refactor: compact and optimize infer_overload_return_type while preserving behavior and comments

Author: victorletichevsky

mypy/checkexpr.py

@@ -2876,69 +2876,55 @@ def infer_overload_return_type(
 
         Assumes all of the given targets have argument counts compatible with the caller.
         """
-
         matches: list[CallableType] = []
         return_types: list[Type] = []
         inferred_types: list[Type] = []
-        args_contain_any = any(map(has_any_type, arg_types))
         type_maps: list[dict[Expression, Type]] = []
+        args_contain_any = any(map(has_any_type, arg_types))
 
         for typ in plausible_targets:
             assert self.msg is self.chk.msg
-            with self.msg.filter_errors() as w:
-                with self.chk.local_type_map() as m:
-                    ret_type, infer_type = self.check_call(
-                        callee=typ,
-                        args=args,
-                        arg_kinds=arg_kinds,
-                        arg_names=arg_names,
-                        context=context,
-                        callable_name=callable_name,
-                        object_type=object_type,
-                    )
-            is_match = not w.has_new_errors()
-            if is_match:
-                # Return early if possible; otherwise record info, so we can
-                # check for ambiguity due to 'Any' below.
-                if not args_contain_any:
-                    self.chk.store_types(m)
-                    return ret_type, infer_type
-                p_infer_type = get_proper_type(infer_type)
-                if isinstance(p_infer_type, CallableType):
-                    # Prefer inferred types if possible, this will avoid false triggers for
-                    # Any-ambiguity caused by arguments with Any passed to generic overloads.
-                    matches.append(p_infer_type)
-                else:
-                    matches.append(typ)
-                return_types.append(ret_type)
-                inferred_types.append(infer_type)
-                type_maps.append(m)
+            with self.msg.filter_errors() as w, self.chk.local_type_map() as m:
+                ret_type, infer_type = self.check_call(
+                    callee=typ, args=args, arg_kinds=arg_kinds, arg_names=arg_names,
+                    context=context, callable_name=callable_name, object_type=object_type)
+            if w.has_new_errors(): continue
+
+            # Return early if possible; otherwise record info, so we can
+            # check for ambiguity due to 'Any' below.
+            if not args_contain_any:
+                self.chk.store_types(m)
+                return ret_type, infer_type
+
+            # Prefer inferred types if possible, this will avoid false triggers for
+            # Any-ambiguity caused by arguments with Any passed to generic overloads.
+            p = get_proper_type(infer_type)
+            matches.append(p if isinstance(p, CallableType) else typ)
+            return_types.append(ret_type)
+            inferred_types.append(infer_type)
+            type_maps.append(m)
 
         if not matches:
             return None
-        elif any_causes_overload_ambiguity(matches, return_types, arg_types, arg_kinds, arg_names):
-            # An argument of type or containing the type 'Any' caused ambiguity.
-            # We try returning a precise type if we can. If not, we give up and just return 'Any'.
+
+        # An argument of type or containing the type 'Any' caused ambiguity.
+        # We try returning a precise type if we can. If not, we give up and just return 'Any'.
+        if any_causes_overload_ambiguity(matches, return_types, arg_types, arg_kinds, arg_names):
             if all_same_types(return_types):
                 self.chk.store_types(type_maps[0])
                 return return_types[0], inferred_types[0]
-            elif all_same_types([erase_type(typ) for typ in return_types]):
+            erased = [erase_type(t) for t in return_types]
+            if all_same_types(cast(list[Type], erased)):
                 self.chk.store_types(type_maps[0])
                 return erase_type(return_types[0]), erase_type(inferred_types[0])
-            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])
-            return return_types[0], 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)
+
+        # Success! No ambiguity; return the first match.
+        self.chk.store_types(type_maps[0])
+        return return_types[0], inferred_types[0]
 
     def overload_erased_call_targets(
         self,