From b92de51c2f94ed0f9fe55b6aba86cba51737ad20 Mon Sep 17 00:00:00 2001
From: tjhub1983 <2368494411@qq.com>
Date: Sat, 2 May 2026 17:51:52 +0800
Subject: [PATCH 1/3] Fix: allow instantiating type[None] and type(None)

Python 3 allows calling NoneType() and type(None)():
    >>> NoneType()
    None
    >>> type(None)()
    None

But mypy raised an "unsupported_type_type" error in analyze_type_type_callee
when encountering a Type[None] callee. Fixed by adding isinstance(item, NoneType)
branch that returns a zero-argument CallableType returning NoneType.

Fixes python/mypy#19660.
---
 mypy/checkexpr.py | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/mypy/checkexpr.py b/mypy/checkexpr.py
index c9296bd5e875d..7aff11b8810ff 100644
--- a/mypy/checkexpr.py
+++ b/mypy/checkexpr.py
@@ -1934,6 +1934,15 @@ def analyze_type_type_callee(self, item: ProperType, context: Context) -> Type:
         # We support Type of namedtuples but not of tuples in general
         if isinstance(item, TupleType) and tuple_fallback(item).type.fullname != "builtins.tuple":
             return self.analyze_type_type_callee(tuple_fallback(item), context)
+        if isinstance(item, NoneType):
+            # type(None)() and NoneType() are valid in Python 3
+            return CallableType(
+                arg_types=[],
+                arg_kinds=[],
+                arg_names=[],
+                ret_type=item,
+                fallback=None,
+            )
         if isinstance(item, TypedDictType):
             return self.typeddict_callable_from_context(item)
 

From 8cd10ea21ab2b2a5ab33801fd3a996ba5fe646a2 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Sat, 2 May 2026 10:09:14 +0000
Subject: [PATCH 2/3] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 mypy/checkexpr.py | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/mypy/checkexpr.py b/mypy/checkexpr.py
index 7aff11b8810ff..7b4214b090c0d 100644
--- a/mypy/checkexpr.py
+++ b/mypy/checkexpr.py
@@ -1937,11 +1937,7 @@ def analyze_type_type_callee(self, item: ProperType, context: Context) -> Type:
         if isinstance(item, NoneType):
             # type(None)() and NoneType() are valid in Python 3
             return CallableType(
-                arg_types=[],
-                arg_kinds=[],
-                arg_names=[],
-                ret_type=item,
-                fallback=None,
+                arg_types=[], arg_kinds=[], arg_names=[], ret_type=item, fallback=None
             )
         if isinstance(item, TypedDictType):
             return self.typeddict_callable_from_context(item)

From c062d615cb0b6d0ca85035afcf36c3f3539b3a5d Mon Sep 17 00:00:00 2001
From: tjhub1983 <2368494411@qq.com>
Date: Sat, 2 May 2026 21:14:19 +0800
Subject: [PATCH 3/3] Fix: allow setting `output` in mypy.ini / mypy.toml

`output` in Options defaults to None (meaning unset). The config parser
skips options when getattr(template, key, None) returns None, so
`output = json` in mypy.ini was silently ignored.

Fixed by adding `"output": str` to both ini_config_types and
toml_config_types, so the option is recognized and properly set.

Fixes python/mypy#21376.
---
 mypy/config_parser.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mypy/config_parser.py b/mypy/config_parser.py
index 97fa01b8dd215..5fe976fc77161 100644
--- a/mypy/config_parser.py
+++ b/mypy/config_parser.py
@@ -207,6 +207,7 @@ def split_commas(value: str) -> list[str]:
     "exclude": lambda s: [s.strip()],
     "packages": try_split,
     "modules": try_split,
+    "output": str,
 }
 
 # Reuse the ini_config_types and overwrite the diff
@@ -229,6 +230,7 @@ def split_commas(value: str) -> list[str]:
         "exclude": str_or_array_as_list,
         "packages": try_split,
         "modules": try_split,
+        "output": str,
     }
 )