Merge branch 'master' into fix-enum-with-property-match-exhaustion

.github/workflows/docs.yml

@@ -36,7 +36,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
-          python-version: '3.8'
+          python-version: '3.12'
       - name: Install tox
         run: pip install tox==4.11.0
       - name: Setup tox environment

docs/requirements-docs.txt

@@ -1,2 +1,3 @@
 sphinx>=5.1.0
 furo>=2022.3.4
+myst-parser>=4.0.0

docs/source/changelog.md

@@ -0,0 +1,3 @@
+<!-- This file includes mypy/CHANGELOG.md into mypy documentation -->
+```{include} ../../CHANGELOG.md
+```

docs/source/conf.py

@@ -35,7 +35,7 @@
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
-extensions = ["sphinx.ext.intersphinx", "docs.source.html_builder"]
+extensions = ["sphinx.ext.intersphinx", "docs.source.html_builder", "myst_parser"]
 
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ["_templates"]

docs/source/error_code_list.rst

@@ -1149,6 +1149,34 @@ types you expect.
 
 See :ref:`overloading <function-overloading>` for more explanation.
 
+
+.. _code-overload-cannot-match:
+
+Check for overload signatures that cannot match [overload-cannot-match]
+--------------------------------------------------------------------------
+
+Warn if an ``@overload`` variant can never be matched, because an earlier
+overload has a wider signature. For example, this can happen if the two
+overloads accept the same parameters and each parameter on the first overload
+has the same type or a wider type than the corresponding parameter on the second
+overload.
+
+Example:
+
+.. code-block:: python
+
+    from typing import overload, Union
+
+    @overload
+    def process(response1: object, response2: object) -> object:
+        ...
+    @overload
+    def process(response1: int, response2: int) -> int: # E: Overloaded function signature 2 will never be matched: signature 1's parameter type(s) are the same or broader  [overload-cannot-match]
+        ...
+
+    def process(response1: object, response2: object) -> object:
+        return response1 + response2
+
 .. _code-annotation-unchecked:
 
 Notify about an annotation in an unchecked function [annotation-unchecked]

docs/source/index.rst

@@ -103,6 +103,7 @@ Contents
    error_code_list2
    additional_features
    faq
+   changelog
 
 .. toctree::
    :hidden:

misc/typeshed_patches/0001-Revert-sum-literal-integer-change-13961.patch

@@ -1,4 +1,4 @@
-From 44bc98bd50e7170887f0740b53ed95a8eb04f00e Mon Sep 17 00:00:00 2001
+From 58c6a6ab863c1c38e95ccafaf13792ed9c00e499 Mon Sep 17 00:00:00 2001
 From: Shantanu <[email protected]>
 Date: Sat, 29 Oct 2022 12:47:21 -0700
 Subject: [PATCH] Revert sum literal integer change (#13961)
@@ -19,18 +19,18 @@ within mypy, I might pursue upstreaming this in typeshed.
  1 file changed, 1 insertion(+), 1 deletion(-)
 
 diff --git a/mypy/typeshed/stdlib/builtins.pyi b/mypy/typeshed/stdlib/builtins.pyi
-index 99919c64c..680cd5561 100644
+index ea9f8c894..a6065cc67 100644
 --- a/mypy/typeshed/stdlib/builtins.pyi
 +++ b/mypy/typeshed/stdlib/builtins.pyi
-@@ -1596,7 +1596,7 @@ _SupportsSumNoDefaultT = TypeVar("_SupportsSumNoDefaultT", bound=_SupportsSumWit
+@@ -1653,7 +1653,7 @@ _SupportsSumNoDefaultT = TypeVar("_SupportsSumNoDefaultT", bound=_SupportsSumWit
  # without creating many false-positive errors (see #7578).
  # Instead, we special-case the most common examples of this: bool and literal integers.
  @overload
--def sum(iterable: Iterable[bool | _LiteralInteger], /, start: int = 0) -> int: ...  # type: ignore[overload-overlap]
-+def sum(iterable: Iterable[bool], /, start: int = 0) -> int: ...  # type: ignore[overload-overlap]
+-def sum(iterable: Iterable[bool | _LiteralInteger], /, start: int = 0) -> int: ...
++def sum(iterable: Iterable[bool], /, start: int = 0) -> int: ...
  @overload
  def sum(iterable: Iterable[_SupportsSumNoDefaultT], /) -> _SupportsSumNoDefaultT | Literal[0]: ...
  @overload
 -- 
-2.39.3 (Apple Git-146)
+2.46.0
 

mypy/checker.py

@@ -683,6 +683,8 @@ def extract_callable_type(self, inner_type: Type | None, ctx: Context) -> Callab
         inner_type = get_proper_type(inner_type)
         outer_type: CallableType | None = None
         if inner_type is not None and not isinstance(inner_type, AnyType):
+            if isinstance(inner_type, TypeVarLikeType):
+                inner_type = get_proper_type(inner_type.upper_bound)
             if isinstance(inner_type, TypeType):
                 if isinstance(inner_type.item, Instance):
                     inner_type = expand_type_by_instance(
@@ -5649,7 +5651,16 @@ def _is_truthy_type(self, t: ProperType) -> bool:
             )
         )
 
-    def _check_for_truthy_type(self, t: Type, expr: Expression) -> None:
+    def check_for_truthy_type(self, t: Type, expr: Expression) -> None:
+        """
+        Check if a type can have a truthy value.
+
+        Used in checks like::
+
+            if x: # <---
+
+            not x  # <---
+        """
         if not state.strict_optional:
             return  # if everything can be None, all bets are off
 
@@ -6143,7 +6154,7 @@ def has_no_custom_eq_checks(t: Type) -> bool:
         if in_boolean_context:
             # We don't check `:=` values in expressions like `(a := A())`,
             # because they produce two error messages.
-            self._check_for_truthy_type(original_vartype, node)
+            self.check_for_truthy_type(original_vartype, node)
         vartype = try_expanding_sum_type_to_union(original_vartype, "builtins.bool")
 
         if_type = true_only(vartype)

mypy/checkexpr.py

@@ -4256,6 +4256,7 @@ def visit_unary_expr(self, e: UnaryExpr) -> Type:
         op = e.op
         if op == "not":
             result: Type = self.bool_type()
+            self.chk.check_for_truthy_type(operand_type, e.expr)
         else:
             method = operators.unary_op_methods[op]
             result, method_type = self.check_method_call_by_name(method, operand_type, [], [], e)

mypy/errorcodes.py

@@ -273,6 +273,14 @@ def __hash__(self) -> int:
 # This is a catch-all for remaining uncategorized errors.
 MISC: Final[ErrorCode] = ErrorCode("misc", "Miscellaneous other checks", "General")
 
+OVERLOAD_CANNOT_MATCH: Final[ErrorCode] = ErrorCode(
+    "overload-cannot-match",
+    "Warn if an @overload signature can never be matched",
+    "General",
+    sub_code_of=MISC,
+)
+
+
 OVERLOAD_OVERLAP: Final[ErrorCode] = ErrorCode(
     "overload-overlap",
     "Warn if multiple @overload variants overlap in unsafe ways",

mypy/exprtotype.py

@@ -2,12 +2,15 @@
 
 from __future__ import annotations
 
+from typing import Callable
+
 from mypy.fastparse import parse_type_string
 from mypy.nodes import (
     MISSING_FALLBACK,
     BytesExpr,
     CallExpr,
     ComplexExpr,
+    Context,
     DictExpr,
     EllipsisExpr,
     Expression,
@@ -21,6 +24,7 @@
     RefExpr,
     StarExpr,
     StrExpr,
+    SymbolTableNode,
     TupleExpr,
     UnaryExpr,
     get_member_expr_fullname,
@@ -63,12 +67,16 @@ def expr_to_unanalyzed_type(
     allow_new_syntax: bool = False,
     _parent: Expression | None = None,
     allow_unpack: bool = False,
+    lookup_qualified: Callable[[str, Context], SymbolTableNode | None] | None = None,
 ) -> ProperType:
     """Translate an expression to the corresponding type.
 
     The result is not semantically analyzed. It can be UnboundType or TypeList.
     Raise TypeTranslationError if the expression cannot represent a type.
 
+    If lookup_qualified is not provided, the expression is expected to be semantically
+    analyzed.
+
     If allow_new_syntax is True, allow all type syntax independent of the target
     Python version (used in stubs).
 
@@ -101,19 +109,26 @@ def expr_to_unanalyzed_type(
             else:
                 args = [expr.index]
 
-            if isinstance(expr.base, RefExpr) and expr.base.fullname in ANNOTATED_TYPE_NAMES:
-                # TODO: this is not the optimal solution as we are basically getting rid
-                # of the Annotation definition and only returning the type information,
-                # losing all the annotations.
+            if isinstance(expr.base, RefExpr):
+                # Check if the type is Annotated[...]. For this we need the fullname,
+                # which must be looked up if the expression hasn't been semantically analyzed.
+                base_fullname = None
+                if lookup_qualified is not None:
+                    sym = lookup_qualified(base.name, expr)
+                    if sym and sym.node:
+                        base_fullname = sym.node.fullname
+                else:
+                    base_fullname = expr.base.fullname
 
-                return expr_to_unanalyzed_type(args[0], options, allow_new_syntax, expr)
-            else:
-                base.args = tuple(
-                    expr_to_unanalyzed_type(
-                        arg, options, allow_new_syntax, expr, allow_unpack=True
-                    )
-                    for arg in args
-                )
+                if base_fullname is not None and base_fullname in ANNOTATED_TYPE_NAMES:
+                    # TODO: this is not the optimal solution as we are basically getting rid
+                    # of the Annotation definition and only returning the type information,
+                    # losing all the annotations.
+                    return expr_to_unanalyzed_type(args[0], options, allow_new_syntax, expr)
+            base.args = tuple(
+                expr_to_unanalyzed_type(arg, options, allow_new_syntax, expr, allow_unpack=True)
+                for arg in args
+            )
             if not base.args:
                 base.empty_tuple_index = True
             return base

mypy/fastparse.py

@@ -331,12 +331,10 @@ def parse_type_string(
     """
     try:
         _, node = parse_type_comment(f"({expr_string})", line=line, column=column, errors=None)
-        if isinstance(node, UnboundType) and node.original_str_expr is None:
+        if isinstance(node, (UnboundType, UnionType)) and node.original_str_expr is None:
             node.original_str_expr = expr_string
             node.original_str_fallback = expr_fallback_name
             return node
-        elif isinstance(node, UnionType):
-            return node
         else:
             return RawExpressionType(expr_string, expr_fallback_name, line, column)
     except (SyntaxError, ValueError):

mypy/messages.py

@@ -1653,6 +1653,7 @@ def overloaded_signature_will_never_match(
                 index1=index1, index2=index2
             ),
             context,
+            code=codes.OVERLOAD_CANNOT_MATCH,
         )
 
     def overloaded_signatures_typevar_specific(self, index: int, context: Context) -> None:

mypy/report.py

@@ -689,6 +689,8 @@ def on_finish(self) -> None:
             self.root_package.covered_lines, self.root_package.total_lines
         )
         self.root.attrib["branch-rate"] = "0"
+        self.root.attrib["lines-covered"] = str(self.root_package.covered_lines)
+        self.root.attrib["lines-valid"] = str(self.root_package.total_lines)
         sources = etree.SubElement(self.root, "sources")
         source_element = etree.SubElement(sources, "source")
         source_element.text = os.getcwd()

mypy/semanal.py

@@ -824,6 +824,11 @@ def file_context(
             self.num_incomplete_refs = 0
 
             if active_type:
+                enclosing_fullname = active_type.fullname.rsplit(".", 1)[0]
+                if "." in enclosing_fullname:
+                    enclosing_node = self.lookup_fully_qualified_or_none(enclosing_fullname)
+                    if enclosing_node and isinstance(enclosing_node.node, TypeInfo):
+                        self._type = enclosing_node.node
                 self.push_type_args(active_type.defn.type_args, active_type.defn)
                 self.incomplete_type_stack.append(False)
                 scope.enter_class(active_type)
@@ -3744,7 +3749,9 @@ def analyze_alias(
         dynamic = bool(self.function_stack and self.function_stack[-1].is_dynamic())
         global_scope = not self.type and not self.function_stack
         try:
-            typ = expr_to_unanalyzed_type(rvalue, self.options, self.is_stub_file)
+            typ = expr_to_unanalyzed_type(
+                rvalue, self.options, self.is_stub_file, lookup_qualified=self.lookup_qualified
+            )
         except TypeTranslationError:
             self.fail(
                 "Invalid type alias: expression is not a valid type", rvalue, code=codes.VALID_TYPE
@@ -6951,6 +6958,7 @@ def name_not_defined(self, name: str, ctx: Context, namespace: str | None = None
             namespace is None
             and self.type
             and not self.is_func_scope()
+            and self.incomplete_type_stack
             and self.incomplete_type_stack[-1]
             and not self.final_iteration
         ):

mypy/stubgen.py

@@ -54,6 +54,7 @@
 import mypy.parse
 import mypy.traverser
 import mypy.util
+import mypy.version
 from mypy.build import build
 from mypy.errors import CompileError, Errors
 from mypy.find_sources import InvalidSourceList, create_source_list
@@ -304,9 +305,26 @@ def visit_name_expr(self, node: NameExpr) -> str:
     def visit_member_expr(self, o: MemberExpr) -> str:
         return self._visit_ref_expr(o)
 
-    def visit_str_expr(self, node: StrExpr) -> str:
+    def _visit_literal_node(
+        self, node: StrExpr | BytesExpr | IntExpr | FloatExpr | ComplexExpr
+    ) -> str:
         return repr(node.value)
 
+    def visit_str_expr(self, node: StrExpr) -> str:
+        return self._visit_literal_node(node)
+
+    def visit_bytes_expr(self, node: BytesExpr) -> str:
+        return f"b{self._visit_literal_node(node)}"
+
+    def visit_int_expr(self, node: IntExpr) -> str:
+        return self._visit_literal_node(node)
+
+    def visit_float_expr(self, node: FloatExpr) -> str:
+        return self._visit_literal_node(node)
+
+    def visit_complex_expr(self, node: ComplexExpr) -> str:
+        return self._visit_literal_node(node)
+
     def visit_index_expr(self, node: IndexExpr) -> str:
         base_fullname = self.stubgen.get_fullname(node.base)
         if base_fullname == "typing.Union":
@@ -570,8 +588,8 @@ def _get_func_return(self, o: FuncDef, ctx: FunctionContext) -> str | None:
         if has_yield_expression(o) or has_yield_from_expression(o):
             generator_name = self.add_name("collections.abc.Generator")
             yield_name = "None"
-            send_name = "None"
-            return_name = "None"
+            send_name: str | None = None
+            return_name: str | None = None
             if has_yield_from_expression(o):
                 yield_name = send_name = self.add_name("_typeshed.Incomplete")
             else:
@@ -582,7 +600,14 @@ def _get_func_return(self, o: FuncDef, ctx: FunctionContext) -> str | None:
                         send_name = self.add_name("_typeshed.Incomplete")
             if has_return_statement(o):
                 return_name = self.add_name("_typeshed.Incomplete")
-            return f"{generator_name}[{yield_name}, {send_name}, {return_name}]"
+            if return_name is not None:
+                if send_name is None:
+                    send_name = "None"
+                return f"{generator_name}[{yield_name}, {send_name}, {return_name}]"
+            elif send_name is not None:
+                return f"{generator_name}[{yield_name}, {send_name}]"
+            else:
+                return f"{generator_name}[{yield_name}]"
         if not has_return_statement(o) and o.abstract_status == NOT_ABSTRACT:
             return "None"
         return None
@@ -804,7 +829,8 @@ def get_base_types(self, cdef: ClassDef) -> list[str]:
         for name, value in cdef.keywords.items():
             if name == "metaclass":
                 continue  # handled separately
-            base_types.append(f"{name}={value.accept(p)}")
+            processed_value = value.accept(p) or "..."  # at least, don't crash
+            base_types.append(f"{name}={processed_value}")
         return base_types
 
     def get_class_decorators(self, cdef: ClassDef) -> list[str]:
@@ -1847,6 +1873,9 @@ def parse_options(args: list[str]) -> Options:
         dest="files",
         help="generate stubs for given files or directories",
     )
+    parser.add_argument(
+        "--version", action="version", version="%(prog)s " + mypy.version.__version__
+    )
 
     ns = parser.parse_args(args)
 

mypy/stubtest.py

@@ -1224,6 +1224,9 @@ def _verify_readonly_property(stub: nodes.Decorator, runtime: Any) -> Iterator[s
     if isinstance(runtime, property):
         yield from _verify_final_method(stub.func, runtime.fget, MISSING)
         return
+    if isinstance(runtime, functools.cached_property):
+        yield from _verify_final_method(stub.func, runtime.func, MISSING)
+        return
     if inspect.isdatadescriptor(runtime):
         # It's enough like a property...
         return