All pending dacite PRs

.github/workflows/code_check.yaml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [ '3.7', '3.8', '3.9', '3.10' ]
+        python-version: [ '3.7', '3.8', '3.9', '3.10', '3.11' ]
 
     name: Python ${{ matrix.python-version }}
     steps:

.gitignore

@@ -1,5 +1,8 @@
 .pytest_cache/
+.mypy_cache/
 *.pyc
 dist/
 *.egg-info/
-build/
+build/
+/venv/
+/.idea/

.travis.yml

@@ -1,16 +1,17 @@
 dist: xenial
 language: python
 python:
-- 3.6
 - 3.7
 - 3.8
-- 3.9-dev
+- 3.9
+- 3.10
+- 3.11
 install:
 - pip install -e .[dev]
 script:
 - pytest --cov=dacite
 - black --check .
-- mypy dacite
+- mypy
 - pylint dacite
 after_success:
   coveralls

CHANGELOG.md

@@ -7,13 +7,30 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [2.0b1] - 2022-11-28
+
 ### Added
 
 - Add explicit `__all__` configuration
+- Support [PEP 604] unions through `types.UnionType` #184
+- numpy.typing.NDArray dataclass members #156
+- Add `allow_missing_fields_as_none` option for missing fields #199
+- Ability to customize `from_dict` per dataclass #122
+- more general type hint for `type_hooks` #120
+- Add Generic Hook Types #83
+- Add stricter mypy type check flags #76
+
+[PEP 604]: https://peps.python.org/pep-0604/
 
 ### Fixed
 
 - Do not suppress `KeyError` in a type hook
+- `from_dict` in case of frozen dataclass with non-init default #196
+- empty tuple used for Sequence type #175
+- Type_hooks not applied to InitVar fields #172
+- extract_optional for Optional of Union. #164
+- change Data from Dict to Mapping #159
+- Fix encoding of PKG-INFO file #86
 
 ## [1.6.0] - 2020-11-30
 

README.md

@@ -20,7 +20,7 @@ $ pip install dacite
 
 ## Requirements
 
-Minimum Python version supported by `dacite` is 3.6.
+Minimum Python version supported by `dacite` is 3.7.
 
 ## Quick start
 
@@ -235,8 +235,7 @@ assert result == B(a_list=[A(x='test1', y=1), A(x='test2', y=2)])
 
 You can use `Config.type_hooks` argument if you want to transform the input 
 data of a data class field with given type into the new value. You have to 
-pass a following mapping: `{Type: callable}`, where `callable` is a 
-`Callable[[Any], Any]`.
+pass a mapping of type `Mapping[Type, Callable[[Any], Any]`.
 
 ```python
 @dataclass
@@ -258,6 +257,56 @@ If a data class field type is a `Optional[T]` you can pass both -
 collections, e.g. when a field has type `List[T]` you can use `List[T]` to 
 transform whole collection or `T` to transform each item. 
 
+To target all types use `Any`.  Targeting collections without their sub-types
+will target all collections of those types, such as `List` and `Dict`. 
+
+```python
+@dataclass
+class ShoppingCart:
+    store: str
+    item_ids: List[int]
+
+data = {
+    'store': '7-Eleven',
+    'item_ids': [1, 2, 3],
+}
+
+def print_value(value):
+    print(value)
+    return value
+
+def print_collection(collection):
+    for item in collection:
+        print(item)
+    return collection
+
+result = from_dict(
+    data_class=ShoppingCart, 
+    data=data, 
+    config=Config(
+        type_hooks={
+            Any: print_value, 
+            List: print_collection
+        }
+    )
+)
+```
+
+prints
+
+```
+7-Eleven
+[1, 2, 3]
+1
+2
+3
+```
+
+If a data class field type is a `Optional[T]` you can pass both - 
+`Optional[T]` or just `T` - as a key in `type_hooks`. The same with generic 
+collections, e.g. when a field has type `List[T]` you can use `List[T]` to 
+transform whole collection or `T` to transform each item. 
+
 ### Casting
 
 It's a very common case that you want to create an instance of a field type 

dacite/config.py

@@ -1,12 +1,13 @@
 from dataclasses import dataclass, field
-from typing import Dict, Any, Callable, Optional, Type, List
+from typing import Dict, Any, Callable, Optional, Type, List, Union, Mapping
 
 
 @dataclass
 class Config:
-    type_hooks: Dict[Type, Callable[[Any], Any]] = field(default_factory=dict)
+    type_hooks: Mapping[Union[Type, object], Callable[[Any], Any]] = field(default_factory=dict)
     cast: List[Type] = field(default_factory=list)
     forward_references: Optional[Dict[str, Any]] = None
     check_types: bool = True
     strict: bool = False
     strict_unions_match: bool = False
+    allow_missing_fields_as_none: bool = False

dacite/core.py

@@ -1,10 +1,10 @@
 import copy
 from dataclasses import is_dataclass
 from itertools import zip_longest
-from typing import TypeVar, Type, Optional, get_type_hints, Mapping, Any
+from typing import TypeVar, Type, Optional, Mapping, Any
 
 from dacite.config import Config
-from dacite.data import Data
+from dacite.data import Data, DictData
 from dacite.dataclasses import get_default_value_for_field, create_instance, DefaultValueNotFoundError, get_fields
 from dacite.exceptions import (
     ForwardReferenceError,
@@ -27,6 +27,7 @@
     is_init_var,
     extract_init_var,
     is_set,
+    get_data_class_hints,
 )
 
 T = TypeVar("T")
@@ -40,11 +41,11 @@ def from_dict(data_class: Type[T], data: Data, config: Optional[Config] = None)
     :param config: a configuration of the creation process
     :return: an instance of a data class
     """
-    init_values: Data = {}
-    post_init_values: Data = {}
+    init_values: DictData = {}
+    post_init_values: DictData = {}
     config = config or Config()
     try:
-        data_class_hints = get_type_hints(data_class, globalns=config.forward_references)
+        data_class_hints = get_data_class_hints(data_class, globalns=config.forward_references)
     except NameError as error:
         raise ForwardReferenceError(str(error))
     data_class_fields = get_fields(data_class)
@@ -67,12 +68,16 @@ def from_dict(data_class: Type[T], data: Data, config: Optional[Config] = None)
                 raise
             if config.check_types and not is_instance(value, field.type):
                 raise WrongTypeError(field_path=field.name, field_type=field.type, value=value)
+        elif not field.init:
+            # If the non-init field isn't in the dict, let the dataclass handle default, to ensure
+            # we won't get errors in the case of frozen dataclasses, as issue #195 highlights.
+            continue
         else:
             try:
-                value = get_default_value_for_field(field)
+                value = get_default_value_for_field(
+                    field, allow_missing_fields_as_none=config.allow_missing_fields_as_none
+                )
             except DefaultValueNotFoundError:
-                if not field.init:
-                    continue
                 raise MissingValueError(field.name)
         if field.init:
             init_values[field.name] = value
@@ -96,6 +101,8 @@ def _build_value(type_: Type, data: Any, config: Config) -> Any:
                 _build_value(type_=extract_generic(type_)[0], data=single_val, config=config) for single_val in data
             )
     elif is_dataclass(type_) and is_instance(data, Data):
+        if hasattr(type_, "from_dict"):
+            return type_.from_dict(data=data, config=config)
         return from_dict(data_class=type_, data=data, config=config)
     return data
 
@@ -137,6 +144,8 @@ def _build_value_for_collection(collection: Type, data: Any, config: Config) ->
         item_type = extract_generic(collection, defaults=(Any, Any))[1]
         return data_type((key, _build_value(type_=item_type, data=value, config=config)) for key, value in data.items())
     elif is_instance(data, tuple):
+        if not data:
+            return data_type()
         types = extract_generic(collection)
         if len(types) == 2 and types[1] == Ellipsis:
             return data_type(_build_value(type_=types[0], data=item, config=config) for item in data)

dacite/data.py

@@ -1,3 +1,4 @@
-from typing import Dict, Any
+from typing import Dict, Mapping, Any
 
-Data = Dict[str, Any]
+Data = Mapping[str, Any]
+DictData = Dict[str, Any]

dacite/dataclasses.py

@@ -11,18 +11,18 @@ class DefaultValueNotFoundError(Exception):
     pass
 
 
-def get_default_value_for_field(field: Field) -> Any:
+def get_default_value_for_field(field: Field, allow_missing_fields_as_none: bool = False) -> Any:
     if field.default != MISSING:
         return field.default
-    elif field.default_factory != MISSING:  # type: ignore
-        return field.default_factory()  # type: ignore
-    elif is_optional(field.type):
+    elif field.default_factory != MISSING:
+        return field.default_factory()
+    elif is_optional(field.type) or allow_missing_fields_as_none:
         return None
     raise DefaultValueNotFoundError()
 
 
 def create_instance(data_class: Type[T], init_values: Data, post_init_values: Data) -> T:
-    instance = data_class(**init_values)
+    instance: T = data_class(**init_values)
     for key, value in post_init_values.items():
         setattr(instance, key, value)
     return instance