def filter_macro(func, *args, **kwargs):
"""
Promotes a function that returns a filter into its own filter type.
Example::
@filter_macro
def String():
return Unicode | Strip | NotEmpty
# You can now use `String` anywhere you would use a regular Filter:
(String | Split(':')).apply('...')
You can also use ``filter_macro`` to create partials, allowing you to
preset one or more initialization arguments::
Minor = filter_macro(Max, max_value=18, inclusive=False)
Minor(inclusive=True).apply(18)
"""
filter_partial = partial(func, *args, **kwargs)
class FilterMacroMeta(FilterMeta):
@staticmethod
def __new__(mcs, name, bases, attrs):
# This is as close as we can get to running
# ``update_wrapper`` on a type.
for attr in WRAPPER_ASSIGNMENTS:
if hasattr(func, attr):
attrs[attr] = getattr(func, attr)
# Note that we ignore the ``name`` argument, passing in
# ``func.__name__`` instead.
return super(FilterMacroMeta, mcs)\
.__new__(mcs, func.__name__, bases, attrs)
def __call__(cls, *runtime_args, **runtime_kwargs):
return filter_partial(*runtime_args, **runtime_kwargs)
class FilterMacro(with_metaclass(FilterMacroMeta, FilterMacroType)):
# This method will probably never get called due to overloaded
# ``__call__`` in the metaclass, but just in case, we'll include
# it because it is an abstract method in `BaseFilter`.
def _apply(self, value):
# noinspection PyProtectedMember
return self.__class__()._apply(value)
return FilterMacro
python类with_metaclass()的实例源码
reflection_test.py 文件源码
项目：Vector-Tiles-Reader-QGIS-Plugin
作者: geometalab
项目源码
文件源码
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def testDescriptorProtoSupport(self):
# Hand written descriptors/reflection are only supported by the pure-Python
# implementation of the API.
if api_implementation.Type() != 'python':
return
def AddDescriptorField(proto, field_name, field_type):
AddDescriptorField.field_index += 1
new_field = proto.field.add()
new_field.name = field_name
new_field.type = field_type
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_OPTIONAL
AddDescriptorField.field_index = 0
desc_proto = descriptor_pb2.DescriptorProto()
desc_proto.name = 'Car'
fdp = descriptor_pb2.FieldDescriptorProto
AddDescriptorField(desc_proto, 'name', fdp.TYPE_STRING)
AddDescriptorField(desc_proto, 'year', fdp.TYPE_INT64)
AddDescriptorField(desc_proto, 'automatic', fdp.TYPE_BOOL)
AddDescriptorField(desc_proto, 'price', fdp.TYPE_DOUBLE)
# Add a repeated field
AddDescriptorField.field_index += 1
new_field = desc_proto.field.add()
new_field.name = 'owners'
new_field.type = fdp.TYPE_STRING
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_REPEATED
desc = descriptor.MakeDescriptor(desc_proto)
self.assertTrue('name' in desc.fields_by_name)
self.assertTrue('year' in desc.fields_by_name)
self.assertTrue('automatic' in desc.fields_by_name)
self.assertTrue('price' in desc.fields_by_name)
self.assertTrue('owners' in desc.fields_by_name)
class CarMessage(six.with_metaclass(reflection.GeneratedProtocolMessageType, message.Message)):
DESCRIPTOR = desc
prius = CarMessage()
prius.name = 'prius'
prius.year = 2010
prius.automatic = True
prius.price = 25134.75
prius.owners.extend(['bob', 'susan'])
serialized_prius = prius.SerializeToString()
new_prius = reflection.ParseMessage(desc, serialized_prius)
self.assertTrue(new_prius is not prius)
self.assertEqual(prius, new_prius)
# these are unnecessary assuming message equality works as advertised but
# explicitly check to be safe since we're mucking about in metaclass foo
self.assertEqual(prius.name, new_prius.name)
self.assertEqual(prius.year, new_prius.year)
self.assertEqual(prius.automatic, new_prius.automatic)
self.assertEqual(prius.price, new_prius.price)
self.assertEqual(prius.owners, new_prius.owners)
def testDescriptorProtoSupport(self):
# Hand written descriptors/reflection are only supported by the pure-Python
# implementation of the API.
if api_implementation.Type() != 'python':
return
def AddDescriptorField(proto, field_name, field_type):
AddDescriptorField.field_index += 1
new_field = proto.field.add()
new_field.name = field_name
new_field.type = field_type
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_OPTIONAL
AddDescriptorField.field_index = 0
desc_proto = descriptor_pb2.DescriptorProto()
desc_proto.name = 'Car'
fdp = descriptor_pb2.FieldDescriptorProto
AddDescriptorField(desc_proto, 'name', fdp.TYPE_STRING)
AddDescriptorField(desc_proto, 'year', fdp.TYPE_INT64)
AddDescriptorField(desc_proto, 'automatic', fdp.TYPE_BOOL)
AddDescriptorField(desc_proto, 'price', fdp.TYPE_DOUBLE)
# Add a repeated field
AddDescriptorField.field_index += 1
new_field = desc_proto.field.add()
new_field.name = 'owners'
new_field.type = fdp.TYPE_STRING
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_REPEATED
desc = descriptor.MakeDescriptor(desc_proto)
self.assertTrue('name' in desc.fields_by_name)
self.assertTrue('year' in desc.fields_by_name)
self.assertTrue('automatic' in desc.fields_by_name)
self.assertTrue('price' in desc.fields_by_name)
self.assertTrue('owners' in desc.fields_by_name)
class CarMessage(six.with_metaclass(reflection.GeneratedProtocolMessageType, message.Message)):
DESCRIPTOR = desc
prius = CarMessage()
prius.name = 'prius'
prius.year = 2010
prius.automatic = True
prius.price = 25134.75
prius.owners.extend(['bob', 'susan'])
serialized_prius = prius.SerializeToString()
new_prius = reflection.ParseMessage(desc, serialized_prius)
self.assertTrue(new_prius is not prius)
self.assertEqual(prius, new_prius)
# these are unnecessary assuming message equality works as advertised but
# explicitly check to be safe since we're mucking about in metaclass foo
self.assertEqual(prius.name, new_prius.name)
self.assertEqual(prius.year, new_prius.year)
self.assertEqual(prius.automatic, new_prius.automatic)
self.assertEqual(prius.price, new_prius.price)
self.assertEqual(prius.owners, new_prius.owners)
def testDescriptorProtoSupport(self):
# Hand written descriptors/reflection are only supported by the pure-Python
# implementation of the API.
if api_implementation.Type() != 'python':
return
def AddDescriptorField(proto, field_name, field_type):
AddDescriptorField.field_index += 1
new_field = proto.field.add()
new_field.name = field_name
new_field.type = field_type
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_OPTIONAL
AddDescriptorField.field_index = 0
desc_proto = descriptor_pb2.DescriptorProto()
desc_proto.name = 'Car'
fdp = descriptor_pb2.FieldDescriptorProto
AddDescriptorField(desc_proto, 'name', fdp.TYPE_STRING)
AddDescriptorField(desc_proto, 'year', fdp.TYPE_INT64)
AddDescriptorField(desc_proto, 'automatic', fdp.TYPE_BOOL)
AddDescriptorField(desc_proto, 'price', fdp.TYPE_DOUBLE)
# Add a repeated field
AddDescriptorField.field_index += 1
new_field = desc_proto.field.add()
new_field.name = 'owners'
new_field.type = fdp.TYPE_STRING
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_REPEATED
desc = descriptor.MakeDescriptor(desc_proto)
self.assertTrue('name' in desc.fields_by_name)
self.assertTrue('year' in desc.fields_by_name)
self.assertTrue('automatic' in desc.fields_by_name)
self.assertTrue('price' in desc.fields_by_name)
self.assertTrue('owners' in desc.fields_by_name)
class CarMessage(six.with_metaclass(reflection.GeneratedProtocolMessageType, message.Message)):
DESCRIPTOR = desc
prius = CarMessage()
prius.name = 'prius'
prius.year = 2010
prius.automatic = True
prius.price = 25134.75
prius.owners.extend(['bob', 'susan'])
serialized_prius = prius.SerializeToString()
new_prius = reflection.ParseMessage(desc, serialized_prius)
self.assertTrue(new_prius is not prius)
self.assertEqual(prius, new_prius)
# these are unnecessary assuming message equality works as advertised but
# explicitly check to be safe since we're mucking about in metaclass foo
self.assertEqual(prius.name, new_prius.name)
self.assertEqual(prius.year, new_prius.year)
self.assertEqual(prius.automatic, new_prius.automatic)
self.assertEqual(prius.price, new_prius.price)
self.assertEqual(prius.owners, new_prius.owners)
def testDescriptorProtoSupport(self):
# Hand written descriptors/reflection are only supported by the pure-Python
# implementation of the API.
if api_implementation.Type() != 'python':
return
def AddDescriptorField(proto, field_name, field_type):
AddDescriptorField.field_index += 1
new_field = proto.field.add()
new_field.name = field_name
new_field.type = field_type
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_OPTIONAL
AddDescriptorField.field_index = 0
desc_proto = descriptor_pb2.DescriptorProto()
desc_proto.name = 'Car'
fdp = descriptor_pb2.FieldDescriptorProto
AddDescriptorField(desc_proto, 'name', fdp.TYPE_STRING)
AddDescriptorField(desc_proto, 'year', fdp.TYPE_INT64)
AddDescriptorField(desc_proto, 'automatic', fdp.TYPE_BOOL)
AddDescriptorField(desc_proto, 'price', fdp.TYPE_DOUBLE)
# Add a repeated field
AddDescriptorField.field_index += 1
new_field = desc_proto.field.add()
new_field.name = 'owners'
new_field.type = fdp.TYPE_STRING
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_REPEATED
desc = descriptor.MakeDescriptor(desc_proto)
self.assertTrue('name' in desc.fields_by_name)
self.assertTrue('year' in desc.fields_by_name)
self.assertTrue('automatic' in desc.fields_by_name)
self.assertTrue('price' in desc.fields_by_name)
self.assertTrue('owners' in desc.fields_by_name)
class CarMessage(six.with_metaclass(reflection.GeneratedProtocolMessageType, message.Message)):
DESCRIPTOR = desc
prius = CarMessage()
prius.name = 'prius'
prius.year = 2010
prius.automatic = True
prius.price = 25134.75
prius.owners.extend(['bob', 'susan'])
serialized_prius = prius.SerializeToString()
new_prius = reflection.ParseMessage(desc, serialized_prius)
self.assertTrue(new_prius is not prius)
self.assertEqual(prius, new_prius)
# these are unnecessary assuming message equality works as advertised but
# explicitly check to be safe since we're mucking about in metaclass foo
self.assertEqual(prius.name, new_prius.name)
self.assertEqual(prius.year, new_prius.year)
self.assertEqual(prius.automatic, new_prius.automatic)
self.assertEqual(prius.price, new_prius.price)
self.assertEqual(prius.owners, new_prius.owners)
def testDescriptorProtoSupport(self):
# Hand written descriptors/reflection are only supported by the pure-Python
# implementation of the API.
if api_implementation.Type() != 'python':
return
def AddDescriptorField(proto, field_name, field_type):
AddDescriptorField.field_index += 1
new_field = proto.field.add()
new_field.name = field_name
new_field.type = field_type
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_OPTIONAL
AddDescriptorField.field_index = 0
desc_proto = descriptor_pb2.DescriptorProto()
desc_proto.name = 'Car'
fdp = descriptor_pb2.FieldDescriptorProto
AddDescriptorField(desc_proto, 'name', fdp.TYPE_STRING)
AddDescriptorField(desc_proto, 'year', fdp.TYPE_INT64)
AddDescriptorField(desc_proto, 'automatic', fdp.TYPE_BOOL)
AddDescriptorField(desc_proto, 'price', fdp.TYPE_DOUBLE)
# Add a repeated field
AddDescriptorField.field_index += 1
new_field = desc_proto.field.add()
new_field.name = 'owners'
new_field.type = fdp.TYPE_STRING
new_field.number = AddDescriptorField.field_index
new_field.label = descriptor_pb2.FieldDescriptorProto.LABEL_REPEATED
desc = descriptor.MakeDescriptor(desc_proto)
self.assertTrue('name' in desc.fields_by_name)
self.assertTrue('year' in desc.fields_by_name)
self.assertTrue('automatic' in desc.fields_by_name)
self.assertTrue('price' in desc.fields_by_name)
self.assertTrue('owners' in desc.fields_by_name)
class CarMessage(six.with_metaclass(reflection.GeneratedProtocolMessageType, message.Message)):
DESCRIPTOR = desc
prius = CarMessage()
prius.name = 'prius'
prius.year = 2010
prius.automatic = True
prius.price = 25134.75
prius.owners.extend(['bob', 'susan'])
serialized_prius = prius.SerializeToString()
new_prius = reflection.ParseMessage(desc, serialized_prius)
self.assertTrue(new_prius is not prius)
self.assertEqual(prius, new_prius)
# these are unnecessary assuming message equality works as advertised but
# explicitly check to be safe since we're mucking about in metaclass foo
self.assertEqual(prius.name, new_prius.name)
self.assertEqual(prius.year, new_prius.year)
self.assertEqual(prius.automatic, new_prius.automatic)
self.assertEqual(prius.price, new_prius.price)
self.assertEqual(prius.owners, new_prius.owners)
