Fix __post_init_post_parse__ is incorrectly passed keyword arguments when no __post_init__ is defined (#4361)

changes/4361-hramezani.md

@@ -0,0 +1 @@
+Fix `__post_init_post_parse__` is incorrectly passed keyword arguments when no `__post_init__` is defined

pydantic/dataclasses.py

@@ -310,8 +310,7 @@ def _add_pydantic_validation_attributes(  # noqa: C901 (ignore complexity)
                             # set arg value by default
                             initvars_and_values[f.name] = args[i]
                         except IndexError:
-                            initvars_and_values[f.name] = f.default
-                initvars_and_values.update(kwargs)
+                            initvars_and_values[f.name] = kwargs.get(f.name, f.default)
 
                 self.__post_init_post_parse__(**initvars_and_values)
 

tests/test_dataclasses.py

@@ -600,6 +600,17 @@ def test_initvars_post_init_post_parse():
     assert PathDataPostInitPostParse('world', base_path='/hello').path == Path('/hello/world')
 
 
+def test_post_init_post_parse_without_initvars():
+    @pydantic.dataclasses.dataclass
+    class Foo:
+        a: int
+
+        def __post_init_post_parse__(self):
+            ...
+
+    Foo(a=1)
+
+
 def test_classvar():
     @pydantic.dataclasses.dataclass
     class TestClassVar: