Add constants for Concatenate and Unpack type names (#18553)

Author: cdce8p

mypy/semanal.py

@@ -268,6 +268,7 @@
     TYPE_CHECK_ONLY_NAMES,
     TYPE_VAR_LIKE_NAMES,
     TYPED_NAMEDTUPLE_NAMES,
+    UNPACK_TYPE_NAMES,
     AnyType,
     CallableType,
     FunctionLike,
@@ -2286,7 +2287,7 @@ def analyze_unbound_tvar(self, t: Type) -> tuple[str, TypeVarLikeExpr] | None:
             return self.analyze_unbound_tvar_impl(t.type, is_unpacked=True)
         if isinstance(t, UnboundType):
             sym = self.lookup_qualified(t.name, t)
-            if sym and sym.fullname in ("typing.Unpack", "typing_extensions.Unpack"):
+            if sym and sym.fullname in UNPACK_TYPE_NAMES:
                 inner_t = t.args[0]
                 if isinstance(inner_t, UnboundType):
                     return self.analyze_unbound_tvar_impl(inner_t, is_unpacked=True)
@@ -4171,7 +4172,7 @@ def analyze_type_alias_type_params(
                         base,
                         code=codes.TYPE_VAR,
                     )
-                    if sym and sym.fullname in ("typing.Unpack", "typing_extensions.Unpack"):
+                    if sym and sym.fullname in UNPACK_TYPE_NAMES:
                         self.note(
                             "Don't Unpack type variables in type_params", base, code=codes.TYPE_VAR
                         )

mypy/stubgen.py

@@ -145,6 +145,7 @@
     DATACLASS_TRANSFORM_NAMES,
     OVERLOAD_NAMES,
     TPDICT_NAMES,
+    TYPE_VAR_LIKE_NAMES,
     TYPED_NAMEDTUPLE_NAMES,
     AnyType,
     CallableType,
@@ -1090,14 +1091,7 @@ def is_alias_expression(self, expr: Expression, top_level: bool = True) -> bool:
         or module alias.
         """
         # Assignment of TypeVar(...)  and other typevar-likes are passed through
-        if isinstance(expr, CallExpr) and self.get_fullname(expr.callee) in (
-            "typing.TypeVar",
-            "typing_extensions.TypeVar",
-            "typing.ParamSpec",
-            "typing_extensions.ParamSpec",
-            "typing.TypeVarTuple",
-            "typing_extensions.TypeVarTuple",
-        ):
+        if isinstance(expr, CallExpr) and self.get_fullname(expr.callee) in TYPE_VAR_LIKE_NAMES:
             return True
         elif isinstance(expr, EllipsisExpr):
             return not top_level

mypy/typeanal.py

@@ -62,10 +62,12 @@
 from mypy.types import (
     ANNOTATED_TYPE_NAMES,
     ANY_STRATEGY,
+    CONCATENATE_TYPE_NAMES,
     FINAL_TYPE_NAMES,
     LITERAL_TYPE_NAMES,
     NEVER_NAMES,
     TYPE_ALIAS_NAMES,
+    UNPACK_TYPE_NAMES,
     AnyType,
     BoolTypeQuery,
     CallableArgument,
@@ -525,7 +527,7 @@ def visit_unbound_type_nonoptional(self, t: UnboundType, defining_literal: bool)
             elif node.fullname in TYPE_ALIAS_NAMES:
                 return AnyType(TypeOfAny.special_form)
             # Concatenate is an operator, no need for a proper type
-            elif node.fullname in ("typing_extensions.Concatenate", "typing.Concatenate"):
+            elif node.fullname in CONCATENATE_TYPE_NAMES:
                 # We check the return type further up the stack for valid use locations
                 return self.apply_concatenate_operator(t)
             else:
@@ -779,7 +781,7 @@ def try_analyze_special_unbound_type(self, t: UnboundType, fullname: str) -> Typ
         ):
             # In most contexts, TypeGuard[...] acts as an alias for bool (ignoring its args)
             return self.named_type("builtins.bool")
-        elif fullname in ("typing.Unpack", "typing_extensions.Unpack"):
+        elif fullname in UNPACK_TYPE_NAMES:
             if len(t.args) != 1:
                 self.fail("Unpack[...] requires exactly one type argument", t)
                 return AnyType(TypeOfAny.from_error)
@@ -1503,7 +1505,7 @@ def analyze_callable_args_for_concatenate(
             return None
         if sym.node is None:
             return None
-        if sym.node.fullname not in ("typing_extensions.Concatenate", "typing.Concatenate"):
+        if sym.node.fullname not in CONCATENATE_TYPE_NAMES:
             return None
 
         tvar_def = self.anal_type(callable_args, allow_param_spec=True)
@@ -1652,7 +1654,7 @@ def analyze_callable_args(
                         return None
             elif (
                 isinstance(arg, UnboundType)
-                and self.refers_to_full_names(arg, ("typing_extensions.Unpack", "typing.Unpack"))
+                and self.refers_to_full_names(arg, UNPACK_TYPE_NAMES)
                 or isinstance(arg, UnpackType)
             ):
                 if seen_unpack:

mypy/types.py

@@ -130,6 +130,12 @@
 # Supported Annotated type names.
 ANNOTATED_TYPE_NAMES: Final = ("typing.Annotated", "typing_extensions.Annotated")
 
+# Supported Concatenate type names.
+CONCATENATE_TYPE_NAMES: Final = ("typing.Concatenate", "typing_extensions.Concatenate")
+
+# Supported Unpack type names.
+UNPACK_TYPE_NAMES: Final = ("typing.Unpack", "typing_extensions.Unpack")
+
 # Supported @deprecated type names
 DEPRECATED_TYPE_NAMES: Final = ("warnings.deprecated", "typing_extensions.deprecated")