use the thrift-py3 __Type enum in unions

Summary:
The `Union.type` and `Union.Type` api was left partially unimplemented in the hopes we could easily unify thrift-py3 and thrift-python enums on trunk.

Since that appears to be a non-trivial lift, add a test documenting current behavior and update inplace-migrate to have self-consistent behavior that matches py3 trunk.

Reviewed By: createdbysk

Differential Revision: D73063538

fbshipit-source-id: a8774af8909938d685712075505d366bcebd54dc

Author: ahilger

Diff for: thrift/compiler/generate/templates/py3/types_inplace_FBTHRIFT_ONLY_DO_NOT_USE.py.mustache

@@ -80,6 +80,10 @@ __all__.append("{{enum:name}}")
 
 {{> inplace/union_enum_py }}
 
+
+{{! this is a dumb hack due to dunder class mangling rules}}
+_{{struct:name}}__{{struct:name}}Type = __{{struct:name}}Type
+
 {{#program:inplace_migrate?}}
 __all__.append("__{{struct:name}}Type")
 
@@ -120,7 +124,7 @@ class {{struct:name}}({{> types/python_struct_class }}):
     _fbthrift_allow_inheritance_DO_NOT_USE = True
     {{/struct:allow_inheritance?}}
     {{#struct:union?}}
-    Type = _fbthrift_python_types.{{struct:name}}.Type
+    Type = __{{struct:name}}Type
     {{/struct:union?}}
     _fbthrift__inner : _fbthrift_python_types.{{struct:name}}
     {{#struct:fields_and_mixin_fields}}
@@ -231,7 +235,9 @@ class {{struct:name}}({{> types/python_struct_class }}):
     {{#struct:union?}}
     @_python__property
     def type(self) -> _fbthrift_python_types.{{struct:name}}.Type:
-        return self._fbthrift__inner.type
+        if self._fbthrift_inner__type is None:
+            self._fbthrift_inner__type = self.Type(self._fbthrift__inner.type.value)
+        return self._fbthrift_inner__type
 
     @_python__property
     def value(self) -> {{> inplace/union_value_type }}:

Diff for: thrift/compiler/test/fixtures/basic/out/py3_inplace/gen-py3/test/fixtures/basic/module/types_inplace_FBTHRIFT_ONLY_DO_NOT_USE.py

@@ -60,6 +60,9 @@ class __MyUnionType(enum.Enum):
 
     __module__ = _fbthrift__module_name__
     __slots__ = ()
+
+_MyUnion__MyUnionType = __MyUnionType
+
 __all__.append("__MyUnionType")
 
 
@@ -69,6 +72,9 @@ class __UnionToBeRenamedType(enum.Enum):
 
     __module__ = _fbthrift__module_name__
     __slots__ = ()
+
+_UnionToBeRenamed__UnionToBeRenamedType = __UnionToBeRenamedType
+
 __all__.append("__UnionToBeRenamedType")
 
 
@@ -740,7 +746,7 @@ class MyUnion(thrift.py3.types.Union):
         "myDataItem",
         "floatSet",
     )
-    Type = _fbthrift_python_types.MyUnion.Type
+    Type = __MyUnionType
     _fbthrift__inner : _fbthrift_python_types.MyUnion
     _fbthrift_inner__myStruct : MyStruct | None
     _fbthrift_inner__myDataItem : MyDataItem | None
@@ -828,7 +834,9 @@ def floatSet(self) -> _typing.AbstractSet[float]:
 
     @_python__property
     def type(self) -> _fbthrift_python_types.MyUnion.Type:
-        return self._fbthrift__inner.type
+        if self._fbthrift_inner__type is None:
+            self._fbthrift_inner__type = self.Type(self._fbthrift__inner.type.value)
+        return self._fbthrift_inner__type
 
     @_python__property
     def value(self) -> MyEnum | MyStruct | MyDataItem | _typing.AbstractSet[float] | None:
@@ -1256,7 +1264,7 @@ class UnionToBeRenamed(thrift.py3.types.Union):
     _FBTHRIFT__FIELD_NAMES = (
         "reserved_field",
     )
-    Type = _fbthrift_python_types.UnionToBeRenamed.Type
+    Type = __UnionToBeRenamedType
     _fbthrift__inner : _fbthrift_python_types.UnionToBeRenamed
     _fbthrift_inner__type: Type
     _fbthrift_inner__value: int | None
@@ -1308,7 +1316,9 @@ def reserved_field(self) -> int:
 
     @_python__property
     def type(self) -> _fbthrift_python_types.UnionToBeRenamed.Type:
-        return self._fbthrift__inner.type
+        if self._fbthrift_inner__type is None:
+            self._fbthrift_inner__type = self.Type(self._fbthrift__inner.type.value)
+        return self._fbthrift_inner__type
 
     @_python__property
     def value(self) -> int | None:

Diff for: thrift/compiler/test/fixtures/constants/out/py3_inplace/gen-py3/module/types_inplace_FBTHRIFT_ONLY_DO_NOT_USE.py

@@ -63,6 +63,9 @@ class __union1Type(enum.Enum):
 
     __module__ = _fbthrift__module_name__
     __slots__ = ()
+
+_union1__union1Type = __union1Type
+
 __all__.append("__union1Type")
 
 
@@ -75,6 +78,9 @@ class __union2Type(enum.Enum):
 
     __module__ = _fbthrift__module_name__
     __slots__ = ()
+
+_union2__union2Type = __union2Type
+
 __all__.append("__union2Type")
 
 
@@ -1478,7 +1484,7 @@ class union1(thrift.py3.types.Union):
         "i",
         "d",
     )
-    Type = _fbthrift_python_types.union1.Type
+    Type = __union1Type
     _fbthrift__inner : _fbthrift_python_types.union1
     _fbthrift_inner__type: Type
     _fbthrift_inner__value: int | float | None
@@ -1534,7 +1540,9 @@ def d(self) -> float:
 
     @_python__property
     def type(self) -> _fbthrift_python_types.union1.Type:
-        return self._fbthrift__inner.type
+        if self._fbthrift_inner__type is None:
+            self._fbthrift_inner__type = self.Type(self._fbthrift__inner.type.value)
+        return self._fbthrift_inner__type
 
     @_python__property
     def value(self) -> int | float | None:
@@ -1617,7 +1625,7 @@ class union2(thrift.py3.types.Union):
         "s",
         "u",
     )
-    Type = _fbthrift_python_types.union2.Type
+    Type = __union2Type
     _fbthrift__inner : _fbthrift_python_types.union2
     _fbthrift_inner__s : struct1 | None
     _fbthrift_inner__u : union1 | None
@@ -1697,7 +1705,9 @@ def u(self) -> union1:
 
     @_python__property
     def type(self) -> _fbthrift_python_types.union2.Type:
-        return self._fbthrift__inner.type
+        if self._fbthrift_inner__type is None:
+            self._fbthrift_inner__type = self.Type(self._fbthrift__inner.type.value)
+        return self._fbthrift_inner__type
 
     @_python__property
     def value(self) -> int | float | struct1 | union1 | None:

Diff for: thrift/compiler/test/fixtures/py3/out/py3_inplace/gen-py3/module/types_inplace_FBTHRIFT_ONLY_DO_NOT_USE.py

@@ -62,6 +62,9 @@ class __BinaryUnionType(enum.Enum):
 
     __module__ = _fbthrift__module_name__
     __slots__ = ()
+
+_BinaryUnion__BinaryUnionType = __BinaryUnionType
+
 __all__.append("__BinaryUnionType")
 
 
@@ -2388,7 +2391,7 @@ class BinaryUnion(thrift.py3.types.Union):
     _FBTHRIFT__FIELD_NAMES = (
         "iobuf_val",
     )
-    Type = _fbthrift_python_types.BinaryUnion.Type
+    Type = __BinaryUnionType
     _fbthrift__inner : _fbthrift_python_types.BinaryUnion
     _fbthrift_inner__type: Type
     _fbthrift_inner__value: _fbthrift_iobuf.IOBuf | None
@@ -2440,7 +2443,9 @@ def iobuf_val(self) -> _fbthrift_iobuf.IOBuf:
 
     @_python__property
     def type(self) -> _fbthrift_python_types.BinaryUnion.Type:
-        return self._fbthrift__inner.type
+        if self._fbthrift_inner__type is None:
+            self._fbthrift_inner__type = self.Type(self._fbthrift__inner.type.value)
+        return self._fbthrift_inner__type
 
     @_python__property
     def value(self) -> _fbthrift_iobuf.IOBuf | None:

Diff for: thrift/compiler/test/fixtures/py3/out/py3_inplace_auto_migrate/gen-py3/module/types_inplace_FBTHRIFT_ONLY_DO_NOT_USE.py

@@ -62,6 +62,9 @@ class __BinaryUnionType(enum.Enum):
 
     __module__ = _fbthrift__module_name__
     __slots__ = ()
+
+_BinaryUnion__BinaryUnionType = __BinaryUnionType
+
 __all__.append("__BinaryUnionType")
 
 
@@ -2388,7 +2391,7 @@ class BinaryUnion(thrift.py3.types.Union):
     _FBTHRIFT__FIELD_NAMES = (
         "iobuf_val",
     )
-    Type = _fbthrift_python_types.BinaryUnion.Type
+    Type = __BinaryUnionType
     _fbthrift__inner : _fbthrift_python_types.BinaryUnion
     _fbthrift_inner__type: Type
     _fbthrift_inner__value: _fbthrift_iobuf.IOBuf | None
@@ -2440,7 +2443,9 @@ def iobuf_val(self) -> _fbthrift_iobuf.IOBuf:
 
     @_python__property
     def type(self) -> _fbthrift_python_types.BinaryUnion.Type:
-        return self._fbthrift__inner.type
+        if self._fbthrift_inner__type is None:
+            self._fbthrift_inner__type = self.Type(self._fbthrift__inner.type.value)
+        return self._fbthrift_inner__type
 
     @_python__property
     def value(self) -> _fbthrift_iobuf.IOBuf | None:

Diff for: thrift/lib/py3/test/auto_migrate/unions.py

@@ -82,6 +82,15 @@ def test_union_enum_dir(self) -> None:
         for itype in iter(Integers.Type):
             self.assertTrue(itype.name in contents)
 
+    def test_union_type_enum_name(self) -> None:
+        type_enum = Integers.Type
+        if is_auto_migrated():
+            self.assertEqual(type_enum.__name__, "Integers")
+        else:
+            self.assertEqual(type_enum.__name__, "__IntegersType")
+
+        self.assertIsInstance(Integers().type, Integers.Type)
+
     def test_union_enum_members(self) -> None:
         members = Integers.Type.__members__
         # Alias can't happen in this enum so these should always equal