Source code for _pytest.python

""" Python test discovery, setup and run of test functions. """
import py
import inspect
import sys
import pytest
from py._code.code import TerminalRepr

import _pytest
cutdir = py.path.local(_pytest.__file__).dirpath()

def pytest_addoption(parser):
    group = parser.getgroup("general")
    group.addoption('--funcargs',
               action="store_true", dest="showfuncargs", default=False,
               help="show available function arguments, sorted by plugin")

def pytest_cmdline_main(config):
    if config.option.showfuncargs:
        showfuncargs(config)
        return 0

def pytest_namespace(__multicall__):
    __multicall__.execute()
    raises.Exception = pytest.fail.Exception
    return {
        'raises' : raises,
        'collect': {
        'Module': Module, 'Class': Class, 'Instance': Instance,
        'Function': Function, 'Generator': Generator,
        '_fillfuncargs': fillfuncargs}
    }

def pytest_funcarg__pytestconfig(request):
    """ the pytest config object with access to command line opts."""
    return request.config

def pytest_pyfunc_call(__multicall__, pyfuncitem):
    if not __multicall__.execute():
        testfunction = pyfuncitem.obj
        if pyfuncitem._isyieldedfunction():
            testfunction(*pyfuncitem._args)
        else:
            funcargs = pyfuncitem.funcargs
            testfunction(**funcargs)

def pytest_collect_file(path, parent):
    ext = path.ext
    pb = path.purebasename
    if ext == ".py" and (pb.startswith("test_") or pb.endswith("_test") or
       parent.session.isinitpath(path)):
        return parent.ihook.pytest_pycollect_makemodule(
            path=path, parent=parent)

def pytest_pycollect_makemodule(path, parent):
    return Module(path, parent)

def pytest_pycollect_makeitem(__multicall__, collector, name, obj):
    res = __multicall__.execute()
    if res is not None:
        return res
    if collector._istestclasscandidate(name, obj):
        #if hasattr(collector.obj, 'unittest'):
        #    return # we assume it's a mixin class for a TestCase derived one
        return Class(name, parent=collector)
    elif collector.funcnamefilter(name) and hasattr(obj, '__call__'):
        if is_generator(obj):
            return Generator(name, parent=collector)
        else:
            return collector._genfunctions(name, obj)

def is_generator(func):
    try:
        return py.code.getrawcode(func).co_flags & 32 # generator function
    except AttributeError: # builtin functions have no bytecode
        # assume them to not be generators
        return False

class PyobjMixin(object):
    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):
        try:
            return self._fslineno
        except AttributeError:
            pass
        obj = self.obj
        # xxx let decorators etc specify a sane ordering
        if hasattr(obj, 'place_as'):
            obj = obj.place_as

        self._fslineno = py.code.getfslineno(obj)
        return self._fslineno

    def reportinfo(self):
        # XXX caching?
        obj = self.obj
        if hasattr(obj, 'compat_co_firstlineno'):
            # nose compatibility
            fspath = sys.modules[obj.__module__].__file__
            if fspath.endswith(".pyc"):
                fspath = fspath[:-1]
            #assert 0
            #fn = inspect.getsourcefile(obj) or inspect.getfile(obj)
            lineno = obj.compat_co_firstlineno
            modpath = obj.__module__
        else:
            fspath, lineno = self._getfslineno()
            modpath = self.getmodpath()
        return fspath, lineno, modpath

class PyCollectorMixin(PyobjMixin, pytest.Collector):

    def funcnamefilter(self, name):
        return name.startswith('test')
    def classnamefilter(self, name):
        return name.startswith('Test')

    def collect(self):
        # 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 dic.items():
                if name in seen:
                    continue
                seen[name] = True
                if name[0] != "_":
                    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):
        return self.ihook.pytest_pycollect_makeitem(
            collector=self, name=name, obj=obj)

    def _istestclasscandidate(self, name, obj):
        if self.classnamefilter(name) and \
           inspect.isclass(obj):
            if hasinit(obj):
                # XXX WARN
                return False
            return True

    def _genfunctions(self, name, funcobj):
        module = self.getparent(Module).obj
        clscol = self.getparent(Class)
        cls = clscol and clscol.obj or None
        metafunc = Metafunc(funcobj, config=self.config,
            cls=cls, module=module)
        gentesthook = self.config.hook.pytest_generate_tests
        plugins = getplugins(self, withpy=True)
        gentesthook.pcall(plugins, metafunc=metafunc)
        if not metafunc._calls:
            return Function(name, parent=self)
        l = []
        for callspec in metafunc._calls:
            subname = "%s[%s]" %(name, callspec.id)
            function = Function(name=subname, parent=self,
                callspec=callspec, callobj=funcobj, keywords={callspec.id:True})
            l.append(function)
        return l

class Module(pytest.File, PyCollectorMixin):
    def _getobj(self):
        return self._memoizedcall('_obj', self._importtestmodule)

    def _importtestmodule(self):
        # we assume we are only called once per module
        try:
            mod = self.fspath.pyimport(ensuresyspath=True)
        except SyntaxError:
            excinfo = py.code.ExceptionInfo()
            raise self.CollectError(excinfo.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: 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):
        if hasattr(self.obj, 'setup_module'):
            #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 inspect.getargspec(self.obj.setup_module)[0]:
                self.obj.setup_module(self.obj)
            else:
                self.obj.setup_module()

    def teardown(self):
        if hasattr(self.obj, 'teardown_module'):
            #XXX: nose compat hack, move to nose plugin
            # if it takes a positional arg, its probably a py.test style one
            # so we pass the current module object
            if inspect.getargspec(self.obj.teardown_module)[0]:
                self.obj.teardown_module(self.obj)
            else:
                self.obj.teardown_module()

class Class(PyCollectorMixin, pytest.Collector):

    def collect(self):
        return [Instance(name="()", parent=self)]

    def setup(self):
        setup_class = getattr(self.obj, 'setup_class', None)
        if setup_class is not None:
            setup_class = getattr(setup_class, 'im_func', setup_class)
            setup_class(self.obj)

    def teardown(self):
        teardown_class = getattr(self.obj, 'teardown_class', None)
        if teardown_class is not None:
            teardown_class = getattr(teardown_class, 'im_func', teardown_class)
            teardown_class(self.obj)

class Instance(PyCollectorMixin, pytest.Collector):
    def _getobj(self):
        return self.parent.obj()

    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 inspect.ismethod(self.obj):
            name = 'setup_method'
        else:
            name = 'setup_function'
        if isinstance(self.parent, Instance):
            obj = self.parent.newinstance()
            self.obj = self._getobj()
        else:
            obj = self.parent.obj
        setup_func_or_method = getattr(obj, name, None)
        if setup_func_or_method is not None:
            setup_func_or_method(self.obj)

    def teardown(self):
        """ perform teardown for this test function. """
        if inspect.ismethod(self.obj):
            name = 'teardown_method'
        else:
            name = 'teardown_function'
        obj = self.parent.obj
        teardown_func_or_meth = getattr(obj, name, None)
        if teardown_func_or_meth is not None:
            teardown_func_or_meth(self.obj)

    def _prunetraceback(self, excinfo):
        if hasattr(self, '_obj') and not self.config.option.fulltrace:
            code = py.code.Code(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=cutdir)
            excinfo.traceback = ntraceback.filter()

    def _repr_failure_py(self, excinfo, style="long"):
        if excinfo.errisinstance(FuncargRequest.LookupError):
            fspath, lineno, msg = self.reportinfo()
            lines, _ = inspect.getsourcelines(self.obj)
            for i, line in enumerate(lines):
                if line.strip().startswith('def'):
                    return FuncargLookupErrorRepr(fspath, lineno,
            lines[:i+1], str(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"
        return self._repr_failure_py(excinfo,
            style=self.config.option.tbstyle)

class FuncargLookupErrorRepr(TerminalRepr):
    def __init__(self, filename, firstlineno, deflines, errorstring):
        self.deflines = deflines
        self.errorstring = errorstring
        self.filename = filename
        self.firstlineno = firstlineno

    def toterminal(self, tw):
        tw.line()
        for line in self.deflines:
            tw.line("    " + line.strip())
        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 Generator(FunctionMixin, PyCollectorMixin, pytest.Collector):
    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.config._setupstate.prepare(self)

        l = []
        seen = {}
        for i, x in enumerate(self.obj()):
            name, call, args = self.getcallargs(x)
            if not py.builtin.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(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


#
#  Test Items
#
_dummy = object()
class Function(FunctionMixin, pytest.Item):
    """ a Function Item is responsible for setting up
        and executing a Python callable test object.
    """
    _genid = None
    def __init__(self, name, parent=None, args=None, config=None,
                 callspec=None, callobj=_dummy, keywords=None, session=None):
        super(Function, self).__init__(name, parent,
            config=config, session=session)
        self._args = args
        if self._isyieldedfunction():
            assert not callspec, (
                "yielded functions (deprecated) cannot have funcargs")
        else:
            if callspec is not None:
                self.funcargs = callspec.funcargs or {}
                self._genid = callspec.id
                if hasattr(callspec, "param"):
                    self._requestparam = callspec.param
            else:
                self.funcargs = {}
        if callobj is not _dummy:
            self._obj = callobj
        self.function = getattr(self.obj, 'im_func', self.obj)
        self.keywords.update(py.builtin._getfuncdict(self.obj) or {})
        if keywords:
            self.keywords.update(keywords)

    def _getobj(self):
        name = self.name
        i = name.find("[") # parametrization
        if i != -1:
            name = name[:i]
        return getattr(self.parent.obj, name)

    def _isyieldedfunction(self):
        return self._args 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()
        if hasattr(self, 'funcargs'):
            fillfuncargs(self)

    def __eq__(self, other):
        try:
            return (self.name == other.name and
                    self._args == other._args and
                    self.parent == other.parent and
                    self.obj == other.obj and
                    getattr(self, '_genid', None) ==
                    getattr(other, '_genid', None)
            )
        except AttributeError:
            pass
        return False

    def __ne__(self, other):
        return not self == other

    def __hash__(self):
        return hash((self.parent, self.name))

def hasinit(obj):
    init = getattr(obj, '__init__', None)
    if init:
        if init != object.__init__:
            return True


def getfuncargnames(function):
    # XXX merge with main.py's varnames
    argnames = py.std.inspect.getargs(py.code.getrawcode(function))[0]
    startindex = py.std.inspect.ismethod(function) and 1 or 0
    defaults = getattr(function, 'func_defaults',
                       getattr(function, '__defaults__', None)) or ()
    numdefaults = len(defaults)
    if numdefaults:
        return argnames[startindex:-numdefaults]
    return argnames[startindex:]

def fillfuncargs(function):
    """ fill missing funcargs. """
    request = FuncargRequest(pyfuncitem=function)
    request._fillfuncargs()

def getplugins(node, withpy=False): # might by any node
    plugins = node.config._getmatchingplugins(node.fspath)
    if withpy:
        mod = node.getparent(pytest.Module)
        if mod is not None:
            plugins.append(mod.obj)
        inst = node.getparent(pytest.Instance)
        if inst is not None:
            plugins.append(inst.obj)
    return plugins

_notexists = object()
class CallSpec:
    def __init__(self, funcargs, id, param):
        self.funcargs = funcargs
        self.id = id
        if param is not _notexists:
            self.param = param
    def __repr__(self):
        return "<CallSpec id=%r param=%r funcargs=%r>" %(
            self.id, getattr(self, 'param', '?'), self.funcargs)

class Metafunc:
    def __init__(self, function, config=None, cls=None, module=None):
        self.config = config
        self.module = module
        self.function = function
        self.funcargnames = getfuncargnames(function)
        self.cls = cls
        self.module = module
        self._calls = []
        self._ids = py.builtin.set()

[docs] def addcall(self, funcargs=None, id=_notexists, param=_notexists): """ add a new call to the underlying test function during the collection phase of a test run. :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` the length of the currently list of calls to the test function will be used. :arg param: will be exposed to a later funcarg factory invocation through the ``request.param`` attribute. Setting it (instead of directly providing a ``funcargs`` ditionary) is called *indirect parametrization*. Indirect parametrization is preferable if test values are expensive to setup or can only be created after certain fixtures or test-run related initialization code has been run. """ assert funcargs is None or isinstance(funcargs, dict) 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) self._calls.append(CallSpec(funcargs, id, param))
[docs]class FuncargRequest: """ A request for function arguments from a test function. """ _argprefix = "pytest_funcarg__" _argname = None class LookupError(LookupError): """ error on performing funcarg request. """ def __init__(self, pyfuncitem): self._pyfuncitem = pyfuncitem if hasattr(pyfuncitem, '_requestparam'): self.param = pyfuncitem._requestparam self._plugins = getplugins(pyfuncitem, withpy=True) self._funcargs = self._pyfuncitem.funcargs.copy() self._name2factory = {} self._currentarg = None @property
[docs] def function(self): """ function object of the test invocation. """ return self._pyfuncitem.obj
@property
[docs] def keywords(self): """ keywords of the test function item. .. versionadded:: 2.0 """ return self._pyfuncitem.keywords
@property
[docs] def module(self): """ module where the test function was collected. """ return self._pyfuncitem.getparent(pytest.Module).obj
@property
[docs] 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. """ return py.builtin._getimself(self.function) @property
[docs] def config(self): """ the pytest config object associated with this request. """ return self._pyfuncitem.config
@property def fspath(self): """ the file system path of the test module which collected this test. """ return self._pyfuncitem.fspath def _fillfuncargs(self): argnames = getfuncargnames(self.function) if argnames: assert not getattr(self._pyfuncitem, '_args', None), ( "yielded functions cannot have funcargs") for argname in argnames: if argname not in self._pyfuncitem.funcargs: self._pyfuncitem.funcargs[argname] = self.getfuncargvalue(argname)
[docs] 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 ``py.test.mark.NAME(...)``. """ if not isinstance(marker, py.test.mark.XYZ.__class__): raise ValueError("%r is not a py.test.mark.* object") self._pyfuncitem.keywords[marker.markname] = marker
[docs] def cached_setup(self, setup, teardown=None, scope="module", extrakey=None): """ 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. :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._currentarg, self._getscopeitem(scope), extrakey) cache = self.config._setupcache try: val = cache[cachekey] except KeyError: val = setup() cache[cachekey] = val if teardown is not None: def finalizer(): del cache[cachekey] teardown(val) self._addfinalizer(finalizer, scope=scope) return val
[docs] def getfuncargvalue(self, argname): """ Retrieve a function argument by name for this test function invocation. This allows one function argument factory to call another function argument factory. If there are two funcarg factories for the same test function argument the first factory may use ``getfuncargvalue`` to call the second one and do something additional with the resource. """ try: return self._funcargs[argname] except KeyError: pass if argname not in self._name2factory: self._name2factory[argname] = self.config.pluginmanager.listattr( plugins=self._plugins, attrname=self._argprefix + str(argname) ) #else: we are called recursively if not self._name2factory[argname]: self._raiselookupfailed(argname) funcargfactory = self._name2factory[argname].pop() oldarg = self._currentarg self._currentarg = argname try: self._funcargs[argname] = res = funcargfactory(request=self) finally: self._currentarg = oldarg return res
def _getscopeitem(self, scope): if scope == "function": return self._pyfuncitem elif scope == "session": return None elif scope == "class": x = self._pyfuncitem.getparent(pytest.Class) if x is not None: return x scope = "module" if scope == "module": return self._pyfuncitem.getparent(pytest.Module) raise ValueError("unknown finalization scope %r" %(scope,))
[docs] def addfinalizer(self, finalizer): """add finalizer function to be called after test function finished execution. """ self._addfinalizer(finalizer, scope="function")
def _addfinalizer(self, finalizer, scope): colitem = self._getscopeitem(scope) self.config._setupstate.addfinalizer( finalizer=finalizer, colitem=colitem) def __repr__(self): return "<FuncargRequest for %r>" %(self._pyfuncitem) def _raiselookupfailed(self, argname): available = [] for plugin in self._plugins: for name in vars(plugin): if name.startswith(self._argprefix): name = name[len(self._argprefix):] if name not in available: available.append(name) fspath, lineno, msg = self._pyfuncitem.reportinfo() msg = "LookupError: no factory found for function argument %r" % (argname,) msg += "\n available funcargs: %s" %(", ".join(available),) msg += "\n use 'py.test --funcargs [testpath]' for help on them." raise self.LookupError(msg)
def showfuncargs(config): from _pytest.session import Session session = Session(config) session.perform_collect() if session.items: plugins = getplugins(session.items[0]) else: plugins = getplugins(session) curdir = py.path.local() tw = py.io.TerminalWriter() verbose = config.getvalue("verbose") for plugin in plugins: available = [] for name, factory in vars(plugin).items(): if name.startswith(FuncargRequest._argprefix): name = name[len(FuncargRequest._argprefix):] if name not in available: available.append([name, factory]) if available: pluginname = plugin.__name__ for name, factory in available: loc = getlocation(factory, curdir) if verbose: funcargspec = "%s -- %s" %(name, loc,) else: funcargspec = name tw.line(funcargspec, green=True) doc = factory.__doc__ or "" if doc: for line in doc.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(ExpectedException, *args, **kwargs): """ assert that a code block/function call raises an exception. If using Python 2.5 or above, you may use this function as a context manager:: >>> with raises(ZeroDivisionError): ... 1/0 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 which which will be executed:: >>> raises(ZeroDivisionError, "f(0)") <ExceptionInfo ...> """ __tracebackhide__ = True if not args: return RaisesContext(ExpectedException) 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 = py.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 ExpectedException: return py.code.ExceptionInfo() else: func = args[0] try: func(*args[1:], **kwargs) except ExpectedException: return py.code.ExceptionInfo() k = ", ".join(["%s=%r" % x for x in kwargs.items()]) if k: k = ', ' + k expr = '%s(%r%s)' %(getattr(func, '__name__', func), args, k) pytest.fail("DID NOT RAISE") class RaisesContext(object): def __init__(self, ExpectedException): self.ExpectedException = ExpectedException self.excinfo = None def __enter__(self): self.excinfo = object.__new__(py.code.ExceptionInfo) return self.excinfo def __exit__(self, *tp): __tracebackhide__ = True if tp[0] is None: pytest.fail("DID NOT RAISE") self.excinfo.__init__(tp) return issubclass(self.excinfo.type, self.ExpectedException)