Update node checks to be more type specific and rename typ to argtyp

mypy/checkexpr.py

@@ -551,31 +551,33 @@ def visit_call_expr_inner(self, e: CallExpr, allow_none_return: bool = False) ->
         ):
             # Special hanlding for get_args(), returns a typed tuple
             # with the type set by the input
-            typ = None
+            argtyp = None
             if isinstance(e.args[0], IndexExpr):
                 self.accept(e.args[0].index)
-                typ = self.chk.lookup_type(e.args[0].index)
-            else:
+                argtyp = self.chk.lookup_type(e.args[0].index)
+            elif isinstance(e.args[0], NameExpr):
                 try:
                     node = self.chk.lookup_qualified(e.args[0].name)
                     if node:
                         if isinstance(node.node, TypeAlias):
                             # Resolve type
-                            typ = get_proper_type(node.node.target)
-                        else:
-                            typ = node.node.type
+                            argtyp = node.node.target
+                        elif isinstance(node.node, Var):
+                            argtyp = node.node.type
                 except KeyError:
                     # Undefined names should already be reported in semantic analysis.
                     pass
+            if argtyp is not None:
+                argtyp = get_proper_type(argtyp)
             if (
-                typ is not None
-                and isinstance(typ, UnionType)
-                and all(isinstance(t, LiteralType) for t in typ.items)
+                argtyp is not None
+                and isinstance(argtyp, UnionType)
+                and all(isinstance(get_proper_type(t), LiteralType) for t in argtyp.items)
             ):
                 # Returning strings is defined but order isn't so
                 # we need to return type * len of the union
                 return TupleType(
-                    [typ] * len(typ.items), fallback=self.named_type("builtins.tuple")
+                    [argtyp] * len(argtyp.items), fallback=self.named_type("builtins.tuple")
                 )
             else:
                 # Fall back to what we did anyway (Tuple[Any])