Improve docs on how to stop Ruff and ty disagreeing with each other

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

@@ -25,6 +25,11 @@ use crate::rules::flake8_boolean_trap::helpers::is_allowed_func_def;
 /// keyword-only argument, to force callers to be explicit when providing
 /// the argument.
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override],
+/// since changing the signature of a subclass method that overrides a
+/// superclass method may cause type checkers to complain about a violation of
+/// the Liskov Substitution Principle.
+///
 /// ## Example
 /// ```python
 /// from math import ceil, floor
@@ -89,6 +94,8 @@ 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/)
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.127")]
 pub(crate) struct BooleanDefaultValuePositionalArgument;

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

@@ -28,7 +28,7 @@ use crate::rules::flake8_boolean_trap::helpers::is_allowed_func_def;
 /// the argument.
 ///
 /// Dunder methods that define operators are exempt from this rule, as are
-/// setters and `@override` definitions.
+/// setters and [`@override`][override] definitions.
 ///
 /// ## Example
 ///
@@ -93,6 +93,8 @@ 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/)
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.127")]
 pub(crate) struct BooleanTypeHintPositionalArgument;

crates/ruff_linter/src/rules/flake8_builtins/rules/builtin_argument_shadowing.rs

@@ -17,6 +17,8 @@ use crate::rules::flake8_builtins::helpers::shadows_builtin;
 /// non-obvious errors, as readers may mistake the argument for the
 /// builtin and vice versa.
 ///
+/// Function definitions decorated with [`@override`][override] or
+/// [`@overload`][overload] are exempt from this rule by default.
 /// Builtins can be marked as exceptions to this rule via the
 /// [`lint.flake8-builtins.ignorelist`] configuration option.
 ///
@@ -48,6 +50,9 @@ use crate::rules::flake8_builtins::helpers::shadows_builtin;
 /// ## References
 /// - [_Is it bad practice to use a built-in function name as an attribute or method identifier?_](https://stackoverflow.com/questions/9109333/is-it-bad-practice-to-use-a-built-in-function-name-as-an-attribute-or-method-ide)
 /// - [_Why is it a bad idea to name a variable `id` in Python?_](https://stackoverflow.com/questions/77552/id-is-a-bad-variable-name-in-python)
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
+/// [overload]: https://docs.python.org/3/library/typing.html#typing.overload
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.48")]
 pub(crate) struct BuiltinArgumentShadowing {

crates/ruff_linter/src/rules/flake8_unused_arguments/rules/unused_arguments.rs

@@ -60,6 +60,16 @@ impl Violation for UnusedFunctionArgument {
 /// prefixed with an underscore, or some other value that adheres to the
 /// [`lint.dummy-variable-rgx`] pattern.
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override].
+/// Removing a parameter from a subclass method (or changing a parameter's
+/// name) may cause type checkers to complain about a violation of the Liskov
+/// Substitution Principle if it means that the method now incompatibly
+/// overrides a method defined on a superclass. Explicitly decorating an
+/// overriding method with `@override` signals to Ruff that the method is
+/// intended to override a superclass method and that a type checker will
+/// enforce that it does so; Ruff therefore knows that it should not enforce
+/// rules about unused arguments on such methods.
+///
 /// ## Example
 /// ```python
 /// class Class:
@@ -76,6 +86,8 @@ impl Violation for UnusedFunctionArgument {
 ///
 /// ## Options
 /// - `lint.dummy-variable-rgx`
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.168")]
 pub(crate) struct UnusedMethodArgument {
@@ -101,6 +113,16 @@ impl Violation for UnusedMethodArgument {
 /// prefixed with an underscore, or some other value that adheres to the
 /// [`lint.dummy-variable-rgx`] pattern.
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override].
+/// Removing a parameter from a subclass method (or changing a parameter's
+/// name) may cause type checkers to complain about a violation of the Liskov
+/// Substitution Principle if it means that the method now incompatibly
+/// overrides a method defined on a superclass. Explicitly decorating an
+/// overriding method with `@override` signals to Ruff that the method is
+/// intended to override a superclass method and that a type checker will
+/// enforce that it does so; Ruff therefore knows that it should not enforce
+/// rules about unused arguments on such methods.
+///
 /// ## Example
 /// ```python
 /// class Class:
@@ -119,6 +141,8 @@ impl Violation for UnusedMethodArgument {
 ///
 /// ## Options
 /// - `lint.dummy-variable-rgx`
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.168")]
 pub(crate) struct UnusedClassMethodArgument {
@@ -144,6 +168,16 @@ impl Violation for UnusedClassMethodArgument {
 /// prefixed with an underscore, or some other value that adheres to the
 /// [`lint.dummy-variable-rgx`] pattern.
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override].
+/// Removing a parameter from a subclass method (or changing a parameter's
+/// name) may cause type checkers to complain about a violation of the Liskov
+/// Substitution Principle if it means that the method now incompatibly
+/// overrides a method defined on a superclass. Explicitly decorating an
+/// overriding method with `@override` signals to Ruff that the method is
+/// intended to override a superclass method, and that a type checker will
+/// enforce that it does so; Ruff therefore knows that it should not enforce
+/// rules about unused arguments on such methods.
+///
 /// ## Example
 /// ```python
 /// class Class:
@@ -162,6 +196,8 @@ impl Violation for UnusedClassMethodArgument {
 ///
 /// ## Options
 /// - `lint.dummy-variable-rgx`
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.168")]
 pub(crate) struct UnusedStaticMethodArgument {

crates/ruff_linter/src/rules/pep8_naming/rules/invalid_argument_name.rs

@@ -23,7 +23,7 @@ use crate::checkers::ast::Checker;
 /// > mixedCase is allowed only in contexts where that’s already the
 /// > prevailing style (e.g. threading.py), to retain backwards compatibility.
 ///
-/// Methods decorated with `@typing.override` are ignored.
+/// Methods decorated with [`@typing.override`][override] are ignored.
 ///
 /// ## Example
 /// ```python
@@ -43,6 +43,8 @@ use crate::checkers::ast::Checker;
 ///
 /// [PEP 8]: https://peps.python.org/pep-0008/#function-and-method-arguments
 /// [preview]: https://docs.astral.sh/ruff/preview/
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.77")]
 pub(crate) struct InvalidArgumentName {

crates/ruff_linter/src/rules/pep8_naming/rules/invalid_function_name.rs

@@ -24,6 +24,11 @@ use crate::rules::pep8_naming::settings::IgnoreNames;
 /// to ignore all functions starting with `test_` from this rule, set the
 /// [`lint.pep8-naming.extend-ignore-names`] option to `["test_*"]`.
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override].
+/// Explicitly decorating a method with `@override` signals to Ruff that the method is intended
+/// to override a superclass method, and that a type checker will enforce that it does so. Ruff
+/// therefore knows that it should not enforce naming conventions on such methods.
+///
 /// ## Example
 /// ```python
 /// def myFunction():
@@ -41,6 +46,7 @@ use crate::rules::pep8_naming::settings::IgnoreNames;
 /// - `lint.pep8-naming.extend-ignore-names`
 ///
 /// [PEP 8]: https://peps.python.org/pep-0008/#function-and-variable-names
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.77")]
 pub(crate) struct InvalidFunctionName {

crates/ruff_linter/src/rules/pydocstyle/rules/not_missing.rs

@@ -169,7 +169,12 @@ impl Violation for UndocumentedPublicClass {
 /// If the codebase adheres to a standard format for method docstrings, follow
 /// that format for consistency.
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override],
+/// since it is a common practice to document a method on a superclass but not
+/// on an overriding method in a subclass.
+///
 /// ## Example
+///
 /// ```python
 /// class Cat(Animal):
 ///     def greet(self, happy: bool = True):
@@ -180,6 +185,7 @@ impl Violation for UndocumentedPublicClass {
 /// ```
 ///
 /// Use instead (in the NumPy docstring format):
+///
 /// ```python
 /// class Cat(Animal):
 ///     def greet(self, happy: bool = True):
@@ -202,6 +208,7 @@ impl Violation for UndocumentedPublicClass {
 /// ```
 ///
 /// Or (in the Google docstring format):
+///
 /// ```python
 /// class Cat(Animal):
 ///     def greet(self, happy: bool = True):
@@ -227,6 +234,8 @@ impl Violation for UndocumentedPublicClass {
 /// - [PEP 287 – reStructuredText Docstring Format](https://peps.python.org/pep-0287/)
 /// - [NumPy Style Guide](https://numpydoc.readthedocs.io/en/latest/format.html)
 /// - [Google Python Style Guide - Docstrings](https://google.github.io/styleguide/pyguide.html#38-comments-and-docstrings)
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.70")]
 pub(crate) struct UndocumentedPublicMethod;

crates/ruff_linter/src/rules/pylint/rules/bad_dunder_method_name.rs

@@ -21,7 +21,7 @@ use crate::rules::pylint::helpers::is_known_dunder_method;
 ///
 /// This rule will detect all methods starting and ending with at least
 /// one underscore (e.g., `_str_`), but ignores known dunder methods (like
-/// `__init__`), as well as methods that are marked with `@override`.
+/// `__init__`), as well as methods that are marked with [`@override`][override].
 ///
 /// Additional dunder methods names can be allowed via the
 /// [`lint.pylint.allow-dunder-method-names`] setting.
@@ -42,6 +42,8 @@ use crate::rules::pylint::helpers::is_known_dunder_method;
 ///
 /// ## Options
 /// - `lint.pylint.allow-dunder-method-names`
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(preview_since = "v0.0.285")]
 pub(crate) struct BadDunderMethodName {

crates/ruff_linter/src/rules/pylint/rules/no_self_use.rs

@@ -17,6 +17,16 @@ use crate::rules::flake8_unused_arguments::rules::is_not_implemented_stub_with_v
 /// Unused `self` parameters are usually a sign of a method that could be
 /// replaced by a function, class method, or static method.
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override].
+/// Converting an instance method into a static method or class method may
+/// cause type checkers to complain about a violation of the Liskov
+/// Substitution Principle if it means that the method now incompatibly
+/// overrides a method defined on a superclass. Explicitly decorating an
+/// overriding method with `@override` signals to Ruff that the method is
+/// intended to override a superclass method and that a type checker will
+/// enforce that it does so; Ruff therefore knows that it should not enforce
+/// rules about unused `self` parameters on such methods.
+///
 /// ## Example
 /// ```python
 /// class Person:
@@ -38,6 +48,8 @@ use crate::rules::flake8_unused_arguments::rules::is_not_implemented_stub_with_v
 ///     def greeting():
 ///         print("Greetings friend!")
 /// ```
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(preview_since = "v0.0.286")]
 pub(crate) struct NoSelfUse {

crates/ruff_linter/src/rules/pylint/rules/too_many_arguments.rs

@@ -12,6 +12,16 @@ use crate::checkers::ast::Checker;
 /// By default, this rule allows up to five arguments, as configured by the
 /// [`lint.pylint.max-args`] option.
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override].
+/// Changing the signature of a subclass method may cause type checkers to
+/// complain about a violation of the Liskov Substitution Principle if it
+/// means that the method now incompatibly overrides a method defined on a
+/// superclass. Explicitly decorating an overriding method with `@override`
+/// signals to Ruff that the method is intended to override a superclass
+/// method and that a type checker will enforce that it does so; Ruff
+/// therefore knows that it should not enforce rules about methods having
+/// too many arguments.
+///
 /// ## Why is this bad?
 /// Functions with many arguments are harder to understand, maintain, and call.
 /// Consider refactoring functions with many arguments into smaller functions
@@ -43,6 +53,8 @@ use crate::checkers::ast::Checker;
 ///
 /// ## Options
 /// - `lint.pylint.max-args`
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(stable_since = "v0.0.238")]
 pub(crate) struct TooManyArguments {

crates/ruff_linter/src/rules/pylint/rules/too_many_positional_arguments.rs

@@ -21,6 +21,16 @@ use crate::checkers::ast::Checker;
 /// with fewer arguments, using objects to group related arguments, or migrating to
 /// [keyword-only arguments](https://docs.python.org/3/tutorial/controlflow.html#special-parameters).
 ///
+/// This rule exempts methods decorated with [`@typing.override`][override].
+/// Changing the signature of a subclass method may cause type checkers to
+/// complain about a violation of the Liskov Substitution Principle if it
+/// means that the method now incompatibly overrides a method defined on a
+/// superclass. Explicitly decorating an overriding method with `@override`
+/// signals to Ruff that the method is intended to override a superclass
+/// method and that a type checker will enforce that it does so; Ruff
+/// therefore knows that it should not enforce rules about methods having
+/// too many arguments.
+///
 /// ## Example
 ///
 /// ```python
@@ -41,6 +51,8 @@ use crate::checkers::ast::Checker;
 ///
 /// ## Options
 /// - `lint.pylint.max-positional-args`
+///
+/// [override]: https://docs.python.org/3/library/typing.html#typing.override
 #[derive(ViolationMetadata)]
 #[violation_metadata(preview_since = "v0.1.7")]
 pub(crate) struct TooManyPositionalArguments {

crates/ty_python_semantic/src/types/diagnostic.rs

@@ -2072,7 +2072,27 @@ declare_lint! {
     /// be avoided wherever possible. As part of this check, therefore, ty enforces that `__eq__`
     /// and `__ne__` methods accept `object` as their second argument.
     ///
+    /// ### Why does ty disagree with Ruff about how to write my method?
+    ///
+    /// Ruff has several rules that will encourage you to rename a parameter, or change its type
+    /// signature, if it thinks you're falling into a certain anti-pattern. For example, Ruff's
+    /// [ARG002](https://docs.astral.sh/ruff/rules/unused-method-argument/) rule recommends that an
+    /// unused parameter should either be removed or renamed to start with `_`. Applying either of
+    /// these suggestions can cause ty to start reporting an `invalid-method-override` error if
+    /// the function in question is a method on a subclass that overrides a method on a superclass,
+    /// and the change would cause the subclass method to no longer accept all argument combinations
+    /// that the superclass method accepts.
+    ///
+    /// This can usually be resolved by adding [`@typing.override`][override] to your method
+    /// definition. Ruff knows that a method decorated with `@typing.override` is intended to
+    /// override a method by the same name on a superclass, and avoids reporting rules like ARG002
+    /// for such methods; it knows that the changes recommended by ARG002 would violate the Liskov
+    /// Substitution Principle.
+    ///
+    /// Correct use of `@override` is enforced by ty's `invalid-explicit-override` rule.
+    ///
     /// [Liskov Substitution Principle]: https://en.wikipedia.org/wiki/Liskov_substitution_principle
+    /// [override]: https://docs.python.org/3/library/typing.html#typing.override
     pub(crate) static INVALID_METHOD_OVERRIDE = {
         summary: "detects method definitions that violate the Liskov Substitution Principle",
         status: LintStatus::stable("0.0.1-alpha.20"),