Don't implement beartype for dataclass without serde

Closes #480

serde/de.py

@@ -438,7 +438,10 @@ def deserializable_to_obj(cls: Type[T]) -> T:
     try:
         thisfunc = functools.partial(from_obj, named=named, reuse_instances=reuse_instances)
         if is_dataclass_without_de(c):
-            deserialize(c)
+            # Do not automatically implement beartype if dataclass without serde decorator
+            # is passed, because it is surprising for users
+            # See https://github.com/yukinarit/pyserde/issues/480
+            deserialize(c, type_check=disabled)
             res = deserializable_to_obj(c)
         elif is_deserializable(c):
             res = deserializable_to_obj(c)

serde/se.py

@@ -366,7 +366,10 @@ def serializable_to_obj(object: Any) -> Any:
         if o is None:
             return None
         if is_dataclass_without_se(o):
-            serialize(type(o))
+            # Do not automatically implement beartype if dataclass without serde decorator
+            # is passed, because it is surprising for users
+            # See https://github.com/yukinarit/pyserde/issues/480
+            serialize(type(o), type_check=disabled)
             return serializable_to_obj(o)
         elif is_serializable(o):
             return serializable_to_obj(o)

tests/test_type_check.py

@@ -1,3 +1,4 @@
+from dataclasses import dataclass
 import datetime
 import pathlib
 from beartype.roar import BeartypeCallHintViolation
@@ -15,6 +16,7 @@
 import pytest
 
 import serde
+import serde.json
 
 from . import data
 
@@ -100,6 +102,18 @@ class C:
         serde.from_dict(C, d)
 
 
+def test_type_check_disabled_for_dataclass_without_serde() -> None:
+    @dataclass
+    class Foo:
+        value: int
+
+    f = Foo("100")  # type: ignore
+    data = serde.json.to_json(f)
+    assert f == serde.json.from_json(Foo, data)
+
+    f = Foo("100")  # type: ignore
+
+
 def test_uncoercible() -> None:
     @serde.serde(type_check=serde.coerce)
     class Foo: