Merge pull request #121 from Fatal1ty/fix-post-deserialize-hook-pass-…

…through

Fix generated code for dataclass with hook and pass_through fields

mashumaro/core/meta/code/builder.py

@@ -345,7 +345,6 @@ def _add_unpack_method_lines(self, method_name: str) -> None:
  f"{type_name(self.cls)}] signature"
  )
  filtered_fields = []
- kwargs_only = post_deserialize is not None
  pos_args = []
  kw_args = []
  missing_kw_only = False
@@ -375,7 +374,7 @@ def _add_unpack_method_lines(self, method_name: str) -> None:
  filtered_fields.append((fname, ftype))
  if filtered_fields:
  with self.indent("try:"):
- if kwargs_only or can_be_kwargs:
+ if can_be_kwargs:
  self.add_line("kwargs = {}")
  for fname, ftype in filtered_fields:
  self.add_type_modules(ftype)
@@ -384,11 +383,7 @@ def _add_unpack_method_lines(self, method_name: str) -> None:
  if alias is None:
  alias = config.aliases.get(fname)
  self._unpack_method_set_value(
- fname,
- ftype,
- metadata,
- alias=alias,
- kwargs_only=kwargs_only,
+ fname, ftype, metadata, alias=alias
  )
  with self.indent("except TypeError:"):
  with self.indent("if not isinstance(d, dict):"):
@@ -399,19 +394,18 @@ def _add_unpack_method_lines(self, method_name: str) -> None:
  )
  with self.indent("else:"):
  self.add_line("raise")
- else:
- self.add_line("kwargs = {}")
+
+ args = [f"__{f}" for f in pos_args]
+ for kw_arg in kw_args:
+ args.append(f"{kw_arg}=__{kw_arg}")
+ if can_be_kwargs:
+ args.append("**kwargs")
+ cls_inst = f"cls({', '.join(args)})"
+
  if post_deserialize:
- self.add_line(
- f"return cls.{__POST_DESERIALIZE__}(cls(**kwargs))"
- )
+ self.add_line(f"return cls.{__POST_DESERIALIZE__}({cls_inst})")
  else:
- args = [f"__{f}" for f in pos_args]
- for kw_arg in kw_args:
- args.append(f"{kw_arg}=__{kw_arg}")
- if can_be_kwargs:
- args.append("**kwargs")
- self.add_line(f"return cls({', '.join(args)})")
+ self.add_line(f"return {cls_inst}")
 
  def _add_unpack_method_with_dialect_lines(self, method_name: str) -> None:
  if self.decoder is not None:
@@ -485,7 +479,6 @@ def _unpack_method_set_value(
  metadata: typing.Mapping,
  *,
  alias: typing.Optional[str] = None,
- kwargs_only: bool = False,
  ) -> None:
  default = self.get_field_default(fname)
  has_default = default is not MISSING
@@ -531,71 +524,48 @@ def _unpack_method_set_value(
  if could_be_none:
  with self.indent(f"if {packed_value} is not None:"):
  self.__unpack_try_set_value(
- fname,
- field_type,
- unpacked_value,
- kwargs_only,
- has_default,
+ fname, field_type, unpacked_value, has_default
  )
  with self.indent("else:"):
- self.__unpack_set_value(
- fname, "None", kwargs_only or has_default
- )
+ self.__unpack_set_value(fname, "None", has_default)
  else:
  self.__unpack_try_set_value(
- fname,
- field_type,
- unpacked_value,
- kwargs_only,
- has_default,
+ fname, field_type, unpacked_value, has_default
  )
  else:
  with self.indent(f"if {packed_value} is not MISSING:"):
  if could_be_none:
  with self.indent(f"if {packed_value} is not None:"):
  self.__unpack_try_set_value(
- fname,
- field_type,
- unpacked_value,
- kwargs_only,
- has_default,
+ fname, field_type, unpacked_value, has_default
  )
  if default is not None:
  with self.indent("else:"):
- self.__unpack_set_value(
- fname, "None", kwargs_only or has_default
- )
+ self.__unpack_set_value(fname, "None", has_default)
  else:
  self.__unpack_try_set_value(
- fname,
- field_type,
- unpacked_value,
- kwargs_only,
- has_default,
+ fname, field_type, unpacked_value, has_default
  )
 
  def __unpack_try_set_value(
  self,
  field_name: str,
  field_type_name: str,
  unpacked_value: str,
- kwargs_only: bool,
  has_default: bool,
  ) -> None:
  with self.indent("try:"):
- self.__unpack_set_value(
- field_name, unpacked_value, kwargs_only or has_default
- )
+ self.__unpack_set_value(field_name, unpacked_value, has_default)
  with self.indent("except:"):
  self.add_line(
  f"raise InvalidFieldValue("
  f"'{field_name}',{field_type_name},value,cls)"
  )
 
  def __unpack_set_value(
- self, fname: str, unpacked_value: str, kwargs_only: bool
+ self, fname: str, unpacked_value: str, in_kwargs: bool
  ) -> None:
- if kwargs_only:
+ if in_kwargs:
  self.add_line(f"kwargs['{fname}'] = {unpacked_value}")
  else:
  self.add_line(f"__{fname} = {unpacked_value}")

tests/test_hooks.py

@@ -1,9 +1,9 @@
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from typing import Any, ClassVar, Dict, Optional, no_type_check
 
 import pytest
 
-from mashumaro import DataClassDictMixin
+from mashumaro import DataClassDictMixin, field_options, pass_through
 from mashumaro.config import ADD_SERIALIZATION_CONTEXT, BaseConfig
 from mashumaro.exceptions import BadHookSignature
 
@@ -193,6 +193,28 @@ class B(A, DataClassDictMixin):
  post_serialize_hook.assert_called_once()
 
 
+def test_post_deserialize_hook_with_pass_through_field():
+ @dataclass
+ class MyClass(DataClassDictMixin):
+ x: int = field(metadata=field_options(deserialize=pass_through))
+
+ @classmethod
+ def __post_deserialize__(cls, obj):
+ return obj
+
+ assert MyClass.from_dict({"x": 42}) == MyClass(42)
+
+
+def test_post_deserialize_hook_with_empty_dataclass():
+ @dataclass
+ class MyClass(DataClassDictMixin):
+ @classmethod
+ def __post_deserialize__(cls, obj):
+ return obj # pragma no cover
+
+ assert MyClass.from_dict({}) == MyClass()
+
+
 def test_passing_context_into_hook():
  foo = FooBarBaz(foo=Foo(1), bar=Bar(baz=2), baz=3)
  assert foo.to_dict() == {"foo": {"baz": 1}, "bar": {"baz": 2}, "baz": 3}