Check in the thirdparty libs needed for webkitpy.

Tools/Scripts/webkitpy/thirdparty/unittest2/case.py

Index: Tools/Scripts/webkitpy/thirdparty/unittest2/case.py
diff --git a/Tools/Scripts/webkitpy/thirdparty/unittest2/case.py b/Tools/Scripts/webkitpy/thirdparty/unittest2/case.py
new file mode 100644
index 0000000000000000000000000000000000000000..105914bb58bee79e2c7105d36655197ac4cce137
--- /dev/null
+++ b/Tools/Scripts/webkitpy/thirdparty/unittest2/case.py
@@ -0,0 +1,1084 @@
+"""Test case implementation"""
+
+import sys
+import difflib
+import pprint
+import re
+import unittest
+import warnings
+
+from unittest2 import result
+from unittest2.util import (
+    safe_repr, safe_str, strclass,
+    unorderable_list_difference
+)
+
+from unittest2.compatibility import wraps
+
+__unittest = True
+
+
+DIFF_OMITTED = ('\nDiff is %s characters long. '
+                 'Set self.maxDiff to None to see it.')
+
+class SkipTest(Exception):
+    """
+    Raise this exception in a test to skip it.
+
+    Usually you can use TestResult.skip() or one of the skipping decorators
+    instead of raising this directly.
+    """
+
+class _ExpectedFailure(Exception):
+    """
+    Raise this when a test is expected to fail.
+
+    This is an implementation detail.
+    """
+
+    def __init__(self, exc_info):
+        # can't use super because Python 2.4 exceptions are old style
+        Exception.__init__(self)
+        self.exc_info = exc_info
+
+class _UnexpectedSuccess(Exception):
+    """
+    The test was supposed to fail, but it didn't!
+    """
+
+def _id(obj):
+    return obj
+
+def skip(reason):
+    """
+    Unconditionally skip a test.
+    """
+    def decorator(test_item):
+        if not (isinstance(test_item, type) and issubclass(test_item, TestCase)):
+            @wraps(test_item)
+            def skip_wrapper(*args, **kwargs):
+                raise SkipTest(reason)
+            test_item = skip_wrapper
+        
+        test_item.__unittest_skip__ = True
+        test_item.__unittest_skip_why__ = reason
+        return test_item
+    return decorator
+
+def skipIf(condition, reason):
+    """
+    Skip a test if the condition is true.
+    """
+    if condition:
+        return skip(reason)
+    return _id
+
+def skipUnless(condition, reason):
+    """
+    Skip a test unless the condition is true.
+    """
+    if not condition:
+        return skip(reason)
+    return _id
+
+
+def expectedFailure(func):
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        try:
+            func(*args, **kwargs)
+        except Exception:
+            raise _ExpectedFailure(sys.exc_info())
+        raise _UnexpectedSuccess
+    return wrapper
+
+
+class _AssertRaisesContext(object):
+    """A context manager used to implement TestCase.assertRaises* methods."""
+
+    def __init__(self, expected, test_case, expected_regexp=None):
+        self.expected = expected
+        self.failureException = test_case.failureException
+        self.expected_regexp = expected_regexp
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_value, tb):
+        if exc_type is None:
+            try:
+                exc_name = self.expected.__name__
+            except AttributeError:
+                exc_name = str(self.expected)
+            raise self.failureException(
+                "%s not raised" % (exc_name,))
+        if not issubclass(exc_type, self.expected):
+            # let unexpected exceptions pass through
+            return False
+        self.exception = exc_value # store for later retrieval
+        if self.expected_regexp is None:
+            return True
+
+        expected_regexp = self.expected_regexp
+        if isinstance(expected_regexp, basestring):
+            expected_regexp = re.compile(expected_regexp)
+        if not expected_regexp.search(str(exc_value)):
+            raise self.failureException('"%s" does not match "%s"' %
+                     (expected_regexp.pattern, str(exc_value)))
+        return True
+
+
+class _TypeEqualityDict(object):
+    
+    def __init__(self, testcase):
+        self.testcase = testcase
+        self._store = {}
+    
+    def __setitem__(self, key, value):
+        self._store[key] = value
+    
+    def __getitem__(self, key):
+        value = self._store[key]
+        if isinstance(value, basestring):
+            return getattr(self.testcase, value)
+        return value
+    
+    def get(self, key, default=None):
+        if key in self._store:
+            return self[key]
+        return default
+
+
+class TestCase(unittest.TestCase):
+    """A class whose instances are single test cases.
+
+    By default, the test code itself should be placed in a method named
+    'runTest'.
+
+    If the fixture may be used for many test cases, create as
+    many test methods as are needed. When instantiating such a TestCase
+    subclass, specify in the constructor arguments the name of the test method
+    that the instance is to execute.
+
+    Test authors should subclass TestCase for their own tests. Construction
+    and deconstruction of the test's environment ('fixture') can be
+    implemented by overriding the 'setUp' and 'tearDown' methods respectively.
+
+    If it is necessary to override the __init__ method, the base class
+    __init__ method must always be called. It is important that subclasses
+    should not change the signature of their __init__ method, since instances
+    of the classes are instantiated automatically by parts of the framework
+    in order to be run.
+    """
+
+    # This attribute determines which exception will be raised when
+    # the instance's assertion methods fail; test methods raising this
+    # exception will be deemed to have 'failed' rather than 'errored'
+
+    failureException = AssertionError
+
+    # This attribute sets the maximum length of a diff in failure messages
+    # by assert methods using difflib. It is looked up as an instance attribute
+    # so can be configured by individual tests if required.
+
+    maxDiff = 80*8
+
+    # This attribute determines whether long messages (including repr of
+    # objects used in assert methods) will be printed on failure in *addition*
+    # to any explicit message passed.
+
+    longMessage = True
+    
+    # Attribute used by TestSuite for classSetUp
+    
+    _classSetupFailed = False
+
+    def __init__(self, methodName='runTest'):
+        """Create an instance of the class that will use the named test
+           method when executed. Raises a ValueError if the instance does
+           not have a method with the specified name.
+        """
+        self._testMethodName = methodName
+        self._resultForDoCleanups = None
+        try:
+            testMethod = getattr(self, methodName)
+        except AttributeError:
+            raise ValueError("no such test method in %s: %s" % \
+                  (self.__class__, methodName))
+        self._testMethodDoc = testMethod.__doc__
+        self._cleanups = []
+
+        # Map types to custom assertEqual functions that will compare
+        # instances of said type in more detail to generate a more useful
+        # error message.
+        self._type_equality_funcs = _TypeEqualityDict(self)
+        self.addTypeEqualityFunc(dict, 'assertDictEqual')
+        self.addTypeEqualityFunc(list, 'assertListEqual')
+        self.addTypeEqualityFunc(tuple, 'assertTupleEqual')
+        self.addTypeEqualityFunc(set, 'assertSetEqual')
+        self.addTypeEqualityFunc(frozenset, 'assertSetEqual')
+        self.addTypeEqualityFunc(unicode, 'assertMultiLineEqual')
+
+    def addTypeEqualityFunc(self, typeobj, function):
+        """Add a type specific assertEqual style function to compare a type.
+
+        This method is for use by TestCase subclasses that need to register
+        their own type equality functions to provide nicer error messages.
+
+        Args:
+            typeobj: The data type to call this function on when both values
+                    are of the same type in assertEqual().
+            function: The callable taking two arguments and an optional
+                    msg= argument that raises self.failureException with a
+                    useful error message when the two arguments are not equal.
+        """
+        self._type_equality_funcs[typeobj] = function
+
+    def addCleanup(self, function, *args, **kwargs):
+        """Add a function, with arguments, to be called when the test is
+        completed. Functions added are called on a LIFO basis and are
+        called after tearDown on test failure or success.
+
+        Cleanup items are called even if setUp fails (unlike tearDown)."""
+        self._cleanups.append((function, args, kwargs))
+
+    def setUp(self):
+        "Hook method for setting up the test fixture before exercising it."
+    
+    @classmethod
+    def setUpClass(cls):
+        "Hook method for setting up class fixture before running tests in the class."
+
+    @classmethod
+    def tearDownClass(cls):
+        "Hook method for deconstructing the class fixture after running all tests in the class."
+
+    def tearDown(self):
+        "Hook method for deconstructing the test fixture after testing it."
+
+    def countTestCases(self):
+        return 1
+
+    def defaultTestResult(self):
+        return result.TestResult()
+
+    def shortDescription(self):
+        """Returns a one-line description of the test, or None if no
+        description has been provided.
+
+        The default implementation of this method returns the first line of
+        the specified test method's docstring.
+        """
+        doc = self._testMethodDoc
+        return doc and doc.split("\n")[0].strip() or None
+
+
+    def id(self):
+        return "%s.%s" % (strclass(self.__class__), self._testMethodName)
+
+    def __eq__(self, other):
+        if type(self) is not type(other):
+            return NotImplemented
+
+        return self._testMethodName == other._testMethodName
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash((type(self), self._testMethodName))
+
+    def __str__(self):
+        return "%s (%s)" % (self._testMethodName, strclass(self.__class__))
+
+    def __repr__(self):
+        return "<%s testMethod=%s>" % \
+               (strclass(self.__class__), self._testMethodName)
+    
+    def _addSkip(self, result, reason):
+        addSkip = getattr(result, 'addSkip', None)
+        if addSkip is not None:
+            addSkip(self, reason)
+        else:
+            warnings.warn("Use of a TestResult without an addSkip method is deprecated", 
+                          DeprecationWarning, 2)
+            result.addSuccess(self)
+
+    def run(self, result=None):
+        orig_result = result
+        if result is None:
+            result = self.defaultTestResult()
+            startTestRun = getattr(result, 'startTestRun', None)
+            if startTestRun is not None:
+                startTestRun()
+
+        self._resultForDoCleanups = result
+        result.startTest(self)
+        
+        testMethod = getattr(self, self._testMethodName)
+        
+        if (getattr(self.__class__, "__unittest_skip__", False) or 
+            getattr(testMethod, "__unittest_skip__", False)):
+            # If the class or method was skipped.
+            try:
+                skip_why = (getattr(self.__class__, '__unittest_skip_why__', '')
+                            or getattr(testMethod, '__unittest_skip_why__', ''))
+                self._addSkip(result, skip_why)
+            finally:
+                result.stopTest(self)
+            return
+        try:
+            success = False
+            try:
+                self.setUp()
+            except SkipTest, e:
+                self._addSkip(result, str(e))
+            except Exception:
+                result.addError(self, sys.exc_info())
+            else:
+                try:
+                    testMethod()
+                except self.failureException:
+                    result.addFailure(self, sys.exc_info())
+                except _ExpectedFailure, e:
+                    addExpectedFailure = getattr(result, 'addExpectedFailure', None)
+                    if addExpectedFailure is not None:
+                        addExpectedFailure(self, e.exc_info)
+                    else: 
+                        warnings.warn("Use of a TestResult without an addExpectedFailure method is deprecated", 
+                                      DeprecationWarning)
+                        result.addSuccess(self)
+                except _UnexpectedSuccess:
+                    addUnexpectedSuccess = getattr(result, 'addUnexpectedSuccess', None)
+                    if addUnexpectedSuccess is not None:
+                        addUnexpectedSuccess(self)
+                    else:
+                        warnings.warn("Use of a TestResult without an addUnexpectedSuccess method is deprecated", 
+                                      DeprecationWarning)
+                        result.addFailure(self, sys.exc_info())
+                except SkipTest, e:
+                    self._addSkip(result, str(e))
+                except Exception:
+                    result.addError(self, sys.exc_info())
+                else:
+                    success = True
+
+                try:
+                    self.tearDown()
+                except Exception:
+                    result.addError(self, sys.exc_info())
+                    success = False
+
+            cleanUpSuccess = self.doCleanups()
+            success = success and cleanUpSuccess
+            if success:
+                result.addSuccess(self)
+        finally:
+            result.stopTest(self)
+            if orig_result is None:
+                stopTestRun = getattr(result, 'stopTestRun', None)
+                if stopTestRun is not None:
+                    stopTestRun()
+
+    def doCleanups(self):
+        """Execute all cleanup functions. Normally called for you after
+        tearDown."""
+        result = self._resultForDoCleanups
+        ok = True
+        while self._cleanups:
+            function, args, kwargs = self._cleanups.pop(-1)
+            try:
+                function(*args, **kwargs)
+            except Exception:
+                ok = False
+                result.addError(self, sys.exc_info())
+        return ok
+
+    def __call__(self, *args, **kwds):
+        return self.run(*args, **kwds)
+
+    def debug(self):
+        """Run the test without collecting errors in a TestResult"""
+        self.setUp()
+        getattr(self, self._testMethodName)()
+        self.tearDown()
+        while self._cleanups:
+            function, args, kwargs = self._cleanups.pop(-1)
+            function(*args, **kwargs)
+
+    def skipTest(self, reason):
+        """Skip this test."""
+        raise SkipTest(reason)
+
+    def fail(self, msg=None):
+        """Fail immediately, with the given message."""
+        raise self.failureException(msg)
+
+    def assertFalse(self, expr, msg=None):
+        "Fail the test if the expression is true."
+        if expr:
+            msg = self._formatMessage(msg, "%s is not False" % safe_repr(expr))
+            raise self.failureException(msg)
+
+    def assertTrue(self, expr, msg=None):
+        """Fail the test unless the expression is true."""
+        if not expr:
+            msg = self._formatMessage(msg, "%s is not True" % safe_repr(expr))
+            raise self.failureException(msg)
+
+    def _formatMessage(self, msg, standardMsg):
+        """Honour the longMessage attribute when generating failure messages.
+        If longMessage is False this means:
+        * Use only an explicit message if it is provided
+        * Otherwise use the standard message for the assert
+
+        If longMessage is True:
+        * Use the standard message
+        * If an explicit message is provided, plus ' : ' and the explicit message
+        """
+        if not self.longMessage:
+            return msg or standardMsg
+        if msg is None:
+            return standardMsg
+        try:
+            return '%s : %s' % (standardMsg, msg)
+        except UnicodeDecodeError:
+            return '%s : %s' % (safe_str(standardMsg), safe_str(msg))
+
+
+    def assertRaises(self, excClass, callableObj=None, *args, **kwargs):
+        """Fail unless an exception of class excClass is thrown
+           by callableObj when invoked with arguments args and keyword
+           arguments kwargs. If a different type of exception is
+           thrown, it will not be caught, and the test case will be
+           deemed to have suffered an error, exactly as for an
+           unexpected exception.
+
+           If called with callableObj omitted or None, will return a
+           context object used like this::
+
+                with self.assertRaises(SomeException):
+                    do_something()
+
+           The context manager keeps a reference to the exception as
+           the 'exception' attribute. This allows you to inspect the
+           exception after the assertion::
+
+               with self.assertRaises(SomeException) as cm:
+                   do_something()
+               the_exception = cm.exception
+               self.assertEqual(the_exception.error_code, 3)
+        """
+        if callableObj is None:
+            return _AssertRaisesContext(excClass, self)
+        try:
+            callableObj(*args, **kwargs)
+        except excClass:
+            return
+        
+        if hasattr(excClass,'__name__'):
+            excName = excClass.__name__
+        else:
+            excName = str(excClass)
+        raise self.failureException, "%s not raised" % excName
+
+    def _getAssertEqualityFunc(self, first, second):
+        """Get a detailed comparison function for the types of the two args.
+
+        Returns: A callable accepting (first, second, msg=None) that will
+        raise a failure exception if first != second with a useful human
+        readable error message for those types.
+        """
+        #
+        # NOTE(gregory.p.smith): I considered isinstance(first, type(second))
+        # and vice versa.  I opted for the conservative approach in case
+        # subclasses are not intended to be compared in detail to their super
+        # class instances using a type equality func.  This means testing
+        # subtypes won't automagically use the detailed comparison.  Callers
+        # should use their type specific assertSpamEqual method to compare
+        # subclasses if the detailed comparison is desired and appropriate.
+        # See the discussion in http://bugs.python.org/issue2578.
+        #
+        if type(first) is type(second):
+            asserter = self._type_equality_funcs.get(type(first))
+            if asserter is not None:
+                return asserter
+
+        return self._baseAssertEqual
+
+    def _baseAssertEqual(self, first, second, msg=None):
+        """The default assertEqual implementation, not type specific."""
+        if not first == second:
+            standardMsg = '%s != %s' % (safe_repr(first), safe_repr(second))
+            msg = self._formatMessage(msg, standardMsg)
+            raise self.failureException(msg)
+
+    def assertEqual(self, first, second, msg=None):
+        """Fail if the two objects are unequal as determined by the '=='
+           operator.
+        """
+        assertion_func = self._getAssertEqualityFunc(first, second)
+        assertion_func(first, second, msg=msg)
+
+    def assertNotEqual(self, first, second, msg=None):
+        """Fail if the two objects are equal as determined by the '=='
+           operator.
+        """
+        if not first != second:
+            msg = self._formatMessage(msg, '%s == %s' % (safe_repr(first), 
+                                                           safe_repr(second)))
+            raise self.failureException(msg)
+
+    def assertAlmostEqual(self, first, second, places=None, msg=None, delta=None):
+        """Fail if the two objects are unequal as determined by their
+           difference rounded to the given number of decimal places
+           (default 7) and comparing to zero, or by comparing that the
+           between the two objects is more than the given delta.
+
+           Note that decimal places (from zero) are usually not the same
+           as significant digits (measured from the most signficant digit).
+
+           If the two objects compare equal then they will automatically
+           compare almost equal.
+        """
+        if first == second:
+            # shortcut
+            return
+        if delta is not None and places is not None:
+            raise TypeError("specify delta or places not both")
+        
+        if delta is not None:
+            if abs(first - second) <= delta:
+                return
+        
+            standardMsg = '%s != %s within %s delta' % (safe_repr(first), 
+                                                        safe_repr(second), 
+                                                        safe_repr(delta))
+        else:
+            if places is None:
+                places = 7
+                
+            if round(abs(second-first), places) == 0:
+                return
+        
+            standardMsg = '%s != %s within %r places' % (safe_repr(first), 
+                                                          safe_repr(second), 
+                                                          places)
+        msg = self._formatMessage(msg, standardMsg)
+        raise self.failureException(msg)
+
+    def assertNotAlmostEqual(self, first, second, places=None, msg=None, delta=None):
+        """Fail if the two objects are equal as determined by their
+           difference rounded to the given number of decimal places
+           (default 7) and comparing to zero, or by comparing that the
+           between the two objects is less than the given delta.
+
+           Note that decimal places (from zero) are usually not the same
+           as significant digits (measured from the most signficant digit).
+
+           Objects that are equal automatically fail.
+        """
+        if delta is not None and places is not None:
+            raise TypeError("specify delta or places not both")
+        if delta is not None:
+            if not (first == second) and abs(first - second) > delta:
+                return
+            standardMsg = '%s == %s within %s delta' % (safe_repr(first), 
+                                                        safe_repr(second),
+                                                        safe_repr(delta))
+        else:
+            if places is None:
+                places = 7
+            if not (first == second) and round(abs(second-first), places) != 0:
+                return
+            standardMsg = '%s == %s within %r places' % (safe_repr(first), 
+                                                         safe_repr(second),
+                                                         places)
+
+        msg = self._formatMessage(msg, standardMsg)
+        raise self.failureException(msg)
+
+    # Synonyms for assertion methods
+
+    # The plurals are undocumented.  Keep them that way to discourage use.
+    # Do not add more.  Do not remove.
+    # Going through a deprecation cycle on these would annoy many people.
+    assertEquals = assertEqual
+    assertNotEquals = assertNotEqual
+    assertAlmostEquals = assertAlmostEqual
+    assertNotAlmostEquals = assertNotAlmostEqual
+    assert_ = assertTrue
+
+    # These fail* assertion method names are pending deprecation and will
+    # be a DeprecationWarning in 3.2; http://bugs.python.org/issue2578
+    def _deprecate(original_func):
+        def deprecated_func(*args, **kwargs):
+            warnings.warn(
+                ('Please use %s instead.' % original_func.__name__),
+                PendingDeprecationWarning, 2)
+            return original_func(*args, **kwargs)
+        return deprecated_func
+
+    failUnlessEqual = _deprecate(assertEqual)
+    failIfEqual = _deprecate(assertNotEqual)
+    failUnlessAlmostEqual = _deprecate(assertAlmostEqual)
+    failIfAlmostEqual = _deprecate(assertNotAlmostEqual)
+    failUnless = _deprecate(assertTrue)
+    failUnlessRaises = _deprecate(assertRaises)
+    failIf = _deprecate(assertFalse)
+
+    def assertSequenceEqual(self, seq1, seq2,
+                            msg=None, seq_type=None, max_diff=80*8):
+        """An equality assertion for ordered sequences (like lists and tuples).
+
+        For the purposes of this function, a valid ordered sequence type is one
+        which can be indexed, has a length, and has an equality operator.
+
+        Args:
+            seq1: The first sequence to compare.
+            seq2: The second sequence to compare.
+            seq_type: The expected datatype of the sequences, or None if no
+                    datatype should be enforced.
+            msg: Optional message to use on failure instead of a list of
+                    differences.
+            max_diff: Maximum size off the diff, larger diffs are not shown
+        """
+        if seq_type is not None:
+            seq_type_name = seq_type.__name__
+            if not isinstance(seq1, seq_type):
+                raise self.failureException('First sequence is not a %s: %s'
+                                            % (seq_type_name, safe_repr(seq1)))
+            if not isinstance(seq2, seq_type):
+                raise self.failureException('Second sequence is not a %s: %s'
+                                            % (seq_type_name, safe_repr(seq2)))
+        else:
+            seq_type_name = "sequence"
+
+        differing = None
+        try:
+            len1 = len(seq1)
+        except (TypeError, NotImplementedError):
+            differing = 'First %s has no length.    Non-sequence?' % (
+                    seq_type_name)
+
+        if differing is None:
+            try:
+                len2 = len(seq2)
+            except (TypeError, NotImplementedError):
+                differing = 'Second %s has no length.    Non-sequence?' % (
+                        seq_type_name)
+
+        if differing is None:
+            if seq1 == seq2:
+                return
+
+            seq1_repr = repr(seq1)
+            seq2_repr = repr(seq2)
+            if len(seq1_repr) > 30:
+                seq1_repr = seq1_repr[:30] + '...'
+            if len(seq2_repr) > 30:
+                seq2_repr = seq2_repr[:30] + '...'
+            elements = (seq_type_name.capitalize(), seq1_repr, seq2_repr)
+            differing = '%ss differ: %s != %s\n' % elements
+
+            for i in xrange(min(len1, len2)):
+                try:
+                    item1 = seq1[i]
+                except (TypeError, IndexError, NotImplementedError):
+                    differing += ('\nUnable to index element %d of first %s\n' %
+                                 (i, seq_type_name))
+                    break
+
+                try:
+                    item2 = seq2[i]
+                except (TypeError, IndexError, NotImplementedError):
+                    differing += ('\nUnable to index element %d of second %s\n' %
+                                 (i, seq_type_name))
+                    break
+
+                if item1 != item2:
+                    differing += ('\nFirst differing element %d:\n%s\n%s\n' %
+                                 (i, item1, item2))
+                    break
+            else:
+                if (len1 == len2 and seq_type is None and
+                    type(seq1) != type(seq2)):
+                    # The sequences are the same, but have differing types.
+                    return
+
+            if len1 > len2:
+                differing += ('\nFirst %s contains %d additional '
+                             'elements.\n' % (seq_type_name, len1 - len2))
+                try:
+                    differing += ('First extra element %d:\n%s\n' %
+                                  (len2, seq1[len2]))
+                except (TypeError, IndexError, NotImplementedError):
+                    differing += ('Unable to index element %d '
+                                  'of first %s\n' % (len2, seq_type_name))
+            elif len1 < len2:
+                differing += ('\nSecond %s contains %d additional '
+                             'elements.\n' % (seq_type_name, len2 - len1))
+                try:
+                    differing += ('First extra element %d:\n%s\n' %
+                                  (len1, seq2[len1]))
+                except (TypeError, IndexError, NotImplementedError):
+                    differing += ('Unable to index element %d '
+                                  'of second %s\n' % (len1, seq_type_name))
+        standardMsg = differing
+        diffMsg = '\n' + '\n'.join(
+            difflib.ndiff(pprint.pformat(seq1).splitlines(),
+                          pprint.pformat(seq2).splitlines()))
+
+        standardMsg = self._truncateMessage(standardMsg, diffMsg)
+        msg = self._formatMessage(msg, standardMsg)
+        self.fail(msg)
+
+    def _truncateMessage(self, message, diff):
+        max_diff = self.maxDiff
+        if max_diff is None or len(diff) <= max_diff:
+            return message + diff
+        return message + (DIFF_OMITTED % len(diff))
+
+    def assertListEqual(self, list1, list2, msg=None):
+        """A list-specific equality assertion.
+
+        Args:
+            list1: The first list to compare.
+            list2: The second list to compare.
+            msg: Optional message to use on failure instead of a list of
+                    differences.
+
+        """
+        self.assertSequenceEqual(list1, list2, msg, seq_type=list)
+
+    def assertTupleEqual(self, tuple1, tuple2, msg=None):
+        """A tuple-specific equality assertion.
+
+        Args:
+            tuple1: The first tuple to compare.
+            tuple2: The second tuple to compare.
+            msg: Optional message to use on failure instead of a list of
+                    differences.
+        """
+        self.assertSequenceEqual(tuple1, tuple2, msg, seq_type=tuple)
+
+    def assertSetEqual(self, set1, set2, msg=None):
+        """A set-specific equality assertion.
+
+        Args:
+            set1: The first set to compare.
+            set2: The second set to compare.
+            msg: Optional message to use on failure instead of a list of
+                    differences.
+
+        assertSetEqual uses ducktyping to support
+        different types of sets, and is optimized for sets specifically
+        (parameters must support a difference method).
+        """
+        try:
+            difference1 = set1.difference(set2)
+        except TypeError, e:
+            self.fail('invalid type when attempting set difference: %s' % e)
+        except AttributeError, e:
+            self.fail('first argument does not support set difference: %s' % e)
+
+        try:
+            difference2 = set2.difference(set1)
+        except TypeError, e:
+            self.fail('invalid type when attempting set difference: %s' % e)
+        except AttributeError, e:
+            self.fail('second argument does not support set difference: %s' % e)
+
+        if not (difference1 or difference2):
+            return
+
+        lines = []
+        if difference1:
+            lines.append('Items in the first set but not the second:')
+            for item in difference1:
+                lines.append(repr(item))
+        if difference2:
+            lines.append('Items in the second set but not the first:')
+            for item in difference2:
+                lines.append(repr(item))
+
+        standardMsg = '\n'.join(lines)
+        self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertIn(self, member, container, msg=None):
+        """Just like self.assertTrue(a in b), but with a nicer default message."""
+        if member not in container:
+            standardMsg = '%s not found in %s' % (safe_repr(member), 
+                                                   safe_repr(container))
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertNotIn(self, member, container, msg=None):
+        """Just like self.assertTrue(a not in b), but with a nicer default message."""
+        if member in container:
+            standardMsg = '%s unexpectedly found in %s' % (safe_repr(member), 
+                                                            safe_repr(container))
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertIs(self, expr1, expr2, msg=None):
+        """Just like self.assertTrue(a is b), but with a nicer default message."""
+        if expr1 is not expr2:
+            standardMsg = '%s is not %s' % (safe_repr(expr1), safe_repr(expr2))
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertIsNot(self, expr1, expr2, msg=None):
+        """Just like self.assertTrue(a is not b), but with a nicer default message."""
+        if expr1 is expr2:
+            standardMsg = 'unexpectedly identical: %s' % (safe_repr(expr1),)
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertDictEqual(self, d1, d2, msg=None):
+        self.assert_(isinstance(d1, dict), 'First argument is not a dictionary')
+        self.assert_(isinstance(d2, dict), 'Second argument is not a dictionary')
+
+        if d1 != d2:
+            standardMsg = '%s != %s' % (safe_repr(d1, True), safe_repr(d2, True))
+            diff = ('\n' + '\n'.join(difflib.ndiff(
+                           pprint.pformat(d1).splitlines(),
+                           pprint.pformat(d2).splitlines())))
+            standardMsg = self._truncateMessage(standardMsg, diff)
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertDictContainsSubset(self, expected, actual, msg=None):
+        """Checks whether actual is a superset of expected."""
+        missing = []
+        mismatched = []
+        for key, value in expected.iteritems():
+            if key not in actual:
+                missing.append(key)
+            elif value != actual[key]:
+                mismatched.append('%s, expected: %s, actual: %s' %
+                                  (safe_repr(key), safe_repr(value), 
+                                   safe_repr(actual[key])))
+
+        if not (missing or mismatched):
+            return
+
+        standardMsg = ''
+        if missing:
+            standardMsg = 'Missing: %s' % ','.join(safe_repr(m) for m in 
+                                                    missing)
+        if mismatched:
+            if standardMsg:
+                standardMsg += '; '
+            standardMsg += 'Mismatched values: %s' % ','.join(mismatched)
+
+        self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertItemsEqual(self, expected_seq, actual_seq, msg=None):
+        """An unordered sequence specific comparison. It asserts that
+        expected_seq and actual_seq contain the same elements. It is
+        the equivalent of::
+        
+            self.assertEqual(sorted(expected_seq), sorted(actual_seq))
+
+        Raises with an error message listing which elements of expected_seq
+        are missing from actual_seq and vice versa if any.
+        
+        Asserts that each element has the same count in both sequences.
+        Example:
+            - [0, 1, 1] and [1, 0, 1] compare equal.
+            - [0, 0, 1] and [0, 1] compare unequal.
+        """
+        try:
+            expected = sorted(expected_seq)
+            actual = sorted(actual_seq)
+        except TypeError:
+            # Unsortable items (example: set(), complex(), ...)
+            expected = list(expected_seq)
+            actual = list(actual_seq)
+            missing, unexpected = unorderable_list_difference(
+                expected, actual, ignore_duplicate=False
+            )
+        else:
+            return self.assertSequenceEqual(expected, actual, msg=msg)
+
+        errors = []
+        if missing:
+            errors.append('Expected, but missing:\n    %s' % 
+                           safe_repr(missing))
+        if unexpected:
+            errors.append('Unexpected, but present:\n    %s' % 
+                           safe_repr(unexpected))
+        if errors:
+            standardMsg = '\n'.join(errors)
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertMultiLineEqual(self, first, second, msg=None):
+        """Assert that two multi-line strings are equal."""
+        self.assert_(isinstance(first, basestring), (
+                'First argument is not a string'))
+        self.assert_(isinstance(second, basestring), (
+                'Second argument is not a string'))
+
+        if first != second:
+            standardMsg = '%s != %s' % (safe_repr(first, True), safe_repr(second, True))
+            diff = '\n' + ''.join(difflib.ndiff(first.splitlines(True),
+                                                       second.splitlines(True)))
+            standardMsg = self._truncateMessage(standardMsg, diff)
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertLess(self, a, b, msg=None):
+        """Just like self.assertTrue(a < b), but with a nicer default message."""
+        if not a < b:
+            standardMsg = '%s not less than %s' % (safe_repr(a), safe_repr(b))
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertLessEqual(self, a, b, msg=None):
+        """Just like self.assertTrue(a <= b), but with a nicer default message."""
+        if not a <= b:
+            standardMsg = '%s not less than or equal to %s' % (safe_repr(a), safe_repr(b))
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertGreater(self, a, b, msg=None):
+        """Just like self.assertTrue(a > b), but with a nicer default message."""
+        if not a > b:
+            standardMsg = '%s not greater than %s' % (safe_repr(a), safe_repr(b))
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertGreaterEqual(self, a, b, msg=None):
+        """Just like self.assertTrue(a >= b), but with a nicer default message."""
+        if not a >= b:
+            standardMsg = '%s not greater than or equal to %s' % (safe_repr(a), safe_repr(b))
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertIsNone(self, obj, msg=None):
+        """Same as self.assertTrue(obj is None), with a nicer default message."""
+        if obj is not None:
+            standardMsg = '%s is not None' % (safe_repr(obj),)
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertIsNotNone(self, obj, msg=None):
+        """Included for symmetry with assertIsNone."""
+        if obj is None:
+            standardMsg = 'unexpectedly None'
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertIsInstance(self, obj, cls, msg=None):
+        """Same as self.assertTrue(isinstance(obj, cls)), with a nicer
+        default message."""
+        if not isinstance(obj, cls):
+            standardMsg = '%s is not an instance of %r' % (safe_repr(obj), cls)
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertNotIsInstance(self, obj, cls, msg=None):
+        """Included for symmetry with assertIsInstance."""
+        if isinstance(obj, cls):
+            standardMsg = '%s is an instance of %r' % (safe_repr(obj), cls)
+            self.fail(self._formatMessage(msg, standardMsg))
+
+    def assertRaisesRegexp(self, expected_exception, expected_regexp,
+                           callable_obj=None, *args, **kwargs):
+        """Asserts that the message in a raised exception matches a regexp.
+
+        Args:
+            expected_exception: Exception class expected to be raised.
+            expected_regexp: Regexp (re pattern object or string) expected
+                    to be found in error message.
+            callable_obj: Function to be called.
+            args: Extra args.
+            kwargs: Extra kwargs.
+        """
+        if callable_obj is None:
+            return _AssertRaisesContext(expected_exception, self, expected_regexp)
+        try:
+            callable_obj(*args, **kwargs)
+        except expected_exception, exc_value:
+            if isinstance(expected_regexp, basestring):
+                expected_regexp = re.compile(expected_regexp)
+            if not expected_regexp.search(str(exc_value)):
+                raise self.failureException('"%s" does not match "%s"' %
+                         (expected_regexp.pattern, str(exc_value)))
+        else:
+            if hasattr(expected_exception, '__name__'): 
+                excName = expected_exception.__name__
+            else: 
+                excName = str(expected_exception)
+            raise self.failureException, "%s not raised" % excName
+
+
+    def assertRegexpMatches(self, text, expected_regexp, msg=None):
+        """Fail the test unless the text matches the regular expression."""
+        if isinstance(expected_regexp, basestring):
+            expected_regexp = re.compile(expected_regexp)
+        if not expected_regexp.search(text):
+            msg = msg or "Regexp didn't match"
+            msg = '%s: %r not found in %r' % (msg, expected_regexp.pattern, text)
+            raise self.failureException(msg)
+
+    def assertNotRegexpMatches(self, text, unexpected_regexp, msg=None):
+        """Fail the test if the text matches the regular expression."""
+        if isinstance(unexpected_regexp, basestring):
+            unexpected_regexp = re.compile(unexpected_regexp)
+        match = unexpected_regexp.search(text)
+        if match:
+            msg = msg or "Regexp matched"
+            msg = '%s: %r matches %r in %r' % (msg,
+                                               text[match.start():match.end()],
+                                               unexpected_regexp.pattern,
+                                               text)
+            raise self.failureException(msg)
+
+class FunctionTestCase(TestCase):
+    """A test case that wraps a test function.
+
+    This is useful for slipping pre-existing test functions into the
+    unittest framework. Optionally, set-up and tidy-up functions can be
+    supplied. As with TestCase, the tidy-up ('tearDown') function will
+    always be called if the set-up ('setUp') function ran successfully.
+    """
+
+    def __init__(self, testFunc, setUp=None, tearDown=None, description=None):
+        super(FunctionTestCase, self).__init__()
+        self._setUpFunc = setUp
+        self._tearDownFunc = tearDown
+        self._testFunc = testFunc
+        self._description = description
+
+    def setUp(self):
+        if self._setUpFunc is not None:
+            self._setUpFunc()
+
+    def tearDown(self):
+        if self._tearDownFunc is not None:
+            self._tearDownFunc()
+
+    def runTest(self):
+        self._testFunc()
+
+    def id(self):
+        return self._testFunc.__name__
+
+    def __eq__(self, other):
+        if not isinstance(other, self.__class__):
+            return NotImplemented
+
+        return self._setUpFunc == other._setUpFunc and \
+               self._tearDownFunc == other._tearDownFunc and \
+               self._testFunc == other._testFunc and \
+               self._description == other._description
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash((type(self), self._setUpFunc, self._tearDownFunc,
+                     self._testFunc, self._description))
+
+    def __str__(self):
+        return "%s (%s)" % (strclass(self.__class__),
+                            self._testFunc.__name__)
+
+    def __repr__(self):
+        return "<%s testFunc=%s>" % (strclass(self.__class__),
+                                     self._testFunc)
+
+    def shortDescription(self):
+        if self._description is not None:
+            return self._description
+        doc = self._testFunc.__doc__
+        return doc and doc.split("\n")[0].strip() or None