Fix various lint (#16726)

.pre-commit-config.yaml

@@ -10,7 +10,7 @@ repos:
     hooks:
       - id: black
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.1.0  # must match test-requirements.txt
+    rev: v0.1.4  # must match test-requirements.txt
     hooks:
       - id: ruff
         args: [--exit-non-zero-on-fix]

mypy/binder.py

@@ -291,7 +291,7 @@ def assign_type(
             self.type_assignments[expr].append((type, declared_type))
             return
         if not isinstance(expr, (IndexExpr, MemberExpr, NameExpr)):
-            return None
+            return
         if not literal(expr):
             return
         self.invalidate_dependencies(expr)

mypy/build.py

@@ -682,9 +682,7 @@ def __init__(
         # for efficient lookup
         self.shadow_map: dict[str, str] = {}
         if self.options.shadow_file is not None:
-            self.shadow_map = {
-                source_file: shadow_file for (source_file, shadow_file) in self.options.shadow_file
-            }
+            self.shadow_map = dict(self.options.shadow_file)
         # a mapping from each file being typechecked to its possible shadow file
         self.shadow_equivalence_map: dict[str, str | None] = {}
         self.plugin = plugin
@@ -1120,7 +1118,7 @@ def read_deps_cache(manager: BuildManager, graph: Graph) -> dict[str, FgDepMeta]
     module_deps_metas = deps_meta["deps_meta"]
     assert isinstance(module_deps_metas, dict)
     if not manager.options.skip_cache_mtime_checks:
-        for id, meta in module_deps_metas.items():
+        for meta in module_deps_metas.values():
             try:
                 matched = manager.getmtime(meta["path"]) == meta["mtime"]
             except FileNotFoundError:
@@ -2093,7 +2091,7 @@ def load_tree(self, temporary: bool = False) -> None:
             self.meta.data_json, self.manager, "Load tree ", "Could not load tree: "
         )
         if data is None:
-            return None
+            return
 
         t0 = time.time()
         # TODO: Assert data file wasn't changed.
@@ -3383,7 +3381,7 @@ def order_ascc(graph: Graph, ascc: AbstractSet[str], pri_max: int = PRI_ALL) ->
     strongly_connected_components() below for a reference.
     """
     if len(ascc) == 1:
-        return [s for s in ascc]
+        return list(ascc)
     pri_spread = set()
     for id in ascc:
         state = graph[id]

mypy/checker.py

@@ -632,7 +632,7 @@ def _visit_overloaded_func_def(self, defn: OverloadedFuncDef) -> None:
         if not defn.items:
             # In this case we have already complained about none of these being
             # valid overloads.
-            return None
+            return
         if len(defn.items) == 1:
             self.fail(message_registry.MULTIPLE_OVERLOADS_REQUIRED, defn)
 
@@ -676,7 +676,6 @@ def _visit_overloaded_func_def(self, defn: OverloadedFuncDef) -> None:
                 self.msg.no_overridable_method(defn.name, defn)
             self.check_explicit_override_decorator(defn, found_method_base_classes, defn.impl)
             self.check_inplace_operator_method(defn)
-        return None
 
     def extract_callable_type(self, inner_type: Type | None, ctx: Context) -> CallableType | None:
         """Get type as seen by an overload item caller."""
@@ -1838,7 +1837,7 @@ def check_match_args(self, var: Var, typ: Type, context: Context) -> None:
             return
         typ = get_proper_type(typ)
         if not isinstance(typ, TupleType) or not all(
-            [is_string_literal(item) for item in typ.items]
+            is_string_literal(item) for item in typ.items
         ):
             self.msg.note(
                 "__match_args__ must be a tuple containing string literals for checking "
@@ -5045,7 +5044,7 @@ def visit_break_stmt(self, s: BreakStmt) -> None:
 
     def visit_continue_stmt(self, s: ContinueStmt) -> None:
         self.binder.handle_continue()
-        return None
+        return
 
     def visit_match_stmt(self, s: MatchStmt) -> None:
         with self.binder.frame_context(can_skip=False, fall_through=0):

mypy/checkexpr.py

@@ -739,7 +739,7 @@ def check_typeddict_call(
         context: Context,
         orig_callee: Type | None,
     ) -> Type:
-        if args and all([ak in (ARG_NAMED, ARG_STAR2) for ak in arg_kinds]):
+        if args and all(ak in (ARG_NAMED, ARG_STAR2) for ak in arg_kinds):
             # ex: Point(x=42, y=1337, **extras)
             # This is a bit ugly, but this is a price for supporting all possible syntax
             # variants for TypedDict constructors.
@@ -4017,9 +4017,7 @@ def check_op(
             left_variants = [base_type]
             base_type = get_proper_type(base_type)
             if isinstance(base_type, UnionType):
-                left_variants = [
-                    item for item in flatten_nested_unions(base_type.relevant_items())
-                ]
+                left_variants = list(flatten_nested_unions(base_type.relevant_items()))
             right_type = self.accept(arg)
 
             # Step 1: We first try leaving the right arguments alone and destructure

mypy/checkpattern.py

@@ -187,7 +187,7 @@ def visit_or_pattern(self, o: OrPattern) -> PatternType:
                 capture_types[node].append((expr, typ))
 
         captures: dict[Expression, Type] = {}
-        for var, capture_list in capture_types.items():
+        for capture_list in capture_types.values():
             typ = UninhabitedType()
             for _, other in capture_list:
                 typ = join_types(typ, other)

mypy/checkstrformat.py

@@ -372,7 +372,7 @@ def check_specs_in_format_call(
                 ):
                     # TODO: add support for some custom specs like datetime?
                     self.msg.fail(
-                        "Unrecognized format" ' specification "{}"'.format(spec.format_spec[1:]),
+                        f'Unrecognized format specification "{spec.format_spec[1:]}"',
                         call,
                         code=codes.STRING_FORMATTING,
                     )
@@ -482,7 +482,7 @@ def find_replacements_in_call(self, call: CallExpr, keys: list[str]) -> list[Exp
                 expr = self.get_expr_by_name(key, call)
                 if not expr:
                     self.msg.fail(
-                        "Cannot find replacement for named" ' format specifier "{}"'.format(key),
+                        f'Cannot find replacement for named format specifier "{key}"',
                         call,
                         code=codes.STRING_FORMATTING,
                     )

mypy/dmypy_server.py

@@ -1055,7 +1055,7 @@ def fix_module_deps(graph: mypy.build.Graph) -> None:
     This can make some suppressed dependencies non-suppressed, and vice versa (if modules
     have been added to or removed from the build).
     """
-    for module, state in graph.items():
+    for state in graph.values():
         new_suppressed = []
         new_dependencies = []
         for dep in state.dependencies + state.suppressed:

mypy/dmypy_util.py

@@ -43,7 +43,7 @@ def send(connection: IPCBase, data: Any) -> None:
 class WriteToConn:
     """Helper class to write to a connection instead of standard output."""
 
-    def __init__(self, server: IPCBase, output_key: str = "stdout"):
+    def __init__(self, server: IPCBase, output_key: str = "stdout") -> None:
         self.server = server
         self.output_key = output_key
 

mypy/errors.py

@@ -170,7 +170,7 @@ def __init__(
         *,
         filter_errors: bool | Callable[[str, ErrorInfo], bool] = False,
         save_filtered_errors: bool = False,
-    ):
+    ) -> None:
         self.errors = errors
         self._has_new_errors = False
         self._filter = filter_errors

mypy/main.py

@@ -145,7 +145,7 @@ def main(
         sys.exit(code)
 
     # HACK: keep res alive so that mypyc won't free it before the hard_exit
-    list([res])
+    list([res])  # noqa: C410
 
 
 def run_build(
@@ -349,7 +349,7 @@ class CapturableArgumentParser(argparse.ArgumentParser):
     yet output must be captured to properly support mypy.api.run.
     """
 
-    def __init__(self, *args: Any, **kwargs: Any):
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
         self.stdout = kwargs.pop("stdout", sys.stdout)
         self.stderr = kwargs.pop("stderr", sys.stderr)
         super().__init__(*args, **kwargs)
@@ -415,7 +415,7 @@ def __init__(
         default: str = argparse.SUPPRESS,
         help: str = "show program's version number and exit",
         stdout: IO[str] | None = None,
-    ):
+    ) -> None:
         super().__init__(
             option_strings=option_strings, dest=dest, default=default, nargs=0, help=help
         )

mypy/message_registry.py

@@ -52,7 +52,7 @@ def with_additional_msg(self, info: str) -> ErrorMessage:
     '"return" with value in async generator is not allowed'
 )
 INVALID_RETURN_TYPE_FOR_GENERATOR: Final = ErrorMessage(
-    'The return type of a generator function should be "Generator"' " or one of its supertypes"
+    'The return type of a generator function should be "Generator" or one of its supertypes'
 )
 INVALID_RETURN_TYPE_FOR_ASYNC_GENERATOR: Final = ErrorMessage(
     'The return type of an async generator function should be "AsyncGenerator" or one of its '

mypy/messages.py

@@ -3099,7 +3099,7 @@ def append_invariance_notes(
     ):
         invariant_type = "Dict"
         covariant_suggestion = (
-            'Consider using "Mapping" instead, ' "which is covariant in the value type"
+            'Consider using "Mapping" instead, which is covariant in the value type'
         )
     if invariant_type and covariant_suggestion:
         notes.append(

mypy/nodes.py

@@ -3137,7 +3137,7 @@ def protocol_members(self) -> list[str]:
                     if name in EXCLUDED_PROTOCOL_ATTRIBUTES:
                         continue
                     members.add(name)
-        return sorted(list(members))
+        return sorted(members)
 
     def __getitem__(self, name: str) -> SymbolTableNode:
         n = self.get(name)
@@ -3296,7 +3296,7 @@ def serialize(self) -> JsonDict:
             else self.typeddict_type.serialize(),
             "flags": get_flags(self, TypeInfo.FLAGS),
             "metadata": self.metadata,
-            "slots": list(sorted(self.slots)) if self.slots is not None else None,
+            "slots": sorted(self.slots) if self.slots is not None else None,
             "deletable_attributes": self.deletable_attributes,
             "self_type": self.self_type.serialize() if self.self_type is not None else None,
             "dataclass_transform_spec": (
@@ -3966,7 +3966,7 @@ def __init__(
         # frozen_default was added to CPythonin https://github.com/python/cpython/pull/99958 citing
         # positive discussion in typing-sig
         frozen_default: bool | None = None,
-    ):
+    ) -> None:
         self.eq_default = eq_default if eq_default is not None else True
         self.order_default = order_default if order_default is not None else False
         self.kw_only_default = kw_only_default if kw_only_default is not None else False

mypy/patterns.py

@@ -60,7 +60,7 @@ class ValuePattern(Pattern):
 
     expr: Expression
 
-    def __init__(self, expr: Expression):
+    def __init__(self, expr: Expression) -> None:
         super().__init__()
         self.expr = expr
 
@@ -72,7 +72,7 @@ class SingletonPattern(Pattern):
     # This can be exactly True, False or None
     value: bool | None
 
-    def __init__(self, value: bool | None):
+    def __init__(self, value: bool | None) -> None:
         super().__init__()
         self.value = value
 
@@ -85,7 +85,7 @@ class SequencePattern(Pattern):
 
     patterns: list[Pattern]
 
-    def __init__(self, patterns: list[Pattern]):
+    def __init__(self, patterns: list[Pattern]) -> None:
         super().__init__()
         self.patterns = patterns
 
@@ -98,7 +98,7 @@ class StarredPattern(Pattern):
     # a name.
     capture: NameExpr | None
 
-    def __init__(self, capture: NameExpr | None):
+    def __init__(self, capture: NameExpr | None) -> None:
         super().__init__()
         self.capture = capture
 
@@ -111,7 +111,9 @@ class MappingPattern(Pattern):
     values: list[Pattern]
     rest: NameExpr | None
 
-    def __init__(self, keys: list[Expression], values: list[Pattern], rest: NameExpr | None):
+    def __init__(
+        self, keys: list[Expression], values: list[Pattern], rest: NameExpr | None
+    ) -> None:
         super().__init__()
         assert len(keys) == len(values)
         self.keys = keys
@@ -136,7 +138,7 @@ def __init__(
         positionals: list[Pattern],
         keyword_keys: list[str],
         keyword_values: list[Pattern],
-    ):
+    ) -> None:
         super().__init__()
         assert len(keyword_keys) == len(keyword_values)
         self.class_ref = class_ref

mypy/plugins/enums.py

@@ -166,11 +166,11 @@ class SomeEnum:
                 for n in stnodes
                 if n is None or not n.implicit
             )
-            proper_types = list(
+            proper_types = [
                 _infer_value_type_with_auto_fallback(ctx, t)
                 for t in node_types
                 if t is None or not isinstance(t, CallableType)
-            )
+            ]
             underlying_type = _first(proper_types)
             if underlying_type is None:
                 return ctx.default_attr_type

mypy/renaming.py

@@ -270,7 +270,7 @@ def flush_refs(self) -> None:
         This will be called at the end of a scope.
         """
         is_func = self.scope_kinds[-1] == FUNCTION
-        for name, refs in self.refs[-1].items():
+        for refs in self.refs[-1].values():
             if len(refs) == 1:
                 # Only one definition -- no renaming needed.
                 continue

mypy/semanal.py

@@ -4153,7 +4153,7 @@ def check_typevarlike_name(self, call: CallExpr, name: str, context: Context) ->
         if len(call.args) < 1:
             self.fail(f"Too few arguments for {typevarlike_type}()", context)
             return False
-        if not isinstance(call.args[0], StrExpr) or not call.arg_kinds[0] == ARG_POS:
+        if not isinstance(call.args[0], StrExpr) or call.arg_kinds[0] != ARG_POS:
             self.fail(f"{typevarlike_type}() expects a string literal as first argument", context)
             return False
         elif call.args[0].value != name:
@@ -4961,9 +4961,7 @@ def visit_name_expr(self, expr: NameExpr) -> None:
     def bind_name_expr(self, expr: NameExpr, sym: SymbolTableNode) -> None:
         """Bind name expression to a symbol table node."""
         if isinstance(sym.node, TypeVarExpr) and self.tvar_scope.get_binding(sym):
-            self.fail(
-                '"{}" is a type variable and only valid in type ' "context".format(expr.name), expr
-            )
+            self.fail(f'"{expr.name}" is a type variable and only valid in type context', expr)
         elif isinstance(sym.node, PlaceholderNode):
             self.process_placeholder(expr.name, "name", expr)
         else:
@@ -6809,13 +6807,13 @@ def parse_dataclass_transform_spec(self, call: CallExpr) -> DataclassTransformSp
     def parse_dataclass_transform_field_specifiers(self, arg: Expression) -> tuple[str, ...]:
         if not isinstance(arg, TupleExpr):
             self.fail('"field_specifiers" argument must be a tuple literal', arg)
-            return tuple()
+            return ()
 
         names = []
         for specifier in arg.items:
             if not isinstance(specifier, RefExpr):
                 self.fail('"field_specifiers" must only contain identifiers', specifier)
-                return tuple()
+                return ()
             names.append(specifier.fullname)
         return tuple(names)
 

mypy/semanal_enum.py

@@ -148,7 +148,7 @@ def parse_enum_call_args(
         Return a tuple of fields, values, was there an error.
         """
         args = call.args
-        if not all([arg_kind in [ARG_POS, ARG_NAMED] for arg_kind in call.arg_kinds]):
+        if not all(arg_kind in [ARG_POS, ARG_NAMED] for arg_kind in call.arg_kinds):
             return self.fail_enum_call_arg(f"Unexpected arguments to {class_name}()", call)
         if len(args) < 2:
             return self.fail_enum_call_arg(f"Too few arguments for {class_name}()", call)

mypy/semanal_namedtuple.py

@@ -85,7 +85,7 @@
 )
 
 NAMEDTUP_CLASS_ERROR: Final = (
-    "Invalid statement in NamedTuple definition; " 'expected "field_name: field_type [= default]"'
+    'Invalid statement in NamedTuple definition; expected "field_name: field_type [= default]"'
 )
 
 SELF_TVAR_NAME: Final = "_NT"

mypy/semanal_typeddict.py

@@ -50,7 +50,7 @@
 )
 
 TPDICT_CLASS_ERROR: Final = (
-    "Invalid statement in TypedDict definition; " 'expected "field_name: field_type"'
+    'Invalid statement in TypedDict definition; expected "field_name: field_type"'
 )
 
 

mypy/server/astmerge.py

@@ -394,7 +394,7 @@ def process_synthetic_type_info(self, info: TypeInfo) -> None:
         # have bodies in the AST so we need to iterate over their symbol
         # tables separately, unlike normal classes.
         self.process_type_info(info)
-        for name, node in info.names.items():
+        for node in info.names.values():
             if node.node:
                 node.node.accept(self)
 
@@ -549,7 +549,7 @@ def fixup(self, node: SN) -> SN:
 def replace_nodes_in_symbol_table(
     symbols: SymbolTable, replacements: dict[SymbolNode, SymbolNode]
 ) -> None:
-    for name, node in symbols.items():
+    for node in symbols.values():
         if node.node:
             if node.node in replacements:
                 new = replacements[node.node]