
-47 | Popen(("literal", "cmd", "using", "tuple"))
-   |
-
-S603.py:47:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-45 | # Tuple literals are trusted
-46 | check_output(("literal", "cmd", "using", "tuple"), text=True)
-47 | Popen(("literal", "cmd", "using", "tuple"))
-   | ^^^^^ S603
-   |

crates/ruff_linter/src/rules/flake8_bandit/snapshots/ruff_linter__rules__flake8_bandit__tests__preview__S603_S603.py.snap

@@ -1,125 +0,0 @@
----
-source: crates/ruff_linter/src/rules/flake8_bandit/mod.rs
----
-S603.py:5:1: S603 `subprocess` call: check for execution of untrusted input
-  |
-3 | # Different Popen wrappers are checked.
-4 | a = input()
-5 | Popen(a, shell=False)
-  | ^^^^^ S603
-6 | call(a, shell=False)
-7 | check_call(a, shell=False)
-  |
-
-S603.py:6:1: S603 `subprocess` call: check for execution of untrusted input
-  |
-4 | a = input()
-5 | Popen(a, shell=False)
-6 | call(a, shell=False)
-  | ^^^^ S603
-7 | check_call(a, shell=False)
-8 | check_output(a, shell=False)
-  |
-
-S603.py:7:1: S603 `subprocess` call: check for execution of untrusted input
-  |
-5 | Popen(a, shell=False)
-6 | call(a, shell=False)
-7 | check_call(a, shell=False)
-  | ^^^^^^^^^^ S603
-8 | check_output(a, shell=False)
-9 | run(a, shell=False)
-  |
-
-S603.py:8:1: S603 `subprocess` call: check for execution of untrusted input
-  |
-6 | call(a, shell=False)
-7 | check_call(a, shell=False)
-8 | check_output(a, shell=False)
-  | ^^^^^^^^^^^^ S603
-9 | run(a, shell=False)
-  |
-
-S603.py:9:1: S603 `subprocess` call: check for execution of untrusted input
-   |
- 7 | check_call(a, shell=False)
- 8 | check_output(a, shell=False)
- 9 | run(a, shell=False)
-   | ^^^ S603
-10 |
-11 | # Falsey values are treated as false.
-   |
-
-S603.py:12:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-11 | # Falsey values are treated as false.
-12 | Popen(a, shell=0)
-   | ^^^^^ S603
-13 | Popen(a, shell=[])
-14 | Popen(a, shell={})
-   |
-
-S603.py:13:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-11 | # Falsey values are treated as false.
-12 | Popen(a, shell=0)
-13 | Popen(a, shell=[])
-   | ^^^^^ S603
-14 | Popen(a, shell={})
-15 | Popen(a, shell=None)
-   |
-
-S603.py:14:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-12 | Popen(a, shell=0)
-13 | Popen(a, shell=[])
-14 | Popen(a, shell={})
-   | ^^^^^ S603
-15 | Popen(a, shell=None)
-   |
-
-S603.py:15:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-13 | Popen(a, shell=[])
-14 | Popen(a, shell={})
-15 | Popen(a, shell=None)
-   | ^^^^^ S603
-16 |
-17 | # Unknown values are treated as falsey.
-   |
-
-S603.py:18:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-17 | # Unknown values are treated as falsey.
-18 | Popen(a, shell=True if True else False)
-   | ^^^^^ S603
-19 |
-20 | # No value is also caught.
-   |
-
-S603.py:21:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-20 | # No value is also caught.
-21 | Popen(a)
-   | ^^^^^ S603
-22 |
-23 | # Literals are fine, they're trusted.
-   |
-
-S603.py:34:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-32 | # Not through assignments though.
-33 | cmd = ["true"]
-34 | run(cmd)
-   | ^^^ S603
-35 |
-36 | # Instant named expressions are fine.
-   |
-
-S603.py:41:1: S603 `subprocess` call: check for execution of untrusted input
-   |
-39 | # But non-instant are not.
-40 | (e := "echo")
-41 | run(e)
-   | ^^^ S603
-   |

crates/ruff_linter/src/rules/flake8_boolean_trap/mod.rs

@@ -12,7 +12,6 @@ mod tests {
 
     use crate::registry::Rule;
     use crate::settings::LinterSettings;
-    use crate::settings::types::PreviewMode;
     use crate::test::test_path;
     use crate::{assert_messages, settings};
 
@@ -29,24 +28,6 @@ mod tests {
         Ok(())
     }
 
-    #[test_case(Rule::BooleanTypeHintPositionalArgument, Path::new("FBT.py"))]
-    fn preview_rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!(
-            "preview__{}_{}",
-            rule_code.noqa_code(),
-            path.to_string_lossy()
-        );
-        let diagnostics = test_path(
-            Path::new("flake8_boolean_trap").join(path).as_path(),
-            &settings::LinterSettings {
-                preview: PreviewMode::Enabled,
-                ..settings::LinterSettings::for_rule(rule_code)
-            },
-        )?;
-        assert_messages!(snapshot, diagnostics);
-        Ok(())
-    }
-
     #[test]
     fn extend_allowed_callable() -> Result<()> {
         let diagnostics = test_path(

crates/ruff_linter/src/rules/flake8_boolean_trap/rules/boolean_type_hint_positional_argument.rs

@@ -7,12 +7,12 @@ use ruff_python_semantic::analyze::visibility;
 
 use crate::Violation;
 use crate::checkers::ast::Checker;
-use crate::preview::is_bool_subtype_of_annotation_enabled;
 use crate::rules::flake8_boolean_trap::helpers::is_allowed_func_def;
 
 /// ## What it does
 /// Checks for the use of boolean positional arguments in function definitions,
-/// as determined by the presence of a `bool` type hint.
+/// as determined by the presence of a type hint containing `bool` as an
+/// evident subtype - e.g. `bool`, `bool | int`, `typing.Optional[bool]`, etc.
 ///
 /// ## Why is this bad?
 /// Calling a function with boolean positional arguments is confusing as the
@@ -30,9 +30,6 @@ use crate::rules::flake8_boolean_trap::helpers::is_allowed_func_def;
 /// Dunder methods that define operators are exempt from this rule, as are
 /// setters and `@override` definitions.
 ///
-/// In [preview], this rule will also flag annotations that include boolean
-/// variants, like `bool | int`.
-///
 /// ## Example
 ///
 /// ```python
@@ -96,8 +93,6 @@ use crate::rules::flake8_boolean_trap::helpers::is_allowed_func_def;
 /// ## References
 /// - [Python documentation: Calls](https://docs.python.org/3/reference/expressions.html#calls)
 /// - [_How to Avoid “The Boolean Trap”_ by Adam Johnson](https://adamj.eu/tech/2021/07/10/python-type-hints-how-to-avoid-the-boolean-trap/)
-///
-/// [preview]: https://docs.astral.sh/ruff/preview/
 #[derive(ViolationMetadata)]
 pub(crate) struct BooleanTypeHintPositionalArgument;
 
@@ -128,14 +123,8 @@ pub(crate) fn boolean_type_hint_positional_argument(
         let Some(annotation) = parameter.annotation() else {
             continue;
         };
-        if is_bool_subtype_of_annotation_enabled(checker.settings) {
-            if !match_annotation_to_complex_bool(annotation, checker.semantic()) {
-                continue;
-            }
-        } else {
-            if !match_annotation_to_literal_bool(annotation) {
-                continue;
-            }
+        if !match_annotation_to_complex_bool(annotation, checker.semantic()) {
+            continue;
         }
 
         // Allow Boolean type hints in setters.
@@ -161,17 +150,6 @@ pub(crate) fn boolean_type_hint_positional_argument(
     }
 }
 
-/// Returns `true` if the annotation is a boolean type hint (e.g., `bool`).
-fn match_annotation_to_literal_bool(annotation: &Expr) -> bool {
-    match annotation {
-        // Ex) `True`
-        Expr::Name(name) => &name.id == "bool",
-        // Ex) `"True"`
-        Expr::StringLiteral(ast::ExprStringLiteral { value, .. }) => value == "bool",
-        _ => false,
-    }
-}
-
 /// Returns `true` if the annotation is a boolean type hint (e.g., `bool`), or a type hint that
 /// includes boolean as a variant (e.g., `bool | int`).
 fn match_annotation_to_complex_bool(annotation: &Expr, semantic: &SemanticModel) -> bool {

crates/ruff_linter/src/rules/flake8_boolean_trap/snapshots/ruff_linter__rules__flake8_boolean_trap__tests__FBT001_FBT.py.snap

@@ -1,6 +1,5 @@
 ---
 source: crates/ruff_linter/src/rules/flake8_boolean_trap/mod.rs
-snapshot_kind: text
 ---
 FBT.py:4:5: FBT001 Boolean-typed positional argument in function definition
   |
@@ -89,3 +88,17 @@ FBT.py:90:19: FBT001 Boolean-typed positional argument in function definition
    |                   ^^^^^ FBT001
 91 |         pass
    |
+
+FBT.py:100:10: FBT001 Boolean-typed positional argument in function definition
+    |
+100 | def func(x: Union[list, Optional[int | str | float | bool]]):
+    |          ^ FBT001
+101 |     pass
+    |
+
+FBT.py:104:10: FBT001 Boolean-typed positional argument in function definition
+    |
+104 | def func(x: bool | str):
+    |          ^ FBT001
+105 |     pass
+    |

crates/ruff_linter/src/rules/flake8_boolean_trap/snapshots/ruff_linter__rules__flake8_boolean_trap__tests__preview__FBT001_FBT.py.snap

@@ -1,105 +0,0 @@
----
-source: crates/ruff_linter/src/rules/flake8_boolean_trap/mod.rs
-snapshot_kind: text
----
-FBT.py:4:5: FBT001 Boolean-typed positional argument in function definition
-  |
-2 |     posonly_nohint,
-3 |     posonly_nonboolhint: int,
-4 |     posonly_boolhint: bool,
-  |     ^^^^^^^^^^^^^^^^ FBT001
-5 |     posonly_boolstrhint: "bool",
-6 |     /,
-  |
-
-FBT.py:5:5: FBT001 Boolean-typed positional argument in function definition
-  |
-3 |     posonly_nonboolhint: int,
-4 |     posonly_boolhint: bool,
-5 |     posonly_boolstrhint: "bool",
-  |     ^^^^^^^^^^^^^^^^^^^ FBT001
-6 |     /,
-7 |     offset,
-  |
-
-FBT.py:10:5: FBT001 Boolean-typed positional argument in function definition
-   |
- 8 |     posorkw_nonvalued_nohint,
- 9 |     posorkw_nonvalued_nonboolhint: int,
-10 |     posorkw_nonvalued_boolhint: bool,
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ FBT001
-11 |     posorkw_nonvalued_boolstrhint: "bool",
-12 |     posorkw_boolvalued_nohint=True,
-   |
-
-FBT.py:11:5: FBT001 Boolean-typed positional argument in function definition
-   |
- 9 |     posorkw_nonvalued_nonboolhint: int,
-10 |     posorkw_nonvalued_boolhint: bool,
-11 |     posorkw_nonvalued_boolstrhint: "bool",
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FBT001
-12 |     posorkw_boolvalued_nohint=True,
-13 |     posorkw_boolvalued_nonboolhint: int = True,
-   |
-
-FBT.py:14:5: FBT001 Boolean-typed positional argument in function definition
-   |
-12 |     posorkw_boolvalued_nohint=True,
-13 |     posorkw_boolvalued_nonboolhint: int = True,
-14 |     posorkw_boolvalued_boolhint: bool = True,
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ FBT001
-15 |     posorkw_boolvalued_boolstrhint: "bool" = True,
-16 |     posorkw_nonboolvalued_nohint=1,
-   |
-
-FBT.py:15:5: FBT001 Boolean-typed positional argument in function definition
-   |
-13 |     posorkw_boolvalued_nonboolhint: int = True,
-14 |     posorkw_boolvalued_boolhint: bool = True,
-15 |     posorkw_boolvalued_boolstrhint: "bool" = True,
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FBT001
-16 |     posorkw_nonboolvalued_nohint=1,
-17 |     posorkw_nonboolvalued_nonboolhint: int = 2,
-   |
-
-FBT.py:18:5: FBT001 Boolean-typed positional argument in function definition
-   |
-16 |     posorkw_nonboolvalued_nohint=1,
-17 |     posorkw_nonboolvalued_nonboolhint: int = 2,
-18 |     posorkw_nonboolvalued_boolhint: bool = 3,
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FBT001
-19 |     posorkw_nonboolvalued_boolstrhint: "bool" = 4,
-20 |     *,
-   |
-
-FBT.py:19:5: FBT001 Boolean-typed positional argument in function definition
-   |
-17 |     posorkw_nonboolvalued_nonboolhint: int = 2,
-18 |     posorkw_nonboolvalued_boolhint: bool = 3,
-19 |     posorkw_nonboolvalued_boolstrhint: "bool" = 4,
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FBT001
-20 |     *,
-21 |     kwonly_nonvalued_nohint,
-   |
-
-FBT.py:90:19: FBT001 Boolean-typed positional argument in function definition
-   |
-89 |     # FBT001: Boolean positional arg in function definition
-90 |     def foo(self, value: bool) -> None:
-   |                   ^^^^^ FBT001
-91 |         pass
-   |
-
-FBT.py:100:10: FBT001 Boolean-typed positional argument in function definition
-    |
-100 | def func(x: Union[list, Optional[int | str | float | bool]]):
-    |          ^ FBT001
-101 |     pass
-    |
-
-FBT.py:104:10: FBT001 Boolean-typed positional argument in function definition
-    |
-104 | def func(x: bool | str):
-    |          ^ FBT001
-105 |     pass
-    |

crates/ruff_linter/src/rules/flake8_fixme/mod.rs

@@ -16,7 +16,7 @@ mod tests {
     #[test_case(Rule::LineContainsTodo; "T003")]
     #[test_case(Rule::LineContainsXxx; "T004")]
     fn rules(rule_code: Rule) -> Result<()> {
-        let snapshot = format!("{}_T00.py", rule_code.as_ref());
+        let snapshot = format!("{}_T00.py", rule_code.name());
         let diagnostics = test_path(
             Path::new("flake8_fixme/T00.py"),
             &settings::LinterSettings::for_rule(rule_code),

crates/ruff_linter/src/rules/flake8_gettext/mod.rs

@@ -29,7 +29,7 @@ mod tests {
     #[test_case(Rule::FormatInGetTextFuncCall, Path::new("INT002.py"))]
     #[test_case(Rule::PrintfInGetTextFuncCall, Path::new("INT003.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_gettext").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),

crates/ruff_linter/src/rules/flake8_pyi/mod.rs

@@ -11,7 +11,6 @@ mod tests {
 
     use crate::registry::Rule;
     use crate::rules::pep8_naming;
-    use crate::settings::types::PreviewMode;
     use crate::test::test_path;
     use crate::{assert_messages, settings};
 
@@ -172,22 +171,4 @@ mod tests {
         assert_messages!(snapshot, diagnostics);
         Ok(())
     }
-
-    #[test_case(Rule::FutureAnnotationsInStub, Path::new("PYI044.pyi"))]
-    fn preview_rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!(
-            "preview__{}_{}",
-            rule_code.noqa_code(),
-            path.to_string_lossy()
-        );
-        let diagnostics = test_path(
-            Path::new("flake8_pyi").join(path).as_path(),
-            &settings::LinterSettings {
-                preview: PreviewMode::Enabled,
-                ..settings::LinterSettings::for_rule(rule_code)
-            },
-        )?;
-        assert_messages!(snapshot, diagnostics);
-        Ok(())
-    }
 }

crates/ruff_linter/src/rules/flake8_pyi/rules/future_annotations_in_stub.rs

@@ -3,7 +3,7 @@ use ruff_python_ast::StmtImportFrom;
 use ruff_macros::{ViolationMetadata, derive_message_formats};
 
 use crate::{Fix, FixAvailability, Violation};
-use crate::{checkers::ast::Checker, fix, preview::is_fix_future_annotations_in_stub_enabled};
+use crate::{checkers::ast::Checker, fix};
 
 /// ## What it does
 /// Checks for the presence of the `from __future__ import annotations` import
@@ -55,20 +55,18 @@ pub(crate) fn from_future_import(checker: &Checker, target: &StmtImportFrom) {
 
     let mut diagnostic = checker.report_diagnostic(FutureAnnotationsInStub, *range);
 
-    if is_fix_future_annotations_in_stub_enabled(checker.settings) {
-        let stmt = checker.semantic().current_statement();
+    let stmt = checker.semantic().current_statement();
 
-        diagnostic.try_set_fix(|| {
-            let edit = fix::edits::remove_unused_imports(
-                std::iter::once("annotations"),
-                stmt,
-                None,
-                checker.locator(),
-                checker.stylist(),
-                checker.indexer(),
-            )?;
+    diagnostic.try_set_fix(|| {
+        let edit = fix::edits::remove_unused_imports(
+            std::iter::once("annotations"),
+            stmt,
+            None,
+            checker.locator(),
+            checker.stylist(),
+            checker.indexer(),
+        )?;
 
-            Ok(Fix::safe_edit(edit))
-        });
-    }
+        Ok(Fix::safe_edit(edit))
+    });
 }

crates/ruff_linter/src/rules/flake8_pyi/snapshots/ruff_linter__rules__flake8_pyi__tests__PYI044_PYI044.pyi.snap

@@ -1,7 +1,7 @@
 ---
 source: crates/ruff_linter/src/rules/flake8_pyi/mod.rs
 ---
-PYI044.pyi:2:1: PYI044 `from __future__ import annotations` has no effect in stub files, since type checkers automatically treat stubs as having those semantics
+PYI044.pyi:2:1: PYI044 [*] `from __future__ import annotations` has no effect in stub files, since type checkers automatically treat stubs as having those semantics
   |
 1 | # Bad import.
 2 | from __future__ import annotations # PYI044.
@@ -10,7 +10,14 @@ PYI044.pyi:2:1: PYI044 `from __future__ import annotations` has no effect in stu
   |
   = help: Remove `from __future__ import annotations`
 
-PYI044.pyi:3:1: PYI044 `from __future__ import annotations` has no effect in stub files, since type checkers automatically treat stubs as having those semantics
+ℹ Safe fix
+1 1 | # Bad import.
+2   |-from __future__ import annotations # PYI044.
+3 2 | from __future__ import annotations, with_statement # PYI044.
+4 3 | 
+5 4 | # Good imports.
+
+PYI044.pyi:3:1: PYI044 [*] `from __future__ import annotations` has no effect in stub files, since type checkers automatically treat stubs as having those semantics
   |
 1 | # Bad import.
 2 | from __future__ import annotations # PYI044.
@@ -20,3 +27,12 @@ PYI044.pyi:3:1: PYI044 `from __future__ import annotations` has no effect in stu
 5 | # Good imports.
   |
   = help: Remove `from __future__ import annotations`
+
+ℹ Safe fix
+1 1 | # Bad import.
+2 2 | from __future__ import annotations # PYI044.
+3   |-from __future__ import annotations, with_statement # PYI044.
+  3 |+from __future__ import with_statement # PYI044.
+4 4 | 
+5 5 | # Good imports.
+6 6 | from __future__ import with_statement

crates/ruff_linter/src/rules/flake8_pyi/snapshots/ruff_linter__rules__flake8_pyi__tests__preview__PYI044_PYI044.pyi.snap

@@ -1,38 +0,0 @@
----
-source: crates/ruff_linter/src/rules/flake8_pyi/mod.rs
----
-PYI044.pyi:2:1: PYI044 [*] `from __future__ import annotations` has no effect in stub files, since type checkers automatically treat stubs as having those semantics
-  |
-1 | # Bad import.
-2 | from __future__ import annotations # PYI044.
-  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ PYI044
-3 | from __future__ import annotations, with_statement # PYI044.
-  |
-  = help: Remove `from __future__ import annotations`
-
-ℹ Safe fix
-1 1 | # Bad import.
-2   |-from __future__ import annotations # PYI044.
-3 2 | from __future__ import annotations, with_statement # PYI044.
-4 3 | 
-5 4 | # Good imports.
-
-PYI044.pyi:3:1: PYI044 [*] `from __future__ import annotations` has no effect in stub files, since type checkers automatically treat stubs as having those semantics
-  |
-1 | # Bad import.
-2 | from __future__ import annotations # PYI044.
-3 | from __future__ import annotations, with_statement # PYI044.
-  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ PYI044
-4 |
-5 | # Good imports.
-  |
-  = help: Remove `from __future__ import annotations`
-
-ℹ Safe fix
-1 1 | # Bad import.
-2 2 | from __future__ import annotations # PYI044.
-3   |-from __future__ import annotations, with_statement # PYI044.
-  3 |+from __future__ import with_statement # PYI044.
-4 4 | 
-5 5 | # Good imports.
-6 6 | from __future__ import with_statement

crates/ruff_linter/src/rules/flake8_raise/mod.rs

@@ -3,7 +3,6 @@ pub(crate) mod rules;
 
 #[cfg(test)]
 mod tests {
-    use std::convert::AsRef;
     use std::path::Path;
 
     use anyhow::Result;
@@ -15,7 +14,7 @@ mod tests {
 
     #[test_case(Rule::UnnecessaryParenOnRaiseException, Path::new("RSE102.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_raise").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),

crates/ruff_linter/src/rules/flake8_self/mod.rs

@@ -4,7 +4,6 @@ pub mod settings;
 
 #[cfg(test)]
 mod tests {
-    use std::convert::AsRef;
     use std::path::Path;
 
     use crate::registry::Rule;
@@ -18,7 +17,7 @@ mod tests {
     #[test_case(Rule::PrivateMemberAccess, Path::new("SLF001.py"))]
     #[test_case(Rule::PrivateMemberAccess, Path::new("SLF001_1.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_self").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),

crates/ruff_linter/src/rules/flake8_simplify/mod.rs

@@ -58,7 +58,6 @@ mod tests {
         Ok(())
     }
 
-    #[test_case(Rule::IfElseBlockInsteadOfIfExp, Path::new("SIM108.py"))]
     #[test_case(Rule::MultipleWithStatements, Path::new("SIM117.py"))]
     fn preview_rules(rule_code: Rule, path: &Path) -> Result<()> {
         let snapshot = format!(

crates/ruff_linter/src/rules/flake8_simplify/rules/ast_with.rs

@@ -10,7 +10,7 @@ use super::fix_with;
 use crate::Fix;
 use crate::checkers::ast::Checker;
 use crate::fix::edits::fits;
-use crate::preview::multiple_with_statements_fix_safe_enabled;
+use crate::preview::is_multiple_with_statements_fix_safe_enabled;
 use crate::{FixAvailability, Violation};
 
 /// ## What it does
@@ -195,7 +195,7 @@ pub(crate) fn multiple_with_statements(
                                 checker.settings.tab_size,
                             )
                         }) {
-                            if multiple_with_statements_fix_safe_enabled(checker.settings) {
+                            if is_multiple_with_statements_fix_safe_enabled(checker.settings) {
                                 Ok(Some(Fix::safe_edit(edit)))
                             } else {
                                 Ok(Some(Fix::unsafe_edit(edit)))

crates/ruff_linter/src/rules/flake8_simplify/rules/if_else_block_instead_of_if_exp.rs

@@ -7,13 +7,14 @@ use ruff_text_size::{Ranged, TextRange};
 
 use crate::checkers::ast::Checker;
 use crate::fix::edits::fits;
-use crate::preview::is_simplify_ternary_to_binary_enabled;
 use crate::{Edit, Fix, FixAvailability, Violation};
 
 /// ## What it does
-/// Check for `if`-`else`-blocks that can be replaced with a ternary operator.
-/// Moreover, in [preview], check if these ternary expressions can be
-/// further simplified to binary expressions.
+/// Check for `if`-`else`-blocks that can be replaced with a ternary
+/// or binary operator.
+///
+/// The lint is suppressed if the suggested replacement would exceed
+/// the maximum line length configured in [pycodestyle.max-line-length].
 ///
 /// ## Why is this bad?
 /// `if`-`else`-blocks that assign a value to a variable in both branches can
@@ -33,7 +34,7 @@ use crate::{Edit, Fix, FixAvailability, Violation};
 /// bar = x if foo else y
 /// ```
 ///
-/// Or, in [preview]:
+/// Or:
 ///
 /// ```python
 /// if cond:
@@ -57,8 +58,8 @@ use crate::{Edit, Fix, FixAvailability, Violation};
 /// ## References
 /// - [Python documentation: Conditional expressions](https://docs.python.org/3/reference/expressions.html#conditional-expressions)
 ///
-/// [preview]: https://docs.astral.sh/ruff/preview/
 /// [code coverage]: https://github.com/nedbat/coveragepy/issues/509
+/// [pycodestyle.max-line-length]: https://docs.astral.sh/ruff/settings/#lint_pycodestyle_max-line-length
 #[derive(ViolationMetadata)]
 pub(crate) struct IfElseBlockInsteadOfIfExp {
     /// The ternary or binary expression to replace the `if`-`else`-block.
@@ -183,16 +184,12 @@ pub(crate) fn if_else_block_instead_of_if_exp(checker: &Checker, stmt_if: &ast::
     //
     // The match statement below implements the following
     // logic:
-    //     - If `test == body_value` and preview enabled, replace with `target_var = test or else_value`
-    //     - If `test == not body_value` and preview enabled, replace with `target_var = body_value and else_value`
-    //     - If `not test == body_value` and preview enabled, replace with `target_var = body_value and else_value`
+    //     - If `test == body_value`, replace with `target_var = test or else_value`
+    //     - If `test == not body_value`, replace with `target_var = body_value and else_value`
+    //     - If `not test == body_value`, replace with `target_var = body_value and else_value`
     //     - Otherwise, replace with `target_var = body_value if test else else_value`
-    let (contents, assignment_kind) = match (
-        is_simplify_ternary_to_binary_enabled(checker.settings),
-        test,
-        body_value,
-    ) {
-        (true, test_node, body_node)
+    let (contents, assignment_kind) = match (test, body_value) {
+        (test_node, body_node)
             if ComparableExpr::from(test_node) == ComparableExpr::from(body_node)
                 && !contains_effect(test_node, |id| checker.semantic().has_builtin_binding(id)) =>
         {
@@ -200,7 +197,7 @@ pub(crate) fn if_else_block_instead_of_if_exp(checker: &Checker, stmt_if: &ast::
             let binary = assignment_binary_or(target_var, body_value, else_value);
             (checker.generator().stmt(&binary), AssignmentKind::Binary)
         }
-        (true, test_node, body_node)
+        (test_node, body_node)
             if (test_node.as_unary_op_expr().is_some_and(|op_expr| {
                 op_expr.op.is_not()
                     && ComparableExpr::from(&op_expr.operand) == ComparableExpr::from(body_node)

crates/ruff_linter/src/rules/flake8_simplify/snapshots/ruff_linter__rules__flake8_simplify__tests__SIM108_SIM108.py.snap

@@ -118,7 +118,7 @@ SIM108.py:117:1: SIM108 Use ternary operator `x = 3 if True else 5` instead of `
     |
     = help: Replace `if`-`else`-block with `x = 3 if True else 5`
 
-SIM108.py:141:1: SIM108 [*] Use ternary operator `z = cond if cond else other_cond` instead of `if`-`else`-block
+SIM108.py:141:1: SIM108 [*] Use binary operator `z = cond or other_cond` instead of `if`-`else`-block
     |
 139 |   # SIM108 - should suggest
 140 |   # z = cond or other_cond
@@ -130,7 +130,7 @@ SIM108.py:141:1: SIM108 [*] Use ternary operator `z = cond if cond else other_co
 145 |
 146 |   # SIM108 - should suggest
     |
-    = help: Replace `if`-`else`-block with `z = cond if cond else other_cond`
+    = help: Replace `if`-`else`-block with `z = cond or other_cond`
 
 ℹ Unsafe fix
 138 138 | 
@@ -140,12 +140,12 @@ SIM108.py:141:1: SIM108 [*] Use ternary operator `z = cond if cond else other_co
 142     |-    z = cond 
 143     |-else:
 144     |-    z = other_cond
-    141 |+z = cond if cond else other_cond
+    141 |+z = cond or other_cond
 145 142 | 
 146 143 | # SIM108 - should suggest
 147 144 | # z = cond and other_cond
 
-SIM108.py:148:1: SIM108 [*] Use ternary operator `z = cond if not cond else other_cond` instead of `if`-`else`-block
+SIM108.py:148:1: SIM108 [*] Use binary operator `z = cond and other_cond` instead of `if`-`else`-block
     |
 146 |   # SIM108 - should suggest
 147 |   # z = cond and other_cond
@@ -157,7 +157,7 @@ SIM108.py:148:1: SIM108 [*] Use ternary operator `z = cond if not cond else othe
 152 |
 153 |   # SIM108 - should suggest
     |
-    = help: Replace `if`-`else`-block with `z = cond if not cond else other_cond`
+    = help: Replace `if`-`else`-block with `z = cond and other_cond`
 
 ℹ Unsafe fix
 145 145 | 
@@ -167,12 +167,12 @@ SIM108.py:148:1: SIM108 [*] Use ternary operator `z = cond if not cond else othe
 149     |-    z = cond
 150     |-else:
 151     |-    z = other_cond
-    148 |+z = cond if not cond else other_cond
+    148 |+z = cond and other_cond
 152 149 | 
 153 150 | # SIM108 - should suggest
 154 151 | # z = not cond and other_cond
 
-SIM108.py:155:1: SIM108 [*] Use ternary operator `z = not cond if cond else other_cond` instead of `if`-`else`-block
+SIM108.py:155:1: SIM108 [*] Use binary operator `z = not cond and other_cond` instead of `if`-`else`-block
     |
 153 |   # SIM108 - should suggest
 154 |   # z = not cond and other_cond
@@ -184,7 +184,7 @@ SIM108.py:155:1: SIM108 [*] Use ternary operator `z = not cond if cond else othe
 159 |
 160 |   # SIM108 does not suggest
     |
-    = help: Replace `if`-`else`-block with `z = not cond if cond else other_cond`
+    = help: Replace `if`-`else`-block with `z = not cond and other_cond`
 
 ℹ Unsafe fix
 152 152 | 
@@ -194,7 +194,7 @@ SIM108.py:155:1: SIM108 [*] Use ternary operator `z = not cond if cond else othe
 156     |-    z = not cond
 157     |-else:
 158     |-    z = other_cond
-    155 |+z = not cond if cond else other_cond
+    155 |+z = not cond and other_cond
 159 156 | 
 160 157 | # SIM108 does not suggest
 161 158 | # a binary option in these cases,

crates/ruff_linter/src/rules/flake8_simplify/snapshots/ruff_linter__rules__flake8_simplify__tests__preview__SIM108_SIM108.py.snap

@@ -1,382 +0,0 @@
----
-source: crates/ruff_linter/src/rules/flake8_simplify/mod.rs
----
-SIM108.py:2:1: SIM108 [*] Use ternary operator `b = c if a else d` instead of `if`-`else`-block
-  |
-1 |   # SIM108
-2 | / if a:
-3 | |     b = c
-4 | | else:
-5 | |     b = d
-  | |_________^ SIM108
-6 |
-7 |   # OK
-  |
-  = help: Replace `if`-`else`-block with `b = c if a else d`
-
-ℹ Unsafe fix
-1 1 | # SIM108
-2   |-if a:
-3   |-    b = c
-4   |-else:
-5   |-    b = d
-  2 |+b = c if a else d
-6 3 | 
-7 4 | # OK
-8 5 | b = c if a else d
-
-SIM108.py:30:5: SIM108 [*] Use ternary operator `b = 1 if a else 2` instead of `if`-`else`-block
-   |
-28 |       pass
-29 |   else:
-30 | /     if a:
-31 | |         b = 1
-32 | |     else:
-33 | |         b = 2
-   | |_____________^ SIM108
-   |
-   = help: Replace `if`-`else`-block with `b = 1 if a else 2`
-
-ℹ Unsafe fix
-27 27 | if True:
-28 28 |     pass
-29 29 | else:
-30    |-    if a:
-31    |-        b = 1
-32    |-    else:
-33    |-        b = 2
-   30 |+    b = 1 if a else 2
-34 31 | 
-35 32 | 
-36 33 | import sys
-
-SIM108.py:58:1: SIM108 Use ternary operator `abc = x if x > 0 else -x` instead of `if`-`else`-block
-   |
-57 |   # SIM108 (without fix due to comments)
-58 | / if x > 0:
-59 | |     # test test
-60 | |     abc = x
-61 | | else:
-62 | |     # test test test
-63 | |     abc = -x
-   | |____________^ SIM108
-   |
-   = help: Replace `if`-`else`-block with `abc = x if x > 0 else -x`
-
-SIM108.py:82:1: SIM108 [*] Use ternary operator `b = "cccccccccccccccccccccccccccccccccß" if a else "ddddddddddddddddddddddddddddddddd💣"` instead of `if`-`else`-block
-   |
-81 |   # SIM108
-82 | / if a:
-83 | |     b = "cccccccccccccccccccccccccccccccccß"
-84 | | else:
-85 | |     b = "ddddddddddddddddddddddddddddddddd💣"
-   | |_____________________________________________^ SIM108
-   |
-   = help: Replace `if`-`else`-block with `b = "cccccccccccccccccccccccccccccccccß" if a else "ddddddddddddddddddddddddddddddddd💣"`
-
-ℹ Unsafe fix
-79 79 | 
-80 80 | 
-81 81 | # SIM108
-82    |-if a:
-83    |-    b = "cccccccccccccccccccccccccccccccccß"
-84    |-else:
-85    |-    b = "ddddddddddddddddddddddddddddddddd💣"
-   82 |+b = "cccccccccccccccccccccccccccccccccß" if a else "ddddddddddddddddddddddddddddddddd💣"
-86 83 | 
-87 84 | 
-88 85 | # OK (too long)
-
-SIM108.py:105:1: SIM108 Use ternary operator `exitcode = 0 if True else 1` instead of `if`-`else`-block
-    |
-104 |   # SIM108 (without fix due to trailing comment)
-105 | / if True:
-106 | |     exitcode = 0
-107 | | else:
-108 | |     exitcode = 1  # Trailing comment
-    | |________________^ SIM108
-    |
-    = help: Replace `if`-`else`-block with `exitcode = 0 if True else 1`
-
-SIM108.py:112:1: SIM108 Use ternary operator `x = 3 if True else 5` instead of `if`-`else`-block
-    |
-111 |   # SIM108
-112 | / if True: x = 3  # Foo
-113 | | else: x = 5
-    | |___________^ SIM108
-    |
-    = help: Replace `if`-`else`-block with `x = 3 if True else 5`
-
-SIM108.py:117:1: SIM108 Use ternary operator `x = 3 if True else 5` instead of `if`-`else`-block
-    |
-116 |   # SIM108
-117 | / if True:  # Foo
-118 | |     x = 3
-119 | | else:
-120 | |     x = 5
-    | |_________^ SIM108
-    |
-    = help: Replace `if`-`else`-block with `x = 3 if True else 5`
-
-SIM108.py:141:1: SIM108 [*] Use binary operator `z = cond or other_cond` instead of `if`-`else`-block
-    |
-139 |   # SIM108 - should suggest
-140 |   # z = cond or other_cond
-141 | / if cond:
-142 | |     z = cond 
-143 | | else:
-144 | |     z = other_cond
-    | |__________________^ SIM108
-145 |
-146 |   # SIM108 - should suggest
-    |
-    = help: Replace `if`-`else`-block with `z = cond or other_cond`
-
-ℹ Unsafe fix
-138 138 | 
-139 139 | # SIM108 - should suggest
-140 140 | # z = cond or other_cond
-141     |-if cond:
-142     |-    z = cond 
-143     |-else:
-144     |-    z = other_cond
-    141 |+z = cond or other_cond
-145 142 | 
-146 143 | # SIM108 - should suggest
-147 144 | # z = cond and other_cond
-
-SIM108.py:148:1: SIM108 [*] Use binary operator `z = cond and other_cond` instead of `if`-`else`-block
-    |
-146 |   # SIM108 - should suggest
-147 |   # z = cond and other_cond
-148 | / if not cond:
-149 | |     z = cond
-150 | | else:
-151 | |     z = other_cond
-    | |__________________^ SIM108
-152 |
-153 |   # SIM108 - should suggest
-    |
-    = help: Replace `if`-`else`-block with `z = cond and other_cond`
-
-ℹ Unsafe fix
-145 145 | 
-146 146 | # SIM108 - should suggest
-147 147 | # z = cond and other_cond
-148     |-if not cond:
-149     |-    z = cond
-150     |-else:
-151     |-    z = other_cond
-    148 |+z = cond and other_cond
-152 149 | 
-153 150 | # SIM108 - should suggest
-154 151 | # z = not cond and other_cond
-
-SIM108.py:155:1: SIM108 [*] Use binary operator `z = not cond and other_cond` instead of `if`-`else`-block
-    |
-153 |   # SIM108 - should suggest
-154 |   # z = not cond and other_cond
-155 | / if cond:
-156 | |     z = not cond
-157 | | else:
-158 | |     z = other_cond
-    | |__________________^ SIM108
-159 |
-160 |   # SIM108 does not suggest
-    |
-    = help: Replace `if`-`else`-block with `z = not cond and other_cond`
-
-ℹ Unsafe fix
-152 152 | 
-153 153 | # SIM108 - should suggest
-154 154 | # z = not cond and other_cond
-155     |-if cond:
-156     |-    z = not cond
-157     |-else:
-158     |-    z = other_cond
-    155 |+z = not cond and other_cond
-159 156 | 
-160 157 | # SIM108 does not suggest
-161 158 | # a binary option in these cases,
-
-SIM108.py:167:1: SIM108 [*] Use ternary operator `z = 1 if True else other` instead of `if`-`else`-block
-    |
-165 |   # (Of course, these specific expressions 
-166 |   # should be simplified for other reasons...)
-167 | / if True:
-168 | |     z = 1
-169 | | else:
-170 | |     z = other
-    | |_____________^ SIM108
-171 |
-172 |   if False:
-    |
-    = help: Replace `if`-`else`-block with `z = 1 if True else other`
-
-ℹ Unsafe fix
-164 164 | # so, e.g. `True == 1`.
-165 165 | # (Of course, these specific expressions 
-166 166 | # should be simplified for other reasons...)
-167     |-if True:
-168     |-    z = 1
-169     |-else:
-170     |-    z = other
-    167 |+z = 1 if True else other
-171 168 | 
-172 169 | if False:
-173 170 |     z = 1
-
-SIM108.py:172:1: SIM108 [*] Use ternary operator `z = 1 if False else other` instead of `if`-`else`-block
-    |
-170 |       z = other
-171 |
-172 | / if False:
-173 | |     z = 1
-174 | | else:
-175 | |     z = other
-    | |_____________^ SIM108
-176 |
-177 |   if 1:
-    |
-    = help: Replace `if`-`else`-block with `z = 1 if False else other`
-
-ℹ Unsafe fix
-169 169 | else:
-170 170 |     z = other
-171 171 | 
-172     |-if False:
-173     |-    z = 1
-174     |-else:
-175     |-    z = other
-    172 |+z = 1 if False else other
-176 173 | 
-177 174 | if 1:
-178 175 |     z = True
-
-SIM108.py:177:1: SIM108 [*] Use ternary operator `z = True if 1 else other` instead of `if`-`else`-block
-    |
-175 |       z = other
-176 |
-177 | / if 1:
-178 | |     z = True
-179 | | else:
-180 | |     z = other
-    | |_____________^ SIM108
-181 |
-182 |   # SIM108 does not suggest a binary option in this
-    |
-    = help: Replace `if`-`else`-block with `z = True if 1 else other`
-
-ℹ Unsafe fix
-174 174 | else:
-175 175 |     z = other
-176 176 | 
-177     |-if 1:
-178     |-    z = True
-179     |-else:
-180     |-    z = other
-    177 |+z = True if 1 else other
-181 178 | 
-182 179 | # SIM108 does not suggest a binary option in this
-183 180 | # case, since we'd be reducing the number of calls
-
-SIM108.py:185:1: SIM108 [*] Use ternary operator `z = foo() if foo() else other` instead of `if`-`else`-block
-    |
-183 |   # case, since we'd be reducing the number of calls
-184 |   # from Two to one.
-185 | / if foo():
-186 | |     z = foo()
-187 | | else:
-188 | |     z = other
-    | |_____________^ SIM108
-189 |
-190 |   # SIM108 does not suggest a binary option in this
-    |
-    = help: Replace `if`-`else`-block with `z = foo() if foo() else other`
-
-ℹ Unsafe fix
-182 182 | # SIM108 does not suggest a binary option in this
-183 183 | # case, since we'd be reducing the number of calls
-184 184 | # from Two to one.
-185     |-if foo():
-186     |-    z = foo()
-187     |-else:
-188     |-    z = other
-    185 |+z = foo() if foo() else other
-189 186 | 
-190 187 | # SIM108 does not suggest a binary option in this
-191 188 | # case, since we'd be reducing the number of calls
-
-SIM108.py:193:1: SIM108 [*] Use ternary operator `z = not foo() if foo() else other` instead of `if`-`else`-block
-    |
-191 |   # case, since we'd be reducing the number of calls
-192 |   # from Two to one.
-193 | / if foo():
-194 | |     z = not foo()
-195 | | else:
-196 | |     z = other
-    | |_____________^ SIM108
-    |
-    = help: Replace `if`-`else`-block with `z = not foo() if foo() else other`
-
-ℹ Unsafe fix
-190 190 | # SIM108 does not suggest a binary option in this
-191 191 | # case, since we'd be reducing the number of calls
-192 192 | # from Two to one.
-193     |-if foo():
-194     |-    z = not foo()
-195     |-else:
-196     |-    z = other
-    193 |+z = not foo() if foo() else other
-197 194 | 
-198 195 | 
-199 196 | # These two cases double as tests for f-string quote preservation. The first
-
-SIM108.py:202:1: SIM108 [*] Use ternary operator `var = "str" if cond else f"{first}-{second}"` instead of `if`-`else`-block
-    |
-200 |   # f-string should preserve its double quotes, and the second should preserve
-201 |   # single quotes
-202 | / if cond:
-203 | |     var = "str"
-204 | | else:
-205 | |     var = f"{first}-{second}"
-    | |_____________________________^ SIM108
-206 |
-207 |   if cond:
-    |
-    = help: Replace `if`-`else`-block with `var = "str" if cond else f"{first}-{second}"`
-
-ℹ Unsafe fix
-199 199 | # These two cases double as tests for f-string quote preservation. The first
-200 200 | # f-string should preserve its double quotes, and the second should preserve
-201 201 | # single quotes
-202     |-if cond:
-203     |-    var = "str"
-204     |-else:
-205     |-    var = f"{first}-{second}"
-    202 |+var = "str" if cond else f"{first}-{second}"
-206 203 | 
-207 204 | if cond:
-208 205 |     var = "str"
-
-SIM108.py:207:1: SIM108 [*] Use ternary operator `var = "str" if cond else f'{first}-{second}'` instead of `if`-`else`-block
-    |
-205 |       var = f"{first}-{second}"
-206 |
-207 | / if cond:
-208 | |     var = "str"
-209 | | else:
-210 | |     var = f'{first}-{second}'
-    | |_____________________________^ SIM108
-    |
-    = help: Replace `if`-`else`-block with `var = "str" if cond else f'{first}-{second}'`
-
-ℹ Unsafe fix
-204 204 | else:
-205 205 |     var = f"{first}-{second}"
-206 206 | 
-207     |-if cond:
-208     |-    var = "str"
-209     |-else:
-210     |-    var = f'{first}-{second}'
-    207 |+var = "str" if cond else f'{first}-{second}'

crates/ruff_linter/src/rules/flake8_todos/mod.rs

@@ -2,7 +2,6 @@ pub(crate) mod rules;
 
 #[cfg(test)]
 mod tests {
-    use std::convert::AsRef;
     use std::path::Path;
 
     use anyhow::Result;
@@ -20,7 +19,7 @@ mod tests {
     #[test_case(Rule::InvalidTodoCapitalization, Path::new("TD006.py"))]
     #[test_case(Rule::MissingSpaceAfterTodoColon, Path::new("TD007.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_todos").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),

crates/ruff_linter/src/rules/flake8_type_checking/mod.rs

@@ -6,7 +6,6 @@ pub mod settings;
 
 #[cfg(test)]
 mod tests {
-    use std::convert::AsRef;
     use std::path::Path;
 
     use anyhow::Result;
@@ -55,7 +54,7 @@ mod tests {
     #[test_case(Rule::TypingOnlyThirdPartyImport, Path::new("typing_modules_1.py"))]
     #[test_case(Rule::TypingOnlyThirdPartyImport, Path::new("typing_modules_2.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),
@@ -70,7 +69,7 @@ mod tests {
     #[test_case(Rule::QuotedTypeAlias, Path::new("TC008.py"))]
     #[test_case(Rule::QuotedTypeAlias, Path::new("TC008_typing_execution_context.py"))]
     fn type_alias_rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings::for_rules(vec![
@@ -84,11 +83,7 @@ mod tests {
 
     #[test_case(Rule::QuotedTypeAlias, Path::new("TC008_union_syntax_pre_py310.py"))]
     fn type_alias_rules_pre_py310(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!(
-            "pre_py310_{}_{}",
-            rule_code.as_ref(),
-            path.to_string_lossy()
-        );
+        let snapshot = format!("pre_py310_{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings {
@@ -107,7 +102,7 @@ mod tests {
     #[test_case(Rule::RuntimeImportInTypeCheckingBlock, Path::new("quote3.py"))]
     #[test_case(Rule::TypingOnlyThirdPartyImport, Path::new("quote3.py"))]
     fn quote(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("quote_{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("quote_{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings {
@@ -126,7 +121,7 @@ mod tests {
     #[test_case(Rule::TypingOnlyStandardLibraryImport, Path::new("init_var.py"))]
     #[test_case(Rule::TypingOnlyStandardLibraryImport, Path::new("kw_only.py"))]
     fn strict(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("strict_{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("strict_{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings {
@@ -170,7 +165,7 @@ mod tests {
         Path::new("exempt_type_checking_3.py")
     )]
     fn exempt_type_checking(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings {
@@ -207,7 +202,7 @@ mod tests {
         Path::new("runtime_evaluated_base_classes_5.py")
     )]
     fn runtime_evaluated_base_classes(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings {
@@ -238,7 +233,7 @@ mod tests {
         Path::new("runtime_evaluated_decorators_3.py")
     )]
     fn runtime_evaluated_decorators(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings {
@@ -264,7 +259,7 @@ mod tests {
         Path::new("module/undefined.py")
     )]
     fn base_class_same_file(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings {
@@ -282,7 +277,7 @@ mod tests {
     #[test_case(Rule::RuntimeImportInTypeCheckingBlock, Path::new("module/app.py"))]
     #[test_case(Rule::TypingOnlyStandardLibraryImport, Path::new("module/routes.py"))]
     fn decorator_same_file(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_type_checking").join(path).as_path(),
             &settings::LinterSettings {

crates/ruff_linter/src/rules/numpy/mod.rs

@@ -4,7 +4,6 @@ pub(crate) mod rules;
 
 #[cfg(test)]
 mod tests {
-    use std::convert::AsRef;
     use std::path::Path;
 
     use anyhow::Result;
@@ -22,7 +21,7 @@ mod tests {
     #[test_case(Rule::Numpy2Deprecation, Path::new("NPY201_2.py"))]
     #[test_case(Rule::Numpy2Deprecation, Path::new("NPY201_3.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("numpy").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),

crates/ruff_linter/src/rules/pydoclint/mod.rs

@@ -4,7 +4,6 @@ pub mod settings;
 
 #[cfg(test)]
 mod tests {
-    use std::convert::AsRef;
     use std::path::Path;
 
     use anyhow::Result;
@@ -20,7 +19,7 @@ mod tests {
 
     #[test_case(Rule::DocstringMissingException, Path::new("DOC501.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("pydoclint").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),
@@ -36,7 +35,7 @@ mod tests {
     #[test_case(Rule::DocstringMissingException, Path::new("DOC501_google.py"))]
     #[test_case(Rule::DocstringExtraneousException, Path::new("DOC502_google.py"))]
     fn rules_google_style(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("pydoclint").join(path).as_path(),
             &settings::LinterSettings {
@@ -58,7 +57,7 @@ mod tests {
     #[test_case(Rule::DocstringMissingException, Path::new("DOC501_numpy.py"))]
     #[test_case(Rule::DocstringExtraneousException, Path::new("DOC502_numpy.py"))]
     fn rules_numpy_style(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("pydoclint").join(path).as_path(),
             &settings::LinterSettings {
@@ -79,7 +78,7 @@ mod tests {
     fn rules_google_style_ignore_one_line(rule_code: Rule, path: &Path) -> Result<()> {
         let snapshot = format!(
             "{}_{}_ignore_one_line",
-            rule_code.as_ref(),
+            rule_code.name(),
             path.to_string_lossy()
         );
         let diagnostics = test_path(

crates/ruff_linter/src/rules/pyflakes/mod.rs

@@ -776,8 +776,10 @@ mod tests {
         messages.sort_by_key(Ranged::start);
         let actual = messages
             .iter()
-            .filter_map(Message::to_rule)
+            .filter(|msg| !msg.is_syntax_error())
+            .map(Message::name)
             .collect::<Vec<_>>();
+        let expected: Vec<_> = expected.iter().map(|rule| rule.name().as_str()).collect();
         assert_eq!(actual, expected);
     }
 

crates/ruff_linter/src/rules/pyupgrade/rules/deprecated_import.rs

@@ -271,7 +271,7 @@ const TYPING_TO_RE_39: &[&str] = &["Match", "Pattern"];
 const TYPING_RE_TO_RE_39: &[&str] = &["Match", "Pattern"];
 
 // Members of `typing_extensions` that were moved to `typing`.
-const TYPING_EXTENSIONS_TO_TYPING_39: &[&str] = &["Annotated", "get_type_hints"];
+const TYPING_EXTENSIONS_TO_TYPING_39: &[&str] = &["Annotated"];
 
 // Members of `typing` that were moved _and_ renamed (and thus cannot be
 // automatically fixed).
@@ -373,6 +373,9 @@ const TYPING_EXTENSIONS_TO_TYPING_313: &[&str] = &[
     "NoDefault",
     "ReadOnly",
     "TypeIs",
+    // Introduced in Python 3.5,
+    // but typing_extensions backports features from py313:
+    "get_type_hints",
     // Introduced in Python 3.6,
     // but typing_extensions backports features from py313:
     "ContextManager",

crates/ruff_linter/src/rules/pyupgrade/snapshots/ruff_linter__rules__pyupgrade__tests__UP035.py.snap

@@ -1179,6 +1179,8 @@ UP035.py:111:1: UP035 [*] Import from `warnings` instead: `deprecated`
 110 | # UP035 on py313+ only
 111 | from typing_extensions import deprecated
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ UP035
+112 |
+113 | # UP035 on py313+ only
     |
     = help: Import from `warnings`
 
@@ -1189,5 +1191,25 @@ UP035.py:111:1: UP035 [*] Import from `warnings` instead: `deprecated`
 111     |-from typing_extensions import deprecated
     111 |+from warnings import deprecated
 112 112 | 
-113 113 | 
-114 114 | # https://github.com/astral-sh/ruff/issues/15780
+113 113 | # UP035 on py313+ only
+114 114 | from typing_extensions import get_type_hints
+
+UP035.py:114:1: UP035 [*] Import from `typing` instead: `get_type_hints`
+    |
+113 | # UP035 on py313+ only
+114 | from typing_extensions import get_type_hints
+    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ UP035
+115 |
+116 | # https://github.com/astral-sh/ruff/issues/15780
+    |
+    = help: Import from `typing`
+
+ℹ Safe fix
+111 111 | from typing_extensions import deprecated
+112 112 | 
+113 113 | # UP035 on py313+ only
+114     |-from typing_extensions import get_type_hints
+    114 |+from typing import get_type_hints
+115 115 | 
+116 116 | # https://github.com/astral-sh/ruff/issues/15780
+117 117 | from typing_extensions import is_typeddict

crates/ruff_linter/src/rules/refurb/mod.rs

@@ -62,24 +62,6 @@ mod tests {
         Ok(())
     }
 
-    #[test_case(Rule::ReadlinesInFor, Path::new("FURB129.py"))]
-    fn preview(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!(
-            "preview__{}_{}",
-            rule_code.noqa_code(),
-            path.to_string_lossy()
-        );
-        let diagnostics = test_path(
-            Path::new("refurb").join(path).as_path(),
-            &settings::LinterSettings {
-                preview: settings::types::PreviewMode::Enabled,
-                ..settings::LinterSettings::for_rule(rule_code)
-            },
-        )?;
-        assert_messages!(snapshot, diagnostics);
-        Ok(())
-    }
-
     #[test]
     fn write_whole_file_python_39() -> Result<()> {
         let diagnostics = test_path(

crates/ruff_linter/src/rules/refurb/rules/readlines_in_for.rs

@@ -6,7 +6,7 @@ use ruff_python_semantic::analyze::typing::is_io_base_expr;
 use ruff_text_size::Ranged;
 
 use crate::checkers::ast::Checker;
-use crate::preview::is_readlines_in_for_fix_safe_enabled;
+use crate::fix::edits::pad_end;
 use crate::{AlwaysFixableViolation, Edit, Fix};
 
 /// ## What it does
@@ -85,21 +85,25 @@ fn readlines_in_iter(checker: &Checker, iter_expr: &Expr) {
             return;
         }
     }
-    let edit = if let Some(parenthesized_range) = parenthesized_range(
+
+    let deletion_range = if let Some(parenthesized_range) = parenthesized_range(
         expr_attr.value.as_ref().into(),
         expr_attr.into(),
         checker.comment_ranges(),
         checker.source(),
     ) {
-        Edit::range_deletion(expr_call.range().add_start(parenthesized_range.len()))
+        expr_call.range().add_start(parenthesized_range.len())
     } else {
-        Edit::range_deletion(expr_call.range().add_start(expr_attr.value.range().len()))
+        expr_call.range().add_start(expr_attr.value.range().len())
+    };
+
+    let padded = pad_end(String::new(), deletion_range.end(), checker.locator());
+    let edit = if padded.is_empty() {
+        Edit::range_deletion(deletion_range)
+    } else {
+        Edit::range_replacement(padded, deletion_range)
     };
 
     let mut diagnostic = checker.report_diagnostic(ReadlinesInFor, expr_call.range());
-    diagnostic.set_fix(if is_readlines_in_for_fix_safe_enabled(checker.settings) {
-        Fix::safe_edit(edit)
-    } else {
-        Fix::unsafe_edit(edit)
-    });
+    diagnostic.set_fix(Fix::safe_edit(edit));
 }

crates/ruff_linter/src/rules/refurb/snapshots/ruff_linter__rules__refurb__tests__FURB129_FURB129.py.snap

@@ -12,7 +12,7 @@ FURB129.py:7:18: FURB129 [*] Instead of calling `readlines()`, iterate over file
   |
   = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 4 4 | 
 5 5 | # Errors
 6 6 | with open("FURB129.py") as f:
@@ -33,7 +33,7 @@ FURB129.py:9:35: FURB129 [*] Instead of calling `readlines()`, iterate over file
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 6  6  | with open("FURB129.py") as f:
 7  7  |     for _line in f.readlines():
 8  8  |         pass
@@ -53,7 +53,7 @@ FURB129.py:10:35: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 7  7  |     for _line in f.readlines():
 8  8  |         pass
 9  9  |     a = [line.lower() for line in f.readlines()]
@@ -74,7 +74,7 @@ FURB129.py:11:49: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 8  8  |         pass
 9  9  |     a = [line.lower() for line in f.readlines()]
 10 10 |     b = {line.upper() for line in f.readlines()}
@@ -93,7 +93,7 @@ FURB129.py:14:18: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 11 11 |     c = {line.lower(): line.upper() for line in f.readlines()}
 12 12 | 
 13 13 | with Path("FURB129.py").open() as f:
@@ -113,7 +113,7 @@ FURB129.py:17:14: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 14 14 |     for _line in f.readlines():
 15 15 |         pass
 16 16 | 
@@ -133,7 +133,7 @@ FURB129.py:20:14: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 17 17 | for _line in open("FURB129.py").readlines():
 18 18 |     pass
 19 19 | 
@@ -154,7 +154,7 @@ FURB129.py:26:18: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 23 23 | 
 24 24 | def func():
 25 25 |     f = Path("FURB129.py").open()
@@ -173,7 +173,7 @@ FURB129.py:32:18: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 29 29 | 
 30 30 | 
 31 31 | def func(f: io.BytesIO):
@@ -194,7 +194,7 @@ FURB129.py:38:22: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 35 35 | 
 36 36 | def func():
 37 37 |     with (open("FURB129.py") as f, foo as bar):
@@ -213,7 +213,7 @@ FURB129.py:47:17: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 44 44 | import builtins
 45 45 | 
 46 46 | with builtins.open("FURB129.py") as f:
@@ -232,7 +232,7 @@ FURB129.py:54:17: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 51 51 | from builtins import open as o
 52 52 | 
 53 53 | with o("FURB129.py") as f:
@@ -252,7 +252,7 @@ FURB129.py:93:17: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 90 90 | 
 91 91 | # https://github.com/astral-sh/ruff/issues/18231
 92 92 | with open("furb129.py") as f:
@@ -270,7 +270,7 @@ FURB129.py:97:23: FURB129 [*] Instead of calling `readlines()`, iterate over fil
    |
    = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 94 94 |         pass
 95 95 | 
 96 96 | with open("furb129.py") as f:
@@ -290,7 +290,7 @@ FURB129.py:101:17: FURB129 [*] Instead of calling `readlines()`, iterate over fi
     |
     = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 98  98  | 
 99  99  | 
 100 100 | with open("furb129.py") as f:
@@ -310,10 +310,27 @@ FURB129.py:103:16: FURB129 [*] Instead of calling `readlines()`, iterate over fi
     |
     = help: Remove `readlines()`
 
-ℹ Unsafe fix
+ℹ Safe fix
 100 100 | with open("furb129.py") as f:
 101 101 |     for line in (((f))).readlines():
 102 102 |         pass
 103     |-    for line in(f).readlines():
     103 |+    for line in(f):
 104 104 |         pass
+105 105 | 
+106 106 |     # Test case for issue #17683 (missing space before keyword)
+
+FURB129.py:107:29: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
+    |
+106 |     # Test case for issue #17683 (missing space before keyword)
+107 |     print([line for line in f.readlines()if True])
+    |                             ^^^^^^^^^^^^^ FURB129
+    |
+    = help: Remove `readlines()`
+
+ℹ Safe fix
+104 104 |         pass
+105 105 | 
+106 106 |     # Test case for issue #17683 (missing space before keyword)
+107     |-    print([line for line in f.readlines()if True])
+    107 |+    print([line for line in f if True])

crates/ruff_linter/src/rules/refurb/snapshots/ruff_linter__rules__refurb__tests__preview__FURB129_FURB129.py.snap

@@ -1,319 +0,0 @@
----
-source: crates/ruff_linter/src/rules/refurb/mod.rs
----
-FURB129.py:7:18: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-  |
-5 | # Errors
-6 | with open("FURB129.py") as f:
-7 |     for _line in f.readlines():
-  |                  ^^^^^^^^^^^^^ FURB129
-8 |         pass
-9 |     a = [line.lower() for line in f.readlines()]
-  |
-  = help: Remove `readlines()`
-
-ℹ Safe fix
-4 4 | 
-5 5 | # Errors
-6 6 | with open("FURB129.py") as f:
-7   |-    for _line in f.readlines():
-  7 |+    for _line in f:
-8 8 |         pass
-9 9 |     a = [line.lower() for line in f.readlines()]
-10 10 |     b = {line.upper() for line in f.readlines()}
-
-FURB129.py:9:35: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
- 7 |     for _line in f.readlines():
- 8 |         pass
- 9 |     a = [line.lower() for line in f.readlines()]
-   |                                   ^^^^^^^^^^^^^ FURB129
-10 |     b = {line.upper() for line in f.readlines()}
-11 |     c = {line.lower(): line.upper() for line in f.readlines()}
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-6  6  | with open("FURB129.py") as f:
-7  7  |     for _line in f.readlines():
-8  8  |         pass
-9     |-    a = [line.lower() for line in f.readlines()]
-   9  |+    a = [line.lower() for line in f]
-10 10 |     b = {line.upper() for line in f.readlines()}
-11 11 |     c = {line.lower(): line.upper() for line in f.readlines()}
-12 12 | 
-
-FURB129.py:10:35: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
- 8 |         pass
- 9 |     a = [line.lower() for line in f.readlines()]
-10 |     b = {line.upper() for line in f.readlines()}
-   |                                   ^^^^^^^^^^^^^ FURB129
-11 |     c = {line.lower(): line.upper() for line in f.readlines()}
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-7  7  |     for _line in f.readlines():
-8  8  |         pass
-9  9  |     a = [line.lower() for line in f.readlines()]
-10    |-    b = {line.upper() for line in f.readlines()}
-   10 |+    b = {line.upper() for line in f}
-11 11 |     c = {line.lower(): line.upper() for line in f.readlines()}
-12 12 | 
-13 13 | with Path("FURB129.py").open() as f:
-
-FURB129.py:11:49: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
- 9 |     a = [line.lower() for line in f.readlines()]
-10 |     b = {line.upper() for line in f.readlines()}
-11 |     c = {line.lower(): line.upper() for line in f.readlines()}
-   |                                                 ^^^^^^^^^^^^^ FURB129
-12 |
-13 | with Path("FURB129.py").open() as f:
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-8  8  |         pass
-9  9  |     a = [line.lower() for line in f.readlines()]
-10 10 |     b = {line.upper() for line in f.readlines()}
-11    |-    c = {line.lower(): line.upper() for line in f.readlines()}
-   11 |+    c = {line.lower(): line.upper() for line in f}
-12 12 | 
-13 13 | with Path("FURB129.py").open() as f:
-14 14 |     for _line in f.readlines():
-
-FURB129.py:14:18: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-13 | with Path("FURB129.py").open() as f:
-14 |     for _line in f.readlines():
-   |                  ^^^^^^^^^^^^^ FURB129
-15 |         pass
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-11 11 |     c = {line.lower(): line.upper() for line in f.readlines()}
-12 12 | 
-13 13 | with Path("FURB129.py").open() as f:
-14    |-    for _line in f.readlines():
-   14 |+    for _line in f:
-15 15 |         pass
-16 16 | 
-17 17 | for _line in open("FURB129.py").readlines():
-
-FURB129.py:17:14: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-15 |         pass
-16 |
-17 | for _line in open("FURB129.py").readlines():
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB129
-18 |     pass
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-14 14 |     for _line in f.readlines():
-15 15 |         pass
-16 16 | 
-17    |-for _line in open("FURB129.py").readlines():
-   17 |+for _line in open("FURB129.py"):
-18 18 |     pass
-19 19 | 
-20 20 | for _line in Path("FURB129.py").open().readlines():
-
-FURB129.py:20:14: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-18 |     pass
-19 |
-20 | for _line in Path("FURB129.py").open().readlines():
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ FURB129
-21 |     pass
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-17 17 | for _line in open("FURB129.py").readlines():
-18 18 |     pass
-19 19 | 
-20    |-for _line in Path("FURB129.py").open().readlines():
-   20 |+for _line in Path("FURB129.py").open():
-21 21 |     pass
-22 22 | 
-23 23 | 
-
-FURB129.py:26:18: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-24 | def func():
-25 |     f = Path("FURB129.py").open()
-26 |     for _line in f.readlines():
-   |                  ^^^^^^^^^^^^^ FURB129
-27 |         pass
-28 |     f.close()
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-23 23 | 
-24 24 | def func():
-25 25 |     f = Path("FURB129.py").open()
-26    |-    for _line in f.readlines():
-   26 |+    for _line in f:
-27 27 |         pass
-28 28 |     f.close()
-29 29 | 
-
-FURB129.py:32:18: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-31 | def func(f: io.BytesIO):
-32 |     for _line in f.readlines():
-   |                  ^^^^^^^^^^^^^ FURB129
-33 |         pass
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-29 29 | 
-30 30 | 
-31 31 | def func(f: io.BytesIO):
-32    |-    for _line in f.readlines():
-   32 |+    for _line in f:
-33 33 |         pass
-34 34 | 
-35 35 | 
-
-FURB129.py:38:22: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-36 | def func():
-37 |     with (open("FURB129.py") as f, foo as bar):
-38 |         for _line in f.readlines():
-   |                      ^^^^^^^^^^^^^ FURB129
-39 |             pass
-40 |         for _line in bar.readlines():
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-35 35 | 
-36 36 | def func():
-37 37 |     with (open("FURB129.py") as f, foo as bar):
-38    |-        for _line in f.readlines():
-   38 |+        for _line in f:
-39 39 |             pass
-40 40 |         for _line in bar.readlines():
-41 41 |             pass
-
-FURB129.py:47:17: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-46 | with builtins.open("FURB129.py") as f:
-47 |     for line in f.readlines():
-   |                 ^^^^^^^^^^^^^ FURB129
-48 |         pass
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-44 44 | import builtins
-45 45 | 
-46 46 | with builtins.open("FURB129.py") as f:
-47    |-    for line in f.readlines():
-   47 |+    for line in f:
-48 48 |         pass
-49 49 | 
-50 50 | 
-
-FURB129.py:54:17: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-53 | with o("FURB129.py") as f:
-54 |     for line in f.readlines():
-   |                 ^^^^^^^^^^^^^ FURB129
-55 |         pass
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-51 51 | from builtins import open as o
-52 52 | 
-53 53 | with o("FURB129.py") as f:
-54    |-    for line in f.readlines():
-   54 |+    for line in f:
-55 55 |         pass
-56 56 | 
-57 57 | 
-
-FURB129.py:93:17: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-91 | # https://github.com/astral-sh/ruff/issues/18231
-92 | with open("furb129.py") as f:
-93 |     for line in (f).readlines():
-   |                 ^^^^^^^^^^^^^^^ FURB129
-94 |         pass
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-90 90 | 
-91 91 | # https://github.com/astral-sh/ruff/issues/18231
-92 92 | with open("furb129.py") as f:
-93    |-    for line in (f).readlines():
-   93 |+    for line in (f):
-94 94 |         pass
-95 95 | 
-96 96 | with open("furb129.py") as f:
-
-FURB129.py:97:23: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-   |
-96 | with open("furb129.py") as f:
-97 |     [line for line in (f).readlines()]
-   |                       ^^^^^^^^^^^^^^^ FURB129
-   |
-   = help: Remove `readlines()`
-
-ℹ Safe fix
-94 94 |         pass
-95 95 | 
-96 96 | with open("furb129.py") as f:
-97    |-    [line for line in (f).readlines()]
-   97 |+    [line for line in (f)]
-98 98 | 
-99 99 | 
-100 100 | with open("furb129.py") as f:
-
-FURB129.py:101:17: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-    |
-100 | with open("furb129.py") as f:
-101 |     for line in (((f))).readlines():
-    |                 ^^^^^^^^^^^^^^^^^^^ FURB129
-102 |         pass
-103 |     for line in(f).readlines():
-    |
-    = help: Remove `readlines()`
-
-ℹ Safe fix
-98  98  | 
-99  99  | 
-100 100 | with open("furb129.py") as f:
-101     |-    for line in (((f))).readlines():
-    101 |+    for line in (((f))):
-102 102 |         pass
-103 103 |     for line in(f).readlines():
-104 104 |         pass
-
-FURB129.py:103:16: FURB129 [*] Instead of calling `readlines()`, iterate over file object directly
-    |
-101 |     for line in (((f))).readlines():
-102 |         pass
-103 |     for line in(f).readlines():
-    |                ^^^^^^^^^^^^^^^ FURB129
-104 |         pass
-    |
-    = help: Remove `readlines()`
-
-ℹ Safe fix
-100 100 | with open("furb129.py") as f:
-101 101 |     for line in (((f))).readlines():
-102 102 |         pass
-103     |-    for line in(f).readlines():
-    103 |+    for line in(f):
-104 104 |         pass

crates/ruff_linter/src/rules/ruff/mod.rs

@@ -24,6 +24,7 @@ mod tests {
     use crate::{assert_messages, settings};
 
     #[test_case(Rule::CollectionLiteralConcatenation, Path::new("RUF005.py"))]
+    #[test_case(Rule::CollectionLiteralConcatenation, Path::new("RUF005_slices.py"))]
     #[test_case(Rule::AsyncioDanglingTask, Path::new("RUF006.py"))]
     #[test_case(Rule::ZipInsteadOfPairwise, Path::new("RUF007.py"))]
     #[test_case(Rule::MutableDataclassDefault, Path::new("RUF008.py"))]
@@ -94,6 +95,7 @@ mod tests {
     #[test_case(Rule::MapIntVersionParsing, Path::new("RUF048_1.py"))]
     #[test_case(Rule::IfKeyInDictDel, Path::new("RUF051.py"))]
     #[test_case(Rule::UsedDummyVariable, Path::new("RUF052.py"))]
+    #[test_case(Rule::ClassWithMixedTypeVars, Path::new("RUF053.py"))]
     #[test_case(Rule::FalsyDictGetFallback, Path::new("RUF056.py"))]
     #[test_case(Rule::UnusedUnpackedVariable, Path::new("RUF059_0.py"))]
     #[test_case(Rule::UnusedUnpackedVariable, Path::new("RUF059_1.py"))]
@@ -322,10 +324,7 @@ mod tests {
     fn ruff_noqa_filedirective_unused() -> Result<()> {
         let diagnostics = test_path(
             Path::new("ruff/RUF100_6.py"),
-            &settings::LinterSettings {
-                preview: PreviewMode::Enabled,
-                ..settings::LinterSettings::for_rules(vec![Rule::UnusedNOQA])
-            },
+            &settings::LinterSettings::for_rules(vec![Rule::UnusedNOQA]),
         )?;
         assert_messages!(diagnostics);
         Ok(())
@@ -335,15 +334,12 @@ mod tests {
     fn ruff_noqa_filedirective_unused_last_of_many() -> Result<()> {
         let diagnostics = test_path(
             Path::new("ruff/RUF100_7.py"),
-            &settings::LinterSettings {
-                preview: PreviewMode::Enabled,
-                ..settings::LinterSettings::for_rules(vec![
-                    Rule::UnusedNOQA,
-                    Rule::FStringMissingPlaceholders,
-                    Rule::LineTooLong,
-                    Rule::UnusedVariable,
-                ])
-            },
+            &settings::LinterSettings::for_rules(vec![
+                Rule::UnusedNOQA,
+                Rule::FStringMissingPlaceholders,
+                Rule::LineTooLong,
+                Rule::UnusedVariable,
+            ]),
         )?;
         assert_messages!(diagnostics);
         Ok(())
@@ -480,10 +476,8 @@ mod tests {
     #[test_case(Rule::DataclassEnum, Path::new("RUF049.py"))]
     #[test_case(Rule::StarmapZip, Path::new("RUF058_0.py"))]
     #[test_case(Rule::StarmapZip, Path::new("RUF058_1.py"))]
-    #[test_case(Rule::ClassWithMixedTypeVars, Path::new("RUF053.py"))]
     #[test_case(Rule::IndentedFormFeed, Path::new("RUF054.py"))]
     #[test_case(Rule::ImplicitClassVarInDataclass, Path::new("RUF045.py"))]
-    #[test_case(Rule::CollectionLiteralConcatenation, Path::new("RUF005_slices.py"))]
     fn preview_rules(rule_code: Rule, path: &Path) -> Result<()> {
         let snapshot = format!(
             "preview__{}_{}",

crates/ruff_linter/src/rules/ruff/rules/collection_literal_concatenation.rs

@@ -4,7 +4,6 @@ use ruff_text_size::{Ranged, TextRange};
 
 use crate::checkers::ast::Checker;
 use crate::fix::snippet::SourceCodeSnippet;
-use crate::preview::is_support_slices_in_literal_concatenation_enabled;
 use crate::{Edit, Fix, FixAvailability, Violation};
 
 /// ## What it does
@@ -96,7 +95,7 @@ enum Type {
 }
 
 /// Recursively merge all the tuples and lists in the expression.
-fn concatenate_expressions(expr: &Expr, should_support_slices: bool) -> Option<(Expr, Type)> {
+fn concatenate_expressions(expr: &Expr) -> Option<(Expr, Type)> {
     let Expr::BinOp(ast::ExprBinOp {
         left,
         op: Operator::Add,
@@ -108,22 +107,18 @@ fn concatenate_expressions(expr: &Expr, should_support_slices: bool) -> Option<(
     };
 
     let new_left = match left.as_ref() {
-        Expr::BinOp(ast::ExprBinOp { .. }) => {
-            match concatenate_expressions(left, should_support_slices) {
-                Some((new_left, _)) => new_left,
-                None => *left.clone(),
-            }
-        }
+        Expr::BinOp(ast::ExprBinOp { .. }) => match concatenate_expressions(left) {
+            Some((new_left, _)) => new_left,
+            None => *left.clone(),
+        },
         _ => *left.clone(),
     };
 
     let new_right = match right.as_ref() {
-        Expr::BinOp(ast::ExprBinOp { .. }) => {
-            match concatenate_expressions(right, should_support_slices) {
-                Some((new_right, _)) => new_right,
-                None => *right.clone(),
-            }
-        }
+        Expr::BinOp(ast::ExprBinOp { .. }) => match concatenate_expressions(right) {
+            Some((new_right, _)) => new_right,
+            None => *right.clone(),
+        },
         _ => *right.clone(),
     };
 
@@ -151,9 +146,7 @@ fn concatenate_expressions(expr: &Expr, should_support_slices: bool) -> Option<(
             make_splat_elts(splat_element, other_elements, splat_at_left)
         }
         // Subscripts are also considered safe-ish to splat if the indexer is a slice.
-        Expr::Subscript(ast::ExprSubscript { slice, .. })
-            if should_support_slices && matches!(&**slice, Expr::Slice(_)) =>
-        {
+        Expr::Subscript(ast::ExprSubscript { slice, .. }) if matches!(&**slice, Expr::Slice(_)) => {
             make_splat_elts(splat_element, other_elements, splat_at_left)
         }
         // If the splat element is itself a list/tuple, insert them in the other list/tuple.
@@ -198,10 +191,7 @@ pub(crate) fn collection_literal_concatenation(checker: &Checker, expr: &Expr) {
         return;
     }
 
-    let should_support_slices =
-        is_support_slices_in_literal_concatenation_enabled(checker.settings);
-
-    let Some((new_expr, type_)) = concatenate_expressions(expr, should_support_slices) else {
+    let Some((new_expr, type_)) = concatenate_expressions(expr) else {
         return;
     };
 

crates/ruff_linter/src/rules/ruff/rules/unused_async.rs

@@ -7,6 +7,7 @@ use ruff_python_semantic::analyze::function_type::is_stub;
 
 use crate::Violation;
 use crate::checkers::ast::Checker;
+
 use crate::rules::fastapi::rules::is_fastapi_route;
 
 /// ## What it does

crates/ruff_linter/src/rules/tryceratops/mod.rs

@@ -4,7 +4,6 @@ pub(crate) mod rules;
 
 #[cfg(test)]
 mod tests {
-    use std::convert::AsRef;
     use std::path::Path;
 
     use anyhow::Result;
@@ -25,7 +24,7 @@ mod tests {
     #[test_case(Rule::ErrorInsteadOfException, Path::new("TRY400.py"))]
     #[test_case(Rule::VerboseLogMessage, Path::new("TRY401.py"))]
     fn rules(rule_code: Rule, path: &Path) -> Result<()> {
-        let snapshot = format!("{}_{}", rule_code.as_ref(), path.to_string_lossy());
+        let snapshot = format!("{}_{}", rule_code.name(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("tryceratops").join(path).as_path(),
             &settings::LinterSettings::for_rule(rule_code),

crates/ruff_linter/src/test.rs

@@ -20,6 +20,7 @@ use ruff_python_parser::{ParseError, ParseOptions};
 use ruff_python_trivia::textwrap::dedent;
 use ruff_source_file::SourceFileBuilder;
 
+use crate::codes::Rule;
 use crate::fix::{FixResult, fix_file};
 use crate::linter::check_path;
 use crate::message::{Emitter, EmitterContext, Message, TextEmitter};
@@ -233,8 +234,9 @@ Source with applied fixes:
 
     let messages = messages
         .into_iter()
-        .filter_map(|msg| Some((msg.to_rule()?, msg)))
-        .map(|(rule, mut diagnostic)| {
+        .filter_map(|msg| Some((msg.noqa_code()?, msg)))
+        .map(|(code, mut diagnostic)| {
+            let rule = Rule::from_code(&code.to_string()).unwrap();
             let fixable = diagnostic.fix().is_some_and(|fix| {
                 matches!(
                     fix.applicability(),

crates/ruff_macros/src/map_codes.rs

@@ -174,7 +174,7 @@ pub(crate) fn map_codes(func: &ItemFn) -> syn::Result<TokenStream> {
 
         output.extend(quote! {
             impl #linter {
-                pub fn rules(&self) -> ::std::vec::IntoIter<Rule> {
+                pub(crate) fn rules(&self) -> ::std::vec::IntoIter<Rule> {
                     match self { #prefix_into_iter_match_arms }
                 }
             }
@@ -182,7 +182,7 @@ pub(crate) fn map_codes(func: &ItemFn) -> syn::Result<TokenStream> {
     }
     output.extend(quote! {
         impl RuleCodePrefix {
-            pub fn parse(linter: &Linter, code: &str) -> Result<Self, crate::registry::FromCodeError> {
+            pub(crate) fn parse(linter: &Linter, code: &str) -> Result<Self, crate::registry::FromCodeError> {
                 use std::str::FromStr;
 
                 Ok(match linter {
@@ -190,7 +190,7 @@ pub(crate) fn map_codes(func: &ItemFn) -> syn::Result<TokenStream> {
                 })
             }
 
-            pub fn rules(&self) -> ::std::vec::IntoIter<Rule> {
+            pub(crate) fn rules(&self) -> ::std::vec::IntoIter<Rule> {
                 match self {
                     #(RuleCodePrefix::#linter_idents(prefix) => prefix.clone().rules(),)*
                 }
@@ -319,7 +319,7 @@ See also https://github.com/astral-sh/ruff/issues/2186.
                 matches!(self.group(), RuleGroup::Preview)
             }
 
-            pub fn is_stable(&self) -> bool {
+            pub(crate) fn is_stable(&self) -> bool {
                 matches!(self.group(), RuleGroup::Stable)
             }
 
@@ -371,7 +371,7 @@ fn generate_iter_impl(
     quote! {
         impl Linter {
             /// Rules not in the preview.
-            pub fn rules(self: &Linter) -> ::std::vec::IntoIter<Rule> {
+            pub(crate) fn rules(self: &Linter) -> ::std::vec::IntoIter<Rule> {
                 match self {
                     #linter_rules_match_arms
                 }
@@ -385,7 +385,7 @@ fn generate_iter_impl(
         }
 
         impl RuleCodePrefix {
-            pub fn iter() -> impl Iterator<Item = RuleCodePrefix> {
+            pub(crate) fn iter() -> impl Iterator<Item = RuleCodePrefix> {
                 use strum::IntoEnumIterator;
 
                 let mut prefixes = Vec::new();
@@ -436,7 +436,6 @@ fn register_rules<'a>(input: impl Iterator<Item = &'a Rule>) -> TokenStream {
             PartialOrd,
             Ord,
             ::ruff_macros::CacheKey,
-            AsRefStr,
             ::strum_macros::IntoStaticStr,
             ::strum_macros::EnumString,
             ::serde::Serialize,

crates/ruff_python_formatter/resources/test/fixtures/ruff/trailing_comments.py

@@ -2,6 +2,7 @@
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # NoQA: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # type: This shouldn't break
+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # ty: ignore This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # pyright: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # pylint: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa This shouldn't break

crates/ruff_python_formatter/src/lib.rs

@@ -165,7 +165,7 @@ where
 pub fn formatted_file(db: &dyn Db, file: File) -> Result<Option<String>, FormatModuleError> {
     let options = db.format_options(file);
 
-    let parsed = parsed_module(db.upcast(), file);
+    let parsed = parsed_module(db.upcast(), file).load(db.upcast());
 
     if let Some(first) = parsed.errors().first() {
         return Err(FormatModuleError::ParseError(first.clone()));
@@ -174,7 +174,7 @@ pub fn formatted_file(db: &dyn Db, file: File) -> Result<Option<String>, FormatM
     let comment_ranges = CommentRanges::from(parsed.tokens());
     let source = source_text(db.upcast(), file);
 
-    let formatted = format_node(parsed, &comment_ranges, &source, options)?;
+    let formatted = format_node(&parsed, &comment_ranges, &source, options)?;
     let printed = formatted.print()?;
 
     if printed.as_code() == &*source {

crates/ruff_python_formatter/tests/snapshots/format@trailing_comments.py.snap

@@ -1,7 +1,6 @@
 ---
 source: crates/ruff_python_formatter/tests/fixtures.rs
 input_file: crates/ruff_python_formatter/resources/test/fixtures/ruff/trailing_comments.py
-snapshot_kind: text
 ---
 ## Input
 ```python
@@ -9,6 +8,7 @@ snapshot_kind: text
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # NoQA: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # type: This shouldn't break
+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # ty: ignore This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # pyright: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # pylint: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa This shouldn't break
@@ -44,6 +44,7 @@ i = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # NoQA: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # type: This shouldn't break
+i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # ty: ignore This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # pyright: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # pylint: This shouldn't break
 i = ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",)  # noqa This shouldn't break

crates/ruff_python_trivia/src/pragmas.rs

@@ -26,5 +26,5 @@ pub fn is_pragma_comment(comment: &str) -> bool {
         // Case-sensitive match against a variety of pragmas that _do_ require a trailing colon.
         trimmed
         .split_once(':')
-        .is_some_and(|(maybe_pragma, _)| matches!(maybe_pragma, "isort" | "type" | "pyright" | "pylint" | "flake8" | "ruff"))
+        .is_some_and(|(maybe_pragma, _)| matches!(maybe_pragma, "isort" | "type" | "pyright" | "pylint" | "flake8" | "ruff" | "ty"))
 }

crates/ruff_server/src/lint.rs

@@ -242,7 +242,7 @@ fn to_lsp_diagnostic(
     let body = diagnostic.body().to_string();
     let fix = diagnostic.fix();
     let suggestion = diagnostic.suggestion();
-    let code = diagnostic.to_noqa_code();
+    let code = diagnostic.noqa_code();
 
     let fix = fix.and_then(|fix| fix.applies(Applicability::Unsafe).then_some(fix));
 

crates/ruff_server/src/server/api/requests/hover.rs

@@ -85,7 +85,7 @@ pub(crate) fn hover(
 
 fn format_rule_text(rule: Rule) -> String {
     let mut output = String::new();
-    let _ = write!(&mut output, "# {} ({})", rule.as_ref(), rule.noqa_code());
+    let _ = write!(&mut output, "# {} ({})", rule.name(), rule.noqa_code());
     output.push('\n');
     output.push('\n');
 

crates/ruff_wasm/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff_wasm"
-version = "0.11.12"
+version = "0.11.13"
 publish = false
 authors = { workspace = true }
 edition = { workspace = true }

crates/ruff_wasm/src/lib.rs

@@ -208,7 +208,7 @@ impl Workspace {
         let messages: Vec<ExpandedMessage> = messages
             .into_iter()
             .map(|msg| ExpandedMessage {
-                code: msg.to_noqa_code().map(|code| code.to_string()),
+                code: msg.noqa_code().map(|code| code.to_string()),
                 message: msg.body().to_string(),
                 start_location: source_code.line_column(msg.start()).into(),
                 end_location: source_code.line_column(msg.end()).into(),

crates/ruff_wasm/tests/api.rs

@@ -65,7 +65,7 @@ fn syntax_error() {
 fn unsupported_syntax_error() {
     check!(
         "match 2:\n    case 1: ...",
-        r#"{"preview": true, "target-version": "py39"}"#,
+        r#"{"target-version": "py39"}"#,
         [ExpandedMessage {
             code: None,
             message: "SyntaxError: Cannot use `match` statement on Python 3.9 (syntax was added in Python 3.10)".to_string(),

crates/ruff_workspace/src/configuration.rs

@@ -1098,7 +1098,7 @@ impl LintConfiguration {
         // approach to give each pair it's own `warn_user_once`.
         for (preferred, expendable, message) in INCOMPATIBLE_CODES {
             if rules.enabled(*preferred) && rules.enabled(*expendable) {
-                warn_user_once_by_id!(expendable.as_ref(), "{}", message);
+                warn_user_once_by_id!(expendable.name().as_str(), "{}", message);
                 rules.disable(*expendable);
             }
         }

crates/ty/src/lib.rs

@@ -18,10 +18,9 @@ use clap::{CommandFactory, Parser};
 use colored::Colorize;
 use crossbeam::channel as crossbeam_channel;
 use rayon::ThreadPoolBuilder;
-use ruff_db::Upcast;
 use ruff_db::diagnostic::{Diagnostic, DisplayDiagnosticConfig, Severity};
-use ruff_db::max_parallelism;
 use ruff_db::system::{OsSystem, SystemPath, SystemPathBuf};
+use ruff_db::{Upcast, max_parallelism};
 use salsa::plumbing::ZalsaDatabase;
 use ty_project::metadata::options::ProjectOptionsOverrides;
 use ty_project::watch::ProjectWatcher;

crates/ty/tests/cli/config_option.rs

@@ -0,0 +1,206 @@
+use insta_cmd::assert_cmd_snapshot;
+
+use crate::CliTest;
+
+#[test]
+fn cli_config_args_toml_string_basic() -> anyhow::Result<()> {
+    let case = CliTest::with_file("test.py", r"print(x)  # [unresolved-reference]")?;
+
+    // Long flag
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference").arg("--config").arg("terminal.error-on-warning=true"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // Short flag
+    assert_cmd_snapshot!(case.command().arg("-c").arg("terminal.error-on-warning=true"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn cli_config_args_overrides_ty_toml() -> anyhow::Result<()> {
+    let case = CliTest::with_files(vec![
+        (
+            "ty.toml",
+            r#"
+            [terminal]
+            error-on-warning = true
+            "#,
+        ),
+        ("test.py", r"print(x)  # [unresolved-reference]"),
+    ])?;
+
+    // Exit code of 1 due to the setting in `ty.toml`
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // Exit code of 0 because the `ty.toml` setting is overwritten by `--config`
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference").arg("--config").arg("terminal.error-on-warning=false"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn cli_config_args_later_overrides_earlier() -> anyhow::Result<()> {
+    let case = CliTest::with_file("test.py", r"print(x)  # [unresolved-reference]")?;
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference").arg("--config").arg("terminal.error-on-warning=true").arg("--config").arg("terminal.error-on-warning=false"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn cli_config_args_invalid_option() -> anyhow::Result<()> {
+    let case = CliTest::with_file("test.py", r"print(1)")?;
+    assert_cmd_snapshot!(case.command().arg("--config").arg("bad-option=true"), @r###"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    error: TOML parse error at line 1, column 1
+      |
+    1 | bad-option=true
+      | ^^^^^^^^^^
+    unknown field `bad-option`, expected one of `environment`, `src`, `rules`, `terminal`
+
+
+    Usage: ty <COMMAND>
+
+    For more information, try '--help'.
+    "###);
+
+    Ok(())
+}
+
+#[test]
+fn config_file_override() -> anyhow::Result<()> {
+    // Set `error-on-warning` to true in the configuration file
+    // Explicitly set `--warn unresolved-reference` to ensure the rule warns instead of errors
+    let case = CliTest::with_files(vec![
+        ("test.py", r"print(x)  # [unresolved-reference]"),
+        (
+            "ty-override.toml",
+            r#"
+            [terminal]
+            error-on-warning = true
+            "#,
+        ),
+    ])?;
+
+    // Ensure flag works via CLI arg
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference").arg("--config-file").arg("ty-override.toml"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // Ensure the flag works via an environment variable
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference").env("TY_CONFIG_FILE", "ty-override.toml"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}

crates/ty/tests/cli/exit_code.rs

@@ -0,0 +1,272 @@
+use insta_cmd::assert_cmd_snapshot;
+
+use crate::CliTest;
+
+#[test]
+fn only_warnings() -> anyhow::Result<()> {
+    let case = CliTest::with_file("test.py", r"print(x)  # [unresolved-reference]")?;
+
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn only_info() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+        from typing_extensions import reveal_type
+        reveal_type(1)
+        "#,
+    )?;
+
+    assert_cmd_snapshot!(case.command(), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    info[revealed-type]: Revealed type
+     --> test.py:3:13
+      |
+    2 | from typing_extensions import reveal_type
+    3 | reveal_type(1)
+      |             ^ `Literal[1]`
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn only_info_and_error_on_warning_is_true() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+        from typing_extensions import reveal_type
+        reveal_type(1)
+        "#,
+    )?;
+
+    assert_cmd_snapshot!(case.command().arg("--error-on-warning"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    info[revealed-type]: Revealed type
+     --> test.py:3:13
+      |
+    2 | from typing_extensions import reveal_type
+    3 | reveal_type(1)
+      |             ^ `Literal[1]`
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn no_errors_but_error_on_warning_is_true() -> anyhow::Result<()> {
+    let case = CliTest::with_file("test.py", r"print(x)  # [unresolved-reference]")?;
+
+    assert_cmd_snapshot!(case.command().arg("--error-on-warning").arg("--warn").arg("unresolved-reference"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn no_errors_but_error_on_warning_is_enabled_in_configuration() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        ("test.py", r"print(x)  # [unresolved-reference]"),
+        (
+            "ty.toml",
+            r#"
+            [terminal]
+            error-on-warning = true
+        "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:1:7
+      |
+    1 | print(x)  # [unresolved-reference]
+      |       ^
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn both_warnings_and_errors() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+        print(x)     # [unresolved-reference]
+        print(4[1])  # [non-subscriptable]
+        "#,
+    )?;
+
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:2:7
+      |
+    2 | print(x)     # [unresolved-reference]
+      |       ^
+    3 | print(4[1])  # [non-subscriptable]
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    error[non-subscriptable]: Cannot subscript object of type `Literal[4]` with no `__getitem__` method
+     --> test.py:3:7
+      |
+    2 | print(x)     # [unresolved-reference]
+    3 | print(4[1])  # [non-subscriptable]
+      |       ^
+      |
+    info: rule `non-subscriptable` is enabled by default
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn both_warnings_and_errors_and_error_on_warning_is_true() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r###"
+        print(x)     # [unresolved-reference]
+        print(4[1])  # [non-subscriptable]
+        "###,
+    )?;
+
+    assert_cmd_snapshot!(case.command().arg("--warn").arg("unresolved-reference").arg("--error-on-warning"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:2:7
+      |
+    2 | print(x)     # [unresolved-reference]
+      |       ^
+    3 | print(4[1])  # [non-subscriptable]
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    error[non-subscriptable]: Cannot subscript object of type `Literal[4]` with no `__getitem__` method
+     --> test.py:3:7
+      |
+    2 | print(x)     # [unresolved-reference]
+    3 | print(4[1])  # [non-subscriptable]
+      |       ^
+      |
+    info: rule `non-subscriptable` is enabled by default
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn exit_zero_is_true() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+        print(x)     # [unresolved-reference]
+        print(4[1])  # [non-subscriptable]
+        "#,
+    )?;
+
+    assert_cmd_snapshot!(case.command().arg("--exit-zero").arg("--warn").arg("unresolved-reference"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[unresolved-reference]: Name `x` used when not defined
+     --> test.py:2:7
+      |
+    2 | print(x)     # [unresolved-reference]
+      |       ^
+    3 | print(4[1])  # [non-subscriptable]
+      |
+    info: rule `unresolved-reference` was selected on the command line
+
+    error[non-subscriptable]: Cannot subscript object of type `Literal[4]` with no `__getitem__` method
+     --> test.py:3:7
+      |
+    2 | print(x)     # [unresolved-reference]
+    3 | print(4[1])  # [non-subscriptable]
+      |       ^
+      |
+    info: rule `non-subscriptable` is enabled by default
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}

crates/ty/tests/cli/main.rs

@@ -0,0 +1,690 @@
+mod config_option;
+mod exit_code;
+mod python_environment;
+mod rule_selection;
+
+use anyhow::Context as _;
+use insta::internals::SettingsBindDropGuard;
+use insta_cmd::{assert_cmd_snapshot, get_cargo_bin};
+use std::{
+    fmt::Write,
+    path::{Path, PathBuf},
+    process::Command,
+};
+use tempfile::TempDir;
+
+#[test]
+fn test_run_in_sub_directory() -> anyhow::Result<()> {
+    let case = CliTest::with_files([("test.py", "~"), ("subdir/nothing", "")])?;
+    assert_cmd_snapshot!(case.command().current_dir(case.root().join("subdir")).arg(".."), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[invalid-syntax]
+     --> <temp_dir>/test.py:1:2
+      |
+    1 | ~
+      |  ^ Expected an expression
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+    Ok(())
+}
+
+#[test]
+fn test_include_hidden_files_by_default() -> anyhow::Result<()> {
+    let case = CliTest::with_files([(".test.py", "~")])?;
+    assert_cmd_snapshot!(case.command(), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[invalid-syntax]
+     --> .test.py:1:2
+      |
+    1 | ~
+      |  ^ Expected an expression
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+    Ok(())
+}
+
+#[test]
+fn test_respect_ignore_files() -> anyhow::Result<()> {
+    // First test that the default option works correctly (the file is skipped)
+    let case = CliTest::with_files([(".ignore", "test.py"), ("test.py", "~")])?;
+    assert_cmd_snapshot!(case.command(), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    WARN No python files found under the given path(s)
+    ");
+
+    // Test that we can set to false via CLI
+    assert_cmd_snapshot!(case.command().arg("--no-respect-ignore-files"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[invalid-syntax]
+     --> test.py:1:2
+      |
+    1 | ~
+      |  ^ Expected an expression
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // Test that we can set to false via config file
+    case.write_file("ty.toml", "src.respect-ignore-files = false")?;
+    assert_cmd_snapshot!(case.command(), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[invalid-syntax]
+     --> test.py:1:2
+      |
+    1 | ~
+      |  ^ Expected an expression
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // Ensure CLI takes precedence
+    case.write_file("ty.toml", "src.respect-ignore-files = true")?;
+    assert_cmd_snapshot!(case.command().arg("--no-respect-ignore-files"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[invalid-syntax]
+     --> test.py:1:2
+      |
+    1 | ~
+      |  ^ Expected an expression
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+    Ok(())
+}
+
+/// Paths specified on the CLI are relative to the current working directory and not the project root.
+///
+/// We test this by adding an extra search path from the CLI to the libs directory when
+/// running the CLI from the child directory (using relative paths).
+///
+/// Project layout:
+/// ```
+///  - libs
+///    |- utils.py
+///  - child
+///    | - test.py
+/// - pyproject.toml
+/// ```
+///
+/// And the command is run in the `child` directory.
+#[test]
+fn cli_arguments_are_relative_to_the_current_directory() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python-version = "3.11"
+            "#,
+        ),
+        (
+            "libs/utils.py",
+            r#"
+            def add(a: int, b: int) -> int:
+                return a + b
+            "#,
+        ),
+        (
+            "child/test.py",
+            r#"
+            from utils import add
+
+            stat = add(10, 15)
+            "#,
+        ),
+    ])?;
+
+    // Make sure that the CLI fails when the `libs` directory is not in the search path.
+    assert_cmd_snapshot!(case.command().current_dir(case.root().join("child")), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-import]: Cannot resolve imported module `utils`
+     --> test.py:2:6
+      |
+    2 | from utils import add
+      |      ^^^^^
+    3 |
+    4 | stat = add(10, 15)
+      |
+    info: make sure your Python environment is properly configured: https://github.com/astral-sh/ty/blob/main/docs/README.md#python-environment
+    info: rule `unresolved-import` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    assert_cmd_snapshot!(case.command().current_dir(case.root().join("child")).arg("--extra-search-path").arg("../libs"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+/// Paths specified in a configuration file are relative to the project root.
+///
+/// We test this by adding `libs` (as a relative path) to the extra search path in the configuration and run
+/// the CLI from a subdirectory.
+///
+/// Project layout:
+/// ```
+///  - libs
+///    |- utils.py
+///  - child
+///    | - test.py
+/// - pyproject.toml
+/// ```
+#[test]
+fn paths_in_configuration_files_are_relative_to_the_project_root() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python-version = "3.11"
+            extra-paths = ["libs"]
+            "#,
+        ),
+        (
+            "libs/utils.py",
+            r#"
+            def add(a: int, b: int) -> int:
+                return a + b
+            "#,
+        ),
+        (
+            "child/test.py",
+            r#"
+            from utils import add
+
+            stat = add(10, 15)
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command().current_dir(case.root().join("child")), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn user_configuration() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "project/ty.toml",
+            r#"
+            [rules]
+            division-by-zero = "warn"
+            "#,
+        ),
+        (
+            "project/main.py",
+            r#"
+            y = 4 / 0
+
+            for a in range(0, int(y)):
+                x = a
+
+            prin(x)
+            "#,
+        ),
+    ])?;
+
+    let config_directory = case.root().join("home/.config");
+    let config_env_var = if cfg!(windows) {
+        "APPDATA"
+    } else {
+        "XDG_CONFIG_HOME"
+    };
+
+    assert_cmd_snapshot!(
+        case.command().current_dir(case.root().join("project")).env(config_env_var, config_directory.as_os_str()),
+        @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[division-by-zero]: Cannot divide object of type `Literal[4]` by zero
+     --> main.py:2:5
+      |
+    2 | y = 4 / 0
+      |     ^^^^^
+    3 |
+    4 | for a in range(0, int(y)):
+      |
+    info: rule `division-by-zero` was selected in the configuration file
+
+    error[unresolved-reference]: Name `prin` used when not defined
+     --> main.py:7:1
+      |
+    5 |     x = a
+    6 |
+    7 | prin(x)
+      | ^^^^
+      |
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "
+    );
+
+    // The user-level configuration sets the severity for `unresolved-reference` to warn.
+    // Changing the level for `division-by-zero` has no effect, because the project-level configuration
+    // has higher precedence.
+    case.write_file(
+        config_directory.join("ty/ty.toml"),
+        r#"
+        [rules]
+        division-by-zero = "error"
+        unresolved-reference = "warn"
+        "#,
+    )?;
+
+    assert_cmd_snapshot!(
+        case.command().current_dir(case.root().join("project")).env(config_env_var, config_directory.as_os_str()),
+        @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[division-by-zero]: Cannot divide object of type `Literal[4]` by zero
+     --> main.py:2:5
+      |
+    2 | y = 4 / 0
+      |     ^^^^^
+    3 |
+    4 | for a in range(0, int(y)):
+      |
+    info: rule `division-by-zero` was selected in the configuration file
+
+    warning[unresolved-reference]: Name `prin` used when not defined
+     --> main.py:7:1
+      |
+    5 |     x = a
+    6 |
+    7 | prin(x)
+      | ^^^^
+      |
+    info: rule `unresolved-reference` was selected in the configuration file
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "
+    );
+
+    Ok(())
+}
+
+#[test]
+fn check_specific_paths() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "project/main.py",
+            r#"
+            y = 4 / 0  # error: division-by-zero
+            "#,
+        ),
+        (
+            "project/tests/test_main.py",
+            r#"
+            import does_not_exist  # error: unresolved-import
+            "#,
+        ),
+        (
+            "project/other.py",
+            r#"
+            from main2 import z  # error: unresolved-import
+
+            print(z)
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(
+        case.command(),
+        @r###"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-import]: Cannot resolve imported module `main2`
+     --> project/other.py:2:6
+      |
+    2 | from main2 import z  # error: unresolved-import
+      |      ^^^^^
+    3 |
+    4 | print(z)
+      |
+    info: make sure your Python environment is properly configured: https://github.com/astral-sh/ty/blob/main/docs/README.md#python-environment
+    info: rule `unresolved-import` is enabled by default
+
+    error[unresolved-import]: Cannot resolve imported module `does_not_exist`
+     --> project/tests/test_main.py:2:8
+      |
+    2 | import does_not_exist  # error: unresolved-import
+      |        ^^^^^^^^^^^^^^
+      |
+    info: make sure your Python environment is properly configured: https://github.com/astral-sh/ty/blob/main/docs/README.md#python-environment
+    info: rule `unresolved-import` is enabled by default
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "###
+    );
+
+    // Now check only the `tests` and `other.py` files.
+    // We should no longer see any diagnostics related to `main.py`.
+    assert_cmd_snapshot!(
+        case.command().arg("project/tests").arg("project/other.py"),
+        @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-import]: Cannot resolve imported module `main2`
+     --> project/other.py:2:6
+      |
+    2 | from main2 import z  # error: unresolved-import
+      |      ^^^^^
+    3 |
+    4 | print(z)
+      |
+    info: make sure your Python environment is properly configured: https://github.com/astral-sh/ty/blob/main/docs/README.md#python-environment
+    info: rule `unresolved-import` is enabled by default
+
+    error[unresolved-import]: Cannot resolve imported module `does_not_exist`
+     --> project/tests/test_main.py:2:8
+      |
+    2 | import does_not_exist  # error: unresolved-import
+      |        ^^^^^^^^^^^^^^
+      |
+    info: make sure your Python environment is properly configured: https://github.com/astral-sh/ty/blob/main/docs/README.md#python-environment
+    info: rule `unresolved-import` is enabled by default
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "
+    );
+
+    Ok(())
+}
+
+#[test]
+fn check_non_existing_path() -> anyhow::Result<()> {
+    let case = CliTest::with_files([])?;
+
+    let mut settings = insta::Settings::clone_current();
+    settings.add_filter(
+        &regex::escape("The system cannot find the path specified. (os error 3)"),
+        "No such file or directory (os error 2)",
+    );
+    let _s = settings.bind_to_scope();
+
+    assert_cmd_snapshot!(
+        case.command().arg("project/main.py").arg("project/tests"),
+        @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[io]: `<temp_dir>/project/main.py`: No such file or directory (os error 2)
+
+    error[io]: `<temp_dir>/project/tests`: No such file or directory (os error 2)
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    WARN No python files found under the given path(s)
+    "
+    );
+
+    Ok(())
+}
+
+#[test]
+fn concise_diagnostics() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+        print(x)     # [unresolved-reference]
+        print(4[1])  # [non-subscriptable]
+        "#,
+    )?;
+
+    assert_cmd_snapshot!(case.command().arg("--output-format=concise").arg("--warn").arg("unresolved-reference"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    warning[unresolved-reference] test.py:2:7: Name `x` used when not defined
+    error[non-subscriptable] test.py:3:7: Cannot subscript object of type `Literal[4]` with no `__getitem__` method
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+/// This tests the diagnostic format for revealed type.
+///
+/// This test was introduced because changes were made to
+/// how the revealed type diagnostic was constructed and
+/// formatted in "verbose" mode. But it required extra
+/// logic to ensure the concise version didn't regress on
+/// information content. So this test was introduced to
+/// capture that.
+#[test]
+fn concise_revealed_type() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+        from typing_extensions import reveal_type
+
+        x = "hello"
+        reveal_type(x)
+        "#,
+    )?;
+
+    assert_cmd_snapshot!(case.command().arg("--output-format=concise"), @r#"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    info[revealed-type] test.py:5:13: Revealed type: `Literal["hello"]`
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "#);
+
+    Ok(())
+}
+
+#[test]
+fn can_handle_large_binop_expressions() -> anyhow::Result<()> {
+    let mut content = String::new();
+    writeln!(
+        &mut content,
+        "
+        from typing_extensions import reveal_type
+        total = 1{plus_one_repeated}
+        reveal_type(total)
+        ",
+        plus_one_repeated = " + 1".repeat(2000 - 1)
+    )?;
+
+    let case = CliTest::with_file("test.py", &ruff_python_trivia::textwrap::dedent(&content))?;
+
+    assert_cmd_snapshot!(case.command(), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    info[revealed-type]: Revealed type
+     --> test.py:4:13
+      |
+    2 | from typing_extensions import reveal_type
+    3 | total = 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1...
+    4 | reveal_type(total)
+      |             ^^^^^ `Literal[2000]`
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+pub(crate) struct CliTest {
+    _temp_dir: TempDir,
+    _settings_scope: SettingsBindDropGuard,
+    project_dir: PathBuf,
+}
+
+impl CliTest {
+    pub(crate) fn new() -> anyhow::Result<Self> {
+        let temp_dir = TempDir::new()?;
+
+        // Canonicalize the tempdir path because macos uses symlinks for tempdirs
+        // and that doesn't play well with our snapshot filtering.
+        // Simplify with dunce because otherwise we get UNC paths on Windows.
+        let project_dir = dunce::simplified(
+            &temp_dir
+                .path()
+                .canonicalize()
+                .context("Failed to canonicalize project path")?,
+        )
+        .to_path_buf();
+
+        let mut settings = insta::Settings::clone_current();
+        settings.add_filter(&tempdir_filter(&project_dir), "<temp_dir>/");
+        settings.add_filter(r#"\\(\w\w|\s|\.|")"#, "/$1");
+
+        let settings_scope = settings.bind_to_scope();
+
+        Ok(Self {
+            project_dir,
+            _temp_dir: temp_dir,
+            _settings_scope: settings_scope,
+        })
+    }
+
+    pub(crate) fn with_files<'a>(
+        files: impl IntoIterator<Item = (&'a str, &'a str)>,
+    ) -> anyhow::Result<Self> {
+        let case = Self::new()?;
+        case.write_files(files)?;
+        Ok(case)
+    }
+
+    pub(crate) fn with_file(path: impl AsRef<Path>, content: &str) -> anyhow::Result<Self> {
+        let case = Self::new()?;
+        case.write_file(path, content)?;
+        Ok(case)
+    }
+
+    pub(crate) fn write_files<'a>(
+        &self,
+        files: impl IntoIterator<Item = (&'a str, &'a str)>,
+    ) -> anyhow::Result<()> {
+        for (path, content) in files {
+            self.write_file(path, content)?;
+        }
+
+        Ok(())
+    }
+
+    pub(crate) fn write_file(&self, path: impl AsRef<Path>, content: &str) -> anyhow::Result<()> {
+        let path = path.as_ref();
+        let path = self.project_dir.join(path);
+
+        if let Some(parent) = path.parent() {
+            std::fs::create_dir_all(parent)
+                .with_context(|| format!("Failed to create directory `{}`", parent.display()))?;
+        }
+        std::fs::write(&path, &*ruff_python_trivia::textwrap::dedent(content))
+            .with_context(|| format!("Failed to write file `{path}`", path = path.display()))?;
+
+        Ok(())
+    }
+
+    pub(crate) fn root(&self) -> &Path {
+        &self.project_dir
+    }
+
+    pub(crate) fn command(&self) -> Command {
+        let mut command = Command::new(get_cargo_bin("ty"));
+        command.current_dir(&self.project_dir).arg("check");
+
+        // Unset environment variables that can affect test behavior
+        command.env_remove("VIRTUAL_ENV");
+        command.env_remove("CONDA_PREFIX");
+
+        command
+    }
+}
+
+fn tempdir_filter(path: &Path) -> String {
+    format!(r"{}\\?/?", regex::escape(path.to_str().unwrap()))
+}

crates/ty/tests/cli/python_environment.rs

@@ -0,0 +1,774 @@
+use insta_cmd::assert_cmd_snapshot;
+use ruff_python_ast::PythonVersion;
+
+use crate::CliTest;
+
+/// Specifying an option on the CLI should take precedence over the same setting in the
+/// project's configuration. Here, this is tested for the Python version.
+#[test]
+fn config_override_python_version() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python-version = "3.11"
+            "#,
+        ),
+        (
+            "test.py",
+            r#"
+            import sys
+
+            # Access `sys.last_exc` that was only added in Python 3.12
+            print(sys.last_exc)
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-attribute]: Type `<module 'sys'>` has no attribute `last_exc`
+     --> test.py:5:7
+      |
+    4 | # Access `sys.last_exc` that was only added in Python 3.12
+    5 | print(sys.last_exc)
+      |       ^^^^^^^^^^^^
+      |
+    info: rule `unresolved-attribute` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    assert_cmd_snapshot!(case.command().arg("--python-version").arg("3.12"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+/// Same as above, but for the Python platform.
+#[test]
+fn config_override_python_platform() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python-platform = "linux"
+            "#,
+        ),
+        (
+            "test.py",
+            r#"
+            import sys
+            from typing_extensions import reveal_type
+
+            reveal_type(sys.platform)
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r#"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    info[revealed-type]: Revealed type
+     --> test.py:5:13
+      |
+    3 | from typing_extensions import reveal_type
+    4 |
+    5 | reveal_type(sys.platform)
+      |             ^^^^^^^^^^^^ `Literal["linux"]`
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "#);
+
+    assert_cmd_snapshot!(case.command().arg("--python-platform").arg("all"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    info[revealed-type]: Revealed type
+     --> test.py:5:13
+      |
+    3 | from typing_extensions import reveal_type
+    4 |
+    5 | reveal_type(sys.platform)
+      |             ^^^^^^^^^^^^ `LiteralString`
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn config_file_annotation_showing_where_python_version_set_typing_error() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python-version = "3.8"
+            "#,
+        ),
+        (
+            "test.py",
+            r#"
+            aiter
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r#"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-reference]: Name `aiter` used when not defined
+     --> test.py:2:1
+      |
+    2 | aiter
+      | ^^^^^
+      |
+    info: `aiter` was added as a builtin in Python 3.10
+    info: Python 3.8 was assumed when resolving types
+     --> pyproject.toml:3:18
+      |
+    2 | [tool.ty.environment]
+    3 | python-version = "3.8"
+      |                  ^^^^^ Python 3.8 assumed due to this configuration setting
+      |
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "#);
+
+    assert_cmd_snapshot!(case.command().arg("--python-version=3.9"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-reference]: Name `aiter` used when not defined
+     --> test.py:2:1
+      |
+    2 | aiter
+      | ^^^^^
+      |
+    info: `aiter` was added as a builtin in Python 3.10
+    info: Python 3.9 was assumed when resolving types because it was specified on the command line
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn pyvenv_cfg_file_annotation_showing_where_python_version_set() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python = "venv"
+            "#,
+        ),
+        (
+            "venv/pyvenv.cfg",
+            r#"
+            version = 3.8
+            home = foo/bar/bin
+            "#,
+        ),
+        if cfg!(target_os = "windows") {
+            ("foo/bar/bin/python.exe", "")
+        } else {
+            ("foo/bar/bin/python", "")
+        },
+        if cfg!(target_os = "windows") {
+            ("venv/Lib/site-packages/foo.py", "")
+        } else {
+            ("venv/lib/python3.8/site-packages/foo.py", "")
+        },
+        ("test.py", "aiter"),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-reference]: Name `aiter` used when not defined
+     --> test.py:1:1
+      |
+    1 | aiter
+      | ^^^^^
+      |
+    info: `aiter` was added as a builtin in Python 3.10
+    info: Python 3.8 was assumed when resolving types because of your virtual environment
+     --> venv/pyvenv.cfg:2:11
+      |
+    2 | version = 3.8
+      |           ^^^ Python version inferred from virtual environment metadata file
+    3 | home = foo/bar/bin
+      |
+    info: No Python version was specified on the command line or in a configuration file
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn pyvenv_cfg_file_annotation_no_trailing_newline() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python = "venv"
+            "#,
+        ),
+        (
+            "venv/pyvenv.cfg",
+            r#"home = foo/bar/bin
+
+
+            version = 3.8"#,
+        ),
+        if cfg!(target_os = "windows") {
+            ("foo/bar/bin/python.exe", "")
+        } else {
+            ("foo/bar/bin/python", "")
+        },
+        if cfg!(target_os = "windows") {
+            ("venv/Lib/site-packages/foo.py", "")
+        } else {
+            ("venv/lib/python3.8/site-packages/foo.py", "")
+        },
+        ("test.py", "aiter"),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-reference]: Name `aiter` used when not defined
+     --> test.py:1:1
+      |
+    1 | aiter
+      | ^^^^^
+      |
+    info: `aiter` was added as a builtin in Python 3.10
+    info: Python 3.8 was assumed when resolving types because of your virtual environment
+     --> venv/pyvenv.cfg:4:23
+      |
+    4 |             version = 3.8
+      |                       ^^^ Python version inferred from virtual environment metadata file
+      |
+    info: No Python version was specified on the command line or in a configuration file
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn config_file_annotation_showing_where_python_version_set_syntax_error() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [project]
+            requires-python = ">=3.8"
+            "#,
+        ),
+        (
+            "test.py",
+            r#"
+            match object():
+                case int():
+                    pass
+                case _:
+                    pass
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r#"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[invalid-syntax]
+     --> test.py:2:1
+      |
+    2 | match object():
+      | ^^^^^ Cannot use `match` statement on Python 3.8 (syntax was added in Python 3.10)
+    3 |     case int():
+    4 |         pass
+      |
+    info: Python 3.8 was assumed when parsing syntax
+     --> pyproject.toml:3:19
+      |
+    2 | [project]
+    3 | requires-python = ">=3.8"
+      |                   ^^^^^^^ Python 3.8 assumed due to this configuration setting
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "#);
+
+    assert_cmd_snapshot!(case.command().arg("--python-version=3.9"), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[invalid-syntax]
+     --> test.py:2:1
+      |
+    2 | match object():
+      | ^^^^^ Cannot use `match` statement on Python 3.9 (syntax was added in Python 3.10)
+    3 |     case int():
+    4 |         pass
+      |
+    info: Python 3.9 was assumed when parsing syntax because it was specified on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn python_cli_argument_virtual_environment() -> anyhow::Result<()> {
+    let path_to_executable = if cfg!(windows) {
+        "my-venv/Scripts/python.exe"
+    } else {
+        "my-venv/bin/python"
+    };
+
+    let other_venv_path = "my-venv/foo/some_other_file.txt";
+
+    let case = CliTest::with_files([
+        ("test.py", ""),
+        (
+            if cfg!(windows) {
+                "my-venv/Lib/site-packages/foo.py"
+            } else {
+                "my-venv/lib/python3.13/site-packages/foo.py"
+            },
+            "",
+        ),
+        (path_to_executable, ""),
+        (other_venv_path, ""),
+    ])?;
+
+    // Passing a path to the installation works
+    assert_cmd_snapshot!(case.command().arg("--python").arg("my-venv"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // And so does passing a path to the executable inside the installation
+    assert_cmd_snapshot!(case.command().arg("--python").arg(path_to_executable), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // But random other paths inside the installation are rejected
+    assert_cmd_snapshot!(case.command().arg("--python").arg(other_venv_path), @r"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ty failed
+      Cause: Invalid search path settings
+      Cause: Failed to discover the site-packages directory: Invalid `--python` argument `<temp_dir>/my-venv/foo/some_other_file.txt`: does not point to a Python executable or a directory on disk
+    ");
+
+    // And so are paths that do not exist on disk
+    assert_cmd_snapshot!(case.command().arg("--python").arg("not-a-directory-or-executable"), @r"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ty failed
+      Cause: Invalid search path settings
+      Cause: Failed to discover the site-packages directory: Invalid `--python` argument `<temp_dir>/not-a-directory-or-executable`: does not point to a Python executable or a directory on disk
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn python_cli_argument_system_installation() -> anyhow::Result<()> {
+    let path_to_executable = if cfg!(windows) {
+        "Python3.11/python.exe"
+    } else {
+        "Python3.11/bin/python"
+    };
+
+    let case = CliTest::with_files([
+        ("test.py", ""),
+        (
+            if cfg!(windows) {
+                "Python3.11/Lib/site-packages/foo.py"
+            } else {
+                "Python3.11/lib/python3.11/site-packages/foo.py"
+            },
+            "",
+        ),
+        (path_to_executable, ""),
+    ])?;
+
+    // Passing a path to the installation works
+    assert_cmd_snapshot!(case.command().arg("--python").arg("Python3.11"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // And so does passing a path to the executable inside the installation
+    assert_cmd_snapshot!(case.command().arg("--python").arg(path_to_executable), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+#[test]
+fn config_file_broken_python_setting() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [project]
+            name = "test"
+            version = "0.1.0"
+            description = "Some description"
+            readme = "README.md"
+            requires-python = ">=3.13"
+            dependencies = []
+
+            [tool.ty.environment]
+            python = "not-a-directory-or-executable"
+            "#,
+        ),
+        ("test.py", ""),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r#"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ty failed
+      Cause: Invalid search path settings
+      Cause: Failed to discover the site-packages directory: Invalid `environment.python` setting
+
+    --> Invalid setting in configuration file `<temp_dir>/pyproject.toml`
+       |
+     9 |
+    10 | [tool.ty.environment]
+    11 | python = "not-a-directory-or-executable"
+       |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ does not point to a Python executable or a directory on disk
+       |
+    "#);
+
+    Ok(())
+}
+
+#[test]
+fn config_file_python_setting_directory_with_no_site_packages() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python = "directory-but-no-site-packages"
+            "#,
+        ),
+        ("directory-but-no-site-packages/lib/foo.py", ""),
+        ("test.py", ""),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r#"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ty failed
+      Cause: Invalid search path settings
+      Cause: Failed to discover the site-packages directory: Invalid `environment.python` setting
+
+    --> Invalid setting in configuration file `<temp_dir>/pyproject.toml`
+      |
+    1 |
+    2 | [tool.ty.environment]
+    3 | python = "directory-but-no-site-packages"
+      |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Could not find a `site-packages` directory for this Python installation/executable
+      |
+    "#);
+
+    Ok(())
+}
+
+// This error message is never emitted on Windows, because Windows installations have simpler layouts
+#[cfg(not(windows))]
+#[test]
+fn unix_system_installation_with_no_lib_directory() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.environment]
+            python = "directory-but-no-site-packages"
+            "#,
+        ),
+        ("directory-but-no-site-packages/foo.py", ""),
+        ("test.py", ""),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r#"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ty failed
+      Cause: Invalid search path settings
+      Cause: Failed to discover the site-packages directory: Failed to iterate over the contents of the `lib` directory of the Python installation
+
+    --> Invalid setting in configuration file `<temp_dir>/pyproject.toml`
+      |
+    1 |
+    2 | [tool.ty.environment]
+    3 | python = "directory-but-no-site-packages"
+      |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+      |
+    "#);
+
+    Ok(())
+}
+
+#[test]
+fn defaults_to_a_new_python_version() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "ty.toml",
+            &*format!(
+                r#"
+                [environment]
+                python-version = "{}"
+                python-platform = "linux"
+                "#,
+                PythonVersion::default()
+            ),
+        ),
+        (
+            "main.py",
+            r#"
+            import os
+
+            os.grantpt(1) # only available on unix, Python 3.13 or newer
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-attribute]: Type `<module 'os'>` has no attribute `grantpt`
+     --> main.py:4:1
+      |
+    2 | import os
+    3 |
+    4 | os.grantpt(1) # only available on unix, Python 3.13 or newer
+      | ^^^^^^^^^^
+      |
+    info: rule `unresolved-attribute` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // Use default (which should be latest supported)
+    let case = CliTest::with_files([
+        (
+            "ty.toml",
+            r#"
+            [environment]
+            python-platform = "linux"
+            "#,
+        ),
+        (
+            "main.py",
+            r#"
+            import os
+
+            os.grantpt(1) # only available on unix, Python 3.13 or newer
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+/// The `site-packages` directory is used by ty for external import.
+/// Ty does the following checks to discover the `site-packages` directory in the order:
+/// 1) If `VIRTUAL_ENV` environment variable is set
+/// 2) If `CONDA_PREFIX` environment variable is set
+/// 3) If a `.venv` directory exists at the project root
+///
+/// This test is aiming at validating the logic around `CONDA_PREFIX`.
+///
+/// A conda-like environment file structure is used
+/// We test by first not setting the `CONDA_PREFIX` and expect a fail.
+/// Then we test by setting `CONDA_PREFIX` to `conda-env` and expect a pass.
+///
+/// ├── project
+/// │   └── test.py
+/// └── conda-env
+///     └── lib
+///         └── python3.13
+///             └── site-packages
+///                 └── package1
+///                     └── __init__.py
+///
+/// test.py imports package1
+/// And the command is run in the `child` directory.
+#[test]
+fn check_conda_prefix_var_to_resolve_path() -> anyhow::Result<()> {
+    let conda_package1_path = if cfg!(windows) {
+        "conda-env/Lib/site-packages/package1/__init__.py"
+    } else {
+        "conda-env/lib/python3.13/site-packages/package1/__init__.py"
+    };
+
+    let case = CliTest::with_files([
+        (
+            "project/test.py",
+            r#"
+            import package1
+            "#,
+        ),
+        (
+            conda_package1_path,
+            r#"
+            "#,
+        ),
+    ])?;
+
+    assert_cmd_snapshot!(case.command().current_dir(case.root().join("project")), @r"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-import]: Cannot resolve imported module `package1`
+     --> test.py:2:8
+      |
+    2 | import package1
+      |        ^^^^^^^^
+      |
+    info: make sure your Python environment is properly configured: https://github.com/astral-sh/ty/blob/main/docs/README.md#python-environment
+    info: rule `unresolved-import` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    // do command : CONDA_PREFIX=<temp_dir>/conda_env
+    assert_cmd_snapshot!(case.command().current_dir(case.root().join("project")).env("CONDA_PREFIX", case.root().join("conda-env")), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    All checks passed!
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}

crates/ty/tests/cli/rule_selection.rs

@@ -0,0 +1,292 @@
+use insta_cmd::assert_cmd_snapshot;
+
+use crate::CliTest;
+
+/// The rule severity can be changed in the configuration file
+#[test]
+fn configuration_rule_severity() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+            y = 4 / 0
+
+            for a in range(0, int(y)):
+                x = a
+
+            prin(x)  # unresolved-reference
+            "#,
+    )?;
+
+    // Assert that there's an `unresolved-reference` diagnostic (error).
+    assert_cmd_snapshot!(case.command(), @r###"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-reference]: Name `prin` used when not defined
+     --> test.py:7:1
+      |
+    5 |     x = a
+    6 |
+    7 | prin(x)  # unresolved-reference
+      | ^^^^
+      |
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "###);
+
+    case.write_file(
+        "pyproject.toml",
+        r#"
+        [tool.ty.rules]
+        division-by-zero = "warn" # promote to warn
+        unresolved-reference = "ignore"
+    "#,
+    )?;
+
+    assert_cmd_snapshot!(case.command(), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[division-by-zero]: Cannot divide object of type `Literal[4]` by zero
+     --> test.py:2:5
+      |
+    2 | y = 4 / 0
+      |     ^^^^^
+    3 |
+    4 | for a in range(0, int(y)):
+      |
+    info: rule `division-by-zero` was selected in the configuration file
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}
+
+/// The rule severity can be changed using `--ignore`, `--warn`, and `--error`
+#[test]
+fn cli_rule_severity() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+        import does_not_exit
+
+        y = 4 / 0
+
+        for a in range(0, int(y)):
+            x = a
+
+        prin(x)  # unresolved-reference
+        "#,
+    )?;
+
+    // Assert that there's an `unresolved-reference` diagnostic (error)
+    // and an unresolved-import (error) diagnostic by default.
+    assert_cmd_snapshot!(case.command(), @r###"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-import]: Cannot resolve imported module `does_not_exit`
+     --> test.py:2:8
+      |
+    2 | import does_not_exit
+      |        ^^^^^^^^^^^^^
+    3 |
+    4 | y = 4 / 0
+      |
+    info: make sure your Python environment is properly configured: https://github.com/astral-sh/ty/blob/main/docs/README.md#python-environment
+    info: rule `unresolved-import` is enabled by default
+
+    error[unresolved-reference]: Name `prin` used when not defined
+     --> test.py:9:1
+      |
+    7 |     x = a
+    8 |
+    9 | prin(x)  # unresolved-reference
+      | ^^^^
+      |
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "###);
+
+    assert_cmd_snapshot!(
+        case
+            .command()
+            .arg("--ignore")
+            .arg("unresolved-reference")
+            .arg("--warn")
+            .arg("division-by-zero")
+            .arg("--warn")
+            .arg("unresolved-import"),
+        @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[unresolved-import]: Cannot resolve imported module `does_not_exit`
+     --> test.py:2:8
+      |
+    2 | import does_not_exit
+      |        ^^^^^^^^^^^^^
+    3 |
+    4 | y = 4 / 0
+      |
+    info: make sure your Python environment is properly configured: https://github.com/astral-sh/ty/blob/main/docs/README.md#python-environment
+    info: rule `unresolved-import` was selected on the command line
+
+    warning[division-by-zero]: Cannot divide object of type `Literal[4]` by zero
+     --> test.py:4:5
+      |
+    2 | import does_not_exit
+    3 |
+    4 | y = 4 / 0
+      |     ^^^^^
+    5 |
+    6 | for a in range(0, int(y)):
+      |
+    info: rule `division-by-zero` was selected on the command line
+
+    Found 2 diagnostics
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "
+    );
+
+    Ok(())
+}
+
+/// The rule severity can be changed using `--ignore`, `--warn`, and `--error` and
+/// values specified last override previous severities.
+#[test]
+fn cli_rule_severity_precedence() -> anyhow::Result<()> {
+    let case = CliTest::with_file(
+        "test.py",
+        r#"
+        y = 4 / 0
+
+        for a in range(0, int(y)):
+            x = a
+
+        prin(x)  # unresolved-reference
+        "#,
+    )?;
+
+    // Assert that there's a `unresolved-reference` diagnostic (error) by default.
+    assert_cmd_snapshot!(case.command(), @r###"
+    success: false
+    exit_code: 1
+    ----- stdout -----
+    error[unresolved-reference]: Name `prin` used when not defined
+     --> test.py:7:1
+      |
+    5 |     x = a
+    6 |
+    7 | prin(x)  # unresolved-reference
+      | ^^^^
+      |
+    info: rule `unresolved-reference` is enabled by default
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "###);
+
+    assert_cmd_snapshot!(
+        case
+            .command()
+            .arg("--warn")
+            .arg("unresolved-reference")
+            .arg("--warn")
+            .arg("division-by-zero")
+            .arg("--ignore")
+            .arg("unresolved-reference"),
+        @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[division-by-zero]: Cannot divide object of type `Literal[4]` by zero
+     --> test.py:2:5
+      |
+    2 | y = 4 / 0
+      |     ^^^^^
+    3 |
+    4 | for a in range(0, int(y)):
+      |
+    info: rule `division-by-zero` was selected on the command line
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "
+    );
+
+    Ok(())
+}
+
+/// ty warns about unknown rules specified in a configuration file
+#[test]
+fn configuration_unknown_rules() -> anyhow::Result<()> {
+    let case = CliTest::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.ty.rules]
+            division-by-zer = "warn" # incorrect rule name
+            "#,
+        ),
+        ("test.py", "print(10)"),
+    ])?;
+
+    assert_cmd_snapshot!(case.command(), @r#"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[unknown-rule]
+     --> pyproject.toml:3:1
+      |
+    2 | [tool.ty.rules]
+    3 | division-by-zer = "warn" # incorrect rule name
+      | ^^^^^^^^^^^^^^^ Unknown lint rule `division-by-zer`
+      |
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    "#);
+
+    Ok(())
+}
+
+/// ty warns about unknown rules specified in a CLI argument
+#[test]
+fn cli_unknown_rules() -> anyhow::Result<()> {
+    let case = CliTest::with_file("test.py", "print(10)")?;
+
+    assert_cmd_snapshot!(case.command().arg("--ignore").arg("division-by-zer"), @r"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    warning[unknown-rule]: Unknown lint rule `division-by-zer`
+
+    Found 1 diagnostic
+
+    ----- stderr -----
+    WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
+    ");
+
+    Ok(())
+}

crates/ty_ide/src/completion.rs

@@ -1,7 +1,7 @@
 use std::cmp::Ordering;
 
 use ruff_db::files::File;
-use ruff_db::parsed::{ParsedModule, parsed_module};
+use ruff_db::parsed::{ParsedModuleRef, parsed_module};
 use ruff_python_ast as ast;
 use ruff_python_parser::{Token, TokenAt, TokenKind};
 use ruff_text_size::{Ranged, TextRange, TextSize};
@@ -15,9 +15,9 @@ pub struct Completion {
 }
 
 pub fn completion(db: &dyn Db, file: File, offset: TextSize) -> Vec<Completion> {
-    let parsed = parsed_module(db.upcast(), file);
+    let parsed = parsed_module(db.upcast(), file).load(db.upcast());
 
-    let Some(target) = CompletionTargetTokens::find(parsed, offset).ast(parsed) else {
+    let Some(target) = CompletionTargetTokens::find(&parsed, offset).ast(&parsed) else {
         return vec![];
     };
 
@@ -63,7 +63,7 @@ enum CompletionTargetTokens<'t> {
 
 impl<'t> CompletionTargetTokens<'t> {
     /// Look for the best matching token pattern at the given offset.
-    fn find(parsed: &ParsedModule, offset: TextSize) -> CompletionTargetTokens<'_> {
+    fn find(parsed: &ParsedModuleRef, offset: TextSize) -> CompletionTargetTokens<'_> {
         static OBJECT_DOT_EMPTY: [TokenKind; 2] = [TokenKind::Name, TokenKind::Dot];
         static OBJECT_DOT_NON_EMPTY: [TokenKind; 3] =
             [TokenKind::Name, TokenKind::Dot, TokenKind::Name];
@@ -97,7 +97,7 @@ impl<'t> CompletionTargetTokens<'t> {
     /// Returns a corresponding AST node for these tokens.
     ///
     /// If no plausible AST node could be found, then `None` is returned.
-    fn ast(&self, parsed: &'t ParsedModule) -> Option<CompletionTargetAst<'t>> {
+    fn ast(&self, parsed: &'t ParsedModuleRef) -> Option<CompletionTargetAst<'t>> {
         match *self {
             CompletionTargetTokens::ObjectDot { object, .. } => {
                 let covering_node = covering_node(parsed.syntax().into(), object.range())

crates/ty_ide/src/goto.rs

@@ -1,7 +1,7 @@
 use crate::find_node::covering_node;
 use crate::{Db, HasNavigationTargets, NavigationTargets, RangedValue};
 use ruff_db::files::{File, FileRange};
-use ruff_db::parsed::{ParsedModule, parsed_module};
+use ruff_db::parsed::{ParsedModuleRef, parsed_module};
 use ruff_python_ast::{self as ast, AnyNodeRef};
 use ruff_python_parser::TokenKind;
 use ruff_text_size::{Ranged, TextRange, TextSize};
@@ -13,8 +13,8 @@ pub fn goto_type_definition(
     file: File,
     offset: TextSize,
 ) -> Option<RangedValue<NavigationTargets>> {
-    let parsed = parsed_module(db.upcast(), file);
-    let goto_target = find_goto_target(parsed, offset)?;
+    let module = parsed_module(db.upcast(), file).load(db.upcast());
+    let goto_target = find_goto_target(&module, offset)?;
 
     let model = SemanticModel::new(db.upcast(), file);
     let ty = goto_target.inferred_type(&model)?;
@@ -128,8 +128,8 @@ pub(crate) enum GotoTarget<'a> {
     },
 }
 
-impl<'db> GotoTarget<'db> {
-    pub(crate) fn inferred_type(self, model: &SemanticModel<'db>) -> Option<Type<'db>> {
+impl GotoTarget<'_> {
+    pub(crate) fn inferred_type<'db>(self, model: &SemanticModel<'db>) -> Option<Type<'db>> {
         let ty = match self {
             GotoTarget::Expression(expression) => expression.inferred_type(model),
             GotoTarget::FunctionDef(function) => function.inferred_type(model),
@@ -183,7 +183,10 @@ impl Ranged for GotoTarget<'_> {
     }
 }
 
-pub(crate) fn find_goto_target(parsed: &ParsedModule, offset: TextSize) -> Option<GotoTarget> {
+pub(crate) fn find_goto_target(
+    parsed: &ParsedModuleRef,
+    offset: TextSize,
+) -> Option<GotoTarget<'_>> {
     let token = parsed
         .tokens()
         .at_offset(offset)

crates/ty_ide/src/hover.rs

@@ -8,9 +8,9 @@ use std::fmt::Formatter;
 use ty_python_semantic::SemanticModel;
 use ty_python_semantic::types::Type;
 
-pub fn hover(db: &dyn Db, file: File, offset: TextSize) -> Option<RangedValue<Hover>> {
-    let parsed = parsed_module(db.upcast(), file);
-    let goto_target = find_goto_target(parsed, offset)?;
+pub fn hover(db: &dyn Db, file: File, offset: TextSize) -> Option<RangedValue<Hover<'_>>> {
+    let parsed = parsed_module(db.upcast(), file).load(db.upcast());
+    let goto_target = find_goto_target(&parsed, offset)?;
 
     if let GotoTarget::Expression(expr) = goto_target {
         if expr.is_literal_expr() {

crates/ty_ide/src/inlay_hints.rs

@@ -54,7 +54,7 @@ impl fmt::Display for DisplayInlayHint<'_, '_> {
 pub fn inlay_hints(db: &dyn Db, file: File, range: TextRange) -> Vec<InlayHint<'_>> {
     let mut visitor = InlayHintVisitor::new(db, file, range);
 
-    let ast = parsed_module(db.upcast(), file);
+    let ast = parsed_module(db.upcast(), file).load(db.upcast());
 
     visitor.visit_body(ast.suite());