assert_instance_of and assert_subclass_of (used in the validate inline entry point) fixed so as to support Enum types. Fixed #28. **Important**: only tuple are now supported when several types are provided in validate's instance_of and subclass_of arguments. This is to has a closer behaviour to the python stdlib.

Author: Sylvain MARIE

.travis.yml

@@ -31,6 +31,7 @@ install:
     if [ "${TRAVIS_PYTHON_VERSION}" = "2.7" ]; then
       echo "No need to install enforce pytypes checktypes BUT need to install future"
       pip install future
+      pip install enum34
     else
       pip install autoclass
       pip install enforce

setup.py

@@ -13,7 +13,7 @@
 # *************** Dependencies *********
 INSTALL_REQUIRES = ['makefun', 'future;python_version<"3.3"', 'funcsigs;python_version<"3.3"', 'decopatch'] # 'typing_inspect' is now copied internally so as to be compliant with very old versions of typing module
 DEPENDENCY_LINKS = []
-SETUP_REQUIRES = ['pytest-runner', 'setuptools_scm', 'pypandoc', 'pandoc']
+SETUP_REQUIRES = ['pytest-runner', 'setuptools_scm', 'pypandoc', 'pandoc', 'enum34;python_version<"3.4"']
 TESTS_REQUIRE = ['pytest', 'pytest-logging', 'pytest-cov', 'enforce', 'mini_lambda', 'attrs', 'numpy', 'autoclass',
                  'checktypes', 'pytest-cases']
 EXTRAS_REQUIRE = {}

valid8/entry_points_inline.py

@@ -1,4 +1,5 @@
 import sys
+from inspect import isclass
 from warnings import warn
 
 from linecache import getline
@@ -12,7 +13,7 @@
 
 try:  # python 3.5+
     # noinspection PyUnresolvedReferences
-    from typing import Any, Union, Set, Iterable, Callable, Container
+    from typing import Any, Union, Set, Iterable, Callable, Container, Tuple
     try:  # python 3.5.3-
         from typing import Type
     except ImportError:
@@ -22,7 +23,7 @@
 
 
 def assert_instance_of(value,
-                       allowed_types  # type: Union[type, Iterable[type]]
+                       allowed_types  # type: Union[Type, Tuple[Type]]
                        ):
     """
     An inlined version of instance_of(var_types)(value) without 'return True': it does not return anything in case of
@@ -31,16 +32,10 @@ def assert_instance_of(value,
     Used in validate and validation/validator
 
     :param value: the value to check
-    :param allowed_types: the type(s) to enforce. If a set of types is provided it is considered alternate types: one
+    :param allowed_types: the type(s) to enforce. If a tuple of types is provided it is considered alternate types: one
         match is enough to succeed. If None, type will not be enforced
     :return:
     """
-    try:
-        # isinstance does not allow anything else than tuples when several are provided
-        allowed_types = tuple(allowed_types)
-    except TypeError:
-        pass
-
     if not isinstance(value, allowed_types):
         try:
             # more than 1 ?
@@ -57,7 +52,7 @@ def assert_instance_of(value,
 
 
 def assert_subclass_of(typ,
-                       allowed_types  # type: Union[type, Iterable[type]]
+                       allowed_types  # type: Union[Type, Tuple[Type]]
                        ):
     """
     An inlined version of subclass_of(var_types)(value) without 'return True': it does not return anything in case of
@@ -66,16 +61,10 @@ def assert_subclass_of(typ,
     Used in validate and validation/validator
 
     :param typ: the type to check
-    :param allowed_types: the type(s) to enforce. If a set of types is provided it is considered alternate types:
+    :param allowed_types: the type(s) to enforce. If a tuple of types is provided it is considered alternate types:
         one match is enough to succeed. If None, type will not be enforced
     :return:
     """
-    try:
-        # issubclass does not allow anything else than tuples when several are provided
-        allowed_types = tuple(allowed_types)
-    except TypeError:
-        pass
-
     if not issubclass(typ, allowed_types):
         try:
             # more than 1 ?
@@ -137,8 +126,8 @@ def validate(name,                   # type: str
              value,                  # type: Any
              enforce_not_none=True,  # type: bool
              equals=None,            # type: Any
-             instance_of=None,       # type: Union[type, Iterable[type]]
-             subclass_of=None,       # type: Union[type, Iterable[type]]
+             instance_of=None,       # type: Union[Type, Tuple[Type]]
+             subclass_of=None,       # type: Union[Type, Tuple[Type]]
              is_in=None,             # type: Container
              subset_of=None,         # type: Set
              contains = None,        # type: Union[Any, Iterable]
@@ -172,9 +161,9 @@ def validate(name,                   # type: str
     :param value: the value to check
     :param enforce_not_none: boolean, default True. Whether to enforce that `value` is not None.
     :param equals: an optional value to enforce.
-    :param instance_of: optional type(s) to enforce. If a set of types is provided it is considered alternate types: one
+    :param instance_of: optional type(s) to enforce. If a tuple of types is provided it is considered alternate types: one
         match is enough to succeed. If None, type will not be enforced
-    :param subclass_of: optional type(s) to enforce. If a set of types is provided it is considered alternate types: one
+    :param subclass_of: optional type(s) to enforce. If a tuple of types is provided it is considered alternate types: one
         match is enough to succeed. If None, type will not be enforced
     :param is_in: an optional set of allowed values.
     :param subset_of: an optional superset for the variable
@@ -381,8 +370,8 @@ class validator(Validator):
     def __init__(self,
                  name,              # type: str
                  value,             # type: Any
-                 instance_of=None,  # type: Union[type, Iterable[type]]
-                 subclass_of=None,  # type: Union[type, Iterable[type]]
+                 instance_of=None,  # type: Union[Type, Tuple[Type]]
+                 subclass_of=None,  # type: Union[Type, Tuple[Type]]
                  error_type=None,   # type: Type[ValidationError]
                  help_msg=None,     # type: str
                  **kw_context_args):
@@ -400,9 +389,9 @@ def __init__(self,
 
         :param name: the name of the variable being validated
         :param value: the value being validated
-        :param instance_of: the type(s) to enforce. If a set of types is provided it is considered alternate types:
+        :param instance_of: the type(s) to enforce. If a tuple of types is provided it is considered alternate types:
             one match is enough to succeed. If None, type will not be enforced
-        :param subclass_of: the type(s) to enforce. If a set of types is provided it is considered alternate types: one
+        :param subclass_of: the type(s) to enforce. If a tuple of types is provided it is considered alternate types: one
             match is enough to succeed. If None, type will not be enforced
         :param error_type: a subclass of `ValidationError` to raise in case of validation failure. By default a
             `ValidationError` will be raised with the provided `help_msg`

valid8/tests/test_entry_points_inline.py

@@ -16,9 +16,8 @@ def test_validate_():
     # nominal
     surf = 2
     validate('surface', surf, instance_of=int, min_value=0)
-    validate('surface', surf, instance_of=[int], min_value=0)
-    validate('surface', surf, instance_of={int, str}, min_value=0)
-    validate('surface', surf, instance_of=(t for t in {int, str}), min_value=0)
+    validate('surface', surf, instance_of=(int, ), min_value=0)
+    validate('surface', surf, instance_of=(int, str), min_value=0)
 
     # error wrong value
     surf = -1
@@ -31,7 +30,8 @@ def test_validate_():
     # error wrong type
     surf = 1j
     with pytest.raises(ValidationError) as exc_info:
-        validate('surface', surf, instance_of=(t for t in {int}), min_value=0)
+        # note: we use a length-1 tuple on purpose to see if the error msg takes length into account
+        validate('surface', surf, instance_of=(int, ), min_value=0)
     e = exc_info.value
     assert str(e) == "Error validating [surface=1j]. " \
                      "HasWrongType: Value should be an instance of %s. Wrong value: [1j]." % repr(int)
@@ -236,3 +236,14 @@ def test_function_setter_name_in_valid8_error_message():
 
     from ._test_pep484 import test_function_setter_name_in_valid8_error_message
     test_function_setter_name_in_valid8_error_message()
+
+
+def test_enum_isinstance():
+    """Tests that enum can be used in validate/instance_of"""
+    from enum import Enum
+
+    class MyEnum(Enum):
+        a = 1
+        b = 2
+
+    validate('a', MyEnum.a, instance_of=MyEnum)