author Dustin J. Mitchell <>
Sun, 05 Jun 2016 18:34:31 +0000
changeset 301080 c242defba0dd6a8c50d24c205b7ff975d7bbef35
parent 300752 def3b07ccd145e92a8b5d2062dc437427028ad94
child 303123 22cfff15c199abe0aef76b306603a4acb8c5eded
permissions -rw-r--r--
Bug 1275409: mock{dir,file} too; r=gps This uses a rough form of prefix matching, considering anything that ends in a path separator and appears as a prefix of a file to be a directory. MozReview-Commit-ID: 7FJSxI0fBSA

# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at

from unittest import TextTestRunner as _TestRunner, TestResult as _TestResult
import unittest
import inspect
from StringIO import StringIO
import os

'''Helper to make python unit tests report the way that the Mozilla
unit test infrastructure expects tests to report.


import unittest
import mozunit

if __name__ == '__main__':

class _MozTestResult(_TestResult):
    def __init__(self, stream, descriptions):
        _TestResult.__init__(self) = stream
        self.descriptions = descriptions

    def getDescription(self, test):
        if self.descriptions:
            return test.shortDescription() or str(test)
            return str(test)

    def printStatus(self, status, test, message=''):
        line = "{status} | {file} | {klass}.{test}{sep}{message}".format(
            sep=', ' if message else '',

    def addSuccess(self, test):
        _TestResult.addSuccess(self, test)
        self.printStatus('TEST-PASS', test)

    def addSkip(self, test, reason):
        _TestResult.addSkip(self, test, reason)
        self.printStatus('TEST-SKIP', test)

    def addExpectedFailure(self, test, err):
        _TestResult.addExpectedFailure(self, test, err)
        self.printStatus('TEST-KNOWN-FAIL', test)

    def addUnexpectedSuccess(self, test):
        _TestResult.addUnexpectedSuccess(self, test)
        self.printStatus('TEST-UNEXPECTED-PASS', test)

    def addError(self, test, err):
        _TestResult.addError(self, test, err)
        self.printFail(test, err)"ERROR: {0}".format(self.getDescription(test)))[-1][1])

    def addFailure(self, test, err):
        _TestResult.addFailure(self, test, err)
        self.printFail(test,err)"FAIL: {0}".format(self.getDescription(test)))[-1][1])

    def printFail(self, test, err):
        exctype, value, tb = err
        message = value.message.splitlines()[0] if value.message else 'NO MESSAGE'
        # Skip test runner traceback levels
        while tb and self._is_relevant_tb_level(tb):
            tb = tb.tb_next
        if tb:
            _, ln, _ = inspect.getframeinfo(tb)[:3]
            message = 'line {0}: {1}'.format(ln, message)
        self.printStatus("TEST-UNEXPECTED-FAIL", test, message)

class MozTestRunner(_TestRunner):
    def _makeResult(self):
        return _MozTestResult(, self.descriptions)
    def run(self, test):
        result = self._makeResult()
        return result

class MockedFile(StringIO):
    def __init__(self, context, filename, content = ''):
        self.context = context = filename
        StringIO.__init__(self, content)

    def close(self):
        self.context.files[] = self.getvalue()

    def __enter__(self):
        return self

    def __exit__(self, type, value, traceback):

class MockedOpen(object):
    Context manager diverting the open builtin such that opening files
    can open "virtual" file instances given when creating a MockedOpen.

    with MockedOpen({'foo': 'foo', 'bar': 'bar'}):
        f = open('foo', 'r')

    will thus open the virtual file instance for the file 'foo' to f.

    MockedOpen also masks writes, so that creating or replacing files
    doesn't touch the file system, while subsequently opening the file
    will return the recorded content.

    with MockedOpen():
        f = open('foo', 'w')
    self.assertRaises(Exception,'foo', 'r'))
    def __init__(self, files = {}):
        self.files = {}
        for name, content in files.iteritems():
            self.files[os.path.abspath(name)] = content

    def __call__(self, name, mode = 'r'):
        absname = os.path.abspath(name)
        if 'w' in mode:
            file = MockedFile(self, absname)
        elif absname in self.files:
            file = MockedFile(self, absname, self.files[absname])
        elif 'a' in mode:
            file = MockedFile(self, absname,, 'r').read())
            file =, mode)
        if 'a' in mode:
  , os.SEEK_END)
        return file

    def __enter__(self):
        import __builtin__ =
        self._orig_path_exists = os.path.exists
        self._orig_path_isdir = os.path.isdir
        self._orig_path_isfile = os.path.isfile = self
        os.path.exists = self._wrapped_exists
        os.path.isdir = self._wrapped_isdir
        os.path.isfile = self._wrapped_isfile

    def __exit__(self, type, value, traceback):
        import __builtin__ =
        os.path.exists = self._orig_path_exists
        os.path.isdir = self._orig_path_isdir
        os.path.isfile = self._orig_path_isfile

    def _wrapped_exists(self, p):
        return (self._wrapped_isfile(p) or
                self._wrapped_isdir(p) or

    def _wrapped_isfile(self, p):
        if p in self.files:
            return True

        abspath = os.path.abspath(p)
        if abspath in self.files:
            return True

        return self._orig_path_isfile(p)

    def _wrapped_isdir(self, p):
        p = p if p.endswith(('/', '\\')) else p + os.sep
        if any(f.startswith(p) for f in self.files):
            return True

        abspath = os.path.abspath(p) + os.sep
        if any(f.startswith(abspath) for f in self.files):
            return True

        return self._orig_path_exists(p)

def main(*args, **kwargs):
    unittest.main(testRunner=MozTestRunner(), *args, **kwargs)