From 3010efc873f0dfd0eef2c971feee1f9cc2ce97d8 Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Mon, 24 Mar 2025 20:08:57 +0000
Subject: [PATCH 01/20] Consolidate descriptor handling in checkmember.py
 (#18831)

This is not a pure refactoring, but almost. Right now we are in a weird
situation where we have two inconsistencies:
* `__set__()` is handled in `checker.py` while `__get__()` is handled in
`checkmember.py`
* rules for when to use binder are slightly different between
descriptors and settable properties.

This PR fixes these two things. As a nice bonus we should get free
support for unions in `__set__()`.
---
 mypy/checker.py     |  24 ++++++---
 mypy/checkexpr.py   |  10 +++-
 mypy/checkmember.py | 126 ++++++++++++++++++++++++++++++++++++++------
 3 files changed, 133 insertions(+), 27 deletions(-)

diff --git a/mypy/checker.py b/mypy/checker.py
index ac4b24709783..fb435870df8c 100644
--- a/mypy/checker.py
+++ b/mypy/checker.py
@@ -3170,7 +3170,7 @@ def check_assignment(
             )
         else:
             self.try_infer_partial_generic_type_from_assignment(lvalue, rvalue, "=")
-            lvalue_type, index_lvalue, inferred = self.check_lvalue(lvalue)
+            lvalue_type, index_lvalue, inferred = self.check_lvalue(lvalue, rvalue)
             # If we're assigning to __getattr__ or similar methods, check that the signature is
             # valid.
             if isinstance(lvalue, NameExpr) and lvalue.node:
@@ -4263,7 +4263,9 @@ def check_multi_assignment_from_iterable(
         else:
             self.msg.type_not_iterable(rvalue_type, context)
 
-    def check_lvalue(self, lvalue: Lvalue) -> tuple[Type | None, IndexExpr | None, Var | None]:
+    def check_lvalue(
+        self, lvalue: Lvalue, rvalue: Expression | None = None
+    ) -> tuple[Type | None, IndexExpr | None, Var | None]:
         lvalue_type = None
         index_lvalue = None
         inferred = None
@@ -4281,7 +4283,7 @@ def check_lvalue(self, lvalue: Lvalue) -> tuple[Type | None, IndexExpr | None, V
         elif isinstance(lvalue, IndexExpr):
             index_lvalue = lvalue
         elif isinstance(lvalue, MemberExpr):
-            lvalue_type = self.expr_checker.analyze_ordinary_member_access(lvalue, True)
+            lvalue_type = self.expr_checker.analyze_ordinary_member_access(lvalue, True, rvalue)
             self.store_type(lvalue, lvalue_type)
         elif isinstance(lvalue, NameExpr):
             lvalue_type = self.expr_checker.analyze_ref_expr(lvalue, lvalue=True)
@@ -4552,12 +4554,8 @@ def check_member_assignment(
 
         Return the inferred rvalue_type, inferred lvalue_type, and whether to use the binder
         for this assignment.
-
-        Note: this method exists here and not in checkmember.py, because we need to take
-        care about interaction between binder and __set__().
         """
         instance_type = get_proper_type(instance_type)
-        attribute_type = get_proper_type(attribute_type)
         # Descriptors don't participate in class-attribute access
         if (isinstance(instance_type, FunctionLike) and instance_type.is_type_obj()) or isinstance(
             instance_type, TypeType
@@ -4569,8 +4567,8 @@ def check_member_assignment(
             get_lvalue_type = self.expr_checker.analyze_ordinary_member_access(
                 lvalue, is_lvalue=False
             )
-            use_binder = is_same_type(get_lvalue_type, attribute_type)
 
+<<<<<<< HEAD
         if not isinstance(attribute_type, Instance):
             # TODO: support __set__() for union types.
             rvalue_type = self.check_simple_assignment(attribute_type, rvalue, context)
@@ -4664,13 +4662,23 @@ def check_member_assignment(
             return AnyType(TypeOfAny.from_error), get_type, False
 
         set_type = inferred_dunder_set_type.arg_types[1]
+=======
+>>>>>>> df9ddfcac (Consolidate descriptor handling in checkmember.py (#18831))
         # Special case: if the rvalue_type is a subtype of both '__get__' and '__set__' types,
         # and '__get__' type is narrower than '__set__', then we invoke the binder to narrow type
         # by this assignment. Technically, this is not safe, but in practice this is
         # what a user expects.
+<<<<<<< HEAD
         rvalue_type = self.check_simple_assignment(set_type, rvalue, context)
         infer = is_subtype(rvalue_type, get_type) and is_subtype(get_type, set_type)
         return rvalue_type if infer else set_type, get_type, infer
+=======
+        rvalue_type, _ = self.check_simple_assignment(attribute_type, rvalue, context)
+        infer = is_subtype(rvalue_type, get_lvalue_type) and is_subtype(
+            get_lvalue_type, attribute_type
+        )
+        return rvalue_type if infer else attribute_type, attribute_type, infer
+>>>>>>> df9ddfcac (Consolidate descriptor handling in checkmember.py (#18831))
 
     def check_indexed_assignment(
         self, lvalue: IndexExpr, rvalue: Expression, context: Context
diff --git a/mypy/checkexpr.py b/mypy/checkexpr.py
index 1017009ce7ab..3fa4df2a7171 100644
--- a/mypy/checkexpr.py
+++ b/mypy/checkexpr.py
@@ -3327,8 +3327,13 @@ def visit_member_expr(self, e: MemberExpr, is_lvalue: bool = False) -> Type:
         self.chk.warn_deprecated(e.node, e)
         return narrowed
 
-    def analyze_ordinary_member_access(self, e: MemberExpr, is_lvalue: bool) -> Type:
-        """Analyse member expression or member lvalue."""
+    def analyze_ordinary_member_access(
+        self, e: MemberExpr, is_lvalue: bool, rvalue: Expression | None = None
+    ) -> Type:
+        """Analyse member expression or member lvalue.
+
+        An rvalue can be provided optionally to infer better setter type when is_lvalue is True.
+        """
         if e.kind is not None:
             # This is a reference to a module attribute.
             return self.analyze_ref_expr(e)
@@ -3360,6 +3365,7 @@ def analyze_ordinary_member_access(self, e: MemberExpr, is_lvalue: bool) -> Type
                 in_literal_context=self.is_literal_context(),
                 module_symbol_table=module_symbol_table,
                 is_self=is_self,
+                rvalue=rvalue,
             )
 
             return member_type
diff --git a/mypy/checkmember.py b/mypy/checkmember.py
index 0994d0df400b..9b7c8027e1ed 100644
--- a/mypy/checkmember.py
+++ b/mypy/checkmember.py
@@ -23,6 +23,7 @@
     ArgKind,
     Context,
     Decorator,
+    Expression,
     FuncBase,
     FuncDef,
     IndexExpr,
@@ -101,6 +102,7 @@ def __init__(
         module_symbol_table: SymbolTable | None = None,
         no_deferral: bool = False,
         is_self: bool = False,
+        rvalue: Expression | None = None,
     ) -> None:
         self.is_lvalue = is_lvalue
         self.is_super = is_super
@@ -113,6 +115,9 @@ def __init__(
         self.module_symbol_table = module_symbol_table
         self.no_deferral = no_deferral
         self.is_self = is_self
+        if rvalue is not None:
+            assert is_lvalue
+        self.rvalue = rvalue
 
     def named_type(self, name: str) -> Instance:
         return self.chk.named_type(name)
@@ -139,6 +144,7 @@ def copy_modified(
             self_type=self.self_type,
             module_symbol_table=self.module_symbol_table,
             no_deferral=self.no_deferral,
+            rvalue=self.rvalue,
         )
         if messages is not None:
             mx.msg = messages
@@ -168,6 +174,7 @@ def analyze_member_access(
     module_symbol_table: SymbolTable | None = None,
     no_deferral: bool = False,
     is_self: bool = False,
+    rvalue: Expression | None = None,
 ) -> Type:
     """Return the type of attribute 'name' of 'typ'.
 
@@ -186,11 +193,14 @@ def analyze_member_access(
     of 'original_type'. 'original_type' is always preserved as the 'typ' type used in
     the initial, non-recursive call. The 'self_type' is a component of 'original_type'
     to which generic self should be bound (a narrower type that has a fallback to instance).
-    Currently this is used only for union types.
+    Currently, this is used only for union types.
 
-    'module_symbol_table' is passed to this function if 'typ' is actually a module
+    'module_symbol_table' is passed to this function if 'typ' is actually a module,
     and we want to keep track of the available attributes of the module (since they
     are not available via the type object directly)
+
+    'rvalue' can be provided optionally to infer better setter type when is_lvalue is True,
+    most notably this helps for descriptors with overloaded __set__() method.
     """
     mx = MemberContext(
         is_lvalue=is_lvalue,
@@ -204,6 +214,7 @@ def analyze_member_access(
         module_symbol_table=module_symbol_table,
         no_deferral=no_deferral,
         is_self=is_self,
+        rvalue=rvalue,
     )
     result = _analyze_member_access(name, typ, mx, override_info)
     possible_literal = get_proper_type(result)
@@ -629,9 +640,7 @@ def check_final_member(name: str, info: TypeInfo, msg: MessageBuilder, ctx: Cont
             msg.cant_assign_to_final(name, attr_assign=True, ctx=ctx)
 
 
-def analyze_descriptor_access(
-    descriptor_type: Type, mx: MemberContext, *, assignment: bool = False
-) -> Type:
+def analyze_descriptor_access(descriptor_type: Type, mx: MemberContext) -> Type:
     """Type check descriptor access.
 
     Arguments:
@@ -639,7 +648,7 @@ def analyze_descriptor_access(
             (the type of ``f`` in ``a.f`` when ``f`` is a descriptor).
         mx: The current member access context.
     Return:
-        The return type of the appropriate ``__get__`` overload for the descriptor.
+        The return type of the appropriate ``__get__/__set__`` overload for the descriptor.
     """
     instance_type = get_proper_type(mx.self_type)
     orig_descriptor_type = descriptor_type
@@ -648,15 +657,24 @@ def analyze_descriptor_access(
     if isinstance(descriptor_type, UnionType):
         # Map the access over union types
         return make_simplified_union(
-            [
-                analyze_descriptor_access(typ, mx, assignment=assignment)
-                for typ in descriptor_type.items
-            ]
+            [analyze_descriptor_access(typ, mx) for typ in descriptor_type.items]
         )
     elif not isinstance(descriptor_type, Instance):
         return orig_descriptor_type
 
-    if not descriptor_type.type.has_readable_member("__get__"):
+    if not mx.is_lvalue and not descriptor_type.type.has_readable_member("__get__"):
+        return orig_descriptor_type
+
+    # We do this check first to accommodate for descriptors with only __set__ method.
+    # If there is no __set__, we type-check that the assigned value matches
+    # the return type of __get__. This doesn't match the python semantics,
+    # (which allow you to override the descriptor with any value), but preserves
+    # the type of accessing the attribute (even after the override).
+    if mx.is_lvalue and descriptor_type.type.has_readable_member("__set__"):
+        return analyze_descriptor_assign(descriptor_type, mx)
+
+    if mx.is_lvalue and not descriptor_type.type.has_readable_member("__get__"):
+        # This turned out to be not a descriptor after all.
         return orig_descriptor_type
 
     dunder_get = descriptor_type.type.get_method("__get__")
@@ -713,11 +731,10 @@ def analyze_descriptor_access(
         callable_name=callable_name,
     )
 
-    if not assignment:
-        mx.chk.check_deprecated(dunder_get, mx.context)
-        mx.chk.warn_deprecated_overload_item(
-            dunder_get, mx.context, target=inferred_dunder_get_type, selftype=descriptor_type
-        )
+    mx.chk.check_deprecated(dunder_get, mx.context)
+    mx.chk.warn_deprecated_overload_item(
+        dunder_get, mx.context, target=inferred_dunder_get_type, selftype=descriptor_type
+    )
 
     inferred_dunder_get_type = get_proper_type(inferred_dunder_get_type)
     if isinstance(inferred_dunder_get_type, AnyType):
@@ -736,6 +753,79 @@ def analyze_descriptor_access(
     return inferred_dunder_get_type.ret_type
 
 
+def analyze_descriptor_assign(descriptor_type: Instance, mx: MemberContext) -> Type:
+    instance_type = get_proper_type(mx.self_type)
+    dunder_set = descriptor_type.type.get_method("__set__")
+    if dunder_set is None:
+        mx.chk.fail(
+            message_registry.DESCRIPTOR_SET_NOT_CALLABLE.format(
+                descriptor_type.str_with_options(mx.msg.options)
+            ),
+            mx.context,
+        )
+        return AnyType(TypeOfAny.from_error)
+
+    bound_method = analyze_decorator_or_funcbase_access(
+        defn=dunder_set,
+        itype=descriptor_type,
+        name="__set__",
+        mx=mx.copy_modified(is_lvalue=False, self_type=descriptor_type),
+    )
+    typ = map_instance_to_supertype(descriptor_type, dunder_set.info)
+    dunder_set_type = expand_type_by_instance(bound_method, typ)
+
+    callable_name = mx.chk.expr_checker.method_fullname(descriptor_type, "__set__")
+    rvalue = mx.rvalue or TempNode(AnyType(TypeOfAny.special_form), context=mx.context)
+    dunder_set_type = mx.chk.expr_checker.transform_callee_type(
+        callable_name,
+        dunder_set_type,
+        [TempNode(instance_type, context=mx.context), rvalue],
+        [ARG_POS, ARG_POS],
+        mx.context,
+        object_type=descriptor_type,
+    )
+
+    # For non-overloaded setters, the result should be type-checked like a regular assignment.
+    # Hence, we first only try to infer the type by using the rvalue as type context.
+    type_context = rvalue
+    with mx.msg.filter_errors():
+        _, inferred_dunder_set_type = mx.chk.expr_checker.check_call(
+            dunder_set_type,
+            [TempNode(instance_type, context=mx.context), type_context],
+            [ARG_POS, ARG_POS],
+            mx.context,
+            object_type=descriptor_type,
+            callable_name=callable_name,
+        )
+
+    # And now we in fact type check the call, to show errors related to wrong arguments
+    # count, etc., replacing the type context for non-overloaded setters only.
+    inferred_dunder_set_type = get_proper_type(inferred_dunder_set_type)
+    if isinstance(inferred_dunder_set_type, CallableType):
+        type_context = TempNode(AnyType(TypeOfAny.special_form), context=mx.context)
+    mx.chk.expr_checker.check_call(
+        dunder_set_type,
+        [TempNode(instance_type, context=mx.context), type_context],
+        [ARG_POS, ARG_POS],
+        mx.context,
+        object_type=descriptor_type,
+        callable_name=callable_name,
+    )
+
+    # Search for possible deprecations:
+    mx.chk.check_deprecated(dunder_set, mx.context)
+    mx.chk.warn_deprecated_overload_item(
+        dunder_set, mx.context, target=inferred_dunder_set_type, selftype=descriptor_type
+    )
+
+    # In the following cases, a message already will have been recorded in check_call.
+    if (not isinstance(inferred_dunder_set_type, CallableType)) or (
+        len(inferred_dunder_set_type.arg_types) < 2
+    ):
+        return AnyType(TypeOfAny.from_error)
+    return inferred_dunder_set_type.arg_types[1]
+
+
 def is_instance_var(var: Var) -> bool:
     """Return if var is an instance variable according to PEP 526."""
     return (
@@ -820,6 +910,7 @@ def analyze_var(
                     # A property cannot have an overloaded type => the cast is fine.
                     assert isinstance(expanded_signature, CallableType)
                     if var.is_settable_property and mx.is_lvalue and var.setter_type is not None:
+                        # TODO: use check_call() to infer better type, same as for __set__().
                         result = expanded_signature.arg_types[0]
                     else:
                         result = expanded_signature.ret_type
@@ -832,7 +923,7 @@ def analyze_var(
         result = AnyType(TypeOfAny.special_form)
     fullname = f"{var.info.fullname}.{name}"
     hook = mx.chk.plugin.get_attribute_hook(fullname)
-    if result and not mx.is_lvalue and not implicit:
+    if result and not (implicit or var.info.is_protocol and is_instance_var(var)):
         result = analyze_descriptor_access(result, mx)
     if hook:
         result = hook(
@@ -1106,6 +1197,7 @@ def analyze_class_attribute_access(
         result = add_class_tvars(
             t, isuper, is_classmethod, is_staticmethod, mx.self_type, original_vars=original_vars
         )
+        # __set__ is not called on class objects.
         if not mx.is_lvalue:
             result = analyze_descriptor_access(result, mx)
 

From 8e7c094a409f766395f2c4c31e0edbf99614df31 Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Wed, 30 Apr 2025 10:20:34 +0100
Subject: [PATCH 02/20] Local forward refs should precede global forward refs
 (#19000)

Fixes https://github.com/python/mypy/issues/18988

This should be a minimal change to restore backwards compatibility for
an edge case with forward references.
---
 mypy/semanal.py                     |  9 ++++++++
 test-data/unit/check-python312.test | 36 ++++++++++++++++++++++++++---
 2 files changed, 42 insertions(+), 3 deletions(-)

diff --git a/mypy/semanal.py b/mypy/semanal.py
index a0cfdcce1e33..a3e113252ac3 100644
--- a/mypy/semanal.py
+++ b/mypy/semanal.py
@@ -6336,6 +6336,8 @@ class C:
             if node.name not in self.globals:
                 return True
             global_node = self.globals[node.name]
+            if not self.is_textually_before_class(global_node.node):
+                return True
             return not self.is_type_like(global_node.node)
         return False
 
@@ -6363,6 +6365,13 @@ def is_textually_before_statement(self, node: SymbolNode) -> bool:
         else:
             return line_diff > 0
 
+    def is_textually_before_class(self, node: SymbolNode | None) -> bool:
+        """Similar to above, but check if a node is defined before current class."""
+        assert self.type is not None
+        if node is None:
+            return False
+        return node.line < self.type.defn.line
+
     def is_overloaded_item(self, node: SymbolNode, statement: Statement) -> bool:
         """Check whether the function belongs to the overloaded variants"""
         if isinstance(node, OverloadedFuncDef) and isinstance(statement, FuncDef):
diff --git a/test-data/unit/check-python312.test b/test-data/unit/check-python312.test
index ba4104a50048..2244548ea969 100644
--- a/test-data/unit/check-python312.test
+++ b/test-data/unit/check-python312.test
@@ -2004,15 +2004,18 @@ reveal_type(x.related_resources)  # N: Revealed type is "__main__.ResourceRule"
 
 [case testPEP695TypeAliasRecursiveOuterClass]
 class A:
-    type X = X
+    type X = X  # E: Cannot resolve name "X" (possible cyclic definition)
 class X: ...
 
+class AA:
+    XX = XX  # OK, we allow this as a special case.
+class XX: ...
+
 class Y: ...
 class B:
     type Y = Y
 
-x: A.X
-reveal_type(x)  # N: Revealed type is "__main__.X"
+reveal_type(AA.XX)  # N: Revealed type is "def () -> __main__.XX"
 y: B.Y
 reveal_type(y)  # N: Revealed type is "__main__.Y"
 [builtins fixtures/tuple.pyi]
@@ -2029,3 +2032,30 @@ def foo() -> None:
 class Z: ...  # E: Name "Z" already defined on line 2
 [builtins fixtures/tuple.pyi]
 [typing fixtures/typing-full.pyi]
+
+[case testPEP695MultipleUnpacksInBareApplicationNoCrash]
+# https://github.com/python/mypy/issues/18856
+class A[*Ts]: ...
+
+A[*tuple[int, ...], *tuple[int, ...]]  # E: More than one Unpack in a type is not allowed
+a: A[*tuple[int, ...], *tuple[int, ...]]  # E: More than one Unpack in a type is not allowed
+def foo(a: A[*tuple[int, ...], *tuple[int, ...]]): ...  # E: More than one Unpack in a type is not allowed
+
+tuple[*tuple[int, ...], *tuple[int, ...]]  # E: More than one Unpack in a type is not allowed
+b: tuple[*tuple[int, ...], *tuple[int, ...]]  # E: More than one Unpack in a type is not allowed
+[builtins fixtures/tuple.pyi]
+[typing fixtures/typing-full.pyi]
+
+[case testForwardNestedPrecedesForwardGlobal]
+from typing import NewType
+
+class W[T]: pass
+
+class R:
+    class M(W[Action.V], type):
+        FOO = R.Action.V(0)
+    class Action(metaclass=M):
+        V = NewType('V', int)
+
+class Action:
+    pass

From ea8aacd27d8d7252ee88b5715889be03e0e88c3f Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Wed, 30 Apr 2025 16:35:27 +0100
Subject: [PATCH 03/20] Do not narrow types to Never with binder (#18972)

Fixes https://github.com/python/mypy/issues/18967
Fixes https://github.com/python/mypy/issues/16494
Fixes https://github.com/python/mypy/issues/15793
Fixes https://github.com/python/mypy/issues/12949

As you can see from updated test cases, it is kind of gray area, so
whether we go this way will depend on the `mypy_primer` results (and
also potentially on Dropbox internal code bases, where the above issue
may cause problems).
---
 mypy/checkexpr.py                    |  8 +++++++-
 test-data/unit/check-isinstance.test |  4 ++--
 test-data/unit/check-narrowing.test  | 13 ++++++++++++-
 test-data/unit/check-python310.test  |  2 +-
 4 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/mypy/checkexpr.py b/mypy/checkexpr.py
index 3fa4df2a7171..008e056f4367 100644
--- a/mypy/checkexpr.py
+++ b/mypy/checkexpr.py
@@ -6277,7 +6277,13 @@ def narrow_type_from_binder(
                     known_type, restriction, prohibit_none_typevar_overlap=True
                 ):
                     return None
-                return narrow_declared_type(known_type, restriction)
+                narrowed = narrow_declared_type(known_type, restriction)
+                if isinstance(get_proper_type(narrowed), UninhabitedType):
+                    # If we hit this case, it means that we can't reliably mark the code as
+                    # unreachable, but the resulting type can't be expressed in type system.
+                    # Falling back to restriction is more intuitive in most cases.
+                    return restriction
+                return narrowed
         return known_type
 
     def has_abstract_type_part(self, caller_type: ProperType, callee_type: ProperType) -> bool:
diff --git a/test-data/unit/check-isinstance.test b/test-data/unit/check-isinstance.test
index 49140bf52b8d..058db1ea8197 100644
--- a/test-data/unit/check-isinstance.test
+++ b/test-data/unit/check-isinstance.test
@@ -1812,9 +1812,9 @@ reveal_type(fm)  # N: Revealed type is "__main__.FooMetaclass"
 if issubclass(fm, Foo):
     reveal_type(fm)  # N: Revealed type is "Type[__main__.Foo]"
 if issubclass(fm, Bar):
-    reveal_type(fm)  # N: Revealed type is "Never"
+    reveal_type(fm)  # N: Revealed type is "Type[__main__.Bar]"
 if issubclass(fm, Baz):
-    reveal_type(fm)  # N: Revealed type is "Never"
+    reveal_type(fm)  # N: Revealed type is "Type[__main__.Baz]"
 [builtins fixtures/isinstance.pyi]
 
 [case testIsinstanceAndNarrowTypeVariable]
diff --git a/test-data/unit/check-narrowing.test b/test-data/unit/check-narrowing.test
index 1856ca26f736..dc2cfd46d9ad 100644
--- a/test-data/unit/check-narrowing.test
+++ b/test-data/unit/check-narrowing.test
@@ -1284,7 +1284,7 @@ def f(t: Type[T], a: A, b: B) -> None:
         reveal_type(a)  # N: Revealed type is "__main__.A"
 
     if type(b) is t:
-        reveal_type(b)  # N: Revealed type is "Never"
+        reveal_type(b)  # N: Revealed type is "T`-1"
     else:
         reveal_type(b)  # N: Revealed type is "__main__.B"
 
@@ -2413,3 +2413,14 @@ def foo(x: T) -> T:
     reveal_type(x)  # N: Revealed type is "T`-1"
     return x
 [builtins fixtures/isinstance.pyi]
+
+[case testDoNotNarrowToNever]
+def any():
+    return 1
+
+def f() -> None:
+    x = "a"
+    x = any()
+    assert isinstance(x, int)
+    reveal_type(x)  # N: Revealed type is "builtins.int"
+[builtins fixtures/isinstance.pyi]
diff --git a/test-data/unit/check-python310.test b/test-data/unit/check-python310.test
index 016f50552a5f..a25a7b7107c7 100644
--- a/test-data/unit/check-python310.test
+++ b/test-data/unit/check-python310.test
@@ -1299,7 +1299,7 @@ m: str
 
 match m:
     case a if a := 1:  # E: Incompatible types in assignment (expression has type "int", variable has type "str")
-        reveal_type(a)  # N: Revealed type is "Never"
+        reveal_type(a)  # N: Revealed type is "Literal[1]?"
 
 [case testMatchAssigningPatternGuard]
 m: str

From 0cd434f821eb951283e400a6b93592b1b61daa0f Mon Sep 17 00:00:00 2001
From: Jared Hance <jhance@dropbox.com>
Date: Fri, 9 May 2025 17:50:49 -0700
Subject: [PATCH 04/20] fix

---
 mypy/checker.py | 104 +-----------------------------------------------
 1 file changed, 1 insertion(+), 103 deletions(-)

diff --git a/mypy/checker.py b/mypy/checker.py
index fb435870df8c..c899acfe7cba 100644
--- a/mypy/checker.py
+++ b/mypy/checker.py
@@ -4568,117 +4568,15 @@ def check_member_assignment(
                 lvalue, is_lvalue=False
             )
 
-<<<<<<< HEAD
-        if not isinstance(attribute_type, Instance):
-            # TODO: support __set__() for union types.
-            rvalue_type = self.check_simple_assignment(attribute_type, rvalue, context)
-            return rvalue_type, attribute_type, use_binder
-
-        mx = MemberContext(
-            is_lvalue=False,
-            is_super=False,
-            is_operator=False,
-            original_type=instance_type,
-            context=context,
-            self_type=None,
-            msg=self.msg,
-            chk=self,
-        )
-        get_type = analyze_descriptor_access(attribute_type, mx, assignment=True)
-        if not attribute_type.type.has_readable_member("__set__"):
-            # If there is no __set__, we type-check that the assigned value matches
-            # the return type of __get__. This doesn't match the python semantics,
-            # (which allow you to override the descriptor with any value), but preserves
-            # the type of accessing the attribute (even after the override).
-            rvalue_type = self.check_simple_assignment(get_type, rvalue, context)
-            return rvalue_type, get_type, use_binder
-
-        dunder_set = attribute_type.type.get_method("__set__")
-        if dunder_set is None:
-            self.fail(
-                message_registry.DESCRIPTOR_SET_NOT_CALLABLE.format(
-                    attribute_type.str_with_options(self.options)
-                ),
-                context,
-            )
-            return AnyType(TypeOfAny.from_error), get_type, False
-
-        bound_method = analyze_decorator_or_funcbase_access(
-            defn=dunder_set,
-            itype=attribute_type,
-            name="__set__",
-            mx=mx.copy_modified(self_type=attribute_type),
-        )
-        typ = map_instance_to_supertype(attribute_type, dunder_set.info)
-        dunder_set_type = expand_type_by_instance(bound_method, typ)
-
-        callable_name = self.expr_checker.method_fullname(attribute_type, "__set__")
-        dunder_set_type = self.expr_checker.transform_callee_type(
-            callable_name,
-            dunder_set_type,
-            [TempNode(instance_type, context=context), rvalue],
-            [nodes.ARG_POS, nodes.ARG_POS],
-            context,
-            object_type=attribute_type,
-        )
-
-        # For non-overloaded setters, the result should be type-checked like a regular assignment.
-        # Hence, we first only try to infer the type by using the rvalue as type context.
-        type_context = rvalue
-        with self.msg.filter_errors():
-            _, inferred_dunder_set_type = self.expr_checker.check_call(
-                dunder_set_type,
-                [TempNode(instance_type, context=context), type_context],
-                [nodes.ARG_POS, nodes.ARG_POS],
-                context,
-                object_type=attribute_type,
-                callable_name=callable_name,
-            )
-
-        # And now we in fact type check the call, to show errors related to wrong arguments
-        # count, etc., replacing the type context for non-overloaded setters only.
-        inferred_dunder_set_type = get_proper_type(inferred_dunder_set_type)
-        if isinstance(inferred_dunder_set_type, CallableType):
-            type_context = TempNode(AnyType(TypeOfAny.special_form), context=context)
-        self.expr_checker.check_call(
-            dunder_set_type,
-            [TempNode(instance_type, context=context), type_context],
-            [nodes.ARG_POS, nodes.ARG_POS],
-            context,
-            object_type=attribute_type,
-            callable_name=callable_name,
-        )
-
-        # Search for possible deprecations:
-        mx.chk.check_deprecated(dunder_set, mx.context)
-        mx.chk.warn_deprecated_overload_item(
-            dunder_set, mx.context, target=inferred_dunder_set_type, selftype=attribute_type
-        )
-
-        # In the following cases, a message already will have been recorded in check_call.
-        if (not isinstance(inferred_dunder_set_type, CallableType)) or (
-            len(inferred_dunder_set_type.arg_types) < 2
-        ):
-            return AnyType(TypeOfAny.from_error), get_type, False
-
-        set_type = inferred_dunder_set_type.arg_types[1]
-=======
->>>>>>> df9ddfcac (Consolidate descriptor handling in checkmember.py (#18831))
         # Special case: if the rvalue_type is a subtype of both '__get__' and '__set__' types,
         # and '__get__' type is narrower than '__set__', then we invoke the binder to narrow type
         # by this assignment. Technically, this is not safe, but in practice this is
         # what a user expects.
-<<<<<<< HEAD
-        rvalue_type = self.check_simple_assignment(set_type, rvalue, context)
-        infer = is_subtype(rvalue_type, get_type) and is_subtype(get_type, set_type)
-        return rvalue_type if infer else set_type, get_type, infer
-=======
-        rvalue_type, _ = self.check_simple_assignment(attribute_type, rvalue, context)
+        rvalue_type = self.check_simple_assignment(attribute_type, rvalue, context)
         infer = is_subtype(rvalue_type, get_lvalue_type) and is_subtype(
             get_lvalue_type, attribute_type
         )
         return rvalue_type if infer else attribute_type, attribute_type, infer
->>>>>>> df9ddfcac (Consolidate descriptor handling in checkmember.py (#18831))
 
     def check_indexed_assignment(
         self, lvalue: IndexExpr, rvalue: Expression, context: Context

From 8ed26e5eebb214f46b739b3f4bbd1ac6894450de Mon Sep 17 00:00:00 2001
From: Stanislav Terliakov <50529348+sterliakov@users.noreply.github.com>
Date: Mon, 31 Mar 2025 02:29:50 +0200
Subject: [PATCH 05/20] Fix crash on multiple unpacks in a bare type
 application (#18857)

Fixes #18856. This should be done by `TypeAnalyzer.anal_array` but is
not - semanal only invokes its own wrapper around `anal_type`

---------

Co-authored-by: Ivan Levkivskyi <levkivskyi@gmail.com>
---
 mypy/semanal.py  | 2 ++
 mypy/typeanal.py | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/mypy/semanal.py b/mypy/semanal.py
index a3e113252ac3..66ef9f0abeef 100644
--- a/mypy/semanal.py
+++ b/mypy/semanal.py
@@ -6041,6 +6041,8 @@ def analyze_type_application_args(self, expr: IndexExpr) -> list[Type] | None:
                 return None
             types.append(analyzed)
 
+        if allow_unpack:
+            types = self.type_analyzer().check_unpacks_in_list(types)
         if has_param_spec and num_args == 1 and types:
             first_arg = get_proper_type(types[0])
             single_any = len(types) == 1 and isinstance(first_arg, AnyType)
diff --git a/mypy/typeanal.py b/mypy/typeanal.py
index 9208630937e7..7bf21709b863 100644
--- a/mypy/typeanal.py
+++ b/mypy/typeanal.py
@@ -2006,7 +2006,7 @@ def check_unpacks_in_list(self, items: list[Type]) -> list[Type]:
 
         if num_unpacks > 1:
             assert final_unpack is not None
-            self.fail("More than one Unpack in a type is not allowed", final_unpack)
+            self.fail("More than one Unpack in a type is not allowed", final_unpack.type)
         return new_items
 
     def tuple_type(self, items: list[Type], line: int, column: int) -> TupleType:

From a499d9fdba06732248c07586f2fd95c47a4fa0f7 Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Tue, 27 May 2025 16:10:06 +0100
Subject: [PATCH 06/20] Document --allow-redefinition-new (#19153)

The feature was introduced in #18727.
---
 docs/source/command_line.rst | 50 ++++++++++++++++++++++++++++++++++--
 docs/source/config_file.rst  | 39 ++++++++++++++++++++++++++++
 2 files changed, 87 insertions(+), 2 deletions(-)

diff --git a/docs/source/command_line.rst b/docs/source/command_line.rst
index b455e287017e..dfed280d12ed 100644
--- a/docs/source/command_line.rst
+++ b/docs/source/command_line.rst
@@ -593,12 +593,58 @@ of the above sections.
     This flag causes mypy to suppress errors caused by not being able to fully
     infer the types of global and class variables.
 
-.. option:: --allow-redefinition
+.. option:: --allow-redefinition-new
 
     By default, mypy won't allow a variable to be redefined with an
-    unrelated type. This flag enables redefinition of a variable with an
+    unrelated type. This *experimental* flag enables the redefinition of
+    unannotated variables with an arbitrary type. You will also need to enable
+    :option:`--local-partial-types <mypy --local-partial-types>`.
+    Example:
+
+    .. code-block:: python
+
+        def maybe_convert(n: int, b: bool) -> int | str:
+            if b:
+                x = str(n)  # Assign "str"
+            else:
+                x = n       # Assign "int"
+            # Type of "x" is "int | str" here.
+            return x
+
+    Without the new flag, mypy only supports inferring optional types
+    (``X | None``) from multiple assignments. With this option enabled,
+    mypy can infer arbitrary union types.
+
+    This also enables an unannotated variable to have different types in different
+    code locations:
+
+    .. code-block:: python
+
+        if check():
+            for x in range(n):
+                # Type of "x" is "int" here.
+                ...
+        else:
+            for x in ['a', 'b']:
+                # Type of "x" is "str" here.
+                ...
+
+    Note: We are planning to turn this flag on by default in a future mypy
+    release, along with :option:`--local-partial-types <mypy --local-partial-types>`.
+    The feature is still experimental, and the semantics may still change.
+
+.. option:: --allow-redefinition
+
+    This is an older variant of
+    :option:`--allow-redefinition-new <mypy --allow-redefinition-new>`.
+    This flag enables redefinition of a variable with an
     arbitrary type *in some contexts*: only redefinitions within the
     same block and nesting depth as the original definition are allowed.
+
+    We have no plans to remove this flag, but we expect that
+    :option:`--allow-redefinition-new <mypy --allow-redefinition-new>`
+    will replace this flag for new use cases eventually.
+
     Example where this can be useful:
 
     .. code-block:: python
diff --git a/docs/source/config_file.rst b/docs/source/config_file.rst
index de51f0c796fd..9f23617b9481 100644
--- a/docs/source/config_file.rst
+++ b/docs/source/config_file.rst
@@ -713,6 +713,44 @@ section of the command line docs.
     Causes mypy to suppress errors caused by not being able to fully
     infer the types of global and class variables.
 
+.. confval:: allow_redefinition_new
+
+    :type: boolean
+    :default: False
+
+    By default, mypy won't allow a variable to be redefined with an
+    unrelated type. This *experimental* flag enables the redefinition of
+    unannotated variables with an arbitrary type. You will also need to enable
+    :confval:`local_partial_types`.
+    Example:
+
+    .. code-block:: python
+
+        def maybe_convert(n: int, b: bool) -> int | str:
+            if b:
+                x = str(n)  # Assign "str"
+            else:
+                x = n       # Assign "int"
+            # Type of "x" is "int | str" here.
+            return x
+
+    This also enables an unannotated variable to have different types in different
+    code locations:
+
+    .. code-block:: python
+
+        if check():
+            for x in range(n):
+                # Type of "x" is "int" here.
+                ...
+        else:
+            for x in ['a', 'b']:
+                # Type of "x" is "str" here.
+                ...
+
+    Note: We are planning to turn this flag on by default in a future mypy
+    release, along with :confval:`local_partial_types`.
+
 .. confval:: allow_redefinition
 
     :type: boolean
@@ -746,6 +784,7 @@ section of the command line docs.
 
     Disallows inferring variable type for ``None`` from two assignments in different scopes.
     This is always implicitly enabled when using the :ref:`mypy daemon <mypy_daemon>`.
+    This will be enabled by default in a future mypy release.
 
 .. confval:: disable_error_code
 

From 334469f999c5c777124a123062b4349614447e0d Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Tue, 27 May 2025 16:59:29 +0100
Subject: [PATCH 07/20] [mypyc] Improve documentation of native and non-native
 classes (#19154)

Also discuss `mypyc_attr(native_class=<...>)`.
---
 mypyc/doc/native_classes.rst | 82 ++++++++++++++++++++++++++++++++----
 1 file changed, 74 insertions(+), 8 deletions(-)

diff --git a/mypyc/doc/native_classes.rst b/mypyc/doc/native_classes.rst
index 7f892de3e239..dbcf238b78d5 100644
--- a/mypyc/doc/native_classes.rst
+++ b/mypyc/doc/native_classes.rst
@@ -48,11 +48,13 @@ can be assigned to (similar to using ``__slots__``)::
 Inheritance
 -----------
 
-Only single inheritance is supported (except for :ref:`traits
-<trait-types>`). Most non-native classes can't be used as base
-classes.
+Only single inheritance is supported from native classes (except for
+:ref:`traits <trait-types>`). Most non-native extension classes can't
+be used as base classes, but regular Python classes can be used as
+base classes unless they use unsupported metaclasses (see below for
+more about this).
 
-These non-native classes can be used as base classes of native
+These non-native extension classes can be used as base classes of native
 classes:
 
 * ``object``
@@ -63,8 +65,6 @@ classes:
 * ``IndexError``
 * ``LookupError``
 * ``UserWarning``
-* ``typing.NamedTuple``
-* ``enum.Enum``
 
 By default, a non-native class can't inherit a native class, and you
 can't inherit from a native class outside the compilation unit that
@@ -89,6 +89,15 @@ You need to install ``mypy-extensions`` to use ``@mypyc_attr``:
 
     pip install --upgrade mypy-extensions
 
+Additionally, mypyc recognizes these base classes as special, and
+understands how they alter the behavior of classes (including native
+classes) that subclass them:
+
+* ``typing.NamedTuple``
+* ``typing.Generic``
+* ``typing.Protocol``
+* ``enum.Enum``
+
 Class variables
 ---------------
 
@@ -145,7 +154,8 @@ behavior is too dynamic. You can use these metaclasses, however:
 .. note::
 
    If a class definition uses an unsupported metaclass, *mypyc
-   compiles the class into a regular Python class*.
+   compiles the class into a regular Python class* (non-native
+   class).
 
 Class decorators
 ----------------
@@ -165,7 +175,63 @@ efficient as pure native classes.
 .. note::
 
    If a class definition uses an unsupported class decorator, *mypyc
-   compiles the class into a regular Python class*.
+   compiles the class into a regular Python class* (non-native class).
+
+Defining non-native classes
+---------------------------
+
+You can use the ``@mypy_extensions.mypyc_attr(...)`` class decorator
+with an argument ``native_class=False`` to explicitly define normal
+Python classes (non-native classes)::
+
+    from mypy_extensions import mypyc_attr
+
+    @mypyc_attr(native_class=False)
+    class NonNative:
+        def __init__(self) -> None:
+            self.attr = 1
+
+    setattr(NonNative, "extra", 1)  # Ok
+
+This only has an effect in classes compiled using mypyc. Non-native
+classes are significantly less efficient than native classes, but they
+are sometimes necessary to work around the limitations of native classes.
+
+Non-native classes can use arbitrary metaclasses and class decorators,
+and they support flexible multiple inheritance.  Mypyc will still
+generate a compile-time error if you try to assign to a method, or an
+attribute that is not defined in a class body, since these are static
+type errors detected by mypy::
+
+    o = NonNative()
+    o.extra = "x"  # Static type error: "extra" not defined
+
+However, these operations still work at runtime, including in modules
+that are not compiled using mypyc. You can also use ``setattr`` and
+``getattr`` for dynamic access of arbitrary attributes. Expressions
+with an ``Any`` type are also not type checked statically, allowing
+access to arbitrary attributes::
+
+    a: Any = o
+    a.extra = "x"  # Ok
+
+    setattr(o, "extra", "y")  # Also ok
+
+Implicit non-native classes
+---------------------------
+
+If a compiled class uses an unsupported metaclass or an unsupported
+class decorator, it will implicitly be a non-native class, as
+discussed above. You can still use ``@mypyc_attr(native_class=False)``
+to explicitly mark it as a non-native class.
+
+Explicit native classes
+-----------------------
+
+You can use ``@mypyc_attr(native_class=True)`` to explicitly declare a
+class as a native class. It will be a compile-time error if mypyc
+can't compile the class as a native class. You can use this to avoid
+accidentally defining implicit non-native classes.
 
 Deleting attributes
 -------------------

From b6da4fcf97fca9cd28e81a880f818dc364b5a06d Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Wed, 28 May 2025 14:32:05 +0100
Subject: [PATCH 08/20] Allow enum members to have type objects as values
 (#19160)

Type objects as enum values are supported at runtime.

Fixes #19151.
---
 mypy/nodes.py                       |  4 ++--
 test-data/unit/check-python310.test | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/mypy/nodes.py b/mypy/nodes.py
index 584e56667944..2fb459142066 100644
--- a/mypy/nodes.py
+++ b/mypy/nodes.py
@@ -3313,8 +3313,8 @@ def enum_members(self) -> list[str]:
                         continue  # unannotated value not a member
 
                     typ = mypy.types.get_proper_type(sym.node.type)
-                    if isinstance(
-                        typ, mypy.types.FunctionLike
+                    if (
+                        isinstance(typ, mypy.types.FunctionLike) and not typ.is_type_obj()
                     ) or (  # explicit `@member` is required
                         isinstance(typ, mypy.types.Instance)
                         and typ.type.fullname == "enum.nonmember"
diff --git a/test-data/unit/check-python310.test b/test-data/unit/check-python310.test
index c2e2e5bddb34..af3982f6accd 100644
--- a/test-data/unit/check-python310.test
+++ b/test-data/unit/check-python310.test
@@ -2638,3 +2638,24 @@ def f2() -> None:
                 return
     reveal_type(y) # N: Revealed type is "builtins.str"
 [builtins fixtures/list.pyi]
+
+[case testEnumTypeObjectMember]
+import enum
+from typing import NoReturn
+
+def assert_never(x: NoReturn) -> None: ...
+
+class ValueType(enum.Enum):
+    INT = int
+    STR = str
+
+value_type: ValueType = ValueType.INT
+
+match value_type:
+    case ValueType.INT:
+        pass
+    case ValueType.STR:
+        pass
+    case _:
+        assert_never(value_type)
+[builtins fixtures/tuple.pyi]

From 2a036e739f8691576056669371d9f020e95c2603 Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Thu, 29 May 2025 10:40:42 +0100
Subject: [PATCH 09/20] Revert "Infer correct types with overloads of
 `Type[Guard | Is]`  (#19161)

This reverts commit 43ea203e566901510dbdd59e8907fcddb2a8ee70 (#17678).

The commit caused a regression (#19139). If we can't fix the regression
soon enough, reverting the original change temporarily will at least
unblock the mypy public release. The reverted PR can be merged again
once the regression is fixed.
---
 mypy/checker.py                     |  24 +-----
 mypy/checkexpr.py                   |  83 +++----------------
 test-data/unit/check-typeguard.test |  56 -------------
 test-data/unit/check-typeis.test    | 119 ----------------------------
 4 files changed, 14 insertions(+), 268 deletions(-)

diff --git a/mypy/checker.py b/mypy/checker.py
index aceb0291926a..9c389cccd95f 100644
--- a/mypy/checker.py
+++ b/mypy/checker.py
@@ -6160,31 +6160,15 @@ def find_isinstance_check_helper(
                         # considered "always right" (i.e. even if the types are not overlapping).
                         # Also note that a care must be taken to unwrap this back at read places
                         # where we use this to narrow down declared type.
-                        with self.msg.filter_errors(), self.local_type_map():
-                            # `node.callee` can be an `overload`ed function,
-                            # we need to resolve the real `overload` case.
-                            _, real_func = self.expr_checker.check_call(
-                                get_proper_type(self.lookup_type(node.callee)),
-                                node.args,
-                                node.arg_kinds,
-                                node,
-                                node.arg_names,
-                            )
-                        real_func = get_proper_type(real_func)
-                        if not isinstance(real_func, CallableType) or not (
-                            real_func.type_guard or real_func.type_is
-                        ):
-                            return {}, {}
-
-                        if real_func.type_guard is not None:
-                            return {expr: TypeGuardedType(real_func.type_guard)}, {}
+                        if node.callee.type_guard is not None:
+                            return {expr: TypeGuardedType(node.callee.type_guard)}, {}
                         else:
-                            assert real_func.type_is is not None
+                            assert node.callee.type_is is not None
                             return conditional_types_to_typemaps(
                                 expr,
                                 *self.conditional_types_with_intersection(
                                     self.lookup_type(expr),
-                                    [TypeRange(real_func.type_is, is_upper_bound=False)],
+                                    [TypeRange(node.callee.type_is, is_upper_bound=False)],
                                     expr,
                                 ),
                             )
diff --git a/mypy/checkexpr.py b/mypy/checkexpr.py
index ba2d38b6f528..f375c14c5fc4 100644
--- a/mypy/checkexpr.py
+++ b/mypy/checkexpr.py
@@ -2920,37 +2920,16 @@ def infer_overload_return_type(
             elif all_same_types([erase_type(typ) for typ in return_types]):
                 self.chk.store_types(type_maps[0])
                 return erase_type(return_types[0]), erase_type(inferred_types[0])
-            return self.check_call(
-                callee=AnyType(TypeOfAny.special_form),
-                args=args,
-                arg_kinds=arg_kinds,
-                arg_names=arg_names,
-                context=context,
-                callable_name=callable_name,
-                object_type=object_type,
-            )
-        elif not all_same_type_narrowers(matches):
-            # This is an example of how overloads can be:
-            #
-            # @overload
-            # def is_int(obj: float) -> TypeGuard[float]: ...
-            # @overload
-            # def is_int(obj: int) -> TypeGuard[int]: ...
-            #
-            # x: Any
-            # if is_int(x):
-            #     reveal_type(x)  # N: int | float
-            #
-            # So, we need to check that special case.
-            return self.check_call(
-                callee=self.combine_function_signatures(cast("list[ProperType]", matches)),
-                args=args,
-                arg_kinds=arg_kinds,
-                arg_names=arg_names,
-                context=context,
-                callable_name=callable_name,
-                object_type=object_type,
-            )
+            else:
+                return self.check_call(
+                    callee=AnyType(TypeOfAny.special_form),
+                    args=args,
+                    arg_kinds=arg_kinds,
+                    arg_names=arg_names,
+                    context=context,
+                    callable_name=callable_name,
+                    object_type=object_type,
+                )
         else:
             # Success! No ambiguity; return the first match.
             self.chk.store_types(type_maps[0])
@@ -3165,8 +3144,6 @@ def combine_function_signatures(self, types: list[ProperType]) -> AnyType | Call
         new_args: list[list[Type]] = [[] for _ in range(len(callables[0].arg_types))]
         new_kinds = list(callables[0].arg_kinds)
         new_returns: list[Type] = []
-        new_type_guards: list[Type] = []
-        new_type_narrowers: list[Type] = []
 
         too_complex = False
         for target in callables:
@@ -3193,25 +3170,8 @@ def combine_function_signatures(self, types: list[ProperType]) -> AnyType | Call
             for i, arg in enumerate(target.arg_types):
                 new_args[i].append(arg)
             new_returns.append(target.ret_type)
-            if target.type_guard:
-                new_type_guards.append(target.type_guard)
-            if target.type_is:
-                new_type_narrowers.append(target.type_is)
-
-        if new_type_guards and new_type_narrowers:
-            # They cannot be defined at the same time,
-            # declaring this function as too complex!
-            too_complex = True
-            union_type_guard = None
-            union_type_is = None
-        else:
-            union_type_guard = make_simplified_union(new_type_guards) if new_type_guards else None
-            union_type_is = (
-                make_simplified_union(new_type_narrowers) if new_type_narrowers else None
-            )
 
         union_return = make_simplified_union(new_returns)
-
         if too_complex:
             any = AnyType(TypeOfAny.special_form)
             return callables[0].copy_modified(
@@ -3221,8 +3181,6 @@ def combine_function_signatures(self, types: list[ProperType]) -> AnyType | Call
                 ret_type=union_return,
                 variables=variables,
                 implicit=True,
-                type_guard=union_type_guard,
-                type_is=union_type_is,
             )
 
         final_args = []
@@ -3236,8 +3194,6 @@ def combine_function_signatures(self, types: list[ProperType]) -> AnyType | Call
             ret_type=union_return,
             variables=variables,
             implicit=True,
-            type_guard=union_type_guard,
-            type_is=union_type_is,
         )
 
     def erased_signature_similarity(
@@ -6594,25 +6550,6 @@ def all_same_types(types: list[Type]) -> bool:
     return all(is_same_type(t, types[0]) for t in types[1:])
 
 
-def all_same_type_narrowers(types: list[CallableType]) -> bool:
-    if len(types) <= 1:
-        return True
-
-    type_guards: list[Type] = []
-    type_narrowers: list[Type] = []
-
-    for typ in types:
-        if typ.type_guard:
-            type_guards.append(typ.type_guard)
-        if typ.type_is:
-            type_narrowers.append(typ.type_is)
-    if type_guards and type_narrowers:
-        # Some overloads declare `TypeGuard` and some declare `TypeIs`,
-        # we cannot handle this in a union.
-        return False
-    return all_same_types(type_guards) and all_same_types(type_narrowers)
-
-
 def merge_typevars_in_callables_by_name(
     callables: Sequence[CallableType],
 ) -> tuple[list[CallableType], list[TypeVarType]]:
diff --git a/test-data/unit/check-typeguard.test b/test-data/unit/check-typeguard.test
index 00bf7d211927..94aa7ec6ffb8 100644
--- a/test-data/unit/check-typeguard.test
+++ b/test-data/unit/check-typeguard.test
@@ -731,62 +731,6 @@ assert a(x=x)
 reveal_type(x)  # N: Revealed type is "builtins.int"
 [builtins fixtures/tuple.pyi]
 
-[case testTypeGuardInOverloads]
-from typing import Any, overload, Union
-from typing_extensions import TypeGuard
-
-@overload
-def func1(x: str) -> TypeGuard[str]:
-    ...
-
-@overload
-def func1(x: int) -> TypeGuard[int]:
-    ...
-
-def func1(x: Any) -> Any:
-    return True
-
-def func2(val: Any):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "Union[builtins.str, builtins.int]"
-    else:
-        reveal_type(val)  # N: Revealed type is "Any"
-
-def func3(val: Union[int, str]):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "Union[builtins.int, builtins.str]"
-    else:
-        reveal_type(val)  # N: Revealed type is "Union[builtins.int, builtins.str]"
-
-def func4(val: int):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "builtins.int"
-    else:
-        reveal_type(val)  # N: Revealed type is "builtins.int"
-[builtins fixtures/tuple.pyi]
-
-[case testTypeIsInOverloadsSameReturn]
-from typing import Any, overload, Union
-from typing_extensions import TypeGuard
-
-@overload
-def func1(x: str) -> TypeGuard[str]:
-    ...
-
-@overload
-def func1(x: int) -> TypeGuard[str]:
-    ...
-
-def func1(x: Any) -> Any:
-    return True
-
-def func2(val: Union[int, str]):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "builtins.str"
-    else:
-        reveal_type(val)  # N: Revealed type is "Union[builtins.int, builtins.str]"
-[builtins fixtures/tuple.pyi]
-
 [case testTypeGuardRestrictAwaySingleInvariant]
 from typing import List
 from typing_extensions import TypeGuard
diff --git a/test-data/unit/check-typeis.test b/test-data/unit/check-typeis.test
index 8cdcf8634788..356b1abfdf63 100644
--- a/test-data/unit/check-typeis.test
+++ b/test-data/unit/check-typeis.test
@@ -818,125 +818,6 @@ accept_typeguard(typeguard)
 
 [builtins fixtures/tuple.pyi]
 
-[case testTypeIsInOverloads]
-from typing import Any, overload, Union
-from typing_extensions import TypeIs
-
-@overload
-def func1(x: str) -> TypeIs[str]:
-    ...
-
-@overload
-def func1(x: int) -> TypeIs[int]:
-    ...
-
-def func1(x: Any) -> Any:
-    return True
-
-def func2(val: Any):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "Union[builtins.str, builtins.int]"
-    else:
-        reveal_type(val)  # N: Revealed type is "Any"
-
-def func3(val: Union[int, str]):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "Union[builtins.int, builtins.str]"
-    else:
-        reveal_type(val)
-
-def func4(val: int):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "builtins.int"
-    else:
-        reveal_type(val)
-[builtins fixtures/tuple.pyi]
-
-[case testTypeIsInOverloadsSameReturn]
-from typing import Any, overload, Union
-from typing_extensions import TypeIs
-
-@overload
-def func1(x: str) -> TypeIs[str]:
-    ...
-
-@overload
-def func1(x: int) -> TypeIs[str]:  # type: ignore
-    ...
-
-def func1(x: Any) -> Any:
-    return True
-
-def func2(val: Union[int, str]):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "builtins.str"
-    else:
-        reveal_type(val)  # N: Revealed type is "builtins.int"
-[builtins fixtures/tuple.pyi]
-
-[case testTypeIsInOverloadsUnionizeError]
-from typing import Any, overload, Union
-from typing_extensions import TypeIs, TypeGuard
-
-@overload
-def func1(x: str) -> TypeIs[str]:
-    ...
-
-@overload
-def func1(x: int) -> TypeGuard[int]:
-    ...
-
-def func1(x: Any) -> Any:
-    return True
-
-def func2(val: Union[int, str]):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "Union[builtins.int, builtins.str]"
-    else:
-        reveal_type(val)  # N: Revealed type is "Union[builtins.int, builtins.str]"
-[builtins fixtures/tuple.pyi]
-
-[case testTypeIsInOverloadsUnionizeError2]
-from typing import Any, overload, Union
-from typing_extensions import TypeIs, TypeGuard
-
-@overload
-def func1(x: int) -> TypeGuard[int]:
-    ...
-
-@overload
-def func1(x: str) -> TypeIs[str]:
-    ...
-
-def func1(x: Any) -> Any:
-    return True
-
-def func2(val: Union[int, str]):
-    if func1(val):
-        reveal_type(val)  # N: Revealed type is "Union[builtins.int, builtins.str]"
-    else:
-        reveal_type(val)  # N: Revealed type is "Union[builtins.int, builtins.str]"
-[builtins fixtures/tuple.pyi]
-
-[case testTypeIsLikeIsDataclass]
-from typing import Any, overload, Union, Type
-from typing_extensions import TypeIs
-
-class DataclassInstance: ...
-
-@overload
-def is_dataclass(obj: type) -> TypeIs[Type[DataclassInstance]]: ...
-@overload
-def is_dataclass(obj: object) -> TypeIs[Union[DataclassInstance, Type[DataclassInstance]]]: ...
-
-def is_dataclass(obj: Union[type, object]) -> bool:
-    return False
-
-def func(arg: Any) -> None:
-    if is_dataclass(arg):
-        reveal_type(arg)  # N: Revealed type is "Union[Type[__main__.DataclassInstance], __main__.DataclassInstance]"
-[builtins fixtures/tuple.pyi]
-
 [case testTypeIsEnumOverlappingUnionExcludesIrrelevant]
 from enum import Enum
 from typing import Literal

From 8fe719ff3a8d1e26d3841a48df21ddf7d5b3c94d Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Thu, 29 May 2025 12:36:32 +0100
Subject: [PATCH 10/20] Add changelog for 1.16 (#19138)

Related to #18739.
---
 CHANGELOG.md | 415 +++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 405 insertions(+), 10 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5cc87cae5065..01d58ce6a1b3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,32 +2,173 @@
 
 ## Next Release
 
+## Mypy 1.16
+
+We’ve just uploaded mypy 1.16 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)).
+Mypy is a static type checker for Python. This release includes new features and bug fixes.
+You can install it as follows:
+
+    python3 -m pip install -U mypy
+
+You can read the full documentation for this release on [Read the Docs](http://mypy.readthedocs.io).
+
 ### Different Property Getter and Setter Types
 
-Mypy now supports using different types for property getter and setter.
+Mypy now supports using different types for a property getter and setter:
+
 ```python
 class A:
-    value: int
+    _value: int
 
     @property
-    def f(self) -> int:
-        return self.value
-    @f.setter
-    def f(self, x: str | int) -> None:
+    def foo(self) -> int:
+        return self._value
+
+    @foo.setter
+    def foo(self, x: str | int) -> None:
         try:
-            self.value = int(x)
+            self._value = int(x)
         except ValueError:
-            raise Exception(f"'{x}' is not a valid value for 'f'")
+            raise Exception(f"'{x}' is not a valid value for 'foo'")
 ```
+This was contributed by Ivan Levkivskyi (PR [18510](https://github.com/python/mypy/pull/18510)).
+
+### Flexible Variable Redefinitions (Experimental)
+
+Mypy now allows unannotated variables to be freely redefined with
+different types when using the experimental `--allow-redefinition-new`
+flag. You will also need to enable `--local-partial-types`. Mypy will
+now infer a union type when different types are assigned to a
+variable:
 
-Contributed by Ivan Levkivskyi (PR [18510](https://github.com/python/mypy/pull/18510))
+```py
+# mypy: allow-redefinition-new, local-partial-types
+
+def f(n: int, b: bool) -> int | str:
+    if b:
+        x = n
+    else:
+        x = str(n)
+    # Type of 'x' is int | str here.
+    return x
+```
+
+Without the new flag, mypy only supports inferring optional types (`X
+| None`) from multiple assignments, but now mypy can infer arbitrary
+union types.
+
+An unannotated variable can now also have different types in different
+code locations:
+
+```py
+# mypy: allow-redefinition-new, local-partial-types
+...
+
+if cond():
+    for x in range(n):
+        # Type of 'x' is 'int' here
+        ...
+else:
+    for x in ['a', 'b']:
+        # Type of 'x' is 'str' here
+        ...
+```
+
+We are planning to turn this flag on by default in mypy 2.0, along
+with `--local-partial-types`. The feature is still experimental and
+has known issues, and the semantics may still change in the
+future. You may need to update or add type annotations when switching
+to the new behavior, but if you encounter anything unexpected, please
+create a GitHub issue.
+
+This was contributed by Jukka Lehtosalo
+(PR [18727](https://github.com/python/mypy/pull/18727), PR [19153](https://github.com/python/mypy/pull/19153)).
+
+### Stricter Type Checking with Imprecise Types
+
+Mypy can now detect additional errors in code that uses `Any` types or has missing function annotations.
+
+When calling `dict.get(x, None)` on an object of type `dict[str, Any]`, this
+now results in an optional type (in the past it was `Any`):
+
+```python
+def f(d: dict[str, Any]) -> int:
+    # Error: Return value has type "Any | None" but expected "int"
+    return d.get("x", None)
+```
+
+Type narrowing using assignments can result in more precise types in
+the presence of `Any` types:
+
+```python
+def foo(): ...
+
+def bar(n: int) -> None:
+    x = foo()
+    # Type of 'x' is 'Any' here
+    if n > 5:
+        x = str(n)
+        # Type of 'x' is 'str' here
+```
+
+When using `--check-untyped-defs`, unannotated overrides are now
+checked more strictly against superclass definitions.
+
+Related PRs:
+
+ * Use union types instead of join in binder (Ivan Levkivskyi, PR [18538](https://github.com/python/mypy/pull/18538))
+ * Check superclass compatibility of untyped methods if `--check-untyped-defs` is set (Stanislav Terliakov, PR [18970](https://github.com/python/mypy/pull/18970))
+
+### Improvements to Attribute Resolution
+
+This release includes several fixes to inconsistent resolution of attribute, method and descriptor types.
+
+ * Consolidate descriptor handling (Ivan Levkivskyi, PR [18831](https://github.com/python/mypy/pull/18831))
+ * Make multiple inheritance checking use common semantics (Ivan Levkivskyi, PR [18876](https://github.com/python/mypy/pull/18876))
+ * Make method override checking use common semantics  (Ivan Levkivskyi, PR [18870](https://github.com/python/mypy/pull/18870))
+ * Fix descriptor overload selection (Ivan Levkivskyi, PR [18868](https://github.com/python/mypy/pull/18868))
+ * Handle union types when binding `self` (Ivan Levkivskyi, PR [18867](https://github.com/python/mypy/pull/18867))
+ * Make variable override checking use common semantics (Ivan Levkivskyi, PR [18847](https://github.com/python/mypy/pull/18847))
+ * Make descriptor handling behave consistently (Ivan Levkivskyi, PR [18831](https://github.com/python/mypy/pull/18831))
+
+### Make Implementation for Abstract Overloads Optional
+
+The implementation can now be omitted for abstract overloaded methods,
+even outside stubs:
+
+```py
+from abc import abstractmethod
+from typing import overload
+
+class C:
+    @abstractmethod
+    @overload
+    def foo(self, x: int) -> int: ...
+
+    @abstractmethod
+    @overload
+    def foo(self, x: str) -> str: ...
+
+    # No implementation required for "foo"
+```
+
+This was contributed by Ivan Levkivskyi (PR [18882](https://github.com/python/mypy/pull/18882)).
+
+### Option to Exclude Everything in .gitignore
+
+You can now use `--exclude-gitignore` to exclude everything in a
+`.gitignore` file from the mypy build. This behaves similar to
+excluding the paths using `--exclude`. We might enable this by default
+in a future mypy release.
+
+This was contributed by Ivan Levkivskyi (PR [18696](https://github.com/python/mypy/pull/18696)).
 
 ### Selectively Disable Deprecated Warnings
 
 It's now possible to selectively disable warnings generated from
 [`warnings.deprecated`](https://docs.python.org/3/library/warnings.html#warnings.deprecated)
 using the [`--deprecated-calls-exclude`](https://mypy.readthedocs.io/en/stable/command_line.html#cmdoption-mypy-deprecated-calls-exclude)
-option.
+option:
 
 ```python
 # mypy --enable-error-code deprecated
@@ -35,16 +176,269 @@ option.
 import foo
 
 foo.A().func()  # OK, the deprecated warning is ignored
+```
 
+```python
 # file foo.py
+
 from typing_extensions import deprecated
+
 class A:
     @deprecated("Use A.func2 instead")
     def func(self): pass
+
+    ...
 ```
 
 Contributed by Marc Mueller (PR [18641](https://github.com/python/mypy/pull/18641))
 
+### Annotating Native/Non-Native Classes in Mypyc
+
+You can now declare a class as a non-native class when compiling with
+mypyc. Unlike native classes, which are extension classes and have an
+immutable structure, non-native classes are normal Python classes at
+runtime and are fully dynamic.  Example:
+
+```python
+from mypy_extensions import mypyc_attr
+
+@mypyc_attr(native_class=False)
+class NonNativeClass:
+    ...
+
+o = NonNativeClass()
+
+# Ok, even if attribute "foo" not declared in class body
+setattr(o, "foo", 1)
+```
+
+Classes are native by default in compiled modules, but classes that
+use certain features (such as most metaclasses) are implicitly
+non-native.
+
+You can also explicitly declare a class as native. In this case mypyc
+will generate an error if it can't compile the class as a native
+class, instead of falling back to a non-native class:
+
+```python
+from mypy_extensions import mypyc_attr
+from foo import MyMeta
+
+# Error: Unsupported metaclass for a native class
+@mypyc_attr(native_class=True)
+class C(metaclass=MyMeta):
+    ...
+```
+
+Since native classes are significantly more efficient that non-native
+classes, you may want to ensure that certain classes always compiled
+as native classes.
+
+This feature was contributed by Valentin Stanciu (PR [18802](https://github.com/python/mypy/pull/18802)).
+
+### Mypyc Fixes and Improvements
+
+ * Improve documentation of native and non-native classes (Jukka Lehtosalo, PR [19154](https://github.com/python/mypy/pull/19154))
+ * Fix compilation when using Python 3.13 debug build (Valentin Stanciu, PR [19045](https://github.com/python/mypy/pull/19045))
+ * Show the reason why a class can't be a native class (Valentin Stanciu, PR [19016](https://github.com/python/mypy/pull/19016))
+ * Support await/yield while temporary values are live (Michael J. Sullivan, PR [16305](https://github.com/python/mypy/pull/16305))
+ * Fix spilling values with overlapping error values (Jukka Lehtosalo, PR [18961](https://github.com/python/mypy/pull/18961))
+ * Fix reference count of spilled register in async def (Jukka Lehtosalo, PR [18957](https://github.com/python/mypy/pull/18957))
+ * Add basic optimization for `sorted` (Marc Mueller, PR [18902](https://github.com/python/mypy/pull/18902))
+ * Fix access of class object in a type annotation (Advait Dixit, PR [18874](https://github.com/python/mypy/pull/18874))
+ * Optimize `list.__imul__` and `tuple.__mul__ `(Marc Mueller, PR [18887](https://github.com/python/mypy/pull/18887))
+ * Optimize `list.__add__`, `list.__iadd__` and `tuple.__add__` (Marc Mueller, PR [18845](https://github.com/python/mypy/pull/18845))
+ * Add and implement primitive `list.copy()` (exertustfm, PR [18771](https://github.com/python/mypy/pull/18771))
+ * Optimize `builtins.repr` (Marc Mueller, PR [18844](https://github.com/python/mypy/pull/18844))
+ * Support iterating over keys/values/items of dict-bound TypeVar and ParamSpec.kwargs (Stanislav Terliakov, PR [18789](https://github.com/python/mypy/pull/18789))
+ * Add efficient primitives for `str.strip()` etc. (Advait Dixit, PR [18742](https://github.com/python/mypy/pull/18742))
+ * Document that `strip()` etc. are optimized (Jukka Lehtosalo, PR [18793](https://github.com/python/mypy/pull/18793))
+ * Fix mypyc crash with enum type aliases (Valentin Stanciu, PR [18725](https://github.com/python/mypy/pull/18725))
+ * Optimize `str.find` and `str.rfind` (Marc Mueller, PR [18709](https://github.com/python/mypy/pull/18709))
+ * Optimize `str.__contains__` (Marc Mueller, PR [18705](https://github.com/python/mypy/pull/18705))
+ * Fix order of steal/unborrow in tuple unpacking (Ivan Levkivskyi, PR [18732](https://github.com/python/mypy/pull/18732))
+ * Optimize `str.partition` and `str.rpartition` (Marc Mueller, PR [18702](https://github.com/python/mypy/pull/18702))
+ * Optimize `str.startswith` and `str.endswith` with tuple argument (Marc Mueller, PR [18678](https://github.com/python/mypy/pull/18678))
+ * Improve `str.startswith` and `str.endswith` with tuple argument (Marc Mueller, PR [18703](https://github.com/python/mypy/pull/18703))
+ * `pythoncapi_compat`: don't define Py_NULL if it is already defined (Michael R. Crusoe, PR [18699](https://github.com/python/mypy/pull/18699))
+ * Optimize `str.splitlines` (Marc Mueller, PR [18677](https://github.com/python/mypy/pull/18677))
+ * Mark `dict.setdefault` as optimized (Marc Mueller, PR [18685](https://github.com/python/mypy/pull/18685))
+ * Support `__del__` methods (Advait Dixit, PR [18519](https://github.com/python/mypy/pull/18519))
+ * Optimize `str.rsplit` (Marc Mueller, PR [18673](https://github.com/python/mypy/pull/18673))
+ * Optimize `str.removeprefix` and `str.removesuffix` (Marc Mueller, PR [18672](https://github.com/python/mypy/pull/18672))
+ * Recognize literal types in `__match_args__` (Stanislav Terliakov, PR [18636](https://github.com/python/mypy/pull/18636))
+ * Fix non extension classes with attribute annotations using forward references (Valentin Stanciu, PR [18577](https://github.com/python/mypy/pull/18577))
+ * Use lower-case generic types such as `list[t]` in documentation (Jukka Lehtosalo, PR [18576](https://github.com/python/mypy/pull/18576))
+ * Improve support for `frozenset` (Marc Mueller, PR [18571](https://github.com/python/mypy/pull/18571))
+ * Fix wheel build for cp313-win (Marc Mueller, PR [18560](https://github.com/python/mypy/pull/18560))
+ * Reduce impact of immortality (introduced in Python 3.12) on reference counting performance (Jukka Lehtosalo, PR [18459](https://github.com/python/mypy/pull/18459))
+ * Update math error messages for 3.14 (Marc Mueller, PR [18534](https://github.com/python/mypy/pull/18534))
+ * Update math error messages for 3.14 (2) (Marc Mueller, PR [18949](https://github.com/python/mypy/pull/18949))
+ * Replace deprecated `_PyLong_new` with `PyLongWriter` API (Marc Mueller, PR [18532](https://github.com/python/mypy/pull/18532))
+
+### Fixes to Crashes
+
+ * Traverse module ancestors when traversing reachable graph nodes during dmypy update (Stanislav Terliakov, PR [18906](https://github.com/python/mypy/pull/18906))
+ * Fix crash on multiple unpacks in a bare type application (Stanislav Terliakov, PR [18857](https://github.com/python/mypy/pull/18857))
+ * Prevent crash when enum/TypedDict call is stored as a class attribute (Stanislav Terliakov, PR [18861](https://github.com/python/mypy/pull/18861))
+ * Fix crash on multiple unpacks in a bare type application (Stanislav Terliakov, PR [18857](https://github.com/python/mypy/pull/18857))
+ * Fix crash on type inference against non-normal callables (Ivan Levkivskyi, PR [18858](https://github.com/python/mypy/pull/18858))
+ * Fix crash on decorated getter in settable property (Ivan Levkivskyi, PR [18787](https://github.com/python/mypy/pull/18787))
+ * Fix crash on callable with `*args` and suffix against Any (Ivan Levkivskyi, PR [18781](https://github.com/python/mypy/pull/18781))
+ * Fix crash on deferred supertype and setter override (Ivan Levkivskyi, PR [18649](https://github.com/python/mypy/pull/18649))
+ * Fix crashes on incorrectly detected recursive aliases (Ivan Levkivskyi, PR [18625](https://github.com/python/mypy/pull/18625))
+ * Report that `NamedTuple` and `dataclass` are incompatile instead of crashing (Christoph Tyralla, PR [18633](https://github.com/python/mypy/pull/18633))
+ * Fix mypy daemon crash (Valentin Stanciu, PR [19087](https://github.com/python/mypy/pull/19087))
+
+### Performance Improvements
+
+These are specific to mypy. Mypyc-related performance improvements are discussed elsewhere.
+
+ * Speed up binding `self` in trivial cases (Ivan Levkivskyi, PR [19024](https://github.com/python/mypy/pull/19024))
+ * Small constraint solver optimization (Aaron Gokaslan, PR [18688](https://github.com/python/mypy/pull/18688))
+
+### Documentation Updates
+
+ * Improve documentation of `--strict` (lenayoung8, PR [18903](https://github.com/python/mypy/pull/18903))
+ * Remove a note about `from __future__ import annotations` (Ageev Maxim, PR [18915](https://github.com/python/mypy/pull/18915))
+ * Improve documentation on type narrowing (Tim Hoffmann, PR [18767](https://github.com/python/mypy/pull/18767))
+ * Fix metaclass usage example (Georg, PR [18686](https://github.com/python/mypy/pull/18686))
+ * Update documentation on `extra_checks` flag (Ivan Levkivskyi, PR [18537](https://github.com/python/mypy/pull/18537))
+
+### Stubgen Improvements
+
+ * Fix `TypeAlias` handling (Alexey Makridenko, PR [18960](https://github.com/python/mypy/pull/18960))
+ * Handle `arg=None` in C extension modules (Anthony Sottile, PR [18768](https://github.com/python/mypy/pull/18768))
+ * Fix valid type detection to allow pipe unions (Chad Dombrova, PR [18726](https://github.com/python/mypy/pull/18726))
+ * Include simple decorators in stub files (Marc Mueller, PR [18489](https://github.com/python/mypy/pull/18489))
+ * Support positional and keyword-only arguments in stubdoc (Paul Ganssle, PR [18762](https://github.com/python/mypy/pull/18762))
+ * Fall back to `Incomplete` if we are unable to determine the module name (Stanislav Terliakov, PR [19084](https://github.com/python/mypy/pull/19084))
+
+### Stubtest Improvements
+
+ * Make stubtest ignore `__slotnames__` (Nick Pope, PR [19077](https://github.com/python/mypy/pull/19077))
+ * Fix stubtest tests on 3.14 (Jelle Zijlstra, PR [19074](https://github.com/python/mypy/pull/19074))
+ * Support for `strict_bytes` in stubtest (Joren Hammudoglu, PR [19002](https://github.com/python/mypy/pull/19002))
+ * Understand override (Shantanu, PR [18815](https://github.com/python/mypy/pull/18815))
+ * Better checking of runtime arguments with dunder names (Shantanu, PR [18756](https://github.com/python/mypy/pull/18756))
+ * Ignore setattr and delattr inherited from object (Stephen Morton, PR [18325](https://github.com/python/mypy/pull/18325))
+
+### Miscellaneous Fixes and Improvements
+
+ * Add `--strict-bytes` to `--strict` (wyattscarpenter, PR [19049](https://github.com/python/mypy/pull/19049))
+ * Admit that Final variables are never redefined (Stanislav Terliakov, PR [19083](https://github.com/python/mypy/pull/19083))
+ * Add special support for `@django.cached_property` needed in `django-stubs` (sobolevn, PR [18959](https://github.com/python/mypy/pull/18959))
+ * Do not narrow types to `Never` with binder (Ivan Levkivskyi, PR [18972](https://github.com/python/mypy/pull/18972))
+ * Local forward references should precede global forward references (Ivan Levkivskyi, PR [19000](https://github.com/python/mypy/pull/19000))
+ * Do not cache module lookup results in incremental mode that may become invalid (Stanislav Terliakov, PR [19044](https://github.com/python/mypy/pull/19044))
+ * Only consider meta variables in ambiguous "any of" constraints (Stanislav Terliakov, PR [18986](https://github.com/python/mypy/pull/18986))
+ * Allow accessing `__init__` on final classes and when `__init__` is final (Stanislav Terliakov, PR [19035](https://github.com/python/mypy/pull/19035))
+ * Treat varargs as positional-only (A5rocks, PR [19022](https://github.com/python/mypy/pull/19022))
+ * Enable colored output for argparse help in Python 3.14 (Marc Mueller, PR [19021](https://github.com/python/mypy/pull/19021))
+ * Fix argparse for Python 3.14 (Marc Mueller, PR [19020](https://github.com/python/mypy/pull/19020))
+ * `dmypy suggest` can now suggest through contextmanager-based decorators (Anthony Sottile, PR [18948](https://github.com/python/mypy/pull/18948))
+ * Fix `__r<magic_methods>__` being used under the same `__<magic_method>__` hook (Arnav Jain, PR [18995](https://github.com/python/mypy/pull/18995))
+ * Prioritize `.pyi` from `-stubs` packages over bundled `.pyi` (Joren Hammudoglu, PR [19001](https://github.com/python/mypy/pull/19001))
+ * Fix missing subtype check case for `type[T]` (Stanislav Terliakov, PR [18975](https://github.com/python/mypy/pull/18975))
+ * Fixes to the detection of redundant casts (Anthony Sottile, PR [18588](https://github.com/python/mypy/pull/18588))
+ * Make some parse errors non-blocking (Shantanu, PR [18941](https://github.com/python/mypy/pull/18941))
+ * Fix PEP 695 type alias with a mix of type arguments (PEP 696) (Marc Mueller, PR [18919](https://github.com/python/mypy/pull/18919))
+ * Allow deeper recursion in mypy daemon, better error reporting (Carter Dodd, PR [17707](https://github.com/python/mypy/pull/17707))
+ * Fix swapped errors for frozen/non-frozen dataclass inheritance (Nazrawi Demeke, PR [18918](https://github.com/python/mypy/pull/18918))
+ * Fix incremental issue with namespace packages (Shantanu, PR [18907](https://github.com/python/mypy/pull/18907))
+ * Exclude irrelevant members when narrowing union overlapping with enum (Stanislav Terliakov, PR [18897](https://github.com/python/mypy/pull/18897))
+ * Flatten union before contracting literals when checking subtyping (Stanislav Terliakov, PR [18898](https://github.com/python/mypy/pull/18898))
+ * Do not add `kw_only` dataclass fields to `__match_args__` (sobolevn, PR [18892](https://github.com/python/mypy/pull/18892))
+ * Fix error message when returning long tuple with type mismatch (Thomas Mattone, PR [18881](https://github.com/python/mypy/pull/18881))
+ * Treat `TypedDict` (old-style) aliases as regular `TypedDict`s (Stanislav Terliakov, PR [18852](https://github.com/python/mypy/pull/18852))
+ * Warn about unused `type: ignore` comments when error code is disabled (Brian Schubert, PR [18849](https://github.com/python/mypy/pull/18849))
+ * Reject duplicate `ParamSpec.{args,kwargs}` at call site (Stanislav Terliakov, PR [18854](https://github.com/python/mypy/pull/18854))
+ * Make detection of enum members more consistent (sobolevn, PR [18675](https://github.com/python/mypy/pull/18675))
+ * Admit that `**kwargs` mapping subtypes may have no direct type parameters (Stanislav Terliakov, PR [18850](https://github.com/python/mypy/pull/18850))
+ * Don't suggest `types-setuptools` for `pkg_resources` (Shantanu, PR [18840](https://github.com/python/mypy/pull/18840))
+ * Suggest `scipy-stubs` for `scipy` as non-typeshed stub package (Joren Hammudoglu, PR [18832](https://github.com/python/mypy/pull/18832))
+ * Narrow tagged unions in match statements (Gene Parmesan Thomas, PR [18791](https://github.com/python/mypy/pull/18791))
+ * Consistently store settable property type (Ivan Levkivskyi, PR [18774](https://github.com/python/mypy/pull/18774))
+ * Do not blindly undefer on leaving function (Ivan Levkivskyi, PR [18674](https://github.com/python/mypy/pull/18674))
+ * Process superclass methods before subclass methods in semanal (Ivan Levkivskyi, PR [18723](https://github.com/python/mypy/pull/18723))
+ * Only defer top-level functions (Ivan Levkivskyi, PR [18718](https://github.com/python/mypy/pull/18718))
+ * Add one more type-checking pass (Ivan Levkivskyi, PR [18717](https://github.com/python/mypy/pull/18717))
+ * Properly account for `member` and `nonmember` in enums (sobolevn, PR [18559](https://github.com/python/mypy/pull/18559))
+ * Fix instance vs tuple subtyping edge case (Ivan Levkivskyi, PR [18664](https://github.com/python/mypy/pull/18664))
+ * Improve handling of Any/object in variadic generics (Ivan Levkivskyi, PR [18643](https://github.com/python/mypy/pull/18643))
+ * Fix handling of named tuples in class match pattern (Ivan Levkivskyi, PR [18663](https://github.com/python/mypy/pull/18663))
+ * Fix regression for user config files (Shantanu, PR [18656](https://github.com/python/mypy/pull/18656))
+ * Fix dmypy socket issue on GNU/Hurd (Mattias Ellert, PR [18630](https://github.com/python/mypy/pull/18630))
+ * Don't assume that for loop body index variable is always set (Jukka Lehtosalo, PR [18631](https://github.com/python/mypy/pull/18631))
+ * Fix overlap check for variadic generics (Ivan Levkivskyi, PR [18638](https://github.com/python/mypy/pull/18638))
+ * Improve support for `functools.partial` of overloaded callable protocol (Shantanu, PR [18639](https://github.com/python/mypy/pull/18639))
+ * Allow lambdas in `except*` clauses (Stanislav Terliakov, PR [18620](https://github.com/python/mypy/pull/18620))
+ * Fix trailing commas in many multiline string options in `pyproject.toml` (sobolevn, PR [18624](https://github.com/python/mypy/pull/18624))
+ * Allow trailing commas for `files` setting in `mypy.ini` and `setup.ini` (sobolevn, PR [18621](https://github.com/python/mypy/pull/18621))
+ * Fix "not callable" issue for `@dataclass(frozen=True)` with `Final` attr (sobolevn, PR [18572](https://github.com/python/mypy/pull/18572))
+ * Add missing TypedDict special case when checking member access (Stanislav Terliakov, PR [18604](https://github.com/python/mypy/pull/18604))
+ * Use lower case `list` and `dict` in invariance notes (Jukka Lehtosalo, PR [18594](https://github.com/python/mypy/pull/18594))
+ * Fix inference when class and instance match protocol (Ivan Levkivskyi, PR [18587](https://github.com/python/mypy/pull/18587))
+ * Remove support for `builtins.Any` (Marc Mueller, PR [18578](https://github.com/python/mypy/pull/18578))
+ * Update the overlapping check for tuples to account for NamedTuples (A5rocks, PR [18564](https://github.com/python/mypy/pull/18564))
+ * Fix `@deprecated` (PEP 702) with normal overloaded methods (Christoph Tyralla, PR [18477](https://github.com/python/mypy/pull/18477))
+ * Start propagating end columns/lines for `type-arg` errors (A5rocks, PR [18533](https://github.com/python/mypy/pull/18533))
+ * Improve handling of `type(x) is Foo` checks (Stanislav Terliakov, PR [18486](https://github.com/python/mypy/pull/18486))
+ * Suggest `typing.Literal` for exit-return error messages (Marc Mueller, PR [18541](https://github.com/python/mypy/pull/18541))
+ * Allow redefinitions in except/else/finally (Stanislav Terliakov, PR [18515](https://github.com/python/mypy/pull/18515))
+ * Disallow setting Python version using inline config (Shantanu, PR [18497](https://github.com/python/mypy/pull/18497))
+ * Improve type inference in tuple multiplication plugin (Shantanu, PR [18521](https://github.com/python/mypy/pull/18521))
+ * Add missing line number to `yield from` with wrong type (Stanislav Terliakov, PR [18518](https://github.com/python/mypy/pull/18518))
+ * Hint at argument names when formatting callables with compatible return types in error messages (Stanislav Terliakov, PR [18495](https://github.com/python/mypy/pull/18495))
+ * Add better naming and improve compatibility for ad hoc intersections of instances (Christoph Tyralla, PR [18506](https://github.com/python/mypy/pull/18506))
+
+### Acknowledgements
+
+Thanks to all mypy contributors who contributed to this release:
+
+- A5rocks
+- Aaron Gokaslan
+- Advait Dixit
+- Ageev Maxim
+- Alexey Makridenko
+- Ali Hamdan
+- Anthony Sottile
+- Arnav Jain
+- Brian Schubert
+- bzoracler
+- Carter Dodd
+- Chad Dombrova
+- Christoph Tyralla
+- Dimitri Papadopoulos Orfanos
+- Emma Smith
+- exertustfm
+- Gene Parmesan Thomas
+- Georg
+- Ivan Levkivskyi
+- Jared Hance
+- Jelle Zijlstra
+- Joren Hammudoglu
+- lenayoung8
+- Marc Mueller
+- Mattias Ellert
+- Michael J. Sullivan
+- Michael R. Crusoe
+- Nazrawi Demeke
+- Nick Pope
+- Paul Ganssle
+- Shantanu
+- sobolevn
+- Stanislav Terliakov
+- Stephen Morton
+- Thomas Mattone
+- Tim Hoffmann
+- Tim Ruffing
+- Valentin Stanciu
+- Wesley Collin Wright
+- wyattscarpenter
+
+I’d also like to thank my employer, Dropbox, for supporting mypy development.
+
 ## Mypy 1.15
 
 We’ve just uploaded mypy 1.15 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)).
@@ -408,6 +802,7 @@ This was contributed by Marc Mueller (PR [18014](https://github.com/python/mypy/
 
 ### Other Notables Fixes and Improvements
 
+ * Allow enum members to have type objects as values (Jukka Lehtosalo, PR [19160](https://github.com/python/mypy/pull/19160))
  * Show `Protocol` `__call__` for arguments with incompatible types (MechanicalConstruct, PR [18214](https://github.com/python/mypy/pull/18214))
  * Make join and meet symmetric with `strict_optional` (MechanicalConstruct, PR [18227](https://github.com/python/mypy/pull/18227))
  * Preserve block unreachablility when checking function definitions with constrained TypeVars (Brian Schubert, PR [18217](https://github.com/python/mypy/pull/18217))

From 9e72e9601f4c2fb6866cfec98fc40a31c91ccdb0 Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Thu, 29 May 2025 12:38:56 +0100
Subject: [PATCH 11/20] Update version to 1.16.0

---
 mypy/version.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mypy/version.py b/mypy/version.py
index ffebfb7aa9ad..34fb2f642c5e 100644
--- a/mypy/version.py
+++ b/mypy/version.py
@@ -8,7 +8,7 @@
 # - Release versions have the form "1.2.3".
 # - Dev versions have the form "1.2.3+dev" (PLUS sign to conform to PEP 440).
 # - Before 1.0 we had the form "0.NNN".
-__version__ = "1.16.0+dev"
+__version__ = "1.16.0"
 base_version = __version__
 
 mypy_dir = os.path.abspath(os.path.dirname(os.path.dirname(__file__)))

From 9b079f6592740a51c0e629728eeb0324ad85126f Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Wed, 11 Jun 2025 13:25:18 +0100
Subject: [PATCH 12/20] Bump version to 1.16.1+dev

---
 mypy/version.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mypy/version.py b/mypy/version.py
index 34fb2f642c5e..d2d42a386dec 100644
--- a/mypy/version.py
+++ b/mypy/version.py
@@ -8,7 +8,7 @@
 # - Release versions have the form "1.2.3".
 # - Dev versions have the form "1.2.3+dev" (PLUS sign to conform to PEP 440).
 # - Before 1.0 we had the form "0.NNN".
-__version__ = "1.16.0"
+__version__ = "1.16.1+dev"
 base_version = __version__
 
 mypy_dir = os.path.abspath(os.path.dirname(os.path.dirname(__file__)))

From 0a4f28431faa18e59d35bc269cb0ea6c00810653 Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Tue, 3 Jun 2025 08:18:05 +0100
Subject: [PATCH 13/20] Fix crash on invalid property inside its own body
 (#19208)

Fixes https://github.com/python/mypy/issues/19205
---
 mypy/checkmember.py               |  4 ++++
 test-data/unit/check-classes.test | 13 +++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/mypy/checkmember.py b/mypy/checkmember.py
index cc104fed0752..4821c622cb0c 100644
--- a/mypy/checkmember.py
+++ b/mypy/checkmember.py
@@ -974,6 +974,10 @@ def expand_and_bind_callable(
     assert isinstance(expanded, CallableType)
     if var.is_settable_property and mx.is_lvalue and var.setter_type is not None:
         # TODO: use check_call() to infer better type, same as for __set__().
+        if not expanded.arg_types:
+            # This can happen when accessing invalid property from its own body,
+            # error will be reported elsewhere.
+            return AnyType(TypeOfAny.from_error)
         return expanded.arg_types[0]
     else:
         return expanded.ret_type
diff --git a/test-data/unit/check-classes.test b/test-data/unit/check-classes.test
index e0ea00aee361..59204cc31c43 100644
--- a/test-data/unit/check-classes.test
+++ b/test-data/unit/check-classes.test
@@ -8726,3 +8726,16 @@ class Fields:
 reveal_type(Fields.bool_f)  # N: Revealed type is "__main__.BoolField"
 reveal_type(Fields.int_f)  # N: Revealed type is "__main__.NumField"
 reveal_type(Fields.custom_f)  # N: Revealed type is "__main__.AnyField[__main__.Custom]"
+
+[case testRecursivePropertyWithInvalidSetterNoCrash]
+class NoopPowerResource:
+    _hardware_type: int
+
+    @property
+    def hardware_type(self) -> int:
+        return self._hardware_type
+
+    @hardware_type.setter
+    def hardware_type(self) -> None:  # E: Invalid property setter signature
+        self.hardware_type = None  # Note: intentionally recursive
+[builtins fixtures/property.pyi]

From c39f5e73c47182e51c5d8d488f7cc7301257c974 Mon Sep 17 00:00:00 2001
From: Advait Dixit <48302999+advait-dixit@users.noreply.github.com>
Date: Mon, 2 Jun 2025 07:20:25 -0700
Subject: [PATCH 14/20] [mypyc] Fixing condition for handling user-defined
 __del__ (#19188)

Fixes #19175.

Conditions for generating and invoking `del` method were not consistent.

As things currently stand, this pull request fixes the crash. However, for classes that derive from Python built-ins, user-defined `__del__` will not be invoked.
---
 mypyc/codegen/emitclass.py       |  6 +++---
 mypyc/test-data/run-classes.test | 21 +++++++++++++++++++++
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/mypyc/codegen/emitclass.py b/mypyc/codegen/emitclass.py
index c5191e5fb939..9cb9074b9fc4 100644
--- a/mypyc/codegen/emitclass.py
+++ b/mypyc/codegen/emitclass.py
@@ -304,9 +304,6 @@ def emit_line() -> None:
         emit_line()
         generate_dealloc_for_class(cl, dealloc_name, clear_name, bool(del_method), emitter)
         emit_line()
-        if del_method:
-            generate_finalize_for_class(del_method, finalize_name, emitter)
-            emit_line()
 
         if cl.allow_interpreted_subclasses:
             shadow_vtable_name: str | None = generate_vtables(
@@ -317,6 +314,9 @@ def emit_line() -> None:
             shadow_vtable_name = None
         vtable_name = generate_vtables(cl, vtable_setup_name, vtable_name, emitter, shadow=False)
         emit_line()
+    if del_method:
+        generate_finalize_for_class(del_method, finalize_name, emitter)
+        emit_line()
     if needs_getseters:
         generate_getseter_declarations(cl, emitter)
         emit_line()
diff --git a/mypyc/test-data/run-classes.test b/mypyc/test-data/run-classes.test
index 97bc063dd8ea..288f281c0a94 100644
--- a/mypyc/test-data/run-classes.test
+++ b/mypyc/test-data/run-classes.test
@@ -2754,6 +2754,21 @@ def test_function():
     assert(isinstance(d.fitem, ForwardDefinedClass))
     assert(isinstance(d.fitems, ForwardDefinedClass))
 
+[case testDelForDictSubclass-xfail]
+# The crash in issue mypy#19175 is fixed.
+# But, for classes that derive from built-in Python classes, user-defined __del__ method is not
+# being invoked.
+class DictSubclass(dict):
+    def __del__(self):
+        print("deleting DictSubclass...")
+
+[file driver.py]
+import native
+native.DictSubclass()
+
+[out]
+deleting DictSubclass...
+
 [case testDel]
 class A:
     def __del__(self):
@@ -2774,6 +2789,12 @@ class C(B):
 class D(A):
     pass
 
+# Just make sure that this class compiles (see issue mypy#19175). testDelForDictSubclass tests for
+# correct output.
+class NormDict(dict):
+    def __del__(self) -> None:
+        pass
+
 [file driver.py]
 import native
 native.C()

From cb3c6ec6a7aaa96a0e26768a946ac63ea14115f2 Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Tue, 3 Jun 2025 18:25:02 +0100
Subject: [PATCH 15/20] Fix crash on partial type used as context (#19216)

Fixes https://github.com/python/mypy/issues/19213
---
 mypy/checker.py                     |  4 +++-
 test-data/unit/check-inference.test | 21 +++++++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/mypy/checker.py b/mypy/checker.py
index 9c389cccd95f..cb465b390aa6 100644
--- a/mypy/checker.py
+++ b/mypy/checker.py
@@ -3426,7 +3426,9 @@ def check_compatibility_all_supers(self, lvalue: RefExpr, rvalue: Expression) ->
             # store the rvalue type on the variable.
             actual_lvalue_type = None
             if lvalue_node.is_inferred and not lvalue_node.explicit_self_type:
-                rvalue_type = self.expr_checker.accept(rvalue, lvalue_node.type)
+                # Don't use partial types as context, similar to regular code path.
+                ctx = lvalue_node.type if not isinstance(lvalue_node.type, PartialType) else None
+                rvalue_type = self.expr_checker.accept(rvalue, ctx)
                 actual_lvalue_type = lvalue_node.type
                 lvalue_node.type = rvalue_type
             lvalue_type, _ = self.node_type_from_base(lvalue_node.name, lvalue_node.info, lvalue)
diff --git a/test-data/unit/check-inference.test b/test-data/unit/check-inference.test
index 25565946158e..093924ab2e26 100644
--- a/test-data/unit/check-inference.test
+++ b/test-data/unit/check-inference.test
@@ -3979,3 +3979,24 @@ def check(mapping: Mapping[str, _T]) -> None:
     reveal_type(ok1)  # N: Revealed type is "Union[_T`-1, builtins.str]"
     ok2: Union[_T, str] = mapping.get("", "")
 [builtins fixtures/tuple.pyi]
+
+[case testNoCrashOnPartialTypeAsContext]
+from typing import overload, TypeVar, Optional, Protocol
+
+T = TypeVar("T")
+class DbManager(Protocol):
+    @overload
+    def get(self, key: str) -> Optional[T]:
+        pass
+
+    @overload
+    def get(self, key: str, default: T) -> T:
+        pass
+
+class Foo:
+    def __init__(self, db: DbManager, bar: bool) -> None:
+        if bar:
+            self.qux = db.get("qux")
+        else:
+            self.qux = {}  # E: Need type annotation for "qux" (hint: "qux: Dict[<type>, <type>] = ...")
+[builtins fixtures/dict.pyi]

From c86480ce51e4bb6db21f4b3f0b3ec8833aafc8ce Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Sun, 1 Jun 2025 02:30:37 +0100
Subject: [PATCH 16/20] Tighten metaclass __call__ handling in protocols
 (#19191)

Fixes https://github.com/python/mypy/issues/19184

This fixes an (edge-case) regression introduced in 1.16. Fix is
straightforward, only ignore `__call__` if it comes from an _actual_
metaclass.
---
 mypy/constraints.py                 |  4 ++--
 mypy/nodes.py                       |  4 ++--
 mypy/typeops.py                     |  2 +-
 test-data/unit/check-protocols.test | 22 ++++++++++++++++++++++
 4 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/mypy/constraints.py b/mypy/constraints.py
index 8e7a30e05ffb..73b7ec7954a4 100644
--- a/mypy/constraints.py
+++ b/mypy/constraints.py
@@ -1066,8 +1066,8 @@ def infer_constraints_from_protocol_members(
                     inst, erase_typevars(temp), ignore_pos_arg_names=True
                 ):
                     continue
-            # This exception matches the one in subtypes.py, see PR #14121 for context.
-            if member == "__call__" and instance.type.is_metaclass():
+            # This exception matches the one in typeops.py, see PR #14121 for context.
+            if member == "__call__" and instance.type.is_metaclass(precise=True):
                 continue
             res.extend(infer_constraints(temp, inst, self.direction))
             if mypy.subtypes.IS_SETTABLE in mypy.subtypes.get_member_flags(member, protocol):
diff --git a/mypy/nodes.py b/mypy/nodes.py
index 2fb459142066..9a9403722a16 100644
--- a/mypy/nodes.py
+++ b/mypy/nodes.py
@@ -3371,11 +3371,11 @@ def calculate_metaclass_type(self) -> mypy.types.Instance | None:
                 return c
         return None
 
-    def is_metaclass(self) -> bool:
+    def is_metaclass(self, *, precise: bool = False) -> bool:
         return (
             self.has_base("builtins.type")
             or self.fullname == "abc.ABCMeta"
-            or self.fallback_to_any
+            or (self.fallback_to_any and not precise)
         )
 
     def has_base(self, fullname: str) -> bool:
diff --git a/mypy/typeops.py b/mypy/typeops.py
index bcf946900563..3715081ae173 100644
--- a/mypy/typeops.py
+++ b/mypy/typeops.py
@@ -1257,7 +1257,7 @@ def named_type(fullname: str) -> Instance:
 
         return type_object_type(left.type, named_type)
 
-    if member == "__call__" and left.type.is_metaclass():
+    if member == "__call__" and left.type.is_metaclass(precise=True):
         # Special case: we want to avoid falling back to metaclass __call__
         # if constructor signature didn't match, this can cause many false negatives.
         return None
diff --git a/test-data/unit/check-protocols.test b/test-data/unit/check-protocols.test
index 34e3f3e88080..56c3d72d23e2 100644
--- a/test-data/unit/check-protocols.test
+++ b/test-data/unit/check-protocols.test
@@ -4460,3 +4460,25 @@ f2(a4)  # E: Argument 1 to "f2" has incompatible type "A4"; expected "P2" \
         # N:     foo: expected "B1", got "str" \
         # N:     foo: expected setter type "C1", got "str"
 [builtins fixtures/property.pyi]
+
+[case testInferCallableProtoWithAnySubclass]
+from typing import Any, Generic, Protocol, TypeVar
+
+T = TypeVar("T", covariant=True)
+
+Unknown: Any
+class Mock(Unknown):
+    def __init__(self, **kwargs: Any) -> None: ...
+    def __call__(self, *args: Any, **kwargs: Any) -> Any: ...
+
+class Factory(Protocol[T]):
+    def __call__(self, **kwargs: Any) -> T: ...
+
+
+class Test(Generic[T]):
+    def __init__(self, f: Factory[T]) -> None:
+        ...
+
+t = Test(Mock())
+reveal_type(t)  # N: Revealed type is "__main__.Test[Any]"
+[builtins fixtures/dict.pyi]

From c20fd7838338cd65d6c7c6e252eda85996cfc98e Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Thu, 5 Jun 2025 15:09:36 +0100
Subject: [PATCH 17/20] Handle assignment of bound methods in class bodies
 (#19233)

Fixes https://github.com/python/mypy/issues/18438
Fixes https://github.com/python/mypy/issues/19146

Surprisingly, a very small change is sufficient to replicate Python
runtime behavior for all the important cases (see `checkmember.py`). I
also replace the `bound_args` argument of `CallableType`, that was
mostly unused, with a flag (as suggested by @JukkaL) and make sure it is
properly set/preserved everywhere.
---
 mypy/checker.py                       |  2 +-
 mypy/checkexpr.py                     |  2 +-
 mypy/checkmember.py                   |  4 +--
 mypy/fixup.py                         |  3 --
 mypy/messages.py                      |  4 +--
 mypy/server/astdiff.py                |  1 +
 mypy/typeops.py                       |  3 +-
 mypy/types.py                         | 20 ++++++-------
 test-data/unit/check-classes.test     |  2 +-
 test-data/unit/check-functions.test   | 42 +++++++++++++++++++++++++++
 test-data/unit/check-incremental.test | 24 +++++++++++++++
 test-data/unit/fine-grained.test      | 24 +++++++++++++++
 12 files changed, 110 insertions(+), 21 deletions(-)

diff --git a/mypy/checker.py b/mypy/checker.py
index cb465b390aa6..5a5d19cc0006 100644
--- a/mypy/checker.py
+++ b/mypy/checker.py
@@ -2448,7 +2448,7 @@ def erase_override(t: Type) -> Type:
                     if not is_subtype(original_arg_type, erase_override(override_arg_type)):
                         context: Context = node
                         if isinstance(node, FuncDef) and not node.is_property:
-                            arg_node = node.arguments[i + len(override.bound_args)]
+                            arg_node = node.arguments[i + override.bound()]
                             if arg_node.line != -1:
                                 context = arg_node
                         self.msg.argument_incompatible_with_supertype(
diff --git a/mypy/checkexpr.py b/mypy/checkexpr.py
index f375c14c5fc4..df0e9bdaedde 100644
--- a/mypy/checkexpr.py
+++ b/mypy/checkexpr.py
@@ -4970,7 +4970,7 @@ def apply_type_arguments_to_callable(
                         tp.fallback,
                         name="tuple",
                         definition=tp.definition,
-                        bound_args=tp.bound_args,
+                        is_bound=tp.is_bound,
                     )
                 self.msg.incompatible_type_application(
                     min_arg_count, len(type_vars), len(args), ctx
diff --git a/mypy/checkmember.py b/mypy/checkmember.py
index 4821c622cb0c..ea76a6cc304f 100644
--- a/mypy/checkmember.py
+++ b/mypy/checkmember.py
@@ -916,7 +916,7 @@ def analyze_var(
             bound_items = []
             for ct in call_type.items if isinstance(call_type, UnionType) else [call_type]:
                 p_ct = get_proper_type(ct)
-                if isinstance(p_ct, FunctionLike) and not p_ct.is_type_obj():
+                if isinstance(p_ct, FunctionLike) and (not p_ct.bound() or var.is_property):
                     item = expand_and_bind_callable(p_ct, var, itype, name, mx, is_trivial_self)
                 else:
                     item = expand_without_binding(ct, var, itype, original_itype, mx)
@@ -1503,6 +1503,6 @@ def bind_self_fast(method: F, original_type: Type | None = None) -> F:
         arg_types=method.arg_types[1:],
         arg_kinds=method.arg_kinds[1:],
         arg_names=method.arg_names[1:],
-        bound_args=[original_type],
+        is_bound=True,
     )
     return cast(F, res)
diff --git a/mypy/fixup.py b/mypy/fixup.py
index 8e7cd40544bf..0e9c186fd42a 100644
--- a/mypy/fixup.py
+++ b/mypy/fixup.py
@@ -271,9 +271,6 @@ def visit_callable_type(self, ct: CallableType) -> None:
             ct.ret_type.accept(self)
         for v in ct.variables:
             v.accept(self)
-        for arg in ct.bound_args:
-            if arg:
-                arg.accept(self)
         if ct.type_guard is not None:
             ct.type_guard.accept(self)
         if ct.type_is is not None:
diff --git a/mypy/messages.py b/mypy/messages.py
index 2e07d7f63498..47e7d20dde78 100644
--- a/mypy/messages.py
+++ b/mypy/messages.py
@@ -644,8 +644,8 @@ def incompatible_argument(
         callee_name = callable_name(callee)
         if callee_name is not None:
             name = callee_name
-            if callee.bound_args and callee.bound_args[0] is not None:
-                base = format_type(callee.bound_args[0], self.options)
+            if object_type is not None:
+                base = format_type(object_type, self.options)
             else:
                 base = extract_type(name)
 
diff --git a/mypy/server/astdiff.py b/mypy/server/astdiff.py
index 1b0cc218ed16..16a0d882a8aa 100644
--- a/mypy/server/astdiff.py
+++ b/mypy/server/astdiff.py
@@ -460,6 +460,7 @@ def visit_callable_type(self, typ: CallableType) -> SnapshotItem:
             typ.is_type_obj(),
             typ.is_ellipsis_args,
             snapshot_types(typ.variables),
+            typ.is_bound,
         )
 
     def normalize_callable_variables(self, typ: CallableType) -> CallableType:
diff --git a/mypy/typeops.py b/mypy/typeops.py
index 3715081ae173..1a29054513a2 100644
--- a/mypy/typeops.py
+++ b/mypy/typeops.py
@@ -185,6 +185,7 @@ def type_object_type(info: TypeInfo, named_type: Callable[[str], Instance]) -> P
                     arg_kinds=[ARG_STAR, ARG_STAR2],
                     arg_names=["_args", "_kwds"],
                     ret_type=any_type,
+                    is_bound=True,
                     fallback=named_type("builtins.function"),
                 )
                 return class_callable(sig, info, fallback, None, is_new=False)
@@ -479,7 +480,7 @@ class B(A): pass
         arg_kinds=func.arg_kinds[1:],
         arg_names=func.arg_names[1:],
         variables=variables,
-        bound_args=[original_type],
+        is_bound=True,
     )
     return cast(F, res)
 
diff --git a/mypy/types.py b/mypy/types.py
index 41a958ae93cc..7f67c303a929 100644
--- a/mypy/types.py
+++ b/mypy/types.py
@@ -1597,6 +1597,9 @@ def with_name(self, name: str) -> FunctionLike:
     def get_name(self) -> str | None:
         pass
 
+    def bound(self) -> bool:
+        return bool(self.items) and self.items[0].is_bound
+
 
 class FormalArgument(NamedTuple):
     name: str | None
@@ -1826,8 +1829,7 @@ class CallableType(FunctionLike):
         # 'dict' and 'partial' for a `functools.partial` evaluation)
         "from_type_type",  # Was this callable generated by analyzing Type[...]
         # instantiation?
-        "bound_args",  # Bound type args, mostly unused but may be useful for
-        # tools that consume mypy ASTs
+        "is_bound",  # Is this a bound method?
         "def_extras",  # Information about original definition we want to serialize.
         # This is used for more detailed error messages.
         "type_guard",  # T, if -> TypeGuard[T] (ret_type is bool in this case).
@@ -1855,7 +1857,7 @@ def __init__(
         implicit: bool = False,
         special_sig: str | None = None,
         from_type_type: bool = False,
-        bound_args: Sequence[Type | None] = (),
+        is_bound: bool = False,
         def_extras: dict[str, Any] | None = None,
         type_guard: Type | None = None,
         type_is: Type | None = None,
@@ -1888,9 +1890,7 @@ def __init__(
         self.from_type_type = from_type_type
         self.from_concatenate = from_concatenate
         self.imprecise_arg_kinds = imprecise_arg_kinds
-        if not bound_args:
-            bound_args = ()
-        self.bound_args = bound_args
+        self.is_bound = is_bound
         if def_extras:
             self.def_extras = def_extras
         elif isinstance(definition, FuncDef):
@@ -1927,7 +1927,7 @@ def copy_modified(
         implicit: Bogus[bool] = _dummy,
         special_sig: Bogus[str | None] = _dummy,
         from_type_type: Bogus[bool] = _dummy,
-        bound_args: Bogus[list[Type | None]] = _dummy,
+        is_bound: Bogus[bool] = _dummy,
         def_extras: Bogus[dict[str, Any]] = _dummy,
         type_guard: Bogus[Type | None] = _dummy,
         type_is: Bogus[Type | None] = _dummy,
@@ -1952,7 +1952,7 @@ def copy_modified(
             implicit=implicit if implicit is not _dummy else self.implicit,
             special_sig=special_sig if special_sig is not _dummy else self.special_sig,
             from_type_type=from_type_type if from_type_type is not _dummy else self.from_type_type,
-            bound_args=bound_args if bound_args is not _dummy else self.bound_args,
+            is_bound=is_bound if is_bound is not _dummy else self.is_bound,
             def_extras=def_extras if def_extras is not _dummy else dict(self.def_extras),
             type_guard=type_guard if type_guard is not _dummy else self.type_guard,
             type_is=type_is if type_is is not _dummy else self.type_is,
@@ -2277,7 +2277,7 @@ def serialize(self) -> JsonDict:
             "variables": [v.serialize() for v in self.variables],
             "is_ellipsis_args": self.is_ellipsis_args,
             "implicit": self.implicit,
-            "bound_args": [(None if t is None else t.serialize()) for t in self.bound_args],
+            "is_bound": self.is_bound,
             "def_extras": dict(self.def_extras),
             "type_guard": self.type_guard.serialize() if self.type_guard is not None else None,
             "type_is": (self.type_is.serialize() if self.type_is is not None else None),
@@ -2300,7 +2300,7 @@ def deserialize(cls, data: JsonDict) -> CallableType:
             variables=[cast(TypeVarLikeType, deserialize_type(v)) for v in data["variables"]],
             is_ellipsis_args=data["is_ellipsis_args"],
             implicit=data["implicit"],
-            bound_args=[(None if t is None else deserialize_type(t)) for t in data["bound_args"]],
+            is_bound=data["is_bound"],
             def_extras=data["def_extras"],
             type_guard=(
                 deserialize_type(data["type_guard"]) if data["type_guard"] is not None else None
diff --git a/test-data/unit/check-classes.test b/test-data/unit/check-classes.test
index 59204cc31c43..036c8e21c310 100644
--- a/test-data/unit/check-classes.test
+++ b/test-data/unit/check-classes.test
@@ -4292,7 +4292,7 @@ int.__eq__(3, 4)
 [builtins fixtures/args.pyi]
 [out]
 main:33: error: Too few arguments for "__eq__" of "int"
-main:33: error: Unsupported operand types for == ("int" and "Type[int]")
+main:33: error: Unsupported operand types for == ("Type[int]" and "Type[int]")
 
 [case testDupBaseClasses]
 class A:
diff --git a/test-data/unit/check-functions.test b/test-data/unit/check-functions.test
index ac93c6c20354..35d76a65ccc3 100644
--- a/test-data/unit/check-functions.test
+++ b/test-data/unit/check-functions.test
@@ -3599,3 +3599,45 @@ class Bar(Foo):
 
     def foo(self, value: Union[int, str]) -> Union[int, str]:
         return super().foo(value)  # E: Call to abstract method "foo" of "Foo" with trivial body via super() is unsafe
+
+[case testBoundMethodsAssignedInClassBody]
+from typing import Callable
+
+class A:
+    def f(self, x: int) -> str:
+        pass
+    @classmethod
+    def g(cls, x: int) -> str:
+        pass
+    @staticmethod
+    def h(x: int) -> str:
+        pass
+    attr: Callable[[int], str]
+
+class C:
+    x1 = A.f
+    x2 = A.g
+    x3 = A().f
+    x4 = A().g
+    x5 = A.h
+    x6 = A().h
+    x7 = A().attr
+
+reveal_type(C.x1)  # N: Revealed type is "def (self: __main__.A, x: builtins.int) -> builtins.str"
+reveal_type(C.x2)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C.x3)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C.x4)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C.x5)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C.x6)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C.x7)  # N: Revealed type is "def (builtins.int) -> builtins.str"
+
+reveal_type(C().x1)  # E: Invalid self argument "C" to attribute function "x1" with type "Callable[[A, int], str]" \
+                     # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C().x2)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C().x3)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C().x4)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C().x5)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C().x6)  # N: Revealed type is "def (x: builtins.int) -> builtins.str"
+reveal_type(C().x7)  # E: Invalid self argument "C" to attribute function "x7" with type "Callable[[int], str]" \
+                     # N: Revealed type is "def () -> builtins.str"
+[builtins fixtures/classmethod.pyi]
diff --git a/test-data/unit/check-incremental.test b/test-data/unit/check-incremental.test
index 9d5902246ae5..fabd7e294d9a 100644
--- a/test-data/unit/check-incremental.test
+++ b/test-data/unit/check-incremental.test
@@ -6862,3 +6862,27 @@ if int():
 [out]
 [out2]
 main:6: error: Incompatible types in assignment (expression has type "str", variable has type "int")
+
+[case testMethodMakeBoundIncremental]
+from a import A
+a = A()
+a.f()
+[file a.py]
+class B:
+    def f(self, s: A) -> int: ...
+
+def f(s: A) -> int: ...
+
+class A:
+    f = f
+[file a.py.2]
+class B:
+    def f(self, s: A) -> int: ...
+
+def f(s: A) -> int: ...
+
+class A:
+    f = B().f
+[out]
+[out2]
+main:3: error: Too few arguments
diff --git a/test-data/unit/fine-grained.test b/test-data/unit/fine-grained.test
index df244b3135e9..eb07f37a8671 100644
--- a/test-data/unit/fine-grained.test
+++ b/test-data/unit/fine-grained.test
@@ -11217,3 +11217,27 @@ class A:
 [out]
 ==
 main:3: error: Property "f" defined in "A" is read-only
+
+[case testMethodMakeBoundFineGrained]
+from a import A
+a = A()
+a.f()
+[file a.py]
+class B:
+    def f(self, s: A) -> int: ...
+
+def f(s: A) -> int: ...
+
+class A:
+    f = f
+[file a.py.2]
+class B:
+    def f(self, s: A) -> int: ...
+
+def f(s: A) -> int: ...
+
+class A:
+    f = B().f
+[out]
+==
+main:3: error: Too few arguments

From 9fb5ff66c51bd971d7a6b1260cc0ec9f1b82cc06 Mon Sep 17 00:00:00 2001
From: Ivan Levkivskyi <levkivskyi@gmail.com>
Date: Sat, 7 Jun 2025 23:59:23 +0100
Subject: [PATCH 18/20] Fix properties with setters after deleters (#19248)

Fixes https://github.com/python/mypy/issues/19224

Note we must add an additional attribute on `OverloadedFuncDef` since
decorator expressions are not serialized.
---
 mypy/checker.py                   | 10 ++++------
 mypy/checkmember.py               |  4 ++--
 mypy/nodes.py                     | 24 +++++++++++++++++++++++-
 mypy/semanal.py                   |  1 +
 test-data/unit/check-classes.test | 20 ++++++++++++++++++++
 5 files changed, 50 insertions(+), 9 deletions(-)

diff --git a/mypy/checker.py b/mypy/checker.py
index 5a5d19cc0006..dc3d670dd73e 100644
--- a/mypy/checker.py
+++ b/mypy/checker.py
@@ -675,11 +675,9 @@ def _visit_overloaded_func_def(self, defn: OverloadedFuncDef) -> None:
             assert isinstance(defn.items[0], Decorator)
             self.visit_decorator(defn.items[0])
             if defn.items[0].var.is_settable_property:
-                # TODO: here and elsewhere we assume setter immediately follows getter.
-                assert isinstance(defn.items[1], Decorator)
                 # Perform a reduced visit just to infer the actual setter type.
-                self.visit_decorator_inner(defn.items[1], skip_first_item=True)
-                setter_type = defn.items[1].var.type
+                self.visit_decorator_inner(defn.setter, skip_first_item=True)
+                setter_type = defn.setter.var.type
                 # Check if the setter can accept two positional arguments.
                 any_type = AnyType(TypeOfAny.special_form)
                 fallback_setter_type = CallableType(
@@ -690,7 +688,7 @@ def _visit_overloaded_func_def(self, defn: OverloadedFuncDef) -> None:
                     fallback=self.named_type("builtins.function"),
                 )
                 if setter_type and not is_subtype(setter_type, fallback_setter_type):
-                    self.fail("Invalid property setter signature", defn.items[1].func)
+                    self.fail("Invalid property setter signature", defn.setter.func)
                 setter_type = self.extract_callable_type(setter_type, defn)
                 if not isinstance(setter_type, CallableType) or len(setter_type.arg_types) != 2:
                     # TODO: keep precise type for callables with tricky but valid signatures.
@@ -2149,7 +2147,7 @@ def check_setter_type_override(self, defn: OverloadedFuncDef, base: TypeInfo) ->
         assert typ is not None and original_type is not None
 
         if not is_subtype(original_type, typ):
-            self.msg.incompatible_setter_override(defn.items[1], typ, original_type, base)
+            self.msg.incompatible_setter_override(defn.setter, typ, original_type, base)
 
     def check_method_override_for_base_with_name(
         self, defn: FuncDef | OverloadedFuncDef | Decorator, name: str, base: TypeInfo
diff --git a/mypy/checkmember.py b/mypy/checkmember.py
index ea76a6cc304f..596eccab09a7 100644
--- a/mypy/checkmember.py
+++ b/mypy/checkmember.py
@@ -341,8 +341,8 @@ def analyze_instance_member_access(
             assert isinstance(method, OverloadedFuncDef)
             getter = method.items[0]
             assert isinstance(getter, Decorator)
-            if mx.is_lvalue and (len(items := method.items) > 1):
-                mx.chk.warn_deprecated(items[1], mx.context)
+            if mx.is_lvalue and getter.var.is_settable_property:
+                mx.chk.warn_deprecated(method.setter, mx.context)
             return analyze_var(name, getter.var, typ, mx)
 
         if mx.is_lvalue and not mx.suppress_errors:
diff --git a/mypy/nodes.py b/mypy/nodes.py
index 9a9403722a16..0d4c96ac5793 100644
--- a/mypy/nodes.py
+++ b/mypy/nodes.py
@@ -550,12 +550,20 @@ class OverloadedFuncDef(FuncBase, SymbolNode, Statement):
     Overloaded variants must be consecutive in the source file.
     """
 
-    __slots__ = ("items", "unanalyzed_items", "impl", "deprecated", "_is_trivial_self")
+    __slots__ = (
+        "items",
+        "unanalyzed_items",
+        "impl",
+        "deprecated",
+        "setter_index",
+        "_is_trivial_self",
+    )
 
     items: list[OverloadPart]
     unanalyzed_items: list[OverloadPart]
     impl: OverloadPart | None
     deprecated: str | None
+    setter_index: int | None
 
     def __init__(self, items: list[OverloadPart]) -> None:
         super().__init__()
@@ -563,6 +571,7 @@ def __init__(self, items: list[OverloadPart]) -> None:
         self.unanalyzed_items = items.copy()
         self.impl = None
         self.deprecated = None
+        self.setter_index = None
         self._is_trivial_self: bool | None = None
         if items:
             # TODO: figure out how to reliably set end position (we don't know the impl here).
@@ -598,6 +607,17 @@ def is_trivial_self(self) -> bool:
         self._is_trivial_self = True
         return True
 
+    @property
+    def setter(self) -> Decorator:
+        # Do some consistency checks first.
+        first_item = self.items[0]
+        assert isinstance(first_item, Decorator)
+        assert first_item.var.is_settable_property
+        assert self.setter_index is not None
+        item = self.items[self.setter_index]
+        assert isinstance(item, Decorator)
+        return item
+
     def accept(self, visitor: StatementVisitor[T]) -> T:
         return visitor.visit_overloaded_func_def(self)
 
@@ -610,6 +630,7 @@ def serialize(self) -> JsonDict:
             "impl": None if self.impl is None else self.impl.serialize(),
             "flags": get_flags(self, FUNCBASE_FLAGS),
             "deprecated": self.deprecated,
+            "setter_index": self.setter_index,
         }
 
     @classmethod
@@ -630,6 +651,7 @@ def deserialize(cls, data: JsonDict) -> OverloadedFuncDef:
         res._fullname = data["fullname"]
         set_flags(res, data["flags"])
         res.deprecated = data["deprecated"]
+        res.setter_index = data["setter_index"]
         # NOTE: res.info will be set in the fixup phase.
         return res
 
diff --git a/mypy/semanal.py b/mypy/semanal.py
index 89bb5ab97c2a..bc64e7e7ca53 100644
--- a/mypy/semanal.py
+++ b/mypy/semanal.py
@@ -1558,6 +1558,7 @@ def analyze_property_with_multi_part_definition(
                             )
                             assert isinstance(setter_func_type, CallableType)
                             bare_setter_type = setter_func_type
+                            defn.setter_index = i + 1
                         if first_node.name == "deleter":
                             item.func.abstract_status = first_item.func.abstract_status
                         for other_node in item.decorators[1:]:
diff --git a/test-data/unit/check-classes.test b/test-data/unit/check-classes.test
index 036c8e21c310..10e15139218f 100644
--- a/test-data/unit/check-classes.test
+++ b/test-data/unit/check-classes.test
@@ -8739,3 +8739,23 @@ class NoopPowerResource:
     def hardware_type(self) -> None:  # E: Invalid property setter signature
         self.hardware_type = None  # Note: intentionally recursive
 [builtins fixtures/property.pyi]
+
+[case testPropertyAllowsDeleterBeforeSetter]
+class C:
+    @property
+    def foo(self) -> str: ...
+    @foo.deleter
+    def foo(self) -> None: ...
+    @foo.setter
+    def foo(self, val: int) -> None: ...
+
+    @property
+    def bar(self) -> int: ...
+    @bar.deleter
+    def bar(self) -> None: ...
+    @bar.setter
+    def bar(self, value: int, val: int) -> None: ...  # E: Invalid property setter signature
+
+C().foo = "no"  # E: Incompatible types in assignment (expression has type "str", variable has type "int")
+C().bar = "fine"
+[builtins fixtures/property.pyi]

From e253eded9c887630f3f5404c4b9f73f13570476a Mon Sep 17 00:00:00 2001
From: A5rocks <git@helvetica.moe>
Date: Wed, 11 Jun 2025 13:57:31 +0900
Subject: [PATCH 19/20] Single underscore is not a sunder (#19273)

Fixes https://github.com/python/mypy/issues/19271.
---
 mypy/util.py                   |  2 +-
 test-data/unit/check-enum.test | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/mypy/util.py b/mypy/util.py
index d3f49f74bbae..d7ff2a367fa2 100644
--- a/mypy/util.py
+++ b/mypy/util.py
@@ -66,7 +66,7 @@ def is_dunder(name: str, exclude_special: bool = False) -> bool:
 
 
 def is_sunder(name: str) -> bool:
-    return not is_dunder(name) and name.startswith("_") and name.endswith("_")
+    return not is_dunder(name) and name.startswith("_") and name.endswith("_") and name != "_"
 
 
 def split_module_names(mod_name: str) -> list[str]:
diff --git a/test-data/unit/check-enum.test b/test-data/unit/check-enum.test
index cc9048db18dc..3001bc9a69cb 100644
--- a/test-data/unit/check-enum.test
+++ b/test-data/unit/check-enum.test
@@ -2524,3 +2524,18 @@ class Base:
         self.o = Enum("o", names)  # E: Enum type as attribute is not supported \
                                    # E: Second argument of Enum() must be string, tuple, list or dict literal for mypy to determine Enum members
 [builtins fixtures/tuple.pyi]
+
+[case testSingleUnderscoreNameEnumMember]
+# flags: --warn-unreachable
+
+# https://github.com/python/mypy/issues/19271
+from enum import Enum
+
+class Things(Enum):
+    _ = "under score"
+
+def check(thing: Things) -> None:
+    if thing is Things._:
+        return None
+    return None  # E: Statement is unreachable
+[builtins fixtures/enum.pyi]

From 68b8fa097d080c92d30a429bc74de8acd56caf85 Mon Sep 17 00:00:00 2001
From: Jukka Lehtosalo <jukka.lehtosalo@iki.fi>
Date: Wed, 11 Jun 2025 16:25:56 +0100
Subject: [PATCH 20/20] Bump version to 1.16.1

---
 mypy/version.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mypy/version.py b/mypy/version.py
index d2d42a386dec..a003b2b70558 100644
--- a/mypy/version.py
+++ b/mypy/version.py
@@ -8,7 +8,7 @@
 # - Release versions have the form "1.2.3".
 # - Dev versions have the form "1.2.3+dev" (PLUS sign to conform to PEP 440).
 # - Before 1.0 we had the form "0.NNN".
-__version__ = "1.16.1+dev"
+__version__ = "1.16.1"
 base_version = __version__
 
 mypy_dir = os.path.abspath(os.path.dirname(os.path.dirname(__file__)))