Stabilize generic-not-last-base-class (PYI059)

crates/ruff_linter/src/codes.rs

@@ -809,7 +809,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Flake8Pyi, "056") => (RuleGroup::Stable, rules::flake8_pyi::rules::UnsupportedMethodCallOnAll),
         (Flake8Pyi, "058") => (RuleGroup::Stable, rules::flake8_pyi::rules::GeneratorReturnFromIterMethod),
         (Flake8Pyi, "057") => (RuleGroup::Stable, rules::flake8_pyi::rules::ByteStringUsage),
-        (Flake8Pyi, "059") => (RuleGroup::Preview, rules::flake8_pyi::rules::GenericNotLastBaseClass),
+        (Flake8Pyi, "059") => (RuleGroup::Stable, rules::flake8_pyi::rules::GenericNotLastBaseClass),
         (Flake8Pyi, "061") => (RuleGroup::Preview, rules::flake8_pyi::rules::RedundantNoneLiteral),
         (Flake8Pyi, "062") => (RuleGroup::Stable, rules::flake8_pyi::rules::DuplicateLiteralMember),
         (Flake8Pyi, "063") => (RuleGroup::Stable, rules::flake8_pyi::rules::Pep484StylePositionalOnlyParameter),

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

@@ -11,10 +11,14 @@ use crate::{Fix, FixAvailability, Violation};
 /// not the last base class in the bases tuple.
 ///
 /// ## Why is this bad?
+///
 /// If `Generic[]` is not the final class in the bases tuple, unexpected
 /// behaviour can occur at runtime (See [this CPython issue][1] for an example).
-/// The rule is also applied to stub files, but, unlike at runtime,
-/// in stubs it is purely enforced for stylistic consistency.
+///
+/// The rule is also applied to stub files, where it won't cause issues at
+/// runtime. This is because type checkers may not be able to infer an
+/// accurate [MRO] for the class, which could lead to unexpected or
+/// inaccurate results when they analyze your code.
 ///
 /// For example:
 /// ```python
@@ -47,6 +51,7 @@ use crate::{Fix, FixAvailability, Violation};
 /// - [`typing.Generic` documentation](https://docs.python.org/3/library/typing.html#typing.Generic)
 ///
 /// [1]: https://github.com/python/cpython/issues/106102
+/// [MRO]: https://docs.python.org/3/glossary.html#term-method-resolution-order
 #[derive(ViolationMetadata)]
 pub(crate) struct GenericNotLastBaseClass;