keystone/keystone/tests/matchers.py
David Stanek c4ec6eb424 Fixes an issue with the XMLEquals matcher
The matcher implementation would fail to match two documents that are
semantically equivalent, but sibling elements appear in different
document order.

Change-Id: I99dc6401e73be4c61bb265c3258b6245f2e7bb34
Closes-bug: #1347891
2014-08-14 02:28:28 +00:00

92 lines
3.1 KiB
Python

# Copyright 2013 OpenStack Foundation
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from lxml import etree
from testtools import matchers
class XMLEquals(object):
"""Parses two XML documents from strings and compares the results.
"""
def __init__(self, expected):
self.expected = expected
def __str__(self):
return "%s(%r)" % (self.__class__.__name__, self.expected)
def match(self, other):
def xml_element_equals(expected_doc, observed_doc):
"""Tests whether two XML documents are equivalent.
This is a recursive algorithm that operates on each element in
the hierarchy. Siblings are sorted before being checked to
account for two semantically equivalent documents where siblings
appear in different document order.
The sorting algorithm is a little weak in that it could fail for
documents where siblings at a given level are the same, but have
different children.
"""
if expected_doc.tag != observed_doc.tag:
return False
if expected_doc.attrib != observed_doc.attrib:
return False
def _sorted_children(doc):
return sorted(doc.getchildren(), key=lambda el: el.tag)
expected_children = _sorted_children(expected_doc)
observed_children = _sorted_children(observed_doc)
if len(expected_children) != len(observed_children):
return False
for expected_el, observed_el in zip(expected_children,
observed_children):
if not xml_element_equals(expected_el, observed_el):
return False
return True
parser = etree.XMLParser(remove_blank_text=True)
expected_doc = etree.fromstring(self.expected.strip(), parser)
observed_doc = etree.fromstring(other.strip(), parser)
if xml_element_equals(expected_doc, observed_doc):
return
return XMLMismatch(self.expected, other)
class XMLMismatch(matchers.Mismatch):
def __init__(self, expected, other):
self.expected = expected
self.other = other
def describe(self):
def pretty_xml(xml):
parser = etree.XMLParser(remove_blank_text=True)
doc = etree.fromstring(xml.strip(), parser)
return (etree.tostring(doc, encoding='utf-8', pretty_print=True)
.decode('utf-8'))
return 'expected =\n%s\nactual =\n%s' % (
pretty_xml(self.expected), pretty_xml(self.other))