Support Python 2.7 (#35)

- Always extend object where required.
- Use explicit super() calls everywhere.
- Handle string and unicode problems in tests.
- Only lint and codecov on Python 3.7.

.travis.yml

@@ -1,6 +1,7 @@
 language: python
 matrix:
   include:
+    - python: 2.7
     - python: 3.4
     - python: 3.5
     - python: 3.6
@@ -15,9 +16,9 @@ install:
 
 # command to run tests
 script:
-  - make lint
-  - make test
+  - if [[ $TRAVIS_PYTHON_VERSION == 3.7 ]]; then make lint; fi
+  - if [[ $TRAVIS_PYTHON_VERSION != 2.7 ]]; then make test; else make test-plain; fi
 
 # command to upload coverage
 after_success:
-  - codecov
+  - if [[ $TRAVIS_PYTHON_VERSION == 3.7 ]]; then codecov; fi

Makefile

@@ -1,5 +1,5 @@
 .PHONY: help clean venv install install-travis install-all lint sort-imports \
-		test docs docs-clean docs-open docs-test dist release
+		test test-plain docs docs-clean docs-open docs-test dist release
 
 PYTHON := python3
 VIRTUAL_ENV := $(or $(VIRTUAL_ENV), $(VIRTUAL_ENV), venv)
@@ -35,6 +35,9 @@ test: ## Run all tests.
 	$(VIRTUAL_ENV)/bin/pytest -vv --cov=serde --cov-report term-missing --cov-fail-under 100 \
 								  --doctest-modules --doctest-import "*<serde"
 
+test-plain: ## Run tests excluding doctests.
+	$(VIRTUAL_ENV)/bin/pytest -vv --cov=serde --cov-report term-missing
+
 docs: ## Compile docs.
 	$(MAKE) -C docs html
 

setup.py

@@ -22,6 +22,7 @@
 
 install_requires = [
     'isodate>=0.6.0<0.7.0',
+    'six>=1.0.0<2.0.0',
     'validators>=0.12.0<0.13.0'
 ]
 
@@ -43,6 +44,7 @@
 ]
 
 test_requires = [
+    'mock',
     'pytest>=3.3.0',
     'pytest-cov',
     'pytest-doctest-import'
@@ -67,7 +69,7 @@
         'documenting': document_requires,
         'packaging': package_requires
     },
-    python_requires='>=3.4',
+    python_requires='>=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*',
     packages=find_packages('src'),
     package_dir={'': 'src'},
     py_modules=['serde'],

src/serde/__init__.py

@@ -53,7 +53,7 @@
 found in `~serde.field`.
 """
 
-from .model import Model
+from serde.model import Model
 
 
 __all__ = ['Model', 'error', 'field', 'validate']

src/serde/error.py

@@ -27,7 +27,7 @@ def __init__(self, message, cause=None, value=None, field=None, model=None):
             field (~serde.field.Field): the Field context.
             model (~serde.model.Model): the Model context.
         """
-        super().__init__(message)
+        super(SerdeError, self).__init__(message)
         self.cause = None
         self.value = None
         self.field = None
@@ -51,7 +51,7 @@ def add_context(self, cause=None, value=None, field=None, model=None):
             field (~serde.field.Field): the Field context.
             model (~serde.model.Model): the Model context.
         """
-        from .model import Model
+        from serde.model import Model
 
         if cause is not None:
             self.cause = cause
@@ -74,7 +74,7 @@ def __repr__(self):
         """
         return '<{}.{}: {}>'.format(
             self.__class__.__module__,
-            self.__class__.__qualname__,
+            self.__class__.__name__,
             self.message
         )
 

src/serde/field.py

@@ -80,9 +80,9 @@
 
 import isodate
 
-from . import validate
-from .error import SerdeError
-from .util import zip_equal
+from serde import validate
+from serde.error import SerdeError
+from serde.util import zip_equal
 
 
 __all__ = [
@@ -132,7 +132,7 @@ def _resolve_to_field_instance(thing, none_allowed=True):
         Field: a field instance.
     """
     # We import Model here to avoid circular dependency problems.
-    from .model import Model
+    from serde.model import Model
 
     # If the thing is None then return a generic Field instance.
     if none_allowed and thing is None:
@@ -180,7 +180,7 @@ def _resolve_to_field_instance(thing, none_allowed=True):
     )
 
 
-class Field:
+class Field(object):
     """
     A field on a `~serde.model.Model`.
 
@@ -218,7 +218,7 @@ def __init__(
                 to validate as an argument. The functions need to raise an
                 `Exception` if they fail.
         """
-        super().__init__()
+        super(Field, self).__init__()
 
         self.id = Field.__counter
         Field.__counter += 1
@@ -256,7 +256,7 @@ def __setattr__(self, name, value):
         if name == '_name' and hasattr(self, '_name'):
             raise SerdeError('field instance used multiple times')
 
-        super().__setattr__(name, value)
+        super(Field, self).__setattr__(name, value)
 
     def _serialize(self, value):
         """
@@ -471,7 +471,7 @@ def __init__(self, type, **kwargs):
             type: the type that this Field wraps.
             **kwargs: keyword arguments for the `Field` constructor.
         """
-        super().__init__(**kwargs)
+        super(Instance, self).__init__(**kwargs)
         self.type = type
 
     def validate(self, value):
@@ -481,7 +481,7 @@ def validate(self, value):
         Args:
             value: the value to validate.
         """
-        super().validate(value)
+        super(Instance, self).validate(value)
         validate.instance(self.type)(value)
 
 
@@ -548,7 +548,7 @@ def __init__(self, model, dict=None, strict=True, **kwargs):
                 unknown dictionary keys are present when deserializing.
             **kwargs: keyword arguments for the `Field` constructor.
         """
-        super().__init__(model, **kwargs)
+        super(Nested, self).__init__(model, **kwargs)
         self.dict = dict
         self.strict = strict
 
@@ -563,7 +563,7 @@ def serialize(self, value):
             dict: the serialized dictionary.
         """
         value = value.to_dict(dict=self.dict)
-        return super().serialize(value)
+        return super(Nested, self).serialize(value)
 
     def deserialize(self, value):
         """
@@ -576,7 +576,7 @@ def deserialize(self, value):
             Model: the deserialized model.
         """
         value = self.type.from_dict(value, strict=self.strict)
-        return super().deserialize(value)
+        return super(Nested, self).deserialize(value)
 
 
 class Dict(Instance):
@@ -629,7 +629,7 @@ def __init__(self, key=None, value=None, **kwargs):
             value (Field): the Field class/instance for values in this Dict.
             **kwargs: keyword arguments for the `Field` constructor.
         """
-        super().__init__(dict, **kwargs)
+        super(Dict, self).__init__(dict, **kwargs)
         self.key = _resolve_to_field_instance(key)
         self.value = _resolve_to_field_instance(value)
 
@@ -647,7 +647,7 @@ def serialize(self, value):
             dict: the serialized dictionary.
         """
         value = {self.key.serialize(k): self.value.serialize(v) for k, v in value.items()}
-        return super().serialize(value)
+        return super(Dict, self).serialize(value)
 
     def deserialize(self, value):
         """
@@ -662,7 +662,7 @@ def deserialize(self, value):
         Returns:
             dict: the deserialized dictionary.
         """
-        value = super().deserialize(value)
+        value = super(Dict, self).deserialize(value)
         return {self.key.deserialize(k): self.value.deserialize(v) for k, v in value.items()}
 
     def validate(self, value):
@@ -675,7 +675,7 @@ def validate(self, value):
         Args:
             value (dict): the dictionary to validate.
         """
-        super().validate(value)
+        super(Dict, self).validate(value)
 
         for k, v in value.items():
             self.key.validate(k)
@@ -724,7 +724,7 @@ def __init__(self, element=None, **kwargs):
             element (Field): the Field class/instance for elements in the List.
             **kwargs: keyword arguments for the `Field` constructor.
         """
-        super().__init__(list, **kwargs)
+        super(List, self).__init__(list, **kwargs)
         self.element = _resolve_to_field_instance(element)
 
     def serialize(self, value):
@@ -741,7 +741,7 @@ def serialize(self, value):
             list: the serialized list.
         """
         value = [self.element.serialize(v) for v in value]
-        return super().serialize(value)
+        return super(List, self).serialize(value)
 
     def deserialize(self, value):
         """
@@ -756,7 +756,7 @@ def deserialize(self, value):
         Returns:
             list: the deserialized list.
         """
-        value = super().deserialize(value)
+        value = super(List, self).deserialize(value)
         return [self.element.deserialize(v) for v in value]
 
     def validate(self, value):
@@ -769,7 +769,7 @@ def validate(self, value):
         Args:
             value (list): the list to validate.
         """
-        super().validate(value)
+        super(List, self).validate(value)
 
         for v in value:
             self.element.validate(v)
@@ -822,7 +822,7 @@ def __init__(self, *elements, **kwargs):
                 Tuple.
             **kwargs: keyword arguments for the `Field` constructor.
         """
-        super().__init__(tuple, **kwargs)
+        super(Tuple, self).__init__(tuple, **kwargs)
         self.elements = tuple(_resolve_to_field_instance(e, none_allowed=False) for e in elements)
 
     def serialize(self, value):
@@ -853,7 +853,7 @@ def deserialize(self, value):
         Returns:
             tuple: the deserialized tuple.
         """
-        value = super().deserialize(value)
+        value = super(Tuple, self).deserialize(value)
         return tuple(e.deserialize(v) for e, v in zip_equal(self.elements, value))
 
     def validate(self, value):
@@ -866,7 +866,7 @@ def validate(self, value):
         Args:
             value (tuple): the tuple to validate.
         """
-        super().validate(value)
+        super(Tuple, self).validate(value)
 
         for e, v in zip_equal(self.elements, value):
             e.validate(v)
@@ -890,6 +890,18 @@ def validate(self, value):
 #: This field represents the built-in `str` type.
 Str = create('Str', base=Instance, args=(str,))
 
+try:
+    #: This field represents the built-in `basestring` type.
+    BaseString = create('BaseString', base=Instance, args=(basestring,))
+except NameError:
+    pass
+
+try:
+    #: This field represents the built-in `unicode` type.
+    Unicode = create('Unicode', base=Instance, args=(unicode,))
+except NameError:
+    pass
+
 # Str types with extra validation.
 Domain = create('Domain', base=Str, validators=[validate.domain])
 Email = create('Email', base=Str, validators=[validate.email])
@@ -938,7 +950,7 @@ def __init__(self, choices, **kwargs):
             choices: a list/range/tuple of allowed values.
             **kwargs: keyword arguments for the `Field` constructor.
         """
-        super().__init__(**kwargs)
+        super(Choice, self).__init__(**kwargs)
         self.choices = choices
 
     def validate(self, value):
@@ -982,7 +994,7 @@ def __init__(self, format='iso8601', **kwargs):
                 ISO 8601 datetimes.
             **kwargs: keyword arguments for the `Field` constructor.
         """
-        super().__init__(self.__class__.type, **kwargs)
+        super(DateTime, self).__init__(self.__class__.type, **kwargs)
         self.format = format
 
     def serialize(self, value):
@@ -1096,7 +1108,7 @@ def __init__(self, **kwargs):
         Args:
             **kwargs: keyword arguments for the `Field` constructor.
         """
-        super().__init__(uuid.UUID, **kwargs)
+        super(Uuid, self).__init__(uuid.UUID, **kwargs)
 
     def serialize(self, value):
         """

src/serde/model.py

@@ -74,9 +74,11 @@
 from collections import OrderedDict
 from functools import wraps
 
-from .error import DeserializationError, SerdeError, SerializationError, ValidationError
-from .field import Field
-from .util import try_import, zip_until_right
+from six import with_metaclass
+
+from serde.error import DeserializationError, SerdeError, SerializationError, ValidationError
+from serde.field import Field
+from serde.util import try_import, zip_until_right
 
 
 toml = try_import('toml')
@@ -190,7 +192,7 @@ def __getattr__(self, name):
         try:
             return self[name]
         except KeyError:
-            return super().__getattribute__(name)
+            return super(Fields, self).__getattribute__(name)
 
 
 class ModelType(type):
@@ -235,10 +237,10 @@ def __new__(cls, cname, bases, attrs):
         # they were defined on the Models. We add these to the Model.
         final_attrs['_fields'] = Fields(sorted(fields.items(), key=lambda x: x[1].id))
 
-        return super().__new__(cls, cname, bases, final_attrs)
+        return super(ModelType, cls).__new__(cls, cname, bases, final_attrs)
 
 
-class Model(metaclass=ModelType):
+class Model(with_metaclass(ModelType, object)):
     """
     The base Model to be subclassed.
     """
@@ -251,7 +253,7 @@ def __init__(self, *args, **kwargs):
             *args: positional arguments values for each Fields on the Model. If
                 these are given they will be interpreted as corresponding to the
                 Fields in the order the Fields are defined on the Model.
-            **kwargs: keyboard argument values for each Field on the Model.
+            **kwargs: keyword argument values for each Field on the Model.
         """
         try:
             named_args = list(zip_until_right(self._fields.keys(), args))