Implement closed support in serialization

Author: alicederyn

mypy/types.py

@@ -3020,17 +3020,17 @@ def serialize(self) -> JsonDict:
             "required_keys": sorted(self.required_keys),
             "readonly_keys": sorted(self.readonly_keys),
             "fallback": self.fallback.serialize(),
+            "is_closed": self.is_closed,
         }
 
     @classmethod
     def deserialize(cls, data: JsonDict) -> TypedDictType:
         assert data[".class"] == "TypedDictType"
-        # TODO: round-trip is_closed
         return TypedDictType(
             {n: deserialize_type(t) for (n, t) in data["items"]},
             set(data["required_keys"]),
             set(data["readonly_keys"]),
-            False,
+            bool(data["is_closed"]),
             Instance.deserialize(data["fallback"]),
         )
 
@@ -3040,18 +3040,18 @@ def write(self, data: WriteBuffer) -> None:
         write_type_map(data, self.items)
         write_str_list(data, sorted(self.required_keys))
         write_str_list(data, sorted(self.readonly_keys))
+        write_bool(data, self.is_closed)
         write_tag(data, END_TAG)
 
     @classmethod
     def read(cls, data: ReadBuffer) -> TypedDictType:
         assert read_tag(data) == INSTANCE
         fallback = Instance.read(data)
-        # TODO: round-trip is_closed
         ret = TypedDictType(
             read_type_map(data),
             set(read_str_list(data)),
             set(read_str_list(data)),
-            False,
+            read_bool(data),
             fallback,
         )
         assert read_tag(data) == END_TAG

test-data/unit/check-serialize.test

@@ -1088,6 +1088,20 @@ main:2: note: Revealed type is "TypedDict('m.D', {'x'?: builtins.int, 'y'?: buil
 [out2]
 main:2: note: Revealed type is "TypedDict('m.D', {'x'?: builtins.int, 'y'?: builtins.str})"
 
+[case testSerializeClosedTotalTypedDict]
+from m import d
+reveal_type(d)
+[file m.py]
+from typing import TypedDict
+D = TypedDict('D', {'x': int, 'y': str}, closed=True)
+d: D
+[builtins fixtures/dict.pyi]
+[typing fixtures/typing-typeddict.pyi]
+[out1]
+main:2: note: Revealed type is "TypedDict('m.D', {'x': builtins.int, 'y': builtins.str}, closed=True)"
+[out2]
+main:2: note: Revealed type is "TypedDict('m.D', {'x': builtins.int, 'y': builtins.str}, closed=True)"
+
 --
 -- Modules
 --