from hamcrest import described_as
from hamcrest.core import anything
from hamcrest.core.base_matcher import BaseMatcher
from hamcrest.core.core.allof import AllOf
from hamcrest.core.helpers.wrap_matcher import wrap_matcher as wrap_shortcut
from hamcrest.core.string_description import StringDescription
__author__ = "Chris Rose"
__copyright__ = "Copyright 2011 hamcrest.org"
__license__ = "BSD, see License.txt"
class IsObjectWithProperty(BaseMatcher):
def __init__(self, property_name, value_matcher):
self.property_name = property_name
self.value_matcher = value_matcher
def _matches(self, o):
if o is None:
return False
if not hasattr(o, self.property_name):
return False
value = getattr(o, self.property_name)
return self.value_matcher.matches(value)
def describe_to(self, description):
description.append_text("an object with a property '") \
.append_text(self.property_name) \
.append_text("' matching ") \
.append_description_of(self.value_matcher)
def describe_mismatch(self, item, mismatch_description):
if item is None:
mismatch_description.append_text('was None')
return
if not hasattr(item, self.property_name):
mismatch_description.append_description_of(item) \
.append_text(' did not have the ') \
.append_description_of(self.property_name) \
.append_text(' property')
return
mismatch_description.append_text('property ') \
.append_description_of(self.property_name) \
.append_text(' ')
value = getattr(item, self.property_name)
self.value_matcher.describe_mismatch(value, mismatch_description)
def __str__(self):
d = StringDescription()
self.describe_to(d)
return str(d)
def has_property(name, match=None):
"""Matches if object has a property with a given name whose value satisfies
a given matcher.
:param name: The name of the property.
:param match: Optional matcher to satisfy.
This matcher determines if the evaluated object has a property with a given
name. If no such property is found, ``has_property`` is not satisfied.
If the property is found, its value is passed to a given matcher for
evaluation. If the ``match`` argument is not a matcher, it is implicitly
wrapped in an :py:func:`~hamcrest.core.core.isequal.equal_to` matcher to
check for equality.
If the ``match`` argument is not provided, the
:py:func:`~hamcrest.core.core.isanything.anything` matcher is used so that
``has_property`` is satisfied if a matching property is found.
Examples::
has_property('name', starts_with('J'))
has_property('name', 'Jon')
has_property('name')
"""
if match is None:
match = anything()
return IsObjectWithProperty(name, wrap_shortcut(match))
def has_properties(*keys_valuematchers, **kv_args):
"""Matches if an object has properties satisfying all of a dictionary
of string property names and corresponding value matchers.
:param matcher_dict: A dictionary mapping keys to associated value matchers,
or to expected values for
:py:func:`~hamcrest.core.core.isequal.equal_to` matching.
Note that the keys must be actual keys, not matchers. Any value argument
that is not a matcher is implicitly wrapped in an
:py:func:`~hamcrest.core.core.isequal.equal_to` matcher to check for
equality.
Examples::
has_properties({'foo':equal_to(1), 'bar':equal_to(2)})
has_properties({'foo':1, 'bar':2})
``has_properties`` also accepts a list of keyword arguments:
.. function:: has_properties(keyword1=value_matcher1[, keyword2=value_matcher2[, ...]])
:param keyword1: A keyword to look up.
:param valueMatcher1: The matcher to satisfy for the value, or an expected
value for :py:func:`~hamcrest.core.core.isequal.equal_to` matching.
Examples::
has_properties(foo=equal_to(1), bar=equal_to(2))
has_properties(foo=1, bar=2)
Finally, ``has_properties`` also accepts a list of alternating keys and their
value matchers:
.. function:: has_properties(key1, value_matcher1[, ...])
:param key1: A key (not a matcher) to look up.
:param valueMatcher1: The matcher to satisfy for the value, or an expected
value for :py:func:`~hamcrest.core.core.isequal.equal_to` matching.
Examples::
has_properties('foo', equal_to(1), 'bar', equal_to(2))
has_properties('foo', 1, 'bar', 2)
"""
if len(keys_valuematchers) == 1:
try:
base_dict = keys_valuematchers[0].copy()
for key in base_dict:
base_dict[key] = wrap_shortcut(base_dict[key])
except AttributeError:
raise ValueError('single-argument calls to has_properties must pass a dict as the argument')
else:
if len(keys_valuematchers) % 2:
raise ValueError('has_properties requires key-value pairs')
base_dict = {}
for index in range(int(len(keys_valuematchers) / 2)):
base_dict[keys_valuematchers[2 * index]] = wrap_shortcut(keys_valuematchers[2 * index + 1])
for key, value in kv_args.items():
base_dict[key] = wrap_shortcut(value)
if len(base_dict) > 1:
description = StringDescription().append_text('an object with properties ')
for i, (property_name, property_value_matcher) in enumerate(sorted(base_dict.items())):
description.append_value(property_name).append_text(' matching ').append_description_of(
property_value_matcher)
if i < len(base_dict) - 1:
description.append_text(' and ')
return described_as(str(description),
AllOf(*[has_property(property_name, property_value_matcher)
for property_name, property_value_matcher
in sorted(base_dict.items())],
describe_all_mismatches=True,
describe_matcher_in_mismatch=False))
else:
property_name, property_value_matcher = base_dict.popitem()
return has_property(property_name, property_value_matcher)