"""
Test Loader
-----------
nose's test loader implements the same basic functionality as its
superclass, unittest.TestLoader, but extends it by more liberal
interpretations of what may be a test and how a test may be named.
"""
from __future__ import generators
import logging
import os
import sys
import unittest
import types
from inspect import isfunction
from nose.pyversion import unbound_method, ismethod
from nose.case import FunctionTestCase, MethodTestCase
from nose.failure import Failure
from nose.config import Config
from nose.importer import Importer, add_path, remove_path
from nose.selector import defaultSelector, TestAddress
from nose.util import func_lineno, getpackage, isclass, isgenerator, \
ispackage, regex_last_key, resolve_name, transplant_func, \
transplant_class, test_address
from nose.suite import ContextSuiteFactory, ContextList, LazySuite
from nose.pyversion import sort_list, cmp_to_key
log = logging.getLogger(__name__)
#log.setLevel(logging.DEBUG)
# for efficiency and easier mocking
op_normpath = os.path.normpath
op_abspath = os.path.abspath
op_join = os.path.join
op_isdir = os.path.isdir
op_isfile = os.path.isfile
__all__ = ['TestLoader', 'defaultTestLoader']
class TestLoader(unittest.TestLoader):
"""Test loader that extends unittest.TestLoader to:
* Load tests from test-like functions and classes that are not
unittest.TestCase subclasses
* Find and load test modules in a directory
* Support tests that are generators
* Support easy extensions of or changes to that behavior through plugins
"""
config = None
importer = None
workingDir = None
selector = None
suiteClass = None
def __init__(self, config=None, importer=None, workingDir=None,
selector=None):
"""Initialize a test loader.
Parameters (all optional):
* config: provide a `nose.config.Config`_ or other config class
instance; if not provided a `nose.config.Config`_ with
default values is used.
* importer: provide an importer instance that implements
`importFromPath`. If not provided, a
`nose.importer.Importer`_ is used.
* workingDir: the directory to which file and module names are
relative. If not provided, assumed to be the current working
directory.
* selector: a selector class or instance. If a class is
provided, it will be instantiated with one argument, the
current config. If not provided, a `nose.selector.Selector`_
is used.
"""
if config is None:
config = Config()
if importer is None:
importer = Importer(config=config)
if workingDir is None:
workingDir = config.workingDir
if selector is None:
selector = defaultSelector(config)
elif isclass(selector):
selector = selector(config)
self.config = config
self.importer = importer
self.workingDir = op_normpath(op_abspath(workingDir))
self.selector = selector
if config.addPaths:
add_path(workingDir, config)
self.suiteClass = ContextSuiteFactory(config=config)
self._visitedPaths = set([])
unittest.TestLoader.__init__(self)
def getTestCaseNames(self, testCaseClass):
"""Override to select with selector, unless
config.getTestCaseNamesCompat is True
"""
if self.config.getTestCaseNamesCompat:
return unittest.TestLoader.getTestCaseNames(self, testCaseClass)
def wanted(attr, cls=testCaseClass, sel=self.selector):
item = getattr(cls, attr, None)
if isfunction(item):
item = unbound_method(cls, item)
elif not ismethod(item):
return False
return sel.wantMethod(item)
cases = filter(wanted, dir(testCaseClass))
for base in testCaseClass.__bases__:
for case in self.getTestCaseNames(base):
if case not in cases:
cases.append(case)
# add runTest if nothing else picked
if not cases and hasattr(testCaseClass, 'runTest'):
cases = ['runTest']
if self.sortTestMethodsUsing:
sort_list(cases, cmp_to_key(self.sortTestMethodsUsing))
return cases
def _haveVisited(self, path):
# For cases where path is None, we always pretend we haven't visited
# them.
if path is None:
return False
return path in self._visitedPaths
def _addVisitedPath(self, path):
if path is not None:
self._visitedPaths.add(path)
def loadTestsFromDir(self, path):
"""Load tests from the directory at path. This is a generator
-- each suite of tests from a module or other file is yielded
and is expected to be executed before the next file is
examined.
"""
log.debug("load from dir %s", path)
plugins = self.config.plugins
plugins.beforeDirectory(path)
if self.config.addPaths:
paths_added = add_path(path, self.config)
entries = os.listdir(path)
sort_list(entries, regex_last_key(self.config.testMatch))
for entry in entries:
# this hard-coded initial-dot test will be removed:
# http://code.google.com/p/python-nose/issues/detail?id=82
if entry.startswith('.'):
continue
entry_path = op_abspath(op_join(path, entry))
is_file = op_isfile(entry_path)
wanted = False
if is_file:
is_dir = False
wanted = self.selector.wantFile(entry_path)
else:
is_dir = op_isdir(entry_path)
if is_dir:
# this hard-coded initial-underscore test will be removed:
# http://code.google.com/p/python-nose/issues/detail?id=82
if entry.startswith('_'):
continue
wanted = self.selector.wantDirectory(entry_path)
is_package = ispackage(entry_path)
# Python 3.3 now implements PEP 420: Implicit Namespace Packages.
# As a result, it's now possible that parent paths that have a
# segment with the same basename as our package ends up
# in module.__path__. So we have to keep track of what we've
# visited, and not-revisit them again.
if wanted and not self._haveVisited(entry_path):
self._addVisitedPath(entry_path)
if is_file:
plugins.beforeContext()
if entry.endswith('.py'):
yield self.loadTestsFromName(
entry_path, discovered=True)
else:
yield self.loadTestsFromFile(entry_path)
plugins.afterContext()
elif is_package:
# Load the entry as a package: given the full path,
# loadTestsFromName() will figure it out
yield self.loadTestsFromName(
entry_path, discovered=True)
else:
# Another test dir in this one: recurse lazily
yield self.suiteClass(
lambda: self.loadTestsFromDir(entry_path))
tests = []
for test in plugins.loadTestsFromDir(path):
tests.append(test)
# TODO: is this try/except needed?
try:
if tests:
yield self.suiteClass(tests)
except (KeyboardInterrupt, SystemExit):
raise
except:
yield self.suiteClass([Failure(*sys.exc_info())])
# pop paths
if self.config.addPaths:
for p in paths_added:
remove_path(p)
plugins.afterDirectory(path)
def loadTestsFromFile(self, filename):
"""Load tests from a non-module file. Default is to raise a
ValueError; plugins may implement `loadTestsFromFile` to
provide a list of tests loaded from the file.
"""
log.debug("Load from non-module file %s", filename)
try:
tests = [test for test in
self.config.plugins.loadTestsFromFile(filename)]
if tests:
# Plugins can yield False to indicate that they were
# unable to load tests from a file, but it was not an
# error -- the file just had no tests to load.
tests = filter(None, tests)
return self.suiteClass(tests)
else:
# Nothing was able to even try to load from this file
open(filename, 'r').close() # trigger os error
raise ValueError("Unable to load tests from file %s"
% filename)
except (KeyboardInterrupt, SystemExit):
raise
except:
exc = sys.exc_info()
return self.suiteClass(
[Failure(exc[0], exc[1], exc[2],
address=(filename, None, None))])
def loadTestsFromGenerator(self, generator, module):
"""Lazy-load tests from a generator function. The generator function
may yield either:
* a callable, or
* a function name resolvable within the same module
"""
def generate(g=generator, m=module):
try:
for test in g():
test_func, arg = self.parseGeneratedTest(test)
if not callable(test_func):
test_func = getattr(m, test_func)
yield FunctionTestCase(test_func, arg=arg, descriptor=g)
except KeyboardInterrupt:
raise
except:
exc = sys.exc_info()
yield Failure(exc[0], exc[1], exc[2],
address=test_address(generator))
return self.suiteClass(generate, context=generator, can_split=False)
def loadTestsFromGeneratorMethod(self, generator, cls):
"""Lazy-load tests from a generator method.
This is more complicated than loading from a generator function,
since a generator method may yield:
* a function
* a bound or unbound method, or
* a method name
"""
# convert the unbound generator method
# into a bound method so it can be called below
if hasattr(generator, 'im_class'):
cls = generator.im_class
inst = cls()
method = generator.__name__
generator = getattr(inst, method)
def generate(g=generator, c=cls):
try:
for test in g():
test_func, arg = self.parseGeneratedTest(test)
if not callable(test_func):
test_func = unbound_method(c, getattr(c, test_func))
if ismethod(test_func):
yield MethodTestCase(test_func, arg=arg, descriptor=g)
elif isfunction(test_func):
# In this case we're forcing the 'MethodTestCase'
# to run the inline function as its test call,
# but using the generator method as the 'method of
# record' (so no need to pass it as the descriptor)
yield MethodTestCase(g, test=test_func, arg=arg)
else:
yield Failure(
TypeError,
"%s is not a function or method" % test_func)
except KeyboardInterrupt:
raise
except:
exc = sys.exc_info()
yield Failure(exc[0], exc[1], exc[2],
address=test_address(generator))
return self.suiteClass(generate, context=generator, can_split=False)
def loadTestsFromModule(self, module, path=None, discovered=False):
"""Load all tests from module and return a suite containing
them. If the module has been discovered and is not test-like,
the suite will be empty by default, though plugins may add
their own tests.
"""
log.debug("Load from module %s", module)
tests = []
test_classes = []
test_funcs = []
# For *discovered* modules, we only load tests when the module looks
# testlike. For modules we've been directed to load, we always
# look for tests. (discovered is set to True by loadTestsFromDir)
if not discovered or self.selector.wantModule(module):
for item in dir(module):
test = getattr(module, item, None)
# print "Check %s (%s) in %s" % (item, test, module.__name__)
if isclass(test):
if self.selector.wantClass(test):
test_classes.append(test)
elif isfunction(test) and self.selector.wantFunction(test):
test_funcs.append(test)
sort_list(test_classes, lambda x: x.__name__)
sort_list(test_funcs, func_lineno)
tests = map(lambda t: self.makeTest(t, parent=module),
test_classes + test_funcs)
# Now, descend into packages
# FIXME can or should this be lazy?
# is this syntax 2.2 compatible?
module_paths = getattr(module, '__path__', [])
if path:
path = os.path.realpath(path)
for module_path in module_paths:
log.debug("Load tests from module path %s?", module_path)
log.debug("path: %s os.path.realpath(%s): %s",
path, module_path, os.path.realpath(module_path))
if (self.config.traverseNamespace or not path) or \
os.path.realpath(module_path).startswith(path):
tests.extend(self.loadTestsFromDir(module_path))
for test in self.config.plugins.loadTestsFromModule(module, path):
tests.append(test)
return self.suiteClass(ContextList(tests, context=module))
def loadTestsFromName(self, name, module=None, discovered=False):
"""Load tests from the entity with the given name.
The name may indicate a file, directory, module, or any object
within a module. See `nose.util.split_test_name` for details on
test name parsing.
"""
# FIXME refactor this method into little bites?
log.debug("load from %s (%s)", name, module)
suite = self.suiteClass
# give plugins first crack
plug_tests = self.config.plugins.loadTestsFromName(name, module)
if plug_tests:
return suite(plug_tests)
addr = TestAddress(name, workingDir=self.workingDir)
if module:
# Two cases:
# name is class.foo
# The addr will be incorrect, since it thinks class.foo is
# a dotted module name. It's actually a dotted attribute
# name. In this case we want to use the full submitted
# name as the name to load from the module.
# name is module:class.foo
# The addr will be correct. The part we want is the part after
# the :, which is in addr.call.
if addr.call:
name = addr.call
parent, obj = self.resolve(name, module)
if (isclass(parent)
and getattr(parent, '__module__', None) != module.__name__
and not isinstance(obj, Failure)):
parent = transplant_class(parent, module.__name__)
obj = getattr(parent, obj.__name__)
log.debug("parent %s obj %s module %s", parent, obj, module)
if isinstance(obj, Failure):
return suite([obj])
else:
return suite(ContextList([self.makeTest(obj, parent)],
context=parent))
else:
if addr.module:
try:
if addr.filename is None:
module = resolve_name(addr.module)
else:
self.config.plugins.beforeImport(
addr.filename, addr.module)
# FIXME: to support module.name names,
# do what resolve-name does and keep trying to
# import, popping tail of module into addr.call,
# until we either get an import or run out of
# module parts
try:
module = self.importer.importFromPath(
addr.filename, addr.module)
finally:
self.config.plugins.afterImport(
addr.filename, addr.module)
except (KeyboardInterrupt, SystemExit):
raise
except:
exc = sys.exc_info()
return suite([Failure(exc[0], exc[1], exc[2],
address=addr.totuple())])
if addr.call:
return self.loadTestsFromName(addr.call, module)
else:
return self.loadTestsFromModule(
module, addr.filename,
discovered=discovered)
elif addr.filename:
path = addr.filename
if addr.call:
package = getpackage(path)
if package is None:
return suite([
Failure(ValueError,
"Can't find callable %s in file %s: "
"file is not a python module" %
(addr.call, path),
address=addr.totuple())])
return self.loadTestsFromName(addr.call, module=package)
else:
if op_isdir(path):
# In this case we *can* be lazy since we know
# that each module in the dir will be fully
# loaded before its tests are executed; we
# also know that we're not going to be asked
# to load from . and ./some_module.py *as part
# of this named test load*
return LazySuite(
lambda: self.loadTestsFromDir(path))
elif op_isfile(path):
return self.loadTestsFromFile(path)
else:
return suite([
Failure(OSError, "No such file %s" % path,
address=addr.totuple())])
else:
# just a function? what to do? I think it can only be
# handled when module is not None
return suite([
Failure(ValueError, "Unresolvable test name %s" % name,
address=addr.totuple())])
def loadTestsFromNames(self, names, module=None):
"""Load tests from all names, returning a suite containing all
tests.
"""
plug_res = self.config.plugins.loadTestsFromNames(names, module)
if plug_res:
suite, names = plug_res
if suite:
return self.suiteClass([
self.suiteClass(suite),
unittest.TestLoader.loadTestsFromNames(self, names, module)
])
return unittest.TestLoader.loadTestsFromNames(self, names, module)
def loadTestsFromTestCase(self, testCaseClass):
"""Load tests from a unittest.TestCase subclass.
"""
cases = []
plugins = self.config.plugins
for case in plugins.loadTestsFromTestCase(testCaseClass):
cases.append(case)
# For efficiency in the most common case, just call and return from
# super. This avoids having to extract cases and rebuild a context
# suite when there are no plugin-contributed cases.
if not cases:
return super(TestLoader, self).loadTestsFromTestCase(testCaseClass)
cases.extend(
[case for case in
super(TestLoader, self).loadTestsFromTestCase(testCaseClass)])
return self.suiteClass(cases)
def loadTestsFromTestClass(self, cls):
"""Load tests from a test class that is *not* a unittest.TestCase
subclass.
In this case, we can't depend on the class's `__init__` taking method
name arguments, so we have to compose a MethodTestCase for each
method in the class that looks testlike.
"""
def wanted(attr, cls=cls, sel=self.selector):
item = getattr(cls, attr, None)
if isfunction(item):
item = unbound_method(cls, item)
elif not ismethod(item):
return False
return sel.wantMethod(item)
cases = [self.makeTest(getattr(cls, case), cls)
for case in filter(wanted, dir(cls))]
for test in self.config.plugins.loadTestsFromTestClass(cls):
cases.append(test)
return self.suiteClass(ContextList(cases, context=cls))
def makeTest(self, obj, parent=None):
try:
return self._makeTest(obj, parent)
except (KeyboardInterrupt, SystemExit):
raise
except:
exc = sys.exc_info()
try:
addr = test_address(obj)
except KeyboardInterrupt:
raise
except:
addr = None
return Failure(exc[0], exc[1], exc[2], address=addr)
def _makeTest(self, obj, parent=None):
"""Given a test object and its parent, return a test case
or test suite.
"""
plug_tests = []
try:
addr = test_address(obj)
except KeyboardInterrupt:
raise
except:
addr = None
for test in self.config.plugins.makeTest(obj, parent):
plug_tests.append(test)
# TODO: is this try/except needed?
try:
if plug_tests:
return self.suiteClass(plug_tests)
except (KeyboardInterrupt, SystemExit):
raise
except:
exc = sys.exc_info()
return Failure(exc[0], exc[1], exc[2], address=addr)
if isfunction(obj) and parent and not isinstance(parent, types.ModuleType):
# This is a Python 3.x 'unbound method'. Wrap it with its
# associated class..
obj = unbound_method(parent, obj)
if isinstance(obj, unittest.TestCase):
return obj
elif isclass(obj):
if parent and obj.__module__ != parent.__name__:
obj = transplant_class(obj, parent.__name__)
if issubclass(obj, unittest.TestCase):
return self.loadTestsFromTestCase(obj)
else:
return self.loadTestsFromTestClass(obj)
elif ismethod(obj):
if parent is None:
parent = obj.__class__
if issubclass(parent, unittest.TestCase):
return parent(obj.__name__)
else:
if isgenerator(obj):
return self.loadTestsFromGeneratorMethod(obj, parent)
else:
return MethodTestCase(obj)
elif isfunction(obj):
if parent and obj.__module__ != parent.__name__:
obj = transplant_func(obj, parent.__name__)
if isgenerator(obj):
return self.loadTestsFromGenerator(obj, parent)
else:
return FunctionTestCase(obj)
else:
return Failure(TypeError,
"Can't make a test from %s" % obj,
address=addr)
def resolve(self, name, module):
"""Resolve name within module
"""
obj = module
parts = name.split('.')
for part in parts:
parent, obj = obj, getattr(obj, part, None)
if obj is None:
# no such test
obj = Failure(ValueError, "No such test %s" % name)
return parent, obj
def parseGeneratedTest(self, test):
"""Given the yield value of a test generator, return a func and args.
This is used in the two loadTestsFromGenerator* methods.
"""
if not isinstance(test, tuple): # yield test
test_func, arg = (test, tuple())
elif len(test) == 1: # yield (test,)
test_func, arg = (test[0], tuple())
else: # yield test, foo, bar, ...
assert len(test) > 1 # sanity check
test_func, arg = (test[0], test[1:])
return test_func, arg
defaultTestLoader = TestLoader
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