Update web-platform-tests to revision be5419e845d39089ba6dc338c1bd0fa279108317

1 files changed, 0 insertions, 2302 deletions

diff --git a/tests/wpt/web-platform-tests/tools/pytest/_pytest/python.py b/tests/wpt/web-platform-tests/tools/pytest/_pytest/python.py
deleted file mode 100644
index 3580eae074f..00000000000
--- a/tests/wpt/web-platform-tests/tools/pytest/_pytest/python.py
+++ /dev/null
@@ -1,2302 +0,0 @@
-""" Python test discovery, setup and run of test functions. """
-import fnmatch
-import functools
-import inspect
-import re
-import types
-import sys
-
-import py
-import pytest
-from _pytest._code.code import TerminalRepr
-from _pytest.mark import MarkDecorator, MarkerError
-
-try:
-    import enum
-except ImportError:  # pragma: no cover
-    # Only available in Python 3.4+ or as a backport
-    enum = None
-
-import _pytest
-import _pytest._pluggy as pluggy
-
-cutdir2 = py.path.local(_pytest.__file__).dirpath()
-cutdir1 = py.path.local(pluggy.__file__.rstrip("oc"))
-
-
-NoneType = type(None)
-NOTSET = object()
-isfunction = inspect.isfunction
-isclass = inspect.isclass
-callable = py.builtin.callable
-# used to work around a python2 exception info leak
-exc_clear = getattr(sys, 'exc_clear', lambda: None)
-# The type of re.compile objects is not exposed in Python.
-REGEX_TYPE = type(re.compile(''))
-
-_PY3 = sys.version_info > (3, 0)
-_PY2 = not _PY3
-
-
-if hasattr(inspect, 'signature'):
-    def _format_args(func):
-        return str(inspect.signature(func))
-else:
-    def _format_args(func):
-        return inspect.formatargspec(*inspect.getargspec(func))
-
-if  sys.version_info[:2] == (2, 6):
-    def isclass(object):
-        """ Return true if the object is a class. Overrides inspect.isclass for
-        python 2.6 because it will return True for objects which always return
-        something on __getattr__ calls (see #1035).
-        Backport of https://hg.python.org/cpython/rev/35bf8f7a8edc
-        """
-        return isinstance(object, (type, types.ClassType))
-
-def _has_positional_arg(func):
-    return func.__code__.co_argcount
-
-
-def filter_traceback(entry):
-    # entry.path might sometimes return a str object when the entry
-    # points to dynamically generated code
-    # see https://bitbucket.org/pytest-dev/py/issues/71
-    raw_filename = entry.frame.code.raw.co_filename
-    is_generated = '<' in raw_filename and '>' in raw_filename
-    if is_generated:
-        return False
-    # entry.path might point to an inexisting file, in which case it will
-    # alsso return a str object. see #1133
-    p = py.path.local(entry.path)
-    return p != cutdir1 and not p.relto(cutdir2)
-
-
-def get_real_func(obj):
-    """ gets the real function object of the (possibly) wrapped object by
-    functools.wraps or functools.partial.
-    """
-    while hasattr(obj, "__wrapped__"):
-        obj = obj.__wrapped__
-    if isinstance(obj, functools.partial):
-        obj = obj.func
-    return obj
-
-def getfslineno(obj):
-    # xxx let decorators etc specify a sane ordering
-    obj = get_real_func(obj)
-    if hasattr(obj, 'place_as'):
-        obj = obj.place_as
-    fslineno = _pytest._code.getfslineno(obj)
-    assert isinstance(fslineno[1], int), obj
-    return fslineno
-
-def getimfunc(func):
-    try:
-        return func.__func__
-    except AttributeError:
-        try:
-            return func.im_func
-        except AttributeError:
-            return func
-
-def safe_getattr(object, name, default):
-    """ Like getattr but return default upon any Exception.
-
-    Attribute access can potentially fail for 'evil' Python objects.
-    See issue214
-    """
-    try:
-        return getattr(object, name, default)
-    except Exception:
-        return default
-
-
-class FixtureFunctionMarker:
-    def __init__(self, scope, params,
-                 autouse=False, yieldctx=False, ids=None):
-        self.scope = scope
-        self.params = params
-        self.autouse = autouse
-        self.yieldctx = yieldctx
-        self.ids = ids
-
-    def __call__(self, function):
-        if isclass(function):
-            raise ValueError(
-                    "class fixtures not supported (may be in the future)")
-        function._pytestfixturefunction = self
-        return function
-
-
-def fixture(scope="function", params=None, autouse=False, ids=None):
-    """ (return a) decorator to mark a fixture factory function.
-
-    This decorator can be used (with or or without parameters) to define
-    a fixture function.  The name of the fixture function can later be
-    referenced to cause its invocation ahead of running tests: test
-    modules or classes can use the pytest.mark.usefixtures(fixturename)
-    marker.  Test functions can directly use fixture names as input
-    arguments in which case the fixture instance returned from the fixture
-    function will be injected.
-
-    :arg scope: the scope for which this fixture is shared, one of
-                "function" (default), "class", "module", "session".
-
-    :arg params: an optional list of parameters which will cause multiple
-                invocations of the fixture function and all of the tests
-                using it.
-
-    :arg autouse: if True, the fixture func is activated for all tests that
-                can see it.  If False (the default) then an explicit
-                reference is needed to activate the fixture.
-
-    :arg ids: list of string ids each corresponding to the params
-       so that they are part of the test id. If no ids are provided
-       they will be generated automatically from the params.
-
-    """
-    if callable(scope) and params is None and autouse == False:
-        # direct decoration
-        return FixtureFunctionMarker(
-                "function", params, autouse)(scope)
-    if params is not None and not isinstance(params, (list, tuple)):
-        params = list(params)
-    return FixtureFunctionMarker(scope, params, autouse, ids=ids)
-
-def yield_fixture(scope="function", params=None, autouse=False, ids=None):
-    """ (return a) decorator to mark a yield-fixture factory function
-    (EXPERIMENTAL).
-
-    This takes the same arguments as :py:func:`pytest.fixture` but
-    expects a fixture function to use a ``yield`` instead of a ``return``
-    statement to provide a fixture.  See
-    http://pytest.org/en/latest/yieldfixture.html for more info.
-    """
-    if callable(scope) and params is None and autouse == False:
-        # direct decoration
-        return FixtureFunctionMarker(
-                "function", params, autouse, yieldctx=True)(scope)
-    else:
-        return FixtureFunctionMarker(scope, params, autouse,
-                                     yieldctx=True, ids=ids)
-
-defaultfuncargprefixmarker = fixture()
-
-def pyobj_property(name):
-    def get(self):
-        node = self.getparent(getattr(pytest, name))
-        if node is not None:
-            return node.obj
-    doc = "python %s object this node was collected from (can be None)." % (
-          name.lower(),)
-    return property(get, None, None, doc)
-
-
-def pytest_addoption(parser):
-    group = parser.getgroup("general")
-    group.addoption('--fixtures', '--funcargs',
-               action="store_true", dest="showfixtures", default=False,
-               help="show available fixtures, sorted by plugin appearance")
-    parser.addini("usefixtures", type="args", default=[],
-        help="list of default fixtures to be used with this project")
-    parser.addini("python_files", type="args",
-        default=['test_*.py', '*_test.py'],
-        help="glob-style file patterns for Python test module discovery")
-    parser.addini("python_classes", type="args", default=["Test",],
-        help="prefixes or glob names for Python test class discovery")
-    parser.addini("python_functions", type="args", default=["test",],
-        help="prefixes or glob names for Python test function and "
-             "method discovery")
-
-    group.addoption("--import-mode", default="prepend",
-        choices=["prepend", "append"], dest="importmode",
-        help="prepend/append to sys.path when importing test modules, "
-             "default is to prepend.")
-
-
-def pytest_cmdline_main(config):
-    if config.option.showfixtures:
-        showfixtures(config)
-        return 0
-
-
-def pytest_generate_tests(metafunc):
-    # those alternative spellings are common - raise a specific error to alert
-    # the user
-    alt_spellings = ['parameterize', 'parametrise', 'parameterise']
-    for attr in alt_spellings:
-        if hasattr(metafunc.function, attr):
-            msg = "{0} has '{1}', spelling should be 'parametrize'"
-            raise MarkerError(msg.format(metafunc.function.__name__, attr))
-    try:
-        markers = metafunc.function.parametrize
-    except AttributeError:
-        return
-    for marker in markers:
-        metafunc.parametrize(*marker.args, **marker.kwargs)
-
-def pytest_configure(config):
-    config.addinivalue_line("markers",
-        "parametrize(argnames, argvalues): call a test function multiple "
-        "times passing in different arguments in turn. argvalues generally "
-        "needs to be a list of values if argnames specifies only one name "
-        "or a list of tuples of values if argnames specifies multiple names. "
-        "Example: @parametrize('arg1', [1,2]) would lead to two calls of the "
-        "decorated test function, one with arg1=1 and another with arg1=2."
-        "see http://pytest.org/latest/parametrize.html for more info and "
-        "examples."
-    )
-    config.addinivalue_line("markers",
-        "usefixtures(fixturename1, fixturename2, ...): mark tests as needing "
-        "all of the specified fixtures. see http://pytest.org/latest/fixture.html#usefixtures "
-    )
-
-def pytest_sessionstart(session):
-    session._fixturemanager = FixtureManager(session)
-
-@pytest.hookimpl(trylast=True)
-def pytest_namespace():
-    raises.Exception = pytest.fail.Exception
-    return {
-        'fixture': fixture,
-        'yield_fixture': yield_fixture,
-        'raises' : raises,
-        'collect': {
-        'Module': Module, 'Class': Class, 'Instance': Instance,
-        'Function': Function, 'Generator': Generator,
-        '_fillfuncargs': fillfixtures}
-    }
-
-@fixture(scope="session")
-def pytestconfig(request):
-    """ the pytest config object with access to command line opts."""
-    return request.config
-
-
-@pytest.hookimpl(trylast=True)
-def pytest_pyfunc_call(pyfuncitem):
-    testfunction = pyfuncitem.obj
-    if pyfuncitem._isyieldedfunction():
-        testfunction(*pyfuncitem._args)
-    else:
-        funcargs = pyfuncitem.funcargs
-        testargs = {}
-        for arg in pyfuncitem._fixtureinfo.argnames:
-            testargs[arg] = funcargs[arg]
-        testfunction(**testargs)
-    return True
-
-def pytest_collect_file(path, parent):
-    ext = path.ext
-    if ext == ".py":
-        if not parent.session.isinitpath(path):
-            for pat in parent.config.getini('python_files'):
-                if path.fnmatch(pat):
-                    break
-            else:
-               return
-        ihook = parent.session.gethookproxy(path)
-        return ihook.pytest_pycollect_makemodule(path=path, parent=parent)
-
-def pytest_pycollect_makemodule(path, parent):
-    return Module(path, parent)
-
-@pytest.hookimpl(hookwrapper=True)
-def pytest_pycollect_makeitem(collector, name, obj):
-    outcome = yield
-    res = outcome.get_result()
-    if res is not None:
-        raise StopIteration
-    # nothing was collected elsewhere, let's do it here
-    if isclass(obj):
-        if collector.istestclass(obj, name):
-            Class = collector._getcustomclass("Class")
-            outcome.force_result(Class(name, parent=collector))
-    elif collector.istestfunction(obj, name):
-        # mock seems to store unbound methods (issue473), normalize it
-        obj = getattr(obj, "__func__", obj)
-        # We need to try and unwrap the function if it's a functools.partial
-        # or a funtools.wrapped.
-        # We musn't if it's been wrapped with mock.patch (python 2 only)
-        if not (isfunction(obj) or isfunction(get_real_func(obj))):
-            collector.warn(code="C2", message=
-                "cannot collect %r because it is not a function."
-                % name, )
-        elif getattr(obj, "__test__", True):
-            if is_generator(obj):
-                res = Generator(name, parent=collector)
-            else:
-                res = list(collector._genfunctions(name, obj))
-            outcome.force_result(res)
-
-def is_generator(func):
-    try:
-        return _pytest._code.getrawcode(func).co_flags & 32 # generator function
-    except AttributeError: # builtin functions have no bytecode
-        # assume them to not be generators
-        return False
-
-class PyobjContext(object):
-    module = pyobj_property("Module")
-    cls = pyobj_property("Class")
-    instance = pyobj_property("Instance")
-
-class PyobjMixin(PyobjContext):
-    def obj():
-        def fget(self):
-            try:
-                return self._obj
-            except AttributeError:
-                self._obj = obj = self._getobj()
-                return obj
-        def fset(self, value):
-            self._obj = value
-        return property(fget, fset, None, "underlying python object")
-    obj = obj()
-
-    def _getobj(self):
-        return getattr(self.parent.obj, self.name)
-
-    def getmodpath(self, stopatmodule=True, includemodule=False):
-        """ return python path relative to the containing module. """
-        chain = self.listchain()
-        chain.reverse()
-        parts = []
-        for node in chain:
-            if isinstance(node, Instance):
-                continue
-            name = node.name
-            if isinstance(node, Module):
-                assert name.endswith(".py")
-                name = name[:-3]
-                if stopatmodule:
-                    if includemodule:
-                        parts.append(name)
-                    break
-            parts.append(name)
-        parts.reverse()
-        s = ".".join(parts)
-        return s.replace(".[", "[")
-
-    def _getfslineno(self):
-        return getfslineno(self.obj)
-
-    def reportinfo(self):
-        # XXX caching?
-        obj = self.obj
-        compat_co_firstlineno = getattr(obj, 'compat_co_firstlineno', None)
-        if isinstance(compat_co_firstlineno, int):
-            # nose compatibility
-            fspath = sys.modules[obj.__module__].__file__
-            if fspath.endswith(".pyc"):
-                fspath = fspath[:-1]
-            lineno = compat_co_firstlineno
-        else:
-            fspath, lineno = getfslineno(obj)
-        modpath = self.getmodpath()
-        assert isinstance(lineno, int)
-        return fspath, lineno, modpath
-
-class PyCollector(PyobjMixin, pytest.Collector):
-
-    def funcnamefilter(self, name):
-        return self._matches_prefix_or_glob_option('python_functions', name)
-
-    def isnosetest(self, obj):
-        """ Look for the __test__ attribute, which is applied by the
-        @nose.tools.istest decorator
-        """
-        # We explicitly check for "is True" here to not mistakenly treat
-        # classes with a custom __getattr__ returning something truthy (like a
-        # function) as test classes.
-        return safe_getattr(obj, '__test__', False) is True
-
-    def classnamefilter(self, name):
-        return self._matches_prefix_or_glob_option('python_classes', name)
-
-    def istestfunction(self, obj, name):
-        return (
-            (self.funcnamefilter(name) or self.isnosetest(obj)) and
-            safe_getattr(obj, "__call__", False) and getfixturemarker(obj) is None
-        )
-
-    def istestclass(self, obj, name):
-        return self.classnamefilter(name) or self.isnosetest(obj)
-
-    def _matches_prefix_or_glob_option(self, option_name, name):
-        """
-        checks if the given name matches the prefix or glob-pattern defined
-        in ini configuration.
-        """
-        for option in self.config.getini(option_name):
-            if name.startswith(option):
-                return True
-            # check that name looks like a glob-string before calling fnmatch
-            # because this is called for every name in each collected module,
-            # and fnmatch is somewhat expensive to call
-            elif ('*' in option or '?' in option or '[' in option) and \
-                    fnmatch.fnmatch(name, option):
-                return True
-        return False
-
-    def collect(self):
-        if not getattr(self.obj, "__test__", True):
-            return []
-
-        # NB. we avoid random getattrs and peek in the __dict__ instead
-        # (XXX originally introduced from a PyPy need, still true?)
-        dicts = [getattr(self.obj, '__dict__', {})]
-        for basecls in inspect.getmro(self.obj.__class__):
-            dicts.append(basecls.__dict__)
-        seen = {}
-        l = []
-        for dic in dicts:
-            for name, obj in list(dic.items()):
-                if name in seen:
-                    continue
-                seen[name] = True
-                res = self.makeitem(name, obj)
-                if res is None:
-                    continue
-                if not isinstance(res, list):
-                    res = [res]
-                l.extend(res)
-        l.sort(key=lambda item: item.reportinfo()[:2])
-        return l
-
-    def makeitem(self, name, obj):
-        #assert self.ihook.fspath == self.fspath, self
-        return self.ihook.pytest_pycollect_makeitem(
-            collector=self, name=name, obj=obj)
-
-    def _genfunctions(self, name, funcobj):
-        module = self.getparent(Module).obj
-        clscol = self.getparent(Class)
-        cls = clscol and clscol.obj or None
-        transfer_markers(funcobj, cls, module)
-        fm = self.session._fixturemanager
-        fixtureinfo = fm.getfixtureinfo(self, funcobj, cls)
-        metafunc = Metafunc(funcobj, fixtureinfo, self.config,
-                            cls=cls, module=module)
-        methods = []
-        if hasattr(module, "pytest_generate_tests"):
-            methods.append(module.pytest_generate_tests)
-        if hasattr(cls, "pytest_generate_tests"):
-            methods.append(cls().pytest_generate_tests)
-        if methods:
-            self.ihook.pytest_generate_tests.call_extra(methods,
-                                                        dict(metafunc=metafunc))
-        else:
-            self.ihook.pytest_generate_tests(metafunc=metafunc)
-
-        Function = self._getcustomclass("Function")
-        if not metafunc._calls:
-            yield Function(name, parent=self, fixtureinfo=fixtureinfo)
-        else:
-            # add funcargs() as fixturedefs to fixtureinfo.arg2fixturedefs
-            add_funcarg_pseudo_fixture_def(self, metafunc, fm)
-
-            for callspec in metafunc._calls:
-                subname = "%s[%s]" %(name, callspec.id)
-                yield Function(name=subname, parent=self,
-                               callspec=callspec, callobj=funcobj,
-                               fixtureinfo=fixtureinfo,
-                               keywords={callspec.id:True})
-
-def add_funcarg_pseudo_fixture_def(collector, metafunc, fixturemanager):
-    # this function will transform all collected calls to a functions
-    # if they use direct funcargs (i.e. direct parametrization)
-    # because we want later test execution to be able to rely on
-    # an existing FixtureDef structure for all arguments.
-    # XXX we can probably avoid this algorithm  if we modify CallSpec2
-    # to directly care for creating the fixturedefs within its methods.
-    if not metafunc._calls[0].funcargs:
-        return # this function call does not have direct parametrization
-    # collect funcargs of all callspecs into a list of values
-    arg2params = {}
-    arg2scope = {}
-    for callspec in metafunc._calls:
-        for argname, argvalue in callspec.funcargs.items():
-            assert argname not in callspec.params
-            callspec.params[argname] = argvalue
-            arg2params_list = arg2params.setdefault(argname, [])
-            callspec.indices[argname] = len(arg2params_list)
-            arg2params_list.append(argvalue)
-            if argname not in arg2scope:
-                scopenum = callspec._arg2scopenum.get(argname,
-                                                      scopenum_function)
-                arg2scope[argname] = scopes[scopenum]
-        callspec.funcargs.clear()
-
-    # register artificial FixtureDef's so that later at test execution
-    # time we can rely on a proper FixtureDef to exist for fixture setup.
-    arg2fixturedefs = metafunc._arg2fixturedefs
-    for argname, valuelist in arg2params.items():
-        # if we have a scope that is higher than function we need
-        # to make sure we only ever create an according fixturedef on
-        # a per-scope basis. We thus store and cache the fixturedef on the
-        # node related to the scope.
-        scope = arg2scope[argname]
-        node = None
-        if scope != "function":
-            node = get_scope_node(collector, scope)
-            if node is None:
-                assert scope == "class" and isinstance(collector, Module)
-                # use module-level collector for class-scope (for now)
-                node = collector
-        if node and argname in node._name2pseudofixturedef:
-            arg2fixturedefs[argname] = [node._name2pseudofixturedef[argname]]
-        else:
-            fixturedef =  FixtureDef(fixturemanager, '', argname,
-                           get_direct_param_fixture_func,
-                           arg2scope[argname],
-                           valuelist, False, False)
-            arg2fixturedefs[argname] = [fixturedef]
-            if node is not None:
-                node._name2pseudofixturedef[argname] = fixturedef
-
-
-def get_direct_param_fixture_func(request):
-    return request.param
-
-class FuncFixtureInfo:
-    def __init__(self, argnames, names_closure, name2fixturedefs):
-        self.argnames = argnames
-        self.names_closure = names_closure
-        self.name2fixturedefs = name2fixturedefs
-
-
-def _marked(func, mark):
-    """ Returns True if :func: is already marked with :mark:, False otherwise.
-    This can happen if marker is applied to class and the test file is
-    invoked more than once.
-    """
-    try:
-        func_mark = getattr(func, mark.name)
-    except AttributeError:
-        return False
-    return mark.args == func_mark.args and mark.kwargs == func_mark.kwargs
-
-
-def transfer_markers(funcobj, cls, mod):
-    # XXX this should rather be code in the mark plugin or the mark
-    # plugin should merge with the python plugin.
-    for holder in (cls, mod):
-        try:
-            pytestmark = holder.pytestmark
-        except AttributeError:
-            continue
-        if isinstance(pytestmark, list):
-            for mark in pytestmark:
-                if not _marked(funcobj, mark):
-                    mark(funcobj)
-        else:
-            if not _marked(funcobj, pytestmark):
-                pytestmark(funcobj)
-
-class Module(pytest.File, PyCollector):
-    """ Collector for test classes and functions. """
-    def _getobj(self):
-        return self._memoizedcall('_obj', self._importtestmodule)
-
-    def collect(self):
-        self.session._fixturemanager.parsefactories(self)
-        return super(Module, self).collect()
-
-    def _importtestmodule(self):
-        # we assume we are only called once per module
-        importmode = self.config.getoption("--import-mode")
-        try:
-            mod = self.fspath.pyimport(ensuresyspath=importmode)
-        except SyntaxError:
-            raise self.CollectError(
-                _pytest._code.ExceptionInfo().getrepr(style="short"))
-        except self.fspath.ImportMismatchError:
-            e = sys.exc_info()[1]
-            raise self.CollectError(
-                "import file mismatch:\n"
-                "imported module %r has this __file__ attribute:\n"
-                "  %s\n"
-                "which is not the same as the test file we want to collect:\n"
-                "  %s\n"
-                "HINT: remove __pycache__ / .pyc files and/or use a "
-                "unique basename for your test file modules"
-                 % e.args
-            )
-        #print "imported test module", mod
-        self.config.pluginmanager.consider_module(mod)
-        return mod
-
-    def setup(self):
-        setup_module = xunitsetup(self.obj, "setUpModule")
-        if setup_module is None:
-            setup_module = xunitsetup(self.obj, "setup_module")
-        if setup_module is not None:
-            #XXX: nose compat hack, move to nose plugin
-            # if it takes a positional arg, its probably a pytest style one
-            # so we pass the current module object
-            if _has_positional_arg(setup_module):
-                setup_module(self.obj)
-            else:
-                setup_module()
-        fin = getattr(self.obj, 'tearDownModule', None)
-        if fin is None:
-            fin = getattr(self.obj, 'teardown_module', None)
-        if fin is not None:
-            #XXX: nose compat hack, move to nose plugin
-            # if it takes a positional arg, it's probably a pytest style one
-            # so we pass the current module object
-            if _has_positional_arg(fin):
-                finalizer = lambda: fin(self.obj)
-            else:
-                finalizer = fin
-            self.addfinalizer(finalizer)
-
-
-class Class(PyCollector):
-    """ Collector for test methods. """
-    def collect(self):
-        if hasinit(self.obj):
-            self.warn("C1", "cannot collect test class %r because it has a "
-                "__init__ constructor" % self.obj.__name__)
-            return []
-        return [self._getcustomclass("Instance")(name="()", parent=self)]
-
-    def setup(self):
-        setup_class = xunitsetup(self.obj, 'setup_class')
-        if setup_class is not None:
-            setup_class = getattr(setup_class, 'im_func', setup_class)
-            setup_class = getattr(setup_class, '__func__', setup_class)
-            setup_class(self.obj)
-
-        fin_class = getattr(self.obj, 'teardown_class', None)
-        if fin_class is not None:
-            fin_class = getattr(fin_class, 'im_func', fin_class)
-            fin_class = getattr(fin_class, '__func__', fin_class)
-            self.addfinalizer(lambda: fin_class(self.obj))
-
-class Instance(PyCollector):
-    def _getobj(self):
-        obj = self.parent.obj()
-        return obj
-
-    def collect(self):
-        self.session._fixturemanager.parsefactories(self)
-        return super(Instance, self).collect()
-
-    def newinstance(self):
-        self.obj = self._getobj()
-        return self.obj
-
-class FunctionMixin(PyobjMixin):
-    """ mixin for the code common to Function and Generator.
-    """
-
-    def setup(self):
-        """ perform setup for this test function. """
-        if hasattr(self, '_preservedparent'):
-            obj = self._preservedparent
-        elif isinstance(self.parent, Instance):
-            obj = self.parent.newinstance()
-            self.obj = self._getobj()
-        else:
-            obj = self.parent.obj
-        if inspect.ismethod(self.obj):
-            setup_name = 'setup_method'
-            teardown_name = 'teardown_method'
-        else:
-            setup_name = 'setup_function'
-            teardown_name = 'teardown_function'
-        setup_func_or_method = xunitsetup(obj, setup_name)
-        if setup_func_or_method is not None:
-            setup_func_or_method(self.obj)
-        fin = getattr(obj, teardown_name, None)
-        if fin is not None:
-            self.addfinalizer(lambda: fin(self.obj))
-
-    def _prunetraceback(self, excinfo):
-        if hasattr(self, '_obj') and not self.config.option.fulltrace:
-            code = _pytest._code.Code(get_real_func(self.obj))
-            path, firstlineno = code.path, code.firstlineno
-            traceback = excinfo.traceback
-            ntraceback = traceback.cut(path=path, firstlineno=firstlineno)
-            if ntraceback == traceback:
-                ntraceback = ntraceback.cut(path=path)
-                if ntraceback == traceback:
-                    #ntraceback = ntraceback.cut(excludepath=cutdir2)
-                    ntraceback = ntraceback.filter(filter_traceback)
-                    if not ntraceback:
-                        ntraceback = traceback
-
-            excinfo.traceback = ntraceback.filter()
-            # issue364: mark all but first and last frames to
-            # only show a single-line message for each frame
-            if self.config.option.tbstyle == "auto":
-                if len(excinfo.traceback) > 2:
-                    for entry in excinfo.traceback[1:-1]:
-                        entry.set_repr_style('short')
-
-    def _repr_failure_py(self, excinfo, style="long"):
-        if excinfo.errisinstance(pytest.fail.Exception):
-            if not excinfo.value.pytrace:
-                return py._builtin._totext(excinfo.value)
-        return super(FunctionMixin, self)._repr_failure_py(excinfo,
-            style=style)
-
-    def repr_failure(self, excinfo, outerr=None):
-        assert outerr is None, "XXX outerr usage is deprecated"
-        style = self.config.option.tbstyle
-        if style == "auto":
-            style = "long"
-        return self._repr_failure_py(excinfo, style=style)
-
-
-class Generator(FunctionMixin, PyCollector):
-    def collect(self):
-        # test generators are seen as collectors but they also
-        # invoke setup/teardown on popular request
-        # (induced by the common "test_*" naming shared with normal tests)
-        self.session._setupstate.prepare(self)
-        # see FunctionMixin.setup and test_setupstate_is_preserved_134
-        self._preservedparent = self.parent.obj
-        l = []
-        seen = {}
-        for i, x in enumerate(self.obj()):
-            name, call, args = self.getcallargs(x)
-            if not callable(call):
-                raise TypeError("%r yielded non callable test %r" %(self.obj, call,))
-            if name is None:
-                name = "[%d]" % i
-            else:
-                name = "['%s']" % name
-            if name in seen:
-                raise ValueError("%r generated tests with non-unique name %r" %(self, name))
-            seen[name] = True
-            l.append(self.Function(name, self, args=args, callobj=call))
-        return l
-
-    def getcallargs(self, obj):
-        if not isinstance(obj, (tuple, list)):
-            obj = (obj,)
-        # explict naming
-        if isinstance(obj[0], py.builtin._basestring):
-            name = obj[0]
-            obj = obj[1:]
-        else:
-            name = None
-        call, args = obj[0], obj[1:]
-        return name, call, args
-
-
-def hasinit(obj):
-    init = getattr(obj, '__init__', None)
-    if init:
-        if init != object.__init__:
-            return True
-
-
-
-def fillfixtures(function):
-    """ fill missing funcargs for a test function. """
-    try:
-        request = function._request
-    except AttributeError:
-        # XXX this special code path is only expected to execute
-        # with the oejskit plugin.  It uses classes with funcargs
-        # and we thus have to work a bit to allow this.
-        fm = function.session._fixturemanager
-        fi = fm.getfixtureinfo(function.parent, function.obj, None)
-        function._fixtureinfo = fi
-        request = function._request = FixtureRequest(function)
-        request._fillfixtures()
-        # prune out funcargs for jstests
-        newfuncargs = {}
-        for name in fi.argnames:
-            newfuncargs[name] = function.funcargs[name]
-        function.funcargs = newfuncargs
-    else:
-        request._fillfixtures()
-
-
-_notexists = object()
-
-class CallSpec2(object):
-    def __init__(self, metafunc):
-        self.metafunc = metafunc
-        self.funcargs = {}
-        self._idlist = []
-        self.params = {}
-        self._globalid = _notexists
-        self._globalid_args = set()
-        self._globalparam = _notexists
-        self._arg2scopenum = {}  # used for sorting parametrized resources
-        self.keywords = {}
-        self.indices = {}
-
-    def copy(self, metafunc):
-        cs = CallSpec2(self.metafunc)
-        cs.funcargs.update(self.funcargs)
-        cs.params.update(self.params)
-        cs.keywords.update(self.keywords)
-        cs.indices.update(self.indices)
-        cs._arg2scopenum.update(self._arg2scopenum)
-        cs._idlist = list(self._idlist)
-        cs._globalid = self._globalid
-        cs._globalid_args = self._globalid_args
-        cs._globalparam = self._globalparam
-        return cs
-
-    def _checkargnotcontained(self, arg):
-        if arg in self.params or arg in self.funcargs:
-            raise ValueError("duplicate %r" %(arg,))
-
-    def getparam(self, name):
-        try:
-            return self.params[name]
-        except KeyError:
-            if self._globalparam is _notexists:
-                raise ValueError(name)
-            return self._globalparam
-
-    @property
-    def id(self):
-        return "-".join(map(str, filter(None, self._idlist)))
-
-    def setmulti(self, valtypes, argnames, valset, id, keywords, scopenum,
-                 param_index):
-        for arg,val in zip(argnames, valset):
-            self._checkargnotcontained(arg)
-            valtype_for_arg = valtypes[arg]
-            getattr(self, valtype_for_arg)[arg] = val
-            self.indices[arg] = param_index
-            self._arg2scopenum[arg] = scopenum
-            if val is _notexists:
-                self._emptyparamspecified = True
-        self._idlist.append(id)
-        self.keywords.update(keywords)
-
-    def setall(self, funcargs, id, param):
-        for x in funcargs:
-            self._checkargnotcontained(x)
-        self.funcargs.update(funcargs)
-        if id is not _notexists:
-            self._idlist.append(id)
-        if param is not _notexists:
-            assert self._globalparam is _notexists
-            self._globalparam = param
-        for arg in funcargs:
-            self._arg2scopenum[arg] = scopenum_function
-
-
-class FuncargnamesCompatAttr:
-    """ helper class so that Metafunc, Function and FixtureRequest
-    don't need to each define the "funcargnames" compatibility attribute.
-    """
-    @property
-    def funcargnames(self):
-        """ alias attribute for ``fixturenames`` for pre-2.3 compatibility"""
-        return self.fixturenames
-
-class Metafunc(FuncargnamesCompatAttr):
-    """
-    Metafunc objects are passed to the ``pytest_generate_tests`` hook.
-    They help to inspect a test function and to generate tests according to
-    test configuration or values specified in the class or module where a
-    test function is defined.
-
-    :ivar fixturenames: set of fixture names required by the test function
-
-    :ivar function: underlying python test function
-
-    :ivar cls: class object where the test function is defined in or ``None``.
-
-    :ivar module: the module object where the test function is defined in.
-
-    :ivar config: access to the :class:`_pytest.config.Config` object for the
-        test session.
-
-    :ivar funcargnames:
-        .. deprecated:: 2.3
-            Use ``fixturenames`` instead.
-    """
-    def __init__(self, function, fixtureinfo, config, cls=None, module=None):
-        self.config = config
-        self.module = module
-        self.function = function
-        self.fixturenames = fixtureinfo.names_closure
-        self._arg2fixturedefs = fixtureinfo.name2fixturedefs
-        self.cls = cls
-        self._calls = []
-        self._ids = py.builtin.set()
-
-    def parametrize(self, argnames, argvalues, indirect=False, ids=None,
-        scope=None):
-        """ Add new invocations to the underlying test function using the list
-        of argvalues for the given argnames.  Parametrization is performed
-        during the collection phase.  If you need to setup expensive resources
-        see about setting indirect to do it rather at test setup time.
-
-        :arg argnames: a comma-separated string denoting one or more argument
-                       names, or a list/tuple of argument strings.
-
-        :arg argvalues: The list of argvalues determines how often a
-            test is invoked with different argument values.  If only one
-            argname was specified argvalues is a list of values.  If N
-            argnames were specified, argvalues must be a list of N-tuples,
-            where each tuple-element specifies a value for its respective
-            argname.
-
-        :arg indirect: The list of argnames or boolean. A list of arguments'
-            names (subset of argnames). If True the list contains all names from
-            the argnames. Each argvalue corresponding to an argname in this list will
-            be passed as request.param to its respective argname fixture
-            function so that it can perform more expensive setups during the
-            setup phase of a test rather than at collection time.
-
-        :arg ids: list of string ids, or a callable.
-            If strings, each is corresponding to the argvalues so that they are
-            part of the test id.
-            If callable, it should take one argument (a single argvalue) and return
-            a string or return None. If None, the automatically generated id for that
-            argument will be used.
-            If no ids are provided they will be generated automatically from
-            the argvalues.
-
-        :arg scope: if specified it denotes the scope of the parameters.
-            The scope is used for grouping tests by parameter instances.
-            It will also override any fixture-function defined scope, allowing
-            to set a dynamic scope using test context or configuration.
-        """
-
-        # individual parametrized argument sets can be wrapped in a series
-        # of markers in which case we unwrap the values and apply the mark
-        # at Function init
-        newkeywords = {}
-        unwrapped_argvalues = []
-        for i, argval in enumerate(argvalues):
-            while isinstance(argval, MarkDecorator):
-                newmark = MarkDecorator(argval.markname,
-                                        argval.args[:-1], argval.kwargs)
-                newmarks = newkeywords.setdefault(i, {})
-                newmarks[newmark.markname] = newmark
-                argval = argval.args[-1]
-            unwrapped_argvalues.append(argval)
-        argvalues = unwrapped_argvalues
-
-        if not isinstance(argnames, (tuple, list)):
-            argnames = [x.strip() for x in argnames.split(",") if x.strip()]
-            if len(argnames) == 1:
-                argvalues = [(val,) for val in argvalues]
-        if not argvalues:
-            argvalues = [(_notexists,) * len(argnames)]
-
-        if scope is None:
-            scope = "function"
-        scopenum = scopes.index(scope)
-        valtypes = {}
-        for arg in argnames:
-            if arg not in self.fixturenames:
-                raise ValueError("%r uses no fixture %r" %(self.function, arg))
-
-        if indirect is True:
-            valtypes = dict.fromkeys(argnames, "params")
-        elif indirect is False:
-            valtypes = dict.fromkeys(argnames, "funcargs")
-        elif isinstance(indirect, (tuple, list)):
-            valtypes = dict.fromkeys(argnames, "funcargs")
-            for arg in indirect:
-                if arg not in argnames:
-                    raise ValueError("indirect given to %r: fixture %r doesn't exist" %(
-                                     self.function, arg))
-                valtypes[arg] = "params"
-        idfn = None
-        if callable(ids):
-            idfn = ids
-            ids = None
-        if ids and len(ids) != len(argvalues):
-            raise ValueError('%d tests specified with %d ids' %(
-                             len(argvalues), len(ids)))
-        if not ids:
-            ids = idmaker(argnames, argvalues, idfn)
-        newcalls = []
-        for callspec in self._calls or [CallSpec2(self)]:
-            for param_index, valset in enumerate(argvalues):
-                assert len(valset) == len(argnames)
-                newcallspec = callspec.copy(self)
-                newcallspec.setmulti(valtypes, argnames, valset, ids[param_index],
-                                     newkeywords.get(param_index, {}), scopenum,
-                                     param_index)
-                newcalls.append(newcallspec)
-        self._calls = newcalls
-
-    def addcall(self, funcargs=None, id=_notexists, param=_notexists):
-        """ (deprecated, use parametrize) Add a new call to the underlying
-        test function during the collection phase of a test run.  Note that
-        request.addcall() is called during the test collection phase prior and
-        independently to actual test execution.  You should only use addcall()
-        if you need to specify multiple arguments of a test function.
-
-        :arg funcargs: argument keyword dictionary used when invoking
-            the test function.
-
-        :arg id: used for reporting and identification purposes.  If you
-            don't supply an `id` an automatic unique id will be generated.
-
-        :arg param: a parameter which will be exposed to a later fixture function
-            invocation through the ``request.param`` attribute.
-        """
-        assert funcargs is None or isinstance(funcargs, dict)
-        if funcargs is not None:
-            for name in funcargs:
-                if name not in self.fixturenames:
-                    pytest.fail("funcarg %r not used in this function." % name)
-        else:
-            funcargs = {}
-        if id is None:
-            raise ValueError("id=None not allowed")
-        if id is _notexists:
-            id = len(self._calls)
-        id = str(id)
-        if id in self._ids:
-            raise ValueError("duplicate id %r" % id)
-        self._ids.add(id)
-
-        cs = CallSpec2(self)
-        cs.setall(funcargs, id, param)
-        self._calls.append(cs)
-
-
-if _PY3:
-    import codecs
-
-    def _escape_bytes(val):
-        """
-        If val is pure ascii, returns it as a str(), otherwise escapes
-        into a sequence of escaped bytes:
-        b'\xc3\xb4\xc5\xd6' -> u'\\xc3\\xb4\\xc5\\xd6'
-
-        note:
-           the obvious "v.decode('unicode-escape')" will return
-           valid utf-8 unicode if it finds them in the string, but we
-           want to return escaped bytes for any byte, even if they match
-           a utf-8 string.
-        """
-        if val:
-            # source: http://goo.gl/bGsnwC
-            encoded_bytes, _ = codecs.escape_encode(val)
-            return encoded_bytes.decode('ascii')
-        else:
-            # empty bytes crashes codecs.escape_encode (#1087)
-            return ''
-else:
-    def _escape_bytes(val):
-        """
-        In py2 bytes and str are the same type, so return it unchanged if it
-        is a full ascii string, otherwise escape it into its binary form.
-        """
-        try:
-            return val.decode('ascii')
-        except UnicodeDecodeError:
-            return val.encode('string-escape')
-
-
-def _idval(val, argname, idx, idfn):
-    if idfn:
-        try:
-            s = idfn(val)
-            if s:
-                return s
-        except Exception:
-            pass
-
-    if isinstance(val, bytes):
-        return _escape_bytes(val)
-    elif isinstance(val, (float, int, str, bool, NoneType)):
-        return str(val)
-    elif isinstance(val, REGEX_TYPE):
-        return _escape_bytes(val.pattern) if isinstance(val.pattern, bytes) else val.pattern
-    elif enum is not None and isinstance(val, enum.Enum):
-        return str(val)
-    elif isclass(val) and hasattr(val, '__name__'):
-        return val.__name__
-    elif _PY2 and isinstance(val, unicode):
-        # special case for python 2: if a unicode string is
-        # convertible to ascii, return it as an str() object instead
-        try:
-            return str(val)
-        except UnicodeError:
-            # fallthrough
-            pass
-    return str(argname)+str(idx)
-
-def _idvalset(idx, valset, argnames, idfn):
-    this_id = [_idval(val, argname, idx, idfn)
-               for val, argname in zip(valset, argnames)]
-    return "-".join(this_id)
-
-def idmaker(argnames, argvalues, idfn=None):
-    ids = [_idvalset(valindex, valset, argnames, idfn)
-           for valindex, valset in enumerate(argvalues)]
-    if len(set(ids)) < len(ids):
-        # user may have provided a bad idfn which means the ids are not unique
-        ids = [str(i) + testid for i, testid in enumerate(ids)]
-    return ids
-
-def showfixtures(config):
-    from _pytest.main import wrap_session
-    return wrap_session(config, _showfixtures_main)
-
-def _showfixtures_main(config, session):
-    import _pytest.config
-    session.perform_collect()
-    curdir = py.path.local()
-    tw = _pytest.config.create_terminal_writer(config)
-    verbose = config.getvalue("verbose")
-
-    fm = session._fixturemanager
-
-    available = []
-    for argname, fixturedefs in fm._arg2fixturedefs.items():
-        assert fixturedefs is not None
-        if not fixturedefs:
-            continue
-        fixturedef = fixturedefs[-1]
-        loc = getlocation(fixturedef.func, curdir)
-        available.append((len(fixturedef.baseid),
-                          fixturedef.func.__module__,
-                          curdir.bestrelpath(loc),
-                          fixturedef.argname, fixturedef))
-
-    available.sort()
-    currentmodule = None
-    for baseid, module, bestrel, argname, fixturedef in available:
-        if currentmodule != module:
-            if not module.startswith("_pytest."):
-                tw.line()
-                tw.sep("-", "fixtures defined from %s" %(module,))
-                currentmodule = module
-        if verbose <= 0 and argname[0] == "_":
-            continue
-        if verbose > 0:
-            funcargspec = "%s -- %s" %(argname, bestrel,)
-        else:
-            funcargspec = argname
-        tw.line(funcargspec, green=True)
-        loc = getlocation(fixturedef.func, curdir)
-        doc = fixturedef.func.__doc__ or ""
-        if doc:
-            for line in doc.strip().split("\n"):
-                tw.line("    " + line.strip())
-        else:
-            tw.line("    %s: no docstring available" %(loc,),
-                red=True)
-
-def getlocation(function, curdir):
-    import inspect
-    fn = py.path.local(inspect.getfile(function))
-    lineno = py.builtin._getcode(function).co_firstlineno
-    if fn.relto(curdir):
-        fn = fn.relto(curdir)
-    return "%s:%d" %(fn, lineno+1)
-
-# builtin pytest.raises helper
-
-def raises(expected_exception, *args, **kwargs):
-    """ assert that a code block/function call raises ``expected_exception``
-    and raise a failure exception otherwise.
-
-    This helper produces a ``ExceptionInfo()`` object (see below).
-
-    If using Python 2.5 or above, you may use this function as a
-    context manager::
-
-        >>> with raises(ZeroDivisionError):
-        ...    1/0
-
-    .. note::
-
-       When using ``pytest.raises`` as a context manager, it's worthwhile to
-       note that normal context manager rules apply and that the exception
-       raised *must* be the final line in the scope of the context manager.
-       Lines of code after that, within the scope of the context manager will
-       not be executed. For example::
-
-           >>> with raises(OSError) as exc_info:
-                   assert 1 == 1  # this will execute as expected
-                   raise OSError(errno.EEXISTS, 'directory exists')
-                   assert exc_info.value.errno == errno.EEXISTS  # this will not execute
-
-       Instead, the following approach must be taken (note the difference in
-       scope)::
-
-           >>> with raises(OSError) as exc_info:
-                   assert 1 == 1  # this will execute as expected
-                   raise OSError(errno.EEXISTS, 'directory exists')
-
-               assert exc_info.value.errno == errno.EEXISTS  # this will now execute
-
-    Or you can specify a callable by passing a to-be-called lambda::
-
-        >>> raises(ZeroDivisionError, lambda: 1/0)
-        <ExceptionInfo ...>
-
-    or you can specify an arbitrary callable with arguments::
-
-        >>> def f(x): return 1/x
-        ...
-        >>> raises(ZeroDivisionError, f, 0)
-        <ExceptionInfo ...>
-        >>> raises(ZeroDivisionError, f, x=0)
-        <ExceptionInfo ...>
-
-    A third possibility is to use a string to be executed::
-
-        >>> raises(ZeroDivisionError, "f(0)")
-        <ExceptionInfo ...>
-
-    .. autoclass:: _pytest._code.ExceptionInfo
-        :members:
-
-    .. note::
-        Similar to caught exception objects in Python, explicitly clearing
-        local references to returned ``ExceptionInfo`` objects can
-        help the Python interpreter speed up its garbage collection.
-
-        Clearing those references breaks a reference cycle
-        (``ExceptionInfo`` --> caught exception --> frame stack raising
-        the exception --> current frame stack --> local variables -->
-        ``ExceptionInfo``) which makes Python keep all objects referenced
-        from that cycle (including all local variables in the current
-        frame) alive until the next cyclic garbage collection run. See the
-        official Python ``try`` statement documentation for more detailed
-        information.
-
-    """
-    __tracebackhide__ = True
-    if expected_exception is AssertionError:
-        # we want to catch a AssertionError
-        # replace our subclass with the builtin one
-        # see https://github.com/pytest-dev/pytest/issues/176
-        from _pytest.assertion.util import BuiltinAssertionError \
-            as expected_exception
-    msg = ("exceptions must be old-style classes or"
-           " derived from BaseException, not %s")
-    if isinstance(expected_exception, tuple):
-        for exc in expected_exception:
-            if not isclass(exc):
-                raise TypeError(msg % type(exc))
-    elif not isclass(expected_exception):
-        raise TypeError(msg % type(expected_exception))
-
-    if not args:
-        return RaisesContext(expected_exception)
-    elif isinstance(args[0], str):
-        code, = args
-        assert isinstance(code, str)
-        frame = sys._getframe(1)
-        loc = frame.f_locals.copy()
-        loc.update(kwargs)
-        #print "raises frame scope: %r" % frame.f_locals
-        try:
-            code = _pytest._code.Source(code).compile()
-            py.builtin.exec_(code, frame.f_globals, loc)
-            # XXX didn'T mean f_globals == f_locals something special?
-            #     this is destroyed here ...
-        except expected_exception:
-            return _pytest._code.ExceptionInfo()
-    else:
-        func = args[0]
-        try:
-            func(*args[1:], **kwargs)
-        except expected_exception:
-            return _pytest._code.ExceptionInfo()
-    pytest.fail("DID NOT RAISE {0}".format(expected_exception))
-
-class RaisesContext(object):
-    def __init__(self, expected_exception):
-        self.expected_exception = expected_exception
-        self.excinfo = None
-
-    def __enter__(self):
-        self.excinfo = object.__new__(_pytest._code.ExceptionInfo)
-        return self.excinfo
-
-    def __exit__(self, *tp):
-        __tracebackhide__ = True
-        if tp[0] is None:
-            pytest.fail("DID NOT RAISE")
-        if sys.version_info < (2, 7):
-            # py26: on __exit__() exc_value often does not contain the
-            # exception value.
-            # http://bugs.python.org/issue7853
-            if not isinstance(tp[1], BaseException):
-                exc_type, value, traceback = tp
-                tp = exc_type, exc_type(value), traceback
-        self.excinfo.__init__(tp)
-        return issubclass(self.excinfo.type, self.expected_exception)
-
-#
-#  the basic pytest Function item
-#
-
-class Function(FunctionMixin, pytest.Item, FuncargnamesCompatAttr):
-    """ a Function Item is responsible for setting up and executing a
-    Python test function.
-    """
-    _genid = None
-    def __init__(self, name, parent, args=None, config=None,
-                 callspec=None, callobj=NOTSET, keywords=None, session=None,
-                 fixtureinfo=None):
-        super(Function, self).__init__(name, parent, config=config,
-                                       session=session)
-        self._args = args
-        if callobj is not NOTSET:
-            self.obj = callobj
-
-        self.keywords.update(self.obj.__dict__)
-        if callspec:
-            self.callspec = callspec
-            self.keywords.update(callspec.keywords)
-        if keywords:
-            self.keywords.update(keywords)
-
-        if fixtureinfo is None:
-            fixtureinfo = self.session._fixturemanager.getfixtureinfo(
-                self.parent, self.obj, self.cls,
-                funcargs=not self._isyieldedfunction())
-        self._fixtureinfo = fixtureinfo
-        self.fixturenames = fixtureinfo.names_closure
-        self._initrequest()
-
-    def _initrequest(self):
-        self.funcargs = {}
-        if self._isyieldedfunction():
-            assert not hasattr(self, "callspec"), (
-                "yielded functions (deprecated) cannot have funcargs")
-        else:
-            if hasattr(self, "callspec"):
-                callspec = self.callspec
-                assert not callspec.funcargs
-                self._genid = callspec.id
-                if hasattr(callspec, "param"):
-                    self.param = callspec.param
-        self._request = FixtureRequest(self)
-
-    @property
-    def function(self):
-        "underlying python 'function' object"
-        return getattr(self.obj, 'im_func', self.obj)
-
-    def _getobj(self):
-        name = self.name
-        i = name.find("[") # parametrization
-        if i != -1:
-            name = name[:i]
-        return getattr(self.parent.obj, name)
-
-    @property
-    def _pyfuncitem(self):
-        "(compatonly) for code expecting pytest-2.2 style request objects"
-        return self
-
-    def _isyieldedfunction(self):
-        return getattr(self, "_args", None) is not None
-
-    def runtest(self):
-        """ execute the underlying test function. """
-        self.ihook.pytest_pyfunc_call(pyfuncitem=self)
-
-    def setup(self):
-        # check if parametrization happend with an empty list
-        try:
-            self.callspec._emptyparamspecified
-        except AttributeError:
-            pass
-        else:
-            fs, lineno = self._getfslineno()
-            pytest.skip("got empty parameter set, function %s at %s:%d" %(
-                self.function.__name__, fs, lineno))
-        super(Function, self).setup()
-        fillfixtures(self)
-
-
-scope2props = dict(session=())
-scope2props["module"] = ("fspath", "module")
-scope2props["class"] = scope2props["module"] + ("cls",)
-scope2props["instance"] = scope2props["class"] + ("instance", )
-scope2props["function"] = scope2props["instance"] + ("function", "keywords")
-
-def scopeproperty(name=None, doc=None):
-    def decoratescope(func):
-        scopename = name or func.__name__
-        def provide(self):
-            if func.__name__ in scope2props[self.scope]:
-                return func(self)
-            raise AttributeError("%s not available in %s-scoped context" % (
-                scopename, self.scope))
-        return property(provide, None, None, func.__doc__)
-    return decoratescope
-
-
-class FixtureRequest(FuncargnamesCompatAttr):
-    """ A request for a fixture from a test or fixture function.
-
-    A request object gives access to the requesting test context
-    and has an optional ``param`` attribute in case
-    the fixture is parametrized indirectly.
-    """
-
-    def __init__(self, pyfuncitem):
-        self._pyfuncitem = pyfuncitem
-        #: fixture for which this request is being performed
-        self.fixturename = None
-        #: Scope string, one of "function", "cls", "module", "session"
-        self.scope = "function"
-        self._funcargs  = {}
-        self._fixturedefs = {}
-        fixtureinfo = pyfuncitem._fixtureinfo
-        self._arg2fixturedefs = fixtureinfo.name2fixturedefs.copy()
-        self._arg2index = {}
-        self.fixturenames = fixtureinfo.names_closure
-        self._fixturemanager = pyfuncitem.session._fixturemanager
-
-    @property
-    def node(self):
-        """ underlying collection node (depends on current request scope)"""
-        return self._getscopeitem(self.scope)
-
-
-    def _getnextfixturedef(self, argname):
-        fixturedefs = self._arg2fixturedefs.get(argname, None)
-        if fixturedefs is None:
-            # we arrive here because of a  a dynamic call to
-            # getfuncargvalue(argname) usage which was naturally
-            # not known at parsing/collection time
-            fixturedefs = self._fixturemanager.getfixturedefs(
-                            argname, self._pyfuncitem.parent.nodeid)
-            self._arg2fixturedefs[argname] = fixturedefs
-        # fixturedefs list is immutable so we maintain a decreasing index
-        index = self._arg2index.get(argname, 0) - 1
-        if fixturedefs is None or (-index > len(fixturedefs)):
-            raise FixtureLookupError(argname, self)
-        self._arg2index[argname] = index
-        return fixturedefs[index]
-
-    @property
-    def config(self):
-        """ the pytest config object associated with this request. """
-        return self._pyfuncitem.config
-
-
-    @scopeproperty()
-    def function(self):
-        """ test function object if the request has a per-function scope. """
-        return self._pyfuncitem.obj
-
-    @scopeproperty("class")
-    def cls(self):
-        """ class (can be None) where the test function was collected. """
-        clscol = self._pyfuncitem.getparent(pytest.Class)
-        if clscol:
-            return clscol.obj
-
-    @property
-    def instance(self):
-        """ instance (can be None) on which test function was collected. """
-        # unittest support hack, see _pytest.unittest.TestCaseFunction
-        try:
-            return self._pyfuncitem._testcase
-        except AttributeError:
-            function = getattr(self, "function", None)
-            if function is not None:
-                return py.builtin._getimself(function)
-
-    @scopeproperty()
-    def module(self):
-        """ python module object where the test function was collected. """
-        return self._pyfuncitem.getparent(pytest.Module).obj
-
-    @scopeproperty()
-    def fspath(self):
-        """ the file system path of the test module which collected this test. """
-        return self._pyfuncitem.fspath
-
-    @property
-    def keywords(self):
-        """ keywords/markers dictionary for the underlying node. """
-        return self.node.keywords
-
-    @property
-    def session(self):
-        """ pytest session object. """
-        return self._pyfuncitem.session
-
-    def addfinalizer(self, finalizer):
-        """ add finalizer/teardown function to be called after the
-        last test within the requesting test context finished
-        execution. """
-        # XXX usually this method is shadowed by fixturedef specific ones
-        self._addfinalizer(finalizer, scope=self.scope)
-
-    def _addfinalizer(self, finalizer, scope):
-        colitem = self._getscopeitem(scope)
-        self._pyfuncitem.session._setupstate.addfinalizer(
-            finalizer=finalizer, colitem=colitem)
-
-    def applymarker(self, marker):
-        """ Apply a marker to a single test function invocation.
-        This method is useful if you don't want to have a keyword/marker
-        on all function invocations.
-
-        :arg marker: a :py:class:`_pytest.mark.MarkDecorator` object
-            created by a call to ``pytest.mark.NAME(...)``.
-        """
-        try:
-            self.node.keywords[marker.markname] = marker
-        except AttributeError:
-            raise ValueError(marker)
-
-    def raiseerror(self, msg):
-        """ raise a FixtureLookupError with the given message. """
-        raise self._fixturemanager.FixtureLookupError(None, self, msg)
-
-    def _fillfixtures(self):
-        item = self._pyfuncitem
-        fixturenames = getattr(item, "fixturenames", self.fixturenames)
-        for argname in fixturenames:
-            if argname not in item.funcargs:
-                item.funcargs[argname] = self.getfuncargvalue(argname)
-
-    def cached_setup(self, setup, teardown=None, scope="module", extrakey=None):
-        """ (deprecated) Return a testing resource managed by ``setup`` &
-        ``teardown`` calls.  ``scope`` and ``extrakey`` determine when the
-        ``teardown`` function will be called so that subsequent calls to
-        ``setup`` would recreate the resource.  With pytest-2.3 you often
-        do not need ``cached_setup()`` as you can directly declare a scope
-        on a fixture function and register a finalizer through
-        ``request.addfinalizer()``.
-
-        :arg teardown: function receiving a previously setup resource.
-        :arg setup: a no-argument function creating a resource.
-        :arg scope: a string value out of ``function``, ``class``, ``module``
-            or ``session`` indicating the caching lifecycle of the resource.
-        :arg extrakey: added to internal caching key of (funcargname, scope).
-        """
-        if not hasattr(self.config, '_setupcache'):
-            self.config._setupcache = {} # XXX weakref?
-        cachekey = (self.fixturename, self._getscopeitem(scope), extrakey)
-        cache = self.config._setupcache
-        try:
-            val = cache[cachekey]
-        except KeyError:
-            self._check_scope(self.fixturename, self.scope, scope)
-            val = setup()
-            cache[cachekey] = val
-            if teardown is not None:
-                def finalizer():
-                    del cache[cachekey]
-                    teardown(val)
-                self._addfinalizer(finalizer, scope=scope)
-        return val
-
-    def getfuncargvalue(self, argname):
-        """ Dynamically retrieve a named fixture function argument.
-
-        As of pytest-2.3, it is easier and usually better to access other
-        fixture values by stating it as an input argument in the fixture
-        function.  If you only can decide about using another fixture at test
-        setup time, you may use this function to retrieve it inside a fixture
-        function body.
-        """
-        return self._get_active_fixturedef(argname).cached_result[0]
-
-    def _get_active_fixturedef(self, argname):
-        try:
-            return self._fixturedefs[argname]
-        except KeyError:
-            try:
-                fixturedef = self._getnextfixturedef(argname)
-            except FixtureLookupError:
-                if argname == "request":
-                    class PseudoFixtureDef:
-                        cached_result = (self, [0], None)
-                        scope = "function"
-                    return PseudoFixtureDef
-                raise
-        # remove indent to prevent the python3 exception
-        # from leaking into the call
-        result = self._getfuncargvalue(fixturedef)
-        self._funcargs[argname] = result
-        self._fixturedefs[argname] = fixturedef
-        return fixturedef
-
-    def _get_fixturestack(self):
-        current = self
-        l = []
-        while 1:
-            fixturedef = getattr(current, "_fixturedef", None)
-            if fixturedef is None:
-                l.reverse()
-                return l
-            l.append(fixturedef)
-            current = current._parent_request
-
-    def _getfuncargvalue(self, fixturedef):
-        # prepare a subrequest object before calling fixture function
-        # (latter managed by fixturedef)
-        argname = fixturedef.argname
-        funcitem = self._pyfuncitem
-        scope = fixturedef.scope
-        try:
-            param = funcitem.callspec.getparam(argname)
-        except (AttributeError, ValueError):
-            param = NOTSET
-            param_index = 0
-        else:
-            # indices might not be set if old-style metafunc.addcall() was used
-            param_index = funcitem.callspec.indices.get(argname, 0)
-            # if a parametrize invocation set a scope it will override
-            # the static scope defined with the fixture function
-            paramscopenum = funcitem.callspec._arg2scopenum.get(argname)
-            if paramscopenum is not None:
-                scope = scopes[paramscopenum]
-
-        subrequest = SubRequest(self, scope, param, param_index, fixturedef)
-
-        # check if a higher-level scoped fixture accesses a lower level one
-        subrequest._check_scope(argname, self.scope, scope)
-
-        # clear sys.exc_info before invoking the fixture (python bug?)
-        # if its not explicitly cleared it will leak into the call
-        exc_clear()
-        try:
-            # call the fixture function
-            val = fixturedef.execute(request=subrequest)
-        finally:
-            # if fixture function failed it might have registered finalizers
-            self.session._setupstate.addfinalizer(fixturedef.finish,
-                                                  subrequest.node)
-        return val
-
-    def _check_scope(self, argname, invoking_scope, requested_scope):
-        if argname == "request":
-            return
-        if scopemismatch(invoking_scope, requested_scope):
-            # try to report something helpful
-            lines = self._factorytraceback()
-            pytest.fail("ScopeMismatch: You tried to access the %r scoped "
-                "fixture %r with a %r scoped request object, "
-                "involved factories\n%s" %(
-                (requested_scope, argname, invoking_scope, "\n".join(lines))),
-                pytrace=False)
-
-    def _factorytraceback(self):
-        lines = []
-        for fixturedef in self._get_fixturestack():
-            factory = fixturedef.func
-            fs, lineno = getfslineno(factory)
-            p = self._pyfuncitem.session.fspath.bestrelpath(fs)
-            args = _format_args(factory)
-            lines.append("%s:%d:  def %s%s" %(
-                p, lineno, factory.__name__, args))
-        return lines
-
-    def _getscopeitem(self, scope):
-        if scope == "function":
-            # this might also be a non-function Item despite its attribute name
-            return self._pyfuncitem
-        node = get_scope_node(self._pyfuncitem, scope)
-        if node is None and scope == "class":
-            # fallback to function item itself
-            node = self._pyfuncitem
-        assert node
-        return node
-
-    def __repr__(self):
-        return "<FixtureRequest for %r>" %(self.node)
-
-
-class SubRequest(FixtureRequest):
-    """ a sub request for handling getting a fixture from a
-    test function/fixture. """
-    def __init__(self, request, scope, param, param_index, fixturedef):
-        self._parent_request = request
-        self.fixturename = fixturedef.argname
-        if param is not NOTSET:
-            self.param = param
-        self.param_index = param_index
-        self.scope = scope
-        self._fixturedef = fixturedef
-        self.addfinalizer = fixturedef.addfinalizer
-        self._pyfuncitem = request._pyfuncitem
-        self._funcargs  = request._funcargs
-        self._fixturedefs = request._fixturedefs
-        self._arg2fixturedefs = request._arg2fixturedefs
-        self._arg2index = request._arg2index
-        self.fixturenames = request.fixturenames
-        self._fixturemanager = request._fixturemanager
-
-    def __repr__(self):
-        return "<SubRequest %r for %r>" % (self.fixturename, self._pyfuncitem)
-
-
-class ScopeMismatchError(Exception):
-    """ A fixture function tries to use a different fixture function which
-    which has a lower scope (e.g. a Session one calls a function one)
-    """
-
-scopes = "session module class function".split()
-scopenum_function = scopes.index("function")
-def scopemismatch(currentscope, newscope):
-    return scopes.index(newscope) > scopes.index(currentscope)
-
-
-class FixtureLookupError(LookupError):
-    """ could not return a requested Fixture (missing or invalid). """
-    def __init__(self, argname, request, msg=None):
-        self.argname = argname
-        self.request = request
-        self.fixturestack = request._get_fixturestack()
-        self.msg = msg
-
-    def formatrepr(self):
-        tblines = []
-        addline = tblines.append
-        stack = [self.request._pyfuncitem.obj]
-        stack.extend(map(lambda x: x.func, self.fixturestack))
-        msg = self.msg
-        if msg is not None:
-            # the last fixture raise an error, let's present
-            # it at the requesting side
-            stack = stack[:-1]
-        for function in stack:
-            fspath, lineno = getfslineno(function)
-            try:
-                lines, _ = inspect.getsourcelines(get_real_func(function))
-            except (IOError, IndexError):
-                error_msg = "file %s, line %s: source code not available"
-                addline(error_msg % (fspath, lineno+1))
-            else:
-                addline("file %s, line %s" % (fspath, lineno+1))
-                for i, line in enumerate(lines):
-                    line = line.rstrip()
-                    addline("  " + line)
-                    if line.lstrip().startswith('def'):
-                        break
-
-        if msg is None:
-            fm = self.request._fixturemanager
-            available = []
-            for name, fixturedef in fm._arg2fixturedefs.items():
-                parentid = self.request._pyfuncitem.parent.nodeid
-                faclist = list(fm._matchfactories(fixturedef, parentid))
-                if faclist:
-                    available.append(name)
-            msg = "fixture %r not found" % (self.argname,)
-            msg += "\n available fixtures: %s" %(", ".join(available),)
-            msg += "\n use 'py.test --fixtures [testpath]' for help on them."
-
-        return FixtureLookupErrorRepr(fspath, lineno, tblines, msg, self.argname)
-
-class FixtureLookupErrorRepr(TerminalRepr):
-    def __init__(self, filename, firstlineno, tblines, errorstring, argname):
-        self.tblines = tblines
-        self.errorstring = errorstring
-        self.filename = filename
-        self.firstlineno = firstlineno
-        self.argname = argname
-
-    def toterminal(self, tw):
-        #tw.line("FixtureLookupError: %s" %(self.argname), red=True)
-        for tbline in self.tblines:
-            tw.line(tbline.rstrip())
-        for line in self.errorstring.split("\n"):
-            tw.line("        " + line.strip(), red=True)
-        tw.line()
-        tw.line("%s:%d" % (self.filename, self.firstlineno+1))
-
-class FixtureManager:
-    """
-    pytest fixtures definitions and information is stored and managed
-    from this class.
-
-    During collection fm.parsefactories() is called multiple times to parse
-    fixture function definitions into FixtureDef objects and internal
-    data structures.
-
-    During collection of test functions, metafunc-mechanics instantiate
-    a FuncFixtureInfo object which is cached per node/func-name.
-    This FuncFixtureInfo object is later retrieved by Function nodes
-    which themselves offer a fixturenames attribute.
-
-    The FuncFixtureInfo object holds information about fixtures and FixtureDefs
-    relevant for a particular function.  An initial list of fixtures is
-    assembled like this:
-
-    - ini-defined usefixtures
-    - autouse-marked fixtures along the collection chain up from the function
-    - usefixtures markers at module/class/function level
-    - test function funcargs
-
-    Subsequently the funcfixtureinfo.fixturenames attribute is computed
-    as the closure of the fixtures needed to setup the initial fixtures,
-    i. e. fixtures needed by fixture functions themselves are appended
-    to the fixturenames list.
-
-    Upon the test-setup phases all fixturenames are instantiated, retrieved
-    by a lookup of their FuncFixtureInfo.
-    """
-
-    _argprefix = "pytest_funcarg__"
-    FixtureLookupError = FixtureLookupError
-    FixtureLookupErrorRepr = FixtureLookupErrorRepr
-
-    def __init__(self, session):
-        self.session = session
-        self.config = session.config
-        self._arg2fixturedefs = {}
-        self._holderobjseen = set()
-        self._arg2finish = {}
-        self._nodeid_and_autousenames = [("", self.config.getini("usefixtures"))]
-        session.config.pluginmanager.register(self, "funcmanage")
-
-
-    def getfixtureinfo(self, node, func, cls, funcargs=True):
-        if funcargs and not hasattr(node, "nofuncargs"):
-            if cls is not None:
-                startindex = 1
-            else:
-                startindex = None
-            argnames = getfuncargnames(func, startindex)
-        else:
-            argnames = ()
-        usefixtures = getattr(func, "usefixtures", None)
-        initialnames = argnames
-        if usefixtures is not None:
-            initialnames = usefixtures.args + initialnames
-        fm = node.session._fixturemanager
-        names_closure, arg2fixturedefs = fm.getfixtureclosure(initialnames,
-                                                              node)
-        return FuncFixtureInfo(argnames, names_closure, arg2fixturedefs)
-
-    def pytest_plugin_registered(self, plugin):
-        nodeid = None
-        try:
-            p = py.path.local(plugin.__file__)
-        except AttributeError:
-            pass
-        else:
-            # construct the base nodeid which is later used to check
-            # what fixtures are visible for particular tests (as denoted
-            # by their test id)
-            if p.basename.startswith("conftest.py"):
-                nodeid = p.dirpath().relto(self.config.rootdir)
-                if p.sep != "/":
-                    nodeid = nodeid.replace(p.sep, "/")
-        self.parsefactories(plugin, nodeid)
-
-    def _getautousenames(self, nodeid):
-        """ return a tuple of fixture names to be used. """
-        autousenames = []
-        for baseid, basenames in self._nodeid_and_autousenames:
-            if nodeid.startswith(baseid):
-                if baseid:
-                    i = len(baseid)
-                    nextchar = nodeid[i:i+1]
-                    if nextchar and nextchar not in ":/":
-                        continue
-                autousenames.extend(basenames)
-        # make sure autousenames are sorted by scope, scopenum 0 is session
-        autousenames.sort(
-            key=lambda x: self._arg2fixturedefs[x][-1].scopenum)
-        return autousenames
-
-    def getfixtureclosure(self, fixturenames, parentnode):
-        # collect the closure of all fixtures , starting with the given
-        # fixturenames as the initial set.  As we have to visit all
-        # factory definitions anyway, we also return a arg2fixturedefs
-        # mapping so that the caller can reuse it and does not have
-        # to re-discover fixturedefs again for each fixturename
-        # (discovering matching fixtures for a given name/node is expensive)
-
-        parentid = parentnode.nodeid
-        fixturenames_closure = self._getautousenames(parentid)
-        def merge(otherlist):
-            for arg in otherlist:
-                if arg not in fixturenames_closure:
-                    fixturenames_closure.append(arg)
-        merge(fixturenames)
-        arg2fixturedefs = {}
-        lastlen = -1
-        while lastlen != len(fixturenames_closure):
-            lastlen = len(fixturenames_closure)
-            for argname in fixturenames_closure:
-                if argname in arg2fixturedefs:
-                    continue
-                fixturedefs = self.getfixturedefs(argname, parentid)
-                if fixturedefs:
-                    arg2fixturedefs[argname] = fixturedefs
-                    merge(fixturedefs[-1].argnames)
-        return fixturenames_closure, arg2fixturedefs
-
-    def pytest_generate_tests(self, metafunc):
-        for argname in metafunc.fixturenames:
-            faclist = metafunc._arg2fixturedefs.get(argname)
-            if faclist:
-                fixturedef = faclist[-1]
-                if fixturedef.params is not None:
-                    func_params = getattr(getattr(metafunc.function, 'parametrize', None), 'args', [[None]])
-                    # skip directly parametrized arguments
-                    argnames = func_params[0]
-                    if not isinstance(argnames, (tuple, list)):
-                        argnames = [x.strip() for x in argnames.split(",") if x.strip()]
-                    if argname not in func_params and argname not in argnames:
-                        metafunc.parametrize(argname, fixturedef.params,
-                                             indirect=True, scope=fixturedef.scope,
-                                             ids=fixturedef.ids)
-            else:
-                continue # will raise FixtureLookupError at setup time
-
-    def pytest_collection_modifyitems(self, items):
-        # separate parametrized setups
-        items[:] = reorder_items(items)
-
-    def parsefactories(self, node_or_obj, nodeid=NOTSET, unittest=False):
-        if nodeid is not NOTSET:
-            holderobj = node_or_obj
-        else:
-            holderobj = node_or_obj.obj
-            nodeid = node_or_obj.nodeid
-        if holderobj in self._holderobjseen:
-            return
-        self._holderobjseen.add(holderobj)
-        autousenames = []
-        for name in dir(holderobj):
-            obj = getattr(holderobj, name, None)
-            # fixture functions have a pytest_funcarg__ prefix (pre-2.3 style)
-            # or are "@pytest.fixture" marked
-            marker = getfixturemarker(obj)
-            if marker is None:
-                if not name.startswith(self._argprefix):
-                    continue
-                if not callable(obj):
-                    continue
-                marker = defaultfuncargprefixmarker
-                name = name[len(self._argprefix):]
-            elif not isinstance(marker, FixtureFunctionMarker):
-                # magic globals  with __getattr__ might have got us a wrong
-                # fixture attribute
-                continue
-            else:
-                assert not name.startswith(self._argprefix)
-            fixturedef = FixtureDef(self, nodeid, name, obj,
-                                    marker.scope, marker.params,
-                                    yieldctx=marker.yieldctx,
-                                    unittest=unittest, ids=marker.ids)
-            faclist = self._arg2fixturedefs.setdefault(name, [])
-            if fixturedef.has_location:
-                faclist.append(fixturedef)
-            else:
-                # fixturedefs with no location are at the front
-                # so this inserts the current fixturedef after the
-                # existing fixturedefs from external plugins but
-                # before the fixturedefs provided in conftests.
-                i = len([f for f in faclist if not f.has_location])
-                faclist.insert(i, fixturedef)
-            if marker.autouse:
-                autousenames.append(name)
-        if autousenames:
-            self._nodeid_and_autousenames.append((nodeid or '', autousenames))
-
-    def getfixturedefs(self, argname, nodeid):
-        try:
-            fixturedefs = self._arg2fixturedefs[argname]
-        except KeyError:
-            return None
-        else:
-            return tuple(self._matchfactories(fixturedefs, nodeid))
-
-    def _matchfactories(self, fixturedefs, nodeid):
-        for fixturedef in fixturedefs:
-            if nodeid.startswith(fixturedef.baseid):
-                yield fixturedef
-
-
-def fail_fixturefunc(fixturefunc, msg):
-    fs, lineno = getfslineno(fixturefunc)
-    location = "%s:%s" % (fs, lineno+1)
-    source = _pytest._code.Source(fixturefunc)
-    pytest.fail(msg + ":\n\n" + str(source.indent()) + "\n" + location,
-                pytrace=False)
-
-def call_fixture_func(fixturefunc, request, kwargs, yieldctx):
-    if yieldctx:
-        if not is_generator(fixturefunc):
-            fail_fixturefunc(fixturefunc,
-                msg="yield_fixture requires yield statement in function")
-        iter = fixturefunc(**kwargs)
-        next = getattr(iter, "__next__", None)
-        if next is None:
-            next = getattr(iter, "next")
-        res = next()
-        def teardown():
-            try:
-                next()
-            except StopIteration:
-                pass
-            else:
-                fail_fixturefunc(fixturefunc,
-                    "yield_fixture function has more than one 'yield'")
-        request.addfinalizer(teardown)
-    else:
-        if is_generator(fixturefunc):
-            fail_fixturefunc(fixturefunc,
-                msg="pytest.fixture functions cannot use ``yield``. "
-                    "Instead write and return an inner function/generator "
-                    "and let the consumer call and iterate over it.")
-        res = fixturefunc(**kwargs)
-    return res
-
-class FixtureDef:
-    """ A container for a factory definition. """
-    def __init__(self, fixturemanager, baseid, argname, func, scope, params,
-                 yieldctx, unittest=False, ids=None):
-        self._fixturemanager = fixturemanager
-        self.baseid = baseid or ''
-        self.has_location = baseid is not None
-        self.func = func
-        self.argname = argname
-        self.scope = scope
-        self.scopenum = scopes.index(scope or "function")
-        self.params = params
-        startindex = unittest and 1 or None
-        self.argnames = getfuncargnames(func, startindex=startindex)
-        self.yieldctx = yieldctx
-        self.unittest = unittest
-        self.ids = ids
-        self._finalizer = []
-
-    def addfinalizer(self, finalizer):
-        self._finalizer.append(finalizer)
-
-    def finish(self):
-        try:
-            while self._finalizer:
-                func = self._finalizer.pop()
-                func()
-        finally:
-            # even if finalization fails, we invalidate
-            # the cached fixture value
-            if hasattr(self, "cached_result"):
-                del self.cached_result
-
-    def execute(self, request):
-        # get required arguments and register our own finish()
-        # with their finalization
-        kwargs = {}
-        for argname in self.argnames:
-            fixturedef = request._get_active_fixturedef(argname)
-            result, arg_cache_key, exc = fixturedef.cached_result
-            request._check_scope(argname, request.scope, fixturedef.scope)
-            kwargs[argname] = result
-            if argname != "request":
-                fixturedef.addfinalizer(self.finish)
-
-        my_cache_key = request.param_index
-        cached_result = getattr(self, "cached_result", None)
-        if cached_result is not None:
-            result, cache_key, err = cached_result
-            if my_cache_key == cache_key:
-                if err is not None:
-                    py.builtin._reraise(*err)
-                else:
-                    return result
-            # we have a previous but differently parametrized fixture instance
-            # so we need to tear it down before creating a new one
-            self.finish()
-            assert not hasattr(self, "cached_result")
-
-        fixturefunc = self.func
-
-        if self.unittest:
-            if request.instance is not None:
-                # bind the unbound method to the TestCase instance
-                fixturefunc = self.func.__get__(request.instance)
-        else:
-            # the fixture function needs to be bound to the actual
-            # request.instance so that code working with "self" behaves
-            # as expected.
-            if request.instance is not None:
-                fixturefunc = getimfunc(self.func)
-                if fixturefunc != self.func:
-                    fixturefunc = fixturefunc.__get__(request.instance)
-
-        try:
-            result = call_fixture_func(fixturefunc, request, kwargs,
-                                       self.yieldctx)
-        except Exception:
-            self.cached_result = (None, my_cache_key, sys.exc_info())
-            raise
-        self.cached_result = (result, my_cache_key, None)
-        return result
-
-    def __repr__(self):
-        return ("<FixtureDef name=%r scope=%r baseid=%r >" %
-                (self.argname, self.scope, self.baseid))
-
-def num_mock_patch_args(function):
-    """ return number of arguments used up by mock arguments (if any) """
-    patchings = getattr(function, "patchings", None)
-    if not patchings:
-        return 0
-    mock = sys.modules.get("mock", sys.modules.get("unittest.mock", None))
-    if mock is not None:
-        return len([p for p in patchings
-                        if not p.attribute_name and p.new is mock.DEFAULT])
-    return len(patchings)
-
-
-def getfuncargnames(function, startindex=None):
-    # XXX merge with main.py's varnames
-    #assert not isclass(function)
-    realfunction = function
-    while hasattr(realfunction, "__wrapped__"):
-        realfunction = realfunction.__wrapped__
-    if startindex is None:
-        startindex = inspect.ismethod(function) and 1 or 0
-    if realfunction != function:
-        startindex += num_mock_patch_args(function)
-        function = realfunction
-    if isinstance(function, functools.partial):
-        argnames = inspect.getargs(_pytest._code.getrawcode(function.func))[0]
-        partial = function
-        argnames = argnames[len(partial.args):]
-        if partial.keywords:
-            for kw in partial.keywords:
-                argnames.remove(kw)
-    else:
-        argnames = inspect.getargs(_pytest._code.getrawcode(function))[0]
-    defaults = getattr(function, 'func_defaults',
-                       getattr(function, '__defaults__', None)) or ()
-    numdefaults = len(defaults)
-    if numdefaults:
-        return tuple(argnames[startindex:-numdefaults])
-    return tuple(argnames[startindex:])
-
-# algorithm for sorting on a per-parametrized resource setup basis
-# it is called for scopenum==0 (session) first and performs sorting
-# down to the lower scopes such as to minimize number of "high scope"
-# setups and teardowns
-
-def reorder_items(items):
-    argkeys_cache = {}
-    for scopenum in range(0, scopenum_function):
-        argkeys_cache[scopenum] = d = {}
-        for item in items:
-            keys = set(get_parametrized_fixture_keys(item, scopenum))
-            if keys:
-                d[item] = keys
-    return reorder_items_atscope(items, set(), argkeys_cache, 0)
-
-def reorder_items_atscope(items, ignore, argkeys_cache, scopenum):
-    if scopenum >= scopenum_function or len(items) < 3:
-        return items
-    items_done = []
-    while 1:
-        items_before, items_same, items_other, newignore = \
-                slice_items(items, ignore, argkeys_cache[scopenum])
-        items_before = reorder_items_atscope(
-                            items_before, ignore, argkeys_cache,scopenum+1)
-        if items_same is None:
-            # nothing to reorder in this scope
-            assert items_other is None
-            return items_done + items_before
-        items_done.extend(items_before)
-        items = items_same + items_other
-        ignore = newignore
-
-
-def slice_items(items, ignore, scoped_argkeys_cache):
-    # we pick the first item which uses a fixture instance in the
-    # requested scope and which we haven't seen yet.  We slice the input
-    # items list into a list of items_nomatch, items_same and
-    # items_other
-    if scoped_argkeys_cache:  # do we need to do work at all?
-        it = iter(items)
-        # first find a slicing key
-        for i, item in enumerate(it):
-            argkeys = scoped_argkeys_cache.get(item)
-            if argkeys is not None:
-                argkeys = argkeys.difference(ignore)
-                if argkeys:  # found a slicing key
-                    slicing_argkey = argkeys.pop()
-                    items_before = items[:i]
-                    items_same = [item]
-                    items_other = []
-                    # now slice the remainder of the list
-                    for item in it:
-                        argkeys = scoped_argkeys_cache.get(item)
-                        if argkeys and slicing_argkey in argkeys and \
-                            slicing_argkey not in ignore:
-                            items_same.append(item)
-                        else:
-                            items_other.append(item)
-                    newignore = ignore.copy()
-                    newignore.add(slicing_argkey)
-                    return (items_before, items_same, items_other, newignore)
-    return items, None, None, None
-
-def get_parametrized_fixture_keys(item, scopenum):
-    """ return list of keys for all parametrized arguments which match
-    the specified scope. """
-    assert scopenum < scopenum_function  # function
-    try:
-        cs = item.callspec
-    except AttributeError:
-        pass
-    else:
-        # cs.indictes.items() is random order of argnames but
-        # then again different functions (items) can change order of
-        # arguments so it doesn't matter much probably
-        for argname, param_index in cs.indices.items():
-            if cs._arg2scopenum[argname] != scopenum:
-                continue
-            if scopenum == 0:    # session
-                key = (argname, param_index)
-            elif scopenum == 1:  # module
-                key = (argname, param_index, item.fspath)
-            elif scopenum == 2:  # class
-                key = (argname, param_index, item.fspath, item.cls)
-            yield key
-
-
-def xunitsetup(obj, name):
-    meth = getattr(obj, name, None)
-    if getfixturemarker(meth) is None:
-        return meth
-
-def getfixturemarker(obj):
-    """ return fixturemarker or None if it doesn't exist or raised
-    exceptions."""
-    try:
-        return getattr(obj, "_pytestfixturefunction", None)
-    except KeyboardInterrupt:
-        raise
-    except Exception:
-        # some objects raise errors like request (from flask import request)
-        # we don't expect them to be fixture functions
-        return None
-
-scopename2class = {
-    'class': Class,
-    'module': Module,
-    'function': pytest.Item,
-}
-def get_scope_node(node, scope):
-    cls = scopename2class.get(scope)
-    if cls is None:
-        if scope == "session":
-            return node.session
-        raise ValueError("unknown scope")
-    return node.getparent(cls)