Support for collections.UserString, accept any in Encoder, Decoder

.gitignore

@@ -3,3 +3,4 @@
 .pytest_cache
 __pycache__
 .DS_Store
+/dist

chili/decoder.py

@@ -50,6 +50,7 @@
     is_newtype,
     is_optional,
     is_typed_dict,
+    is_user_string,
     map_generic_type,
     resolve_forward_reference,
     unpack_optional,
@@ -470,6 +471,9 @@ def build_type_decoder(a_type: Type, extra_decoders: TypeDecoders = None, module
     if is_class(origin_type) and is_typed_dict(origin_type):
         return TypedDictDecoder(origin_type, extra_decoders)
 
+    if is_class(origin_type) and is_user_string(origin_type):
+        return ProxyDecoder[origin_type](origin_type)
+
     if origin_type is Union:
         type_args = get_type_args(a_type)
         if len(type_args) == 2 and type_args[-1] is type(None):  # type: ignore
@@ -568,7 +572,7 @@ def __class_getitem__(cls, item: Type) -> Type[Decoder]:  # noqa: E501
             item = decodable(item)
 
         if not hasattr(item, _DECODABLE):
-            raise DecoderError.invalid_type
+            item = decodable(item)
 
         return type(  # type: ignore
             f"{cls.__qualname__}[{item.__module__}.{item.__qualname__}]",

chili/encoder.py

@@ -33,6 +33,7 @@
     is_newtype,
     is_optional,
     is_typed_dict,
+    is_user_string,
     map_generic_type,
     resolve_forward_reference,
     unpack_optional,
@@ -379,6 +380,9 @@ def build_type_encoder(a_type: Type, extra_encoders: TypeEncoders = None, module
     if is_class(origin_type) and is_typed_dict(origin_type):
         return TypedDictEncoder(origin_type, extra_encoders)
 
+    if is_class(origin_type) and is_user_string(origin_type):
+        return ProxyEncoder[str](str)
+
     if origin_type is Union:
         type_args = get_type_args(a_type)
         if len(type_args) == 2 and type_args[-1] is type(None):
@@ -476,7 +480,7 @@ def __class_getitem__(cls, item: Any) -> Type[Encoder]:  # noqa: E501
             item = encodable(item)
 
         if not hasattr(item, _ENCODABLE):
-            raise EncoderError.invalid_type
+            item = encodable(item)
 
         return type(  # type: ignore
             f"{cls.__qualname__}[{item.__module__}.{item.__qualname__}]",

chili/typing.py

@@ -2,6 +2,7 @@
 
 import sys
 import typing
+from collections import UserString
 from dataclasses import MISSING, Field, InitVar, is_dataclass
 from enum import Enum
 from inspect import isclass as is_class
@@ -113,6 +114,9 @@ def is_typed_dict(type_name: Type) -> bool:
     return issubclass(type_name, dict) and hasattr(type_name, "__annotations__")
 
 
+def is_user_string(type_name: Type) -> bool:
+    return issubclass(type_name, UserString)
+
 def map_generic_type(type_name: Any, type_map: Dict[Any, Any]) -> Any:
     if not type_map:
         return type_name

pyproject.toml

@@ -22,7 +22,7 @@ license = "MIT"
 name = "chili"
 readme = "README.md"
 repository = "https://github.com/kodemore/chili"
-version = "2.4.2"
+version = "2.5.0"
 
 [tool.poetry.dependencies]
 gaffe = "^0.2.1"

tests/test_encoder.py

@@ -1,3 +1,5 @@
+from collections import UserString
+
 import pytest
 
 from chili import Encoder, encodable
@@ -18,12 +20,46 @@ class Example:
     assert instance.__generic__ == Example
 
 
-def test_fail_encode_non_encodable_type() -> None:
+def test_can_encode_non_encodable_type() -> None:
     # given
     class Example:
         name: str
         age: int
 
+        def __init__(self, name: str, age: int):
+            self.name = name
+            self.age = age
+
     # when
-    with pytest.raises(EncoderError.invalid_type):
-        Encoder[Example]()
+    encoder = Encoder[Example]()
+    value = encoder.encode(Example("bob", 33))
+
+    # then
+    assert value == {
+        "name": "bob",
+        "age": 33,
+    }
+
+
+def test_can_encode_complex_non_encodable_type() -> None:
+    # given
+    class ExampleName(UserString):
+        pass
+
+    class Example:
+        name: ExampleName
+        age: int
+
+        def __init__(self, name: ExampleName, age: int):
+            self.name = name
+            self.age = age
+
+    # when
+    encoder = Encoder[Example]()
+    value = encoder.encode(Example(ExampleName("bob"), 33))
+
+    # then
+    assert value == {
+        "name": "bob",
+        "age": 33,
+    }

tests/usecases/userstring_test.py

@@ -0,0 +1,32 @@
+from collections import UserString
+
+from chili import decode, encode
+
+
+def test_can_encode_userstring() -> None:
+    # given
+    class ComplexString(UserString):
+        pass
+
+    string = ComplexString("Example String")
+
+    # when
+    result = encode(string)
+
+    # then
+    assert result == "Example String"
+
+
+def test_can_decode_userstring() -> None:
+    # given
+    class ComplexString(UserString):
+        pass
+    string = "Example String"
+
+    # when
+    result = decode(string, ComplexString)
+
+    # then
+    assert result == ComplexString("Example String")
+    assert isinstance(result, ComplexString)
+    assert isinstance(result, UserString)