.

mypy/typeanal.py

@@ -1455,7 +1455,8 @@ def analyze_callable_args(
                 if self.defining_alias and self.has_type_params:
                     tvar_likes = self.find_type_var_likes(arg)
                     for name, tvar_expr in tvar_likes:
-                        if (name, tvar_expr) not in self.allowed_alias_tvars:
+                        tvar_def = self.tvar_scope.get_binding(name)
+                        if tvar_def is None or tvar_def not in self.allowed_alias_tvars:
                             self.fail(
                                 f'Type variable "{name}" is not included in type_params',
                                 arglist,

test-data/unit/check-type-aliases.test

@@ -1115,9 +1115,13 @@ reveal_type(xi)  # N: Revealed type is "builtins.dict[builtins.int, builtins.str
 
 VariadicAlias1 = TypeAliasType("VariadicAlias1", Tuple[Unpack[Ts]], type_params=(Ts,))
 VariadicAlias2 = TypeAliasType("VariadicAlias2", Tuple[Unpack[Ts], K], type_params=(Ts, K))
+VariadicAlias3 = TypeAliasType("VariadicAlias3", Callable[[Unpack[Ts]], int], type_params=(Ts,))
 xv: VariadicAlias1[int, str] = (1, 'a')
 yv: VariadicAlias1[str, int] = (1, 'a')  # E: Incompatible types in assignment (expression has type "Tuple[int, str]", variable has type "Tuple[str, int]")
 zv: VariadicAlias2[int, str] = (1, 'a')
+def int_in_int_out(x: int) -> int: return x
+wv: VariadicAlias3[int] = int_in_int_out
+reveal_type(wv)  # N: Revealed type is "def (builtins.int) -> builtins.int"
 
 ParamAlias = TypeAliasType("ParamAlias", Callable[P, int], type_params=(P,))
 def f(x: str, y: float) -> int: return 1