from hamcrest.core.base_matcher import BaseMatcher
from hamcrest.core.helpers.hasmethod import hasmethod
from hamcrest.core.helpers.wrap_matcher import wrap_matcher
__author__ = "Jon Reid"
__copyright__ = "Copyright 2011 hamcrest.org"
__license__ = "BSD, see License.txt"
class HasLength(BaseMatcher):
def __init__(self, len_matcher):
self.len_matcher = len_matcher
def _matches(self, item):
if not hasmethod(item, '__len__'):
return False
return self.len_matcher.matches(len(item))
def describe_mismatch(self, item, mismatch_description):
super(HasLength, self).describe_mismatch(item, mismatch_description)
if hasmethod(item, '__len__'):
mismatch_description.append_text(' with length of ') \
.append_description_of(len(item))
def describe_to(self, description):
description.append_text('an object with length of ') \
.append_description_of(self.len_matcher)
[docs]def has_length(match):
"""Matches if ``len(item)`` satisfies a given matcher.
:param match: The matcher to satisfy, or an expected value for
:py:func:`~hamcrest.core.core.isequal.equal_to` matching.
This matcher invokes the :py:func:`len` function on the evaluated object to
get its length, passing the result 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.
Examples::
has_length(greater_than(6))
has_length(5)
"""
return HasLength(wrap_matcher(match))