Take make_dict_structure_fn.prefer_attrib_converters from converter

Author: Tinche

HISTORY.md

@@ -17,6 +17,8 @@ Our backwards-compatibility policy can be found [here](https://github.com/python
   ([#473](https://github.com/python-attrs/cattrs/pull/473))
 - **Minor change**: Heterogeneous tuples are now unstructured into tuples instead of lists by default; this is significantly faster and widely supported by serialization libraries.
   ([#486](https://github.com/python-attrs/cattrs/pull/486))
+- **Minor change**: {py:func}`cattrs.gen.make_dict_structure_fn` will use the value for the `prefer_attrib_converters` parameter from the given converter by default now.
+  If you're using this function directly, the old behavior can be restored by passing in the desired values explicitly.
 - Introduce {meth}`BaseConverter.get_structure_hook` and {meth}`BaseConverter.get_unstructure_hook` methods.
   ([#432](https://github.com/python-attrs/cattrs/issues/432) [#472](https://github.com/python-attrs/cattrs/pull/472))
 - {meth}`BaseConverter.register_structure_hook`, {meth}`BaseConverter.register_unstructure_hook`,

src/cattrs/gen/__init__.py

@@ -258,7 +258,9 @@ def make_dict_structure_fn(
     converter: BaseConverter,
     _cattrs_forbid_extra_keys: bool | Literal["from_converter"] = "from_converter",
     _cattrs_use_linecache: bool = True,
-    _cattrs_prefer_attrib_converters: bool = False,
+    _cattrs_prefer_attrib_converters: (
+        bool | Literal["from_converter"]
+    ) = "from_converter",
     _cattrs_detailed_validation: bool | Literal["from_converter"] = "from_converter",
     _cattrs_use_alias: bool = False,
     _cattrs_include_init_false: bool = False,
@@ -289,6 +291,9 @@ def make_dict_structure_fn(
     ..  versionchanged:: 23.2.0
         The `_cattrs_forbid_extra_keys` and `_cattrs_detailed_validation` parameters
         take their values from the given converter by default.
+    ..  versionchanged:: 24.1.0
+        The `_cattrs_prefer_attrib_converters` parameter takes its value from the given
+        converter by default.
     """
 
     mapping = {}
@@ -344,6 +349,8 @@ def make_dict_structure_fn(
         _cattrs_forbid_extra_keys = getattr(converter, "forbid_extra_keys", False)
     if _cattrs_detailed_validation == "from_converter":
         _cattrs_detailed_validation = converter.detailed_validation
+    if _cattrs_prefer_attrib_converters == "from_converter":
+        _cattrs_prefer_attrib_converters = converter._prefer_attrib_converters
 
     if _cattrs_forbid_extra_keys:
         globs["__c_a"] = allowed_fields

tests/test_gen_dict.py

@@ -633,6 +633,26 @@ class A:
             converter.structure({"a": "a"}, A)
 
 
+@given(prefer=...)
+def test_prefer_converters_from_converter(prefer: bool):
+    """
+    `prefer_attrs_converters` is taken from the converter by default.
+    """
+
+    @define
+    class A:
+        a: int = field(converter=lambda x: x + 1)
+
+    converter = BaseConverter(prefer_attrib_converters=prefer)
+    converter.register_structure_hook(int, lambda x, _: x + 1)
+    converter.register_structure_hook(A, make_dict_structure_fn(A, converter))
+
+    if prefer:
+        assert converter.structure({"a": 1}, A).a == 2
+    else:
+        assert converter.structure({"a": 1}, A).a == 3
+
+
 def test_fields_exception():
     """fields() raises on a non-attrs, non-dataclass class."""
     with pytest.raises(Exception):  # noqa: B017