Python abc.abstractmethod() Examples

def test_ignores_return_in_abstract_method_sphinx(self):
        """Example of an abstract method documenting the return type that an
        implementation should return.
        """
        node = astroid.extract_node("""
        import abc
        class Foo(object):
            @abc.abstractmethod
            def foo(self): #@
                '''docstring ...

                :returns: Ten
                :rtype: int
                '''
                return 10
        """)
        with self.assertNoMessages():
            self.checker.visit_functiondef(node) 

def test_ignores_return_in_abstract_method_google(self):
        """Example of an abstract method documenting the return type that an
        implementation should return.
        """
        node = astroid.extract_node("""
        import abc
        class Foo(object):
            @abc.abstractmethod
            def foo(self): #@
                '''docstring ...

                Returns:
                    int: Ten
                '''
                return 10
        """)
        with self.assertNoMessages():
            self.checker.visit_functiondef(node) 

def test_cache_leak(self):
        # See issue #2521.
        class A(object):
            __metaclass__ = abc.ABCMeta
            @abc.abstractmethod
            def f(self):
                pass
        class C(A):
            def f(self):
                A.f(self)
        r = weakref.ref(C)
        # Trigger cache.
        C().f()
        del C
        test_support.gc_collect()
        self.assertEqual(r(), None) 

def test_ignores_return_in_abstract_method_numpy(self):
        """Example of an abstract method documenting the return type that an
        implementation should return.
        """
        node = astroid.extract_node("""
        import abc
        class Foo(object):
            @abc.abstractmethod
            def foo(self): #@
                '''docstring ...

                Returns
                -------
                int
                    Ten
                '''
                return 10
        """)
        with self.assertNoMessages():
            self.checker.visit_functiondef(node) 

def test_ignores_return_in_abstract_method_sphinx(self):
        """Example of an abstract method documenting the return type that an
        implementation should return.
        """
        node = astroid.extract_node("""
        import abc
        class Foo(object):
            @abc.abstractmethod
            def foo(self): #@
                '''docstring ...

                :returns: Ten
                :rtype: int
                '''
                return 10
        """)
        with self.assertNoMessages():
            self.checker.visit_functiondef(node) 

def test_ignores_return_in_abstract_method_google(self):
        """Example of an abstract method documenting the return type that an
        implementation should return.
        """
        node = astroid.extract_node("""
        import abc
        class Foo(object):
            @abc.abstractmethod
            def foo(self): #@
                '''docstring ...

                Returns:
                    int: Ten
                '''
                return 10
        """)
        with self.assertNoMessages():
            self.checker.visit_functiondef(node) 

def test_abstractproperty_basics(self):
        @property
        @abc.abstractmethod
        def foo(self): pass
        self.assertTrue(foo.__isabstractmethod__)
        def bar(self): pass
        self.assertFalse(getattr(bar, "__isabstractmethod__", False))

        class C(metaclass=abc.ABCMeta):
            @property
            @abc.abstractmethod
            def foo(self): return 3
        self.assertRaises(TypeError, C)
        class D(C):
            @C.foo.getter
            def foo(self): return super().foo
        self.assertEqual(D().foo, 3) 

def test_abstractproperty_basics(self):
        @property
        @abc.abstractmethod
        def foo(self): pass
        self.assertTrue(foo.__isabstractmethod__)
        def bar(self): pass
        self.assertFalse(getattr(bar, "__isabstractmethod__", False))

        class C(metaclass=abc.ABCMeta):
            @property
            @abc.abstractmethod
            def foo(self): return 3
        self.assertRaises(TypeError, C)
        class D(C):
            @C.foo.getter
            def foo(self): return super().foo
        self.assertEqual(D().foo, 3) 

def test_abstract_method(self) -> None:
        class A(icontract.DBC):
            @icontract.ensure(lambda result: result < 100)
            @abc.abstractmethod
            def func(self) -> int:
                pass

        class B(A):
            def func(self) -> int:
                return 1000

        b = B()
        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            b.func()
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual("result < 100: result was 1000", tests.error.wo_mandatory_location(str(violation_error))) 

def test_abstractclassmethod_basics(self):
        @classmethod
        @abc.abstractmethod
        def foo(cls): pass
        self.assertTrue(foo.__isabstractmethod__)
        @classmethod
        def bar(cls): pass
        self.assertFalse(getattr(bar, "__isabstractmethod__", False))

        class C(metaclass=abc.ABCMeta):
            @classmethod
            @abc.abstractmethod
            def foo(cls): return cls.__name__
        self.assertRaises(TypeError, C)
        class D(C):
            @classmethod
            def foo(cls): return super().foo()
        self.assertEqual(D.foo(), 'D')
        self.assertEqual(D().foo(), 'D') 

def test_cache_leak(self):
        # See issue #2521.
        class A(object):
            __metaclass__ = abc.ABCMeta
            @abc.abstractmethod
            def f(self):
                pass
        class C(A):
            def f(self):
                A.f(self)
        r = weakref.ref(C)
        # Trigger cache.
        C().f()
        del C
        test_support.gc_collect()
        self.assertEqual(r(), None) 

def test_abstract_method_not_implemented(self) -> None:
        # pylint: disable=abstract-method
        class A(icontract.DBC):
            @icontract.ensure(lambda result: result < 100)
            @abc.abstractmethod
            def func(self) -> int:
                pass

        class B(A):
            pass

        type_err = None  # type: Optional[TypeError]
        try:
            _ = B()  # type: ignore
        except TypeError as err:
            type_err = err

        self.assertIsNotNone(type_err)
        self.assertEqual("Can't instantiate abstract class B with abstract methods func", str(type_err)) 

def test_abstract_method(self) -> None:
        class A(icontract.DBC):
            @icontract.require(lambda x: x > 0)
            @abc.abstractmethod
            def func(self, x: int) -> int:
                pass

        class B(A):
            def func(self, x: int) -> int:
                return 1000

        b = B()
        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            b.func(x=-1)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual("x > 0: x was -1", tests.error.wo_mandatory_location(str(violation_error))) 

def test_abstractclassmethod_basics(self):
        @classmethod
        @abc.abstractmethod
        def foo(cls): pass
        self.assertTrue(foo.__isabstractmethod__)
        @classmethod
        def bar(cls): pass
        self.assertFalse(getattr(bar, "__isabstractmethod__", False))

        class C(metaclass=abc.ABCMeta):
            @classmethod
            @abc.abstractmethod
            def foo(cls): return cls.__name__
        self.assertRaises(TypeError, C)
        class D(C):
            @classmethod
            def foo(cls): return super().foo()
        self.assertEqual(D.foo(), 'D')
        self.assertEqual(D().foo(), 'D') 

def test_postcondition_in_abstract_class_method(self) -> None:
        class Abstract(icontract.DBC):
            @classmethod
            @abc.abstractmethod
            @icontract.ensure(lambda result: result != 0)
            def some_func(cls: Type['Abstract'], x: int) -> int:
                pass

        class SomeClass(Abstract):
            @classmethod
            def some_func(cls: Type['SomeClass'], x: int) -> int:
                return x

        result = SomeClass.some_func(x=1)
        self.assertEqual(1, result)

        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            _ = SomeClass.some_func(x=0)
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual('result != 0: result was 0', tests.error.wo_mandatory_location(str(violation_error))) 

def test_abstractmethod_register(self):
        class Abstract(abc.ABCMeta):

            @singledispatchmethod
            @abc.abstractmethod
            def add(self, x, y):
                pass

        assert Abstract.add.__isabstractmethod__ is True 

def test_cache_leak(self):
        # See issue #2521.
        class A(object):
            __metaclass__ = abc.ABCMeta
            @abc.abstractmethod
            def f(self):
                pass
        class C(A):
            def f(self):
                A.f(self)
        r = weakref.ref(C)
        # Trigger cache.
        C().f()
        del C
        test_support.gc_collect()
        self.assertEqual(r(), None) 

def setUpClass(cls):
        FinalABCMeta = final_meta_factory(ABCMeta)

        class ABCWithFinal(with_metaclass(FinalABCMeta, object)):
            a = final('ABCWithFinal: a')
            b = 'ABCWithFinal: b'

            @final
            def f(self):
                return 'ABCWithFinal: f'

            def g(self):
                return 'ABCWithFinal: g'

            @abstractmethod
            def h(self):
                raise NotImplementedError('h')

        cls.class_ = ABCWithFinal 

def test_cache_leak(self):
        # See issue #2521.
        class A(object):
            __metaclass__ = abc.ABCMeta
            @abc.abstractmethod
            def f(self):
                pass
        class C(A):
            def f(self):
                A.f(self)
        r = weakref.ref(C)
        # Trigger cache.
        C().f()
        del C
        test_support.gc_collect()
        self.assertEqual(r(), None) 

def get_epoch_snapshot(self, epoch):
        """
        Probably will be overridden by each algorithm
        """
        data_to_save = dict(
            epoch=epoch,
            exploration_policy=self.exploration_policy,
        )
        if self.save_environment:
            data_to_save['env'] = self.training_env
        return data_to_save
    
    
    # @abc.abstractmethod
    # def load_snapshot(self, snapshot):
    #     """
    #     Should be implemented on a per algorithm basis
    #     taking into consideration the particular
    #     get_epoch_snapshot implementation for the algorithm
    #     """
    #     pass 

def get_epoch_snapshot(self, epoch):
        """
        Probably will be overridden by each algorithm
        """
        data_to_save = dict(
            epoch=epoch,
            exploration_policy=self.exploration_policy,
        )
        if self.save_environment:
            data_to_save['env'] = self.training_env
        return data_to_save
    
    # @abc.abstractmethod
    # def load_snapshot(self, snapshot):
    #     """
    #     Should be implemented on a per algorithm basis
    #     taking into consideration the particular
    #     get_epoch_snapshot implementation for the algorithm
    #     """
    #     pass 

def __init__(self, protocol, chunk_size=None):
        self.chunk_size = chunk_size or CHUNK_SIZE  # The number of items to send in a single request
        if not isinstance(self.chunk_size, int):
            raise ValueError("'chunk_size' %r must be an integer" % chunk_size)
        if self.chunk_size < 1:
            raise ValueError("'chunk_size' must be a positive number")
        self.protocol = protocol

    # The following two methods are the minimum required to be implemented by subclasses, but the name and number of
    # kwargs differs between services. Therefore, we cannot make these methods abstract.

    # @abc.abstractmethod
    # def call(self, **kwargs):
    #     raise NotImplementedError()

    # @abc.abstractmethod
    # def get_payload(self, **kwargs):
    #     raise NotImplementedError() 

def __store_annotations__(self,zooniverse_id,max_users=float("inf"),expert_markings=False):
        """
        override the parent method so that we can apply ROIs
        read through and return all of the relevant annotations associated with the given zooniverse_id
        :param zooniverse_id: id of the subject
        :param max_users: maximum number of classifications to read in
        :param expert_markings: do we want to read in markings from experts - either yes or no, shouldn't mix
        :return:
        """
        if not(zooniverse_id in self.roi_dict):
            self.roi_dict[zooniverse_id] = self.__get_roi__(zooniverse_id)

        self.current_roi = self.roi_dict[zooniverse_id]
        OuroborosAPI.__store_annotations__(self,zooniverse_id,max_users,expert_markings)

        self.current_roi = None

    # @abc.abstractmethod
    # def __classification_to_markings__(self,classification,roi):
    #     """
    #     This is the main function projects will have to override - given a set of annotations, we need to return the list
    #     of all markings in that annotation
    #     """
    #     return [] 

def convert(self, operator: OperatorBase) -> OperatorBase:
        r"""
        Convert a ``SummedOp`` into a ``ComposedOp`` or ``CircuitOp`` representing an
        approximation of e^-i*``op_sum``.

        Args:
            operator: The ``SummedOp`` to evolve.

        Returns:
            The Operator approximating op_sum's evolution.

        Raises:
            TypeError: A non-SummedOps Operator is passed into ``convert``.

        """
        raise NotImplementedError

    # TODO @abstractmethod - trotter_error_bound 

def test_abstractproperty_basics(self):
        @property
        @abc.abstractmethod
        def foo(self): pass
        self.assertTrue(foo.__isabstractmethod__)
        def bar(self): pass
        self.assertFalse(getattr(bar, "__isabstractmethod__", False))

        class C(metaclass=abc.ABCMeta):
            @property
            @abc.abstractmethod
            def foo(self): return 3
        self.assertRaises(TypeError, C)
        class D(C):
            @C.foo.getter
            def foo(self): return super().foo
        self.assertEqual(D().foo, 3) 

def test_abstractclassmethod_basics(self):
        @classmethod
        @abc.abstractmethod
        def foo(cls): pass
        self.assertTrue(foo.__isabstractmethod__)
        @classmethod
        def bar(cls): pass
        self.assertFalse(getattr(bar, "__isabstractmethod__", False))

        class C(metaclass=abc.ABCMeta):
            @classmethod
            @abc.abstractmethod
            def foo(cls): return cls.__name__
        self.assertRaises(TypeError, C)
        class D(C):
            @classmethod
            def foo(cls): return super().foo()
        self.assertEqual(D.foo(), 'D')
        self.assertEqual(D().foo(), 'D') 

def setUpClass(cls):
        FinalABCMeta = compose_types(FinalMeta, ABCMeta)

        class ABCWithFinal(with_metaclass(FinalABCMeta, object)):
            a = final('ABCWithFinal: a')
            b = 'ABCWithFinal: b'

            @final
            def f(self):
                return 'ABCWithFinal: f'

            def g(self):
                return 'ABCWithFinal: g'

            @abstractmethod
            def h(self):
                raise NotImplementedError('h')

        cls.class_ = ABCWithFinal 

def _abstract_property() -> Any:
  """Returns an abstract property for use in an ABC abstract class."""
  return abc.abstractmethod(lambda: None) 

def test_cannot_instantiate_subclass(self):
        """
        Tests that you cannot create an instance of a subclass
        that does not implement the abstractmethod h.
        """
        class AbstractSubClass(self.class_):
            pass

        with self.assertRaises(TypeError):
            AbstractSubClass() 

def test_with_abstract_method(self) -> None:
        @icontract.invariant(lambda self: self.x > 0)
        class A(icontract.DBC):
            def __init__(self) -> None:
                self.x = 10

            @abc.abstractmethod
            def func(self) -> None:
                pass

            def __repr__(self) -> str:
                return "instance of A"

        class B(A):
            def func(self) -> None:
                self.x = -1

            def __repr__(self) -> str:
                return "instance of B"

        b = B()
        violation_error = None  # type: Optional[icontract.ViolationError]
        try:
            b.func()
        except icontract.ViolationError as err:
            violation_error = err

        self.assertIsNotNone(violation_error)
        self.assertEqual("self.x > 0:\n"
                         "self was instance of B\n"
                         "self.x was -1", tests.error.wo_mandatory_location(str(violation_error)))