import functools
import inspect
import itertools
import sys
import warnings
from collections import defaultdict
from collections import deque
from typing import Dict
from typing import List
from typing import Optional
from typing import Tuple
import attr
import py.path
import _pytest
from _pytest._code.code import FormattedExcinfo
from _pytest._code.code import TerminalRepr
from _pytest._code.source import getfslineno
from _pytest.compat import _format_args
from _pytest.compat import _PytestWrapper
from _pytest.compat import get_real_func
from _pytest.compat import get_real_method
from _pytest.compat import getfuncargnames
from _pytest.compat import getimfunc
from _pytest.compat import getlocation
from _pytest.compat import is_generator
from _pytest.compat import NOTSET
from _pytest.compat import order_preserving_dict
from _pytest.compat import safe_getattr
from _pytest.compat import TYPE_CHECKING
from _pytest.deprecated import FIXTURE_POSITIONAL_ARGUMENTS
from _pytest.deprecated import FUNCARGNAMES
from _pytest.mark import ParameterSet
from _pytest.outcomes import fail
from _pytest.outcomes import TEST_OUTCOME
if TYPE_CHECKING:
from typing import Type
from typing_extensions import Literal
from _pytest import nodes
from _pytest._io import TerminalWriter
from _pytest.main import Session
from _pytest.runner import _RuntestPhase
_Scope = Literal["session", "package", "module", "class", "function"]
@attr.s(frozen=True)
class PseudoFixtureDef:
cached_result = attr.ib()
scope = attr.ib()
def pytest_sessionstart(session: "Session"):
import _pytest.python
import _pytest.nodes
scopename2class.update(
{
"package": _pytest.python.Package,
"class": _pytest.python.Class,
"module": _pytest.python.Module,
"function": _pytest.nodes.Item,
"session": _pytest.main.Session,
}
)
session._fixturemanager = FixtureManager(session)
scopename2class = {} # type: Dict[str, Type[nodes.Node]]
scope2props = dict(session=()) # type: Dict[str, Tuple[str, ...]]
scope2props["package"] = ("fspath",)
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(
"{} not available in {}-scoped context".format(scopename, self.scope)
)
return property(provide, None, None, func.__doc__)
return decoratescope
def get_scope_package(node, fixturedef):
import pytest
cls = pytest.Package
current = node
fixture_package_name = "{}/{}".format(fixturedef.baseid, "__init__.py")
while current and (
type(current) is not cls or fixture_package_name != current.nodeid
):
current = current.parent
if current is None:
return node.session
return current
def get_scope_node(node, scope):
cls = scopename2class.get(scope)
if cls is None:
raise ValueError("unknown scope")
return node.getparent(cls)
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, _pytest.python.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 getfixturemarker(obj):
""" return fixturemarker or None if it doesn't exist or raised
exceptions."""
try:
return getattr(obj, "_pytestfixturefunction", None)
except TEST_OUTCOME:
# some objects raise errors like request (from flask import request)
# we don't expect them to be fixture functions
return 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.indices.items() is random order of argnames. Need to
# sort this so that different calls to
# get_parametrized_fixture_keys will be deterministic.
for argname, param_index in sorted(cs.indices.items()):
if cs._arg2scopenum[argname] != scopenum:
continue
if scopenum == 0: # session
key = (argname, param_index)
elif scopenum == 1: # package
key = (argname, param_index, item.fspath.dirpath())
elif scopenum == 2: # module
key = (argname, param_index, item.fspath)
elif scopenum == 3: # class
key = (argname, param_index, item.fspath, item.cls)
yield key
# 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 = {}
items_by_argkey = {}
for scopenum in range(0, scopenum_function):
argkeys_cache[scopenum] = d = {}
items_by_argkey[scopenum] = item_d = defaultdict(deque)
for item in items:
keys = order_preserving_dict.fromkeys(
get_parametrized_fixture_keys(item, scopenum)
)
if keys:
d[item] = keys
for key in keys:
item_d[key].append(item)
items = order_preserving_dict.fromkeys(items)
return list(reorder_items_atscope(items, argkeys_cache, items_by_argkey, 0))
def fix_cache_order(item, argkeys_cache, items_by_argkey):
for scopenum in range(0, scopenum_function):
for key in argkeys_cache[scopenum].get(item, []):
items_by_argkey[scopenum][key].appendleft(item)
def reorder_items_atscope(items, argkeys_cache, items_by_argkey, scopenum):
if scopenum >= scopenum_function or len(items) < 3:
return items
ignore = set()
items_deque = deque(items)
items_done = order_preserving_dict()
scoped_items_by_argkey = items_by_argkey[scopenum]
scoped_argkeys_cache = argkeys_cache[scopenum]
while items_deque:
no_argkey_group = order_preserving_dict()
slicing_argkey = None
while items_deque:
item = items_deque.popleft()
if item in items_done or item in no_argkey_group:
continue
argkeys = order_preserving_dict.fromkeys(
k for k in scoped_argkeys_cache.get(item, []) if k not in ignore
)
if not argkeys:
no_argkey_group[item] = None
else:
slicing_argkey, _ = argkeys.popitem()
# we don't have to remove relevant items from later in the deque because they'll just be ignored
matching_items = [
i for i in scoped_items_by_argkey[slicing_argkey] if i in items
]
for i in reversed(matching_items):
fix_cache_order(i, argkeys_cache, items_by_argkey)
items_deque.appendleft(i)
break
if no_argkey_group:
no_argkey_group = reorder_items_atscope(
no_argkey_group, argkeys_cache, items_by_argkey, scopenum + 1
)
for item in no_argkey_group:
items_done[item] = None
ignore.add(slicing_argkey)
return items_done
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()
def get_direct_param_fixture_func(request):
return request.param
@attr.s(slots=True)
class FuncFixtureInfo:
# original function argument names
argnames = attr.ib(type=tuple)
# argnames that function immediately requires. These include argnames +
# fixture names specified via usefixtures and via autouse=True in fixture
# definitions.
initialnames = attr.ib(type=tuple)
names_closure = attr.ib() # type: List[str]
name2fixturedefs = attr.ib() # type: Dict[str, List[FixtureDef]]
def prune_dependency_tree(self):
"""Recompute names_closure from initialnames and name2fixturedefs
Can only reduce names_closure, which means that the new closure will
always be a subset of the old one. The order is preserved.
This method is needed because direct parametrization may shadow some
of the fixtures that were included in the originally built dependency
tree. In this way the dependency tree can get pruned, and the closure
of argnames may get reduced.
"""
closure = set()
working_set = set(self.initialnames)
while working_set:
argname = working_set.pop()
# argname may be smth not included in the original names_closure,
# in which case we ignore it. This currently happens with pseudo
# FixtureDefs which wrap 'get_direct_param_fixture_func(request)'.
# So they introduce the new dependency 'request' which might have
# been missing in the original tree (closure).
if argname not in closure and argname in self.names_closure:
closure.add(argname)
if argname in self.name2fixturedefs:
working_set.update(self.name2fixturedefs[argname][-1].argnames)
self.names_closure[:] = sorted(closure, key=self.names_closure.index)
[docs]class FixtureRequest:
""" 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._fixture_defs = {} # type: Dict[str, FixtureDef]
fixtureinfo = pyfuncitem._fixtureinfo
self._arg2fixturedefs = fixtureinfo.name2fixturedefs.copy()
self._arg2index = {}
self._fixturemanager = pyfuncitem.session._fixturemanager
self._phase = None # type: Optional[_RuntestPhase]
@property
def fixturenames(self):
"""names of all active fixtures in this request"""
result = list(self._pyfuncitem._fixtureinfo.names_closure)
result.extend(set(self._fixture_defs).difference(result))
return result
@property
def funcargnames(self):
""" alias attribute for ``fixturenames`` for pre-2.3 compatibility"""
warnings.warn(FUNCARGNAMES, stacklevel=2)
return self.fixturenames
@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 dynamic call to
# getfixturevalue(argname) usage which was naturally
# not known at parsing/collection time
parentid = self._pyfuncitem.parent.nodeid
fixturedefs = self._fixturemanager.getfixturedefs(argname, parentid)
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.python.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)
return getattr(function, "__self__", None)
@scopeproperty()
def module(self):
""" python module object where the test function was collected. """
return self._pyfuncitem.getparent(_pytest.python.Module).obj
@scopeproperty()
def fspath(self) -> py.path.local:
""" the file system path of the test module which collected this test. """
return self._pyfuncitem.fspath # type: ignore[no-any-return]
@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
[docs] 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
)
[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 ``pytest.mark.NAME(...)``.
"""
self.node.add_marker(marker)
[docs] 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.getfixturevalue(argname)
[docs] def getfixturevalue(self, argname):
""" Dynamically run a named fixture function.
Declaring fixtures via function argument is recommended where possible.
But if you can only decide whether to use another fixture at test
setup time, you may use this function to retrieve it inside a fixture
or test function body.
"""
return self._get_active_fixturedef(argname).cached_result[0]
def _get_active_fixturedef(self, argname):
try:
return self._fixture_defs[argname]
except KeyError:
try:
fixturedef = self._getnextfixturedef(argname)
except FixtureLookupError:
if argname == "request":
cached_result = (self, [0], None)
scope = "function"
return PseudoFixtureDef(cached_result, scope)
raise
# remove indent to prevent the python3 exception
# from leaking into the call
self._compute_fixture_value(fixturedef)
self._fixture_defs[argname] = fixturedef
return fixturedef
def _get_fixturestack(self):
current = self
values = []
while 1:
fixturedef = getattr(current, "_fixturedef", None)
if fixturedef is None:
values.reverse()
return values
values.append(fixturedef)
current = current._parent_request
def _compute_fixture_value(self, fixturedef: "FixtureDef") -> None:
"""
Creates a SubRequest based on "self" and calls the execute method of the given fixturedef object. This will
force the FixtureDef object to throw away any previous results and compute a new fixture value, which
will be stored into the FixtureDef object itself.
"""
# 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
has_params = fixturedef.params is not None
fixtures_not_supported = getattr(funcitem, "nofuncargs", False)
if has_params and fixtures_not_supported:
msg = (
"{name} does not support fixtures, maybe unittest.TestCase subclass?\n"
"Node id: {nodeid}\n"
"Function type: {typename}"
).format(
name=funcitem.name,
nodeid=funcitem.nodeid,
typename=type(funcitem).__name__,
)
fail(msg, pytrace=False)
if has_params:
frame = inspect.stack()[3]
frameinfo = inspect.getframeinfo(frame[0])
source_path = py.path.local(frameinfo.filename)
source_lineno = frameinfo.lineno
rel_source_path = source_path.relto(funcitem.config.rootdir)
if rel_source_path:
source_path_str = rel_source_path
else:
source_path_str = str(source_path)
msg = (
"The requested fixture has no parameter defined for test:\n"
" {}\n\n"
"Requested fixture '{}' defined in:\n{}"
"\n\nRequested here:\n{}:{}".format(
funcitem.nodeid,
fixturedef.argname,
getlocation(fixturedef.func, funcitem.config.rootdir),
source_path_str,
source_lineno,
)
)
fail(msg, pytrace=False)
else:
param_index = funcitem.callspec.indices[argname]
# 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)
try:
# call the fixture function
fixturedef.execute(request=subrequest)
finally:
self._schedule_finalizers(fixturedef, subrequest)
def _schedule_finalizers(self, fixturedef, subrequest):
# if fixture function failed it might have registered finalizers
self.session._setupstate.addfinalizer(
functools.partial(fixturedef.finish, request=subrequest), subrequest.node
)
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()
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 + 1, 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
if scope == "package":
node = get_scope_package(self._pyfuncitem, self._fixturedef)
else:
node = get_scope_node(self._pyfuncitem, scope)
if node is None and scope == "class":
# fallback to function item itself
node = self._pyfuncitem
assert node, 'Could not obtain a node for scope "{}" for function {!r}'.format(
scope, self._pyfuncitem
)
return node
def __repr__(self):
return "<FixtureRequest for {!r} _phase={}>".format(self.node, self._phase)
class SubRequest(FixtureRequest):
""" a sub request for handling getting a fixture from a
test function/fixture. """
def __init__(
self,
request: "FixtureRequest",
scope: "_Scope",
param,
param_index: int,
fixturedef: "FixtureDef",
) -> None:
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._pyfuncitem = request._pyfuncitem
self._fixture_defs = request._fixture_defs
self._arg2fixturedefs = request._arg2fixturedefs
self._arg2index = request._arg2index
self._fixturemanager = request._fixturemanager
def __repr__(self):
return "<SubRequest {!r} for {!r} _phase={}>".format(
self.fixturename, self._pyfuncitem, self._phase
)
@property
def _phase(self) -> "Optional[_RuntestPhase]": # type: ignore[override]
return self._parent_request._phase
def addfinalizer(self, finalizer):
self._fixturedef.addfinalizer(finalizer)
def _schedule_finalizers(self, fixturedef, subrequest):
# if the executing fixturedef was not explicitly requested in the argument list (via
# getfixturevalue inside the fixture call) then ensure this fixture def will be finished
# first
if fixturedef.argname not in self.fixturenames:
fixturedef.addfinalizer(
functools.partial(self._fixturedef.finish, request=self)
)
super()._schedule_finalizers(fixturedef, subrequest)
scopes = "session package module class function".split()
scopenum_function = scopes.index("function")
def scopemismatch(currentscope, newscope):
return scopes.index(newscope) > scopes.index(currentscope)
def scope2index(scope, descr, where=None):
"""Look up the index of ``scope`` and raise a descriptive value error
if not defined.
"""
try:
return scopes.index(scope)
except ValueError:
fail(
"{} {}got an unexpected scope value '{}'".format(
descr, "from {} ".format(where) if where else "", scope
),
pytrace=False,
)
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) -> "FixtureLookupErrorRepr":
tblines = [] # type: List[str]
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 (OSError, IndexError, TypeError):
error_msg = "file %s, line %s: source code not available"
addline(error_msg % (fspath, lineno + 1))
else:
addline("file {}, line {}".format(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 = set()
parentid = self.request._pyfuncitem.parent.nodeid
for name, fixturedefs in fm._arg2fixturedefs.items():
faclist = list(fm._matchfactories(fixturedefs, parentid))
if faclist:
available.add(name)
if self.argname in available:
msg = " recursive dependency involving fixture '{}' detected".format(
self.argname
)
else:
msg = "fixture '{}' not found".format(self.argname)
msg += "\n available fixtures: {}".format(", ".join(sorted(available)))
msg += "\n use 'pytest --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: "TerminalWriter") -> None:
# tw.line("FixtureLookupError: %s" %(self.argname), red=True)
for tbline in self.tblines:
tw.line(tbline.rstrip())
lines = self.errorstring.split("\n")
if lines:
tw.line(
"{} {}".format(FormattedExcinfo.fail_marker, lines[0].strip()),
red=True,
)
for line in lines[1:]:
tw.line(
"{} {}".format(FormattedExcinfo.flow_marker, line.strip()),
red=True,
)
tw.line()
tw.line("%s:%d" % (self.filename, self.firstlineno + 1))
def fail_fixturefunc(fixturefunc, msg):
fs, lineno = getfslineno(fixturefunc)
location = "{}:{}".format(fs, lineno + 1)
source = _pytest._code.Source(fixturefunc)
fail(msg + ":\n\n" + str(source.indent()) + "\n" + location, pytrace=False)
def call_fixture_func(fixturefunc, request, kwargs):
yieldctx = is_generator(fixturefunc)
if yieldctx:
it = fixturefunc(**kwargs)
res = next(it)
finalizer = functools.partial(_teardown_yield_fixture, fixturefunc, it)
request.addfinalizer(finalizer)
else:
res = fixturefunc(**kwargs)
return res
def _teardown_yield_fixture(fixturefunc, it):
"""Executes the teardown of a fixture function by advancing the iterator after the
yield and ensure the iteration ends (if not it means there is more than one yield in the function)"""
try:
next(it)
except StopIteration:
pass
else:
fail_fixturefunc(
fixturefunc, "yield_fixture function has more than one 'yield'"
)
def _eval_scope_callable(scope_callable, fixture_name, config):
try:
result = scope_callable(fixture_name=fixture_name, config=config)
except Exception:
raise TypeError(
"Error evaluating {} while defining fixture '{}'.\n"
"Expected a function with the signature (*, fixture_name, config)".format(
scope_callable, fixture_name
)
)
if not isinstance(result, str):
fail(
"Expected {} to return a 'str' while defining fixture '{}', but it returned:\n"
"{!r}".format(scope_callable, fixture_name, result),
pytrace=False,
)
return result
[docs]class FixtureDef:
""" A container for a factory definition. """
def __init__(
self,
fixturemanager,
baseid,
argname,
func,
scope,
params,
unittest=False,
ids=None,
):
self._fixturemanager = fixturemanager
self.baseid = baseid or ""
self.has_location = baseid is not None
self.func = func
self.argname = argname
if callable(scope):
scope = _eval_scope_callable(scope, argname, fixturemanager.config)
self.scope = scope
self.scopenum = scope2index(
scope or "function",
descr="Fixture '{}'".format(func.__name__),
where=baseid,
)
self.params = params
self.argnames = getfuncargnames(func, name=argname, is_method=unittest)
self.unittest = unittest
self.ids = ids
self.cached_result = None
self._finalizers = []
def addfinalizer(self, finalizer):
self._finalizers.append(finalizer)
def finish(self, request):
exc = None
try:
while self._finalizers:
try:
func = self._finalizers.pop()
func()
except BaseException as e:
# XXX Only first exception will be seen by user,
# ideally all should be reported.
if exc is None:
exc = e
if exc:
raise exc
finally:
hook = self._fixturemanager.session.gethookproxy(request.node.fspath)
hook.pytest_fixture_post_finalizer(fixturedef=self, request=request)
# even if finalization fails, we invalidate
# the cached fixture value and remove
# all finalizers because they may be bound methods which will
# keep instances alive
self.cached_result = None
self._finalizers = []
def execute(self, request):
# get required arguments and register our own finish()
# with their finalization
for argname in self.argnames:
fixturedef = request._get_active_fixturedef(argname)
if argname != "request":
fixturedef.addfinalizer(functools.partial(self.finish, request=request))
my_cache_key = self.cache_key(request)
if self.cached_result is not None:
result, cache_key, err = self.cached_result
# note: comparison with `==` can fail (or be expensive) for e.g.
# numpy arrays (#6497)
if my_cache_key is cache_key:
if err is not None:
_, val, tb = err
raise val.with_traceback(tb)
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(request)
assert self.cached_result is None
hook = self._fixturemanager.session.gethookproxy(request.node.fspath)
return hook.pytest_fixture_setup(fixturedef=self, request=request)
def cache_key(self, request):
return request.param_index if not hasattr(request, "param") else request.param
def __repr__(self):
return "<FixtureDef argname={!r} scope={!r} baseid={!r}>".format(
self.argname, self.scope, self.baseid
)
def resolve_fixture_function(fixturedef, request):
"""Gets the actual callable that can be called to obtain the fixture value, dealing with unittest-specific
instances and bound methods.
"""
fixturefunc = fixturedef.func
if fixturedef.unittest:
if request.instance is not None:
# bind the unbound method to the TestCase instance
fixturefunc = fixturedef.func.__get__(request.instance)
else:
# the fixture function needs to be bound to the actual
# request.instance so that code working with "fixturedef" behaves
# as expected.
if request.instance is not None:
# handle the case where fixture is defined not in a test class, but some other class
# (for example a plugin class with a fixture), see #2270
if hasattr(fixturefunc, "__self__") and not isinstance(
request.instance, fixturefunc.__self__.__class__
):
return fixturefunc
fixturefunc = getimfunc(fixturedef.func)
if fixturefunc != fixturedef.func:
fixturefunc = fixturefunc.__get__(request.instance)
return fixturefunc
def pytest_fixture_setup(fixturedef, request):
""" Execution of fixture setup. """
kwargs = {}
for argname in fixturedef.argnames:
fixdef = request._get_active_fixturedef(argname)
assert fixdef.cached_result is not None
result, arg_cache_key, exc = fixdef.cached_result
request._check_scope(argname, request.scope, fixdef.scope)
kwargs[argname] = result
fixturefunc = resolve_fixture_function(fixturedef, request)
my_cache_key = fixturedef.cache_key(request)
try:
result = call_fixture_func(fixturefunc, request, kwargs)
except TEST_OUTCOME:
fixturedef.cached_result = (None, my_cache_key, sys.exc_info())
raise
fixturedef.cached_result = (result, my_cache_key, None)
return result
def _ensure_immutable_ids(ids):
if ids is None:
return
if callable(ids):
return ids
return tuple(ids)
def wrap_function_to_error_out_if_called_directly(function, fixture_marker):
"""Wrap the given fixture function so we can raise an error about it being called directly,
instead of used as an argument in a test function.
"""
message = (
'Fixture "{name}" called directly. Fixtures are not meant to be called directly,\n'
"but are created automatically when test functions request them as parameters.\n"
"See https://docs.pytest.org/en/latest/fixture.html for more information about fixtures, and\n"
"https://docs.pytest.org/en/latest/deprecations.html#calling-fixtures-directly about how to update your code."
).format(name=fixture_marker.name or function.__name__)
@functools.wraps(function)
def result(*args, **kwargs):
fail(message, pytrace=False)
# keep reference to the original function in our own custom attribute so we don't unwrap
# further than this point and lose useful wrappings like @mock.patch (#3774)
result.__pytest_wrapped__ = _PytestWrapper(function)
return result
@attr.s(frozen=True)
class FixtureFunctionMarker:
scope = attr.ib()
params = attr.ib(
type=Optional[Tuple[object, ...]],
converter=attr.converters.optional(tuple),
)
autouse = attr.ib(default=False)
# Ignore type because of https://github.com/python/mypy/issues/6172.
ids = attr.ib(default=None, converter=_ensure_immutable_ids) # type: ignore
name = attr.ib(default=None)
def __call__(self, function):
if inspect.isclass(function):
raise ValueError("class fixtures not supported (maybe in the future)")
if getattr(function, "_pytestfixturefunction", False):
raise ValueError(
"fixture is being applied more than once to the same function"
)
function = wrap_function_to_error_out_if_called_directly(function, self)
name = self.name or function.__name__
if name == "request":
location = getlocation(function)
fail(
"'request' is a reserved word for fixtures, use another name:\n {}".format(
location
),
pytrace=False,
)
function._pytestfixturefunction = self
return function
FIXTURE_ARGS_ORDER = ("scope", "params", "autouse", "ids", "name")
def _parse_fixture_args(callable_or_scope, *args, **kwargs):
arguments = {
"scope": "function",
"params": None,
"autouse": False,
"ids": None,
"name": None,
}
kwargs = {
key: value for key, value in kwargs.items() if arguments.get(key) != value
}
fixture_function = None
if isinstance(callable_or_scope, str):
args = list(args)
args.insert(0, callable_or_scope)
else:
fixture_function = callable_or_scope
positionals = set()
for positional, argument_name in zip(args, FIXTURE_ARGS_ORDER):
arguments[argument_name] = positional
positionals.add(argument_name)
duplicated_kwargs = {kwarg for kwarg in kwargs.keys() if kwarg in positionals}
if duplicated_kwargs:
raise TypeError(
"The fixture arguments are defined as positional and keyword: {}. "
"Use only keyword arguments.".format(", ".join(duplicated_kwargs))
)
if positionals:
warnings.warn(FIXTURE_POSITIONAL_ARGUMENTS, stacklevel=2)
arguments.update(kwargs)
return fixture_function, arguments
[docs]def fixture(
callable_or_scope=None,
*args,
scope="function",
params=None,
autouse=False,
ids=None,
name=None
):
"""Decorator to mark a fixture factory function.
This decorator can be used, with 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.
Fixtures can provide their values to test functions using ``return`` or ``yield``
statements. When using ``yield`` the code block after the ``yield`` statement is executed
as teardown code regardless of the test outcome, and must yield exactly once.
:arg scope: the scope for which this fixture is shared, one of
``"function"`` (default), ``"class"``, ``"module"``,
``"package"`` or ``"session"`` (``"package"`` is considered **experimental**
at this time).
This parameter may also be a callable which receives ``(fixture_name, config)``
as parameters, and must return a ``str`` with one of the values mentioned above.
See :ref:`dynamic scope` in the docs for more information.
:arg params: an optional list of parameters which will cause multiple
invocations of the fixture function and all of the tests
using it.
The current parameter is available in ``request.param``.
: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.
:arg name: the name of the fixture. This defaults to the name of the
decorated function. If a fixture is used in the same module in
which it is defined, the function name of the fixture will be
shadowed by the function arg that requests the fixture; one way
to resolve this is to name the decorated function
``fixture_<fixturename>`` and then use
``@pytest.fixture(name='<fixturename>')``.
"""
if params is not None:
params = list(params)
fixture_function, arguments = _parse_fixture_args(
callable_or_scope,
*args,
scope=scope,
params=params,
autouse=autouse,
ids=ids,
name=name,
)
scope = arguments.get("scope")
params = arguments.get("params")
autouse = arguments.get("autouse")
ids = arguments.get("ids")
name = arguments.get("name")
if fixture_function and params is None and autouse is False:
# direct decoration
return FixtureFunctionMarker(scope, params, autouse, name=name)(
fixture_function
)
return FixtureFunctionMarker(scope, params, autouse, ids=ids, name=name)
def yield_fixture(
callable_or_scope=None,
*args,
scope="function",
params=None,
autouse=False,
ids=None,
name=None
):
""" (return a) decorator to mark a yield-fixture factory function.
.. deprecated:: 3.0
Use :py:func:`pytest.fixture` directly instead.
"""
return fixture(
callable_or_scope,
*args,
scope=scope,
params=params,
autouse=autouse,
ids=ids,
name=name,
)
defaultfuncargprefixmarker = fixture()
[docs]@fixture(scope="session")
def pytestconfig(request):
"""Session-scoped fixture that returns the :class:`_pytest.config.Config` object.
Example::
def test_foo(pytestconfig):
if pytestconfig.getoption("verbose") > 0:
...
"""
return request.config
def pytest_addoption(parser):
parser.addini(
"usefixtures",
type="args",
default=[],
help="list of default fixtures to be used with this project",
)
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.
"""
FixtureLookupError = FixtureLookupError
FixtureLookupErrorRepr = FixtureLookupErrorRepr
def __init__(self, session):
self.session = session
self.config = session.config
self._arg2fixturedefs = {}
self._holderobjseen = set()
self._nodeid_and_autousenames = [("", self.config.getini("usefixtures"))]
session.config.pluginmanager.register(self, "funcmanage")
def _get_direct_parametrize_args(self, node):
"""This function returns all the direct parametrization
arguments of a node, so we don't mistake them for fixtures
Check https://github.com/pytest-dev/pytest/issues/5036
This things are done later as well when dealing with parametrization
so this could be improved
"""
parametrize_argnames = []
for marker in node.iter_markers(name="parametrize"):
if not marker.kwargs.get("indirect", False):
try:
p_argnames, _ = ParameterSet._parse_parametrize_args(
*marker.args, **marker.kwargs
)
except TypeError:
pass
else:
parametrize_argnames.extend(p_argnames)
return parametrize_argnames
def getfixtureinfo(self, node, func, cls, funcargs=True):
if funcargs and not getattr(node, "nofuncargs", False):
argnames = getfuncargnames(func, name=node.name, cls=cls)
else:
argnames = ()
usefixtures = itertools.chain.from_iterable(
mark.args for mark in node.iter_markers(name="usefixtures")
)
initialnames = tuple(usefixtures) + argnames
fm = node.session._fixturemanager
initialnames, names_closure, arg2fixturedefs = fm.getfixtureclosure(
initialnames, node, ignore_args=self._get_direct_parametrize_args(node)
)
return FuncFixtureInfo(argnames, initialnames, names_closure, arg2fixturedefs)
def pytest_plugin_registered(self, plugin):
nodeid = None
try:
p = py.path.local(plugin.__file__).realpath()
except AttributeError:
pass
else:
from _pytest import nodes
# 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 != nodes.SEP:
nodeid = nodeid.replace(p.sep, nodes.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)
return autousenames
def getfixtureclosure(self, fixturenames, parentnode, ignore_args=()):
# 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 an 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)
# at this point, fixturenames_closure contains what we call "initialnames",
# which is a set of fixturenames the function immediately requests. We
# need to return it as well, so save this.
initialnames = tuple(fixturenames_closure)
arg2fixturedefs = {}
lastlen = -1
while lastlen != len(fixturenames_closure):
lastlen = len(fixturenames_closure)
for argname in fixturenames_closure:
if argname in ignore_args:
continue
if argname in arg2fixturedefs:
continue
fixturedefs = self.getfixturedefs(argname, parentid)
if fixturedefs:
arg2fixturedefs[argname] = fixturedefs
merge(fixturedefs[-1].argnames)
def sort_by_scope(arg_name):
try:
fixturedefs = arg2fixturedefs[arg_name]
except KeyError:
return scopes.index("function")
else:
return fixturedefs[-1].scopenum
fixturenames_closure.sort(key=sort_by_scope)
return initialnames, 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:
markers = list(metafunc.definition.iter_markers("parametrize"))
for parametrize_mark in markers:
if "argnames" in parametrize_mark.kwargs:
argnames = parametrize_mark.kwargs["argnames"]
else:
argnames = parametrize_mark.args[0]
if not isinstance(argnames, (tuple, list)):
argnames = [
x.strip() for x in argnames.split(",") if x.strip()
]
if argname in argnames:
break
else:
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):
# The attribute can be an arbitrary descriptor, so the attribute
# access below can raise. safe_getatt() ignores such exceptions.
obj = safe_getattr(holderobj, name, None)
marker = getfixturemarker(obj)
if not isinstance(marker, FixtureFunctionMarker):
# magic globals with __getattr__ might have got us a wrong
# fixture attribute
continue
if marker.name:
name = marker.name
# during fixture definition we wrap the original fixture function
# to issue a warning if called directly, so here we unwrap it in order to not emit the warning
# when pytest itself calls the fixture function
obj = get_real_method(obj, holderobj)
fixture_def = FixtureDef(
self,
nodeid,
name,
obj,
marker.scope,
marker.params,
unittest=unittest,
ids=marker.ids,
)
faclist = self._arg2fixturedefs.setdefault(name, [])
if fixture_def.has_location:
faclist.append(fixture_def)
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, fixture_def)
if marker.autouse:
autousenames.append(name)
if autousenames:
self._nodeid_and_autousenames.append((nodeid or "", autousenames))
def getfixturedefs(self, argname, nodeid):
"""
Gets a list of fixtures which are applicable to the given node id.
:param str argname: name of the fixture to search for
:param str nodeid: full node id of the requesting test.
:return: list[FixtureDef]
"""
try:
fixturedefs = self._arg2fixturedefs[argname]
except KeyError:
return None
return tuple(self._matchfactories(fixturedefs, nodeid))
def _matchfactories(self, fixturedefs, nodeid):
from _pytest import nodes
for fixturedef in fixturedefs:
if nodes.ischildnode(fixturedef.baseid, nodeid):
yield fixturedef
