Merge pull request #218 from Fatal1ty/mappingproxy

Add support for MappingProxyType

README.md

@@ -221,6 +221,7 @@ for special primitives from the [`typing`](https://docs.python.org/3/library/typ
 for standard interpreter types from [`types`](https://docs.python.org/3/library/types.html#standard-interpreter-types) module:
 * [`NoneType`](https://docs.python.org/3/library/types.html#types.NoneType)
 * [`UnionType`](https://docs.python.org/3/library/types.html#types.UnionType)
+* [`MappingProxyType`](https://docs.python.org/3/library/types.html#types.MappingProxyType)
 
 for enumerations based on classes from the standard [`enum`](https://docs.python.org/3/library/enum.html) module:
 * [`Enum`](https://docs.python.org/3/library/enum.html#enum.Enum)

mashumaro/core/meta/types/unpack.py

@@ -1230,6 +1230,12 @@ def inner_expr(
         )
     elif is_typed_dict(spec.origin_type):
         return unpack_typed_dict(spec)
+    elif issubclass(spec.origin_type, types.MappingProxyType):
+        spec.builder.ensure_module_imported(types)
+        return (
+            f'types.MappingProxyType({{{inner_expr(0, "key")}: {inner_expr(1)}'
+            f" for key, value in {spec.expression}.items()}})"
+        )
     elif ensure_generic_mapping(spec, args, typing.Mapping):
         return (
             f'{{{inner_expr(0, "key")}: {inner_expr(1)} '

tests/test_data_types.py

@@ -16,6 +16,7 @@
     WindowsPath,
 )
 from queue import Queue
+from types import MappingProxyType
 from typing import (
     Any,
     AnyStr,
@@ -123,6 +124,7 @@ class Fixture:
     DICT = {"a": 1, "b": 2}
     ORDERED_DICT = collections.OrderedDict(a=1, b=2)
     DEFAULT_DICT = collections.defaultdict(int, a=1, b=2)
+    MAPPING_PROXY = MappingProxyType(DICT)
     DEFAULT_NONE_DICT = collections.defaultdict(None, a=1, b=2)
     COUNTER: Counter[str] = collections.Counter(a=1, b=2)
     BYTES = b"123"
@@ -334,7 +336,13 @@ class Fixture:
     )
 
 if PY_39_MIN:
-    inner_values.append((ZoneInfo, ZoneInfo("Europe/Moscow"), "Europe/Moscow"))
+    inner_values.extend(
+        (
+            (ZoneInfo, ZoneInfo("Europe/Moscow"), "Europe/Moscow"),
+            (MappingProxyType[str, int], Fixture.MAPPING_PROXY, Fixture.DICT),
+            (MappingProxyType, Fixture.MAPPING_PROXY, Fixture.DICT),
+        )
+    )
 
 
 hashable_inner_values = [

tests/test_meta.py

@@ -1,5 +1,6 @@
 import collections
 import collections.abc
+import types
 import typing
 from dataclasses import InitVar, dataclass
 from datetime import datetime
@@ -8,7 +9,12 @@
 import typing_extensions
 
 from mashumaro import DataClassDictMixin
-from mashumaro.core.const import PEP_585_COMPATIBLE, PY_38, PY_310_MIN
+from mashumaro.core.const import (
+    PEP_585_COMPATIBLE,
+    PY_38,
+    PY_39_MIN,
+    PY_310_MIN,
+)
 from mashumaro.core.meta.code.builder import CodeBuilder
 
 # noinspection PyProtectedMember
@@ -229,6 +235,11 @@ def test_type_name():
     )
     assert type_name(typing.Optional[NoneType]) == "NoneType"
 
+    if PY_39_MIN:
+        assert (
+            type_name(types.MappingProxyType[int, int])
+            == "mappingproxy[int, int]"
+        )
     if PY_310_MIN:
         assert type_name(int | None) == "typing.Optional[int]"
         assert type_name(None | int) == "typing.Optional[int]"
@@ -340,6 +351,11 @@ def test_type_name_short():
     )
     assert type_name(typing.Optional[NoneType], short=True) == "NoneType"
 
+    if PY_39_MIN:
+        assert (
+            type_name(types.MappingProxyType[int, int], short=True)
+            == "mappingproxy[int, int]"
+        )
     if PY_310_MIN:
         assert type_name(int | None, short=True) == "Optional[int]"
         assert type_name(None | int, short=True) == "Optional[int]"