Source code for nose2.tools.such

import logging
import sys
import unittest
from contextlib import contextmanager

from nose2 import util
from nose2.main import PluggableTestProgram

log = logging.getLogger(__name__)

__unittest = True

LAYERS_PLUGIN_NOT_LOADED_MESSAGE = (
    "Warning: Such will not function properly if "
    'the "nose2.plugins.layers" plugin not loaded!\n'
)


[docs] @contextmanager def A(description): """Test scenario context manager. Returns a :class:`nose2.tools.such.Scenario` instance, which by convention is bound to ``it``: .. code-block :: python with such.A('test scenario') as it: # tests and fixtures """ yield Scenario(description)
class Helper(unittest.TestCase): def runTest(self): pass helper = Helper()
[docs] class Scenario: """A test scenario. A test scenario defines a set of fixtures and tests that depend on those fixtures. """ _helper = helper def __init__(self, description): self._group = Group("A %s" % description, 0)
[docs] @contextmanager def having(self, description): """Define a new group under the current group. Fixtures and tests defined within the block will belong to the new group. .. code-block :: python with it.having('a description of this group'): # ... """ last = self._group self._group = self._group.child("having %s" % description) log.debug("starting new group from %s", description) yield self log.debug("leaving group %s", description) self._group = last
def uses(self, layer): log.debug("Adding %s as mixin to %s", layer, self._group) self._group.mixins.append(layer)
[docs] def has_setup(self, func): """Add a :func:`setup` method to this group. The :func:`setup` method will run once, before any of the tests in the containing group. A group may define any number of :func:`setup` functions. They will execute in the order in which they are defined. .. code-block :: python @it.has_setup def setup(): # ... """ self._group.addSetup(func) return func
[docs] def has_teardown(self, func): """Add a :func:`teardown` method to this group. The :func:`teardown` method will run once, after all of the tests in the containing group. A group may define any number of :func:`teardown` functions. They will execute in the order in which they are defined. .. code-block :: python @it.has_teardown def teardown(): # ... """ self._group.addTeardown(func) return func
[docs] def has_test_setup(self, func): """Add a test case :func:`setup` method to this group. The :func:`setup` method will run before each of the tests in the containing group. A group may define any number of test case :func:`setup` functions. They will execute in the order in which they are defined. Test :func:`setup` functions may optionally take one argument. If they do, they will be passed the :class:`unittest.TestCase` instance generated for the test. .. code-block :: python @it.has_test_setup def setup(case): # ... """ self._group.addTestSetUp(func)
[docs] def has_test_teardown(self, func): """Add a test case :func:`teardown` method to this group. The :func:`teardown` method will run before each of the tests in the containing group. A group may define any number of test case :func:`teardown` functions. They will execute in the order in which they are defined. Test :func:`teardown` functions may optionally take one argument. If they do, they will be passed the :class:`unittest.TestCase` instance generated for the test. .. code-block :: python @it.has_test_teardown def teardown(case): # ... """ self._group.addTestTearDown(func)
[docs] def should(self, desc): """Define a test case. Each function marked with this decorator becomes a test case in the current group. The decorator takes one optional argument, the description of the test case: what it **should** do. If this argument is not provided, the docstring of the decorated function will be used as the test case description. Test functions may optionally take one argument. If they do, they will be passed the :class:`unittest.TestCase` instance generated for the test. They can use this TestCase instance to execute assert methods, among other things. .. code-block :: python @it.should('do this') def dothis(case): # .... @it.should def dothat(): "do that also" # .... """ def decorator(f): _desc = desc if isinstance(desc, str) else f.__doc__ case = Case(self._group, f, "should %s" % _desc) self._group.addCase(case) return case if isinstance(desc, type(decorator)): return decorator(desc) return decorator
def __getattr__(self, attr): return getattr(self._helper, attr)
[docs] def createTests(self, mod): """Generate test cases for this scenario. .. warning :: You must call this, passing in :func:`globals`, to generate tests from the scenario. If you don't, **no tests will be created**. .. code-block :: python it.createTests(globals()) """ self._checkForLayersPlugin() self._makeGroupTest(mod, self._group)
def _checkForLayersPlugin(self): currentSession = PluggableTestProgram.getCurrentSession() if not currentSession: return if not currentSession.isPluginLoaded("nose2.plugins.layers"): sys.stderr.write(LAYERS_PLUGIN_NOT_LOADED_MESSAGE) def _makeGroupTest(self, mod, group, parent_layer=None, position=0): layer = self._makeLayer(group, parent_layer, position) case = self._makeTestCase(group, layer, parent_layer) log.debug("Made test case %s with layer %s from %s", case, layer, group) mod[layer.__name__] = layer layer.__module__ = mod["__name__"] name = case.__name__ long_name = " ".join([n[0].description for n in util.ancestry(layer)] + [name]) mod[long_name] = case if name not in mod: mod[name] = case case.__module__ = mod["__name__"] for index, child in enumerate(group._children): self._makeGroupTest(mod, child, layer, index) def _makeTestCase(self, group, layer, parent_layer): attr = {"layer": layer, "group": group, "description": group.description} def _make_test_func(case): """ Needs to be outside of the for-loop scope, so that ``case`` is properly registered as a closure. """ def _test(s, *args): case(s, *args) return _test for index, case in enumerate(group._cases): name = "test %04d: %s" % (index, case.description) _test = _make_test_func(case) _test.__name__ = name _test.description = case.description _test.case = case _test.index = index if hasattr(case.func, "paramList"): _test.paramList = case.func.paramList attr[name] = _test # for collection and sorting attr[case.description] = _test # for random access by name setups = getattr(parent_layer, "testSetups", []) + group._test_setups if setups: def setUp(self): for func in setups: util.call_with_args_if_expected(func, self) attr["setUp"] = setUp teardowns = ( getattr(parent_layer, "testTeardowns", []) + group._test_teardowns[:] ) if teardowns: def tearDown(self): for func in teardowns: util.call_with_args_if_expected(func, self) attr["tearDown"] = tearDown def methodDescription(self): return getattr(self, self._testMethodName).description attr["methodDescription"] = methodDescription return type(group.description, (unittest.TestCase,), attr) def _makeLayer(self, group, parent_layer=None, position=0): if parent_layer is None: parent_layer = object def setUp(cls): for func in cls.setups: util.call_with_args_if_expected(func, self) def tearDown(cls): for func in cls.teardowns: util.call_with_args_if_expected(func, self) attr = { "description": group.description, "setUp": classmethod(setUp), "tearDown": classmethod(tearDown), "setups": group._setups[:], "testSetups": getattr(parent_layer, "testSetups", []) + group._test_setups, "teardowns": group._teardowns[:], "testTeardowns": getattr(parent_layer, "testTeardowns", []) + group._test_teardowns[:], "position": position, "mixins": (), } if group.base_layer: # inject this layer into the group class list # by making it a subclass of parent_layer layer = group.base_layer if parent_layer not in layer.__bases__: layer.mixins = (parent_layer,) else: layer = type("%s:layer" % group.description, (parent_layer,), attr) if group.mixins: layer.mixins = getattr(layer, "mixins", ()) + tuple(group.mixins) log.debug( "made layer %s with bases %s and mixins %s", layer, layer.__bases__, layer.mixins, ) return layer
class Group: """A group of tests, with common fixtures and description""" def __init__(self, description, indent=0, parent=None, base_layer=None): self.description = description self.indent = indent self.parent = parent self.base_layer = base_layer self.mixins = [] self._cases = [] self._setups = [] self._teardowns = [] self._test_setups = [] self._test_teardowns = [] self._children = [] def addCase(self, case): if not self._cases: case.first = True case.indent = self.indent self._cases.append(case) def addSetup(self, func): self._setups.append(func) def addTeardown(self, func): self._teardowns.append(func) def addTestSetUp(self, func): self._test_setups.append(func) def addTestTearDown(self, func): self._test_teardowns.append(func) def fullDescription(self): d = [] p = self.parent while p: d.insert(0, p.description) p = p.parent d.append(self.description) return " ".join(d) def child(self, description, base_layer=None): child = Group(description, self.indent + 1, self, base_layer) self._children.append(child) return child class Case: """Information about a test case""" _helper = helper def __init__(self, group, func, description): self.group = group self.func = func self.description = description self._setups = [] self._teardowns = [] self.first = False self.full = False def __call__(self, testcase, *args): # ... only if it takes an arg self._helper = testcase util.call_with_args_if_expected(self.func, testcase, *args) def __getattr__(self, attr): return getattr(self._helper, attr)