Add m-esr52 at 52.6.0

1 files changed, 2300 insertions, 0 deletions

diff --git a/python/pytest/_pytest/python.py b/python/pytest/_pytest/python.py
new file mode 100644
index 000000000..21d78aea3
--- /dev/null
+++ b/python/pytest/_pytest/python.py
@@ -0,0 +1,2300 @@
+""" 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
+        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)]
+            # we passed a empty list to parameterize, skip that test
+            #
+            fs, lineno = getfslineno(self.function)
+            newmark = pytest.mark.skip(
+                reason="got empty parameter set %r, function %s at %s:%d" % (
+                    argnames, self.function.__name__, fs, lineno))
+            newmarks = newkeywords.setdefault(0, {})
+            newmarks[newmark.markname] = newmark
+
+
+        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
+        for fixturedef in fixturedefs:
+            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):
+        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", "class", "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)