Lib.test.test_support.py Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jython Show documentation
Show all versions of jython Show documentation
Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
"""Supporting definitions for the Python regression tests."""
if __name__ != 'test.test_support':
raise ImportError('test_support must be imported from the test package')
import contextlib
import errno
import functools
import gc
import socket
import sys
import os
import platform
import shutil
import warnings
import unittest
import importlib
import UserDict
import re
import time
import struct
import sysconfig
try:
import _testcapi
except ImportError:
_testcapi = None
try:
import thread
except ImportError:
thread = None
__all__ = ["Error", "TestFailed", "ResourceDenied", "import_module",
"verbose", "use_resources", "max_memuse", "record_original_stdout",
"get_original_stdout", "unload", "unlink", "rmtree", "forget",
"is_resource_enabled", "requires", "find_unused_port", "bind_port",
"fcmp", "have_unicode", "is_jython", "TESTFN", "HOST", "FUZZ",
"SAVEDCWD", "temp_cwd", "findfile", "sortdict", "check_syntax_error",
"open_urlresource", "check_warnings", "check_py3k_warnings",
"CleanImport", "EnvironmentVarGuard", "captured_output",
"captured_stdout", "TransientResource", "transient_internet",
"run_with_locale", "set_memlimit", "bigmemtest", "bigaddrspacetest",
"BasicTestRunner", "run_unittest", "run_doctest", "threading_setup",
"threading_cleanup", "reap_children", "cpython_only",
"check_impl_detail", "get_attribute", "py3k_bytes",
"import_fresh_module", "threading_cleanup", "reap_children",
"strip_python_stderr"]
class Error(Exception):
"""Base class for regression test exceptions."""
class TestFailed(Error):
"""Test failed."""
class ResourceDenied(unittest.SkipTest):
"""Test skipped because it requested a disallowed resource.
This is raised when a test calls requires() for a resource that
has not be enabled. It is used to distinguish between expected
and unexpected skips.
"""
@contextlib.contextmanager
def _ignore_deprecated_imports(ignore=True):
"""Context manager to suppress package and module deprecation
warnings when importing them.
If ignore is False, this context manager has no effect."""
if ignore:
with warnings.catch_warnings():
warnings.filterwarnings("ignore", ".+ (module|package)",
DeprecationWarning)
yield
else:
yield
def import_module(name, deprecated=False):
"""Import and return the module to be tested, raising SkipTest if
it is not available.
If deprecated is True, any module or package deprecation messages
will be suppressed."""
with _ignore_deprecated_imports(deprecated):
try:
return importlib.import_module(name)
except ImportError, msg:
raise unittest.SkipTest(str(msg))
def _save_and_remove_module(name, orig_modules):
"""Helper function to save and remove a module from sys.modules
Raise ImportError if the module can't be imported."""
# try to import the module and raise an error if it can't be imported
if name not in sys.modules:
__import__(name)
del sys.modules[name]
for modname in list(sys.modules):
if modname == name or modname.startswith(name + '.'):
orig_modules[modname] = sys.modules[modname]
del sys.modules[modname]
def _save_and_block_module(name, orig_modules):
"""Helper function to save and block a module in sys.modules
Return True if the module was in sys.modules, False otherwise."""
saved = True
try:
orig_modules[name] = sys.modules[name]
except KeyError:
saved = False
sys.modules[name] = None
return saved
def import_fresh_module(name, fresh=(), blocked=(), deprecated=False):
"""Imports and returns a module, deliberately bypassing the sys.modules cache
and importing a fresh copy of the module. Once the import is complete,
the sys.modules cache is restored to its original state.
Modules named in fresh are also imported anew if needed by the import.
If one of these modules can't be imported, None is returned.
Importing of modules named in blocked is prevented while the fresh import
takes place.
If deprecated is True, any module or package deprecation messages
will be suppressed."""
# NOTE: test_heapq, test_json, and test_warnings include extra sanity
# checks to make sure that this utility function is working as expected
with _ignore_deprecated_imports(deprecated):
# Keep track of modules saved for later restoration as well
# as those which just need a blocking entry removed
orig_modules = {}
names_to_remove = []
_save_and_remove_module(name, orig_modules)
try:
for fresh_name in fresh:
_save_and_remove_module(fresh_name, orig_modules)
for blocked_name in blocked:
if not _save_and_block_module(blocked_name, orig_modules):
names_to_remove.append(blocked_name)
fresh_module = importlib.import_module(name)
except ImportError:
fresh_module = None
finally:
for orig_name, module in orig_modules.items():
sys.modules[orig_name] = module
for name_to_remove in names_to_remove:
del sys.modules[name_to_remove]
return fresh_module
def get_attribute(obj, name):
"""Get an attribute, raising SkipTest if AttributeError is raised."""
try:
attribute = getattr(obj, name)
except AttributeError:
raise unittest.SkipTest("module %s has no attribute %s" % (
obj.__name__, name))
else:
return attribute
verbose = 1 # Flag set to 0 by regrtest.py
use_resources = None # Flag set to [] by regrtest.py
junit_xml_dir = None # Option set by regrtest.py
max_memuse = 0 # Disable bigmem tests (they will still be run with
# small sizes, to make sure they work.)
real_max_memuse = 0
# _original_stdout is meant to hold stdout at the time regrtest began.
# This may be "the real" stdout, or IDLE's emulation of stdout, or whatever.
# The point is to have some flavor of stdout the user can actually see.
_original_stdout = None
def record_original_stdout(stdout):
global _original_stdout
_original_stdout = stdout
def get_original_stdout():
return _original_stdout or sys.stdout
def unload(name):
try:
del sys.modules[name]
except KeyError:
pass
if sys.platform.startswith("win") or (os.name == "java" and os._name == "nt"):
def _waitfor(func, pathname, waitall=False):
# Peform the operation
func(pathname)
# Now setup the wait loop
if waitall:
dirname = pathname
else:
dirname, name = os.path.split(pathname)
dirname = dirname or '.'
# Check for `pathname` to be removed from the filesystem.
# The exponential backoff of the timeout amounts to a total
# of ~1 second after which the deletion is probably an error
# anyway.
# Testing on a [email protected] shows that usually only 1 iteration is
# required when contention occurs.
timeout = 0.001
while timeout < 1.0:
# Note we are only testing for the existance of the file(s) in
# the contents of the directory regardless of any security or
# access rights. If we have made it this far, we have sufficient
# permissions to do that much using Python's equivalent of the
# Windows API FindFirstFile.
# Other Windows APIs can fail or give incorrect results when
# dealing with files that are pending deletion.
L = os.listdir(dirname)
if not (L if waitall else name in L):
return
# Increase the timeout and try again
time.sleep(timeout)
timeout *= 2
print "Still cannot delete", pathname
warnings.warn('tests may fail, delete still pending for ' + pathname,
RuntimeWarning, stacklevel=4)
def _unlink(filename):
_waitfor(os.unlink, filename)
def _rmdir(dirname):
_waitfor(os.rmdir, dirname)
def _rmtree(path):
def _rmtree_inner(path):
for name in os.listdir(path):
fullname = os.path.join(path, name)
if os.path.isdir(fullname):
_waitfor(_rmtree_inner, fullname, waitall=True)
os.rmdir(fullname)
else:
os.unlink(fullname)
_waitfor(_rmtree_inner, path, waitall=True)
_waitfor(os.rmdir, path)
else:
_unlink = os.unlink
_rmdir = os.rmdir
_rmtree = shutil.rmtree
def unlink(filename):
try:
_unlink(filename)
except OSError:
pass
def rmdir(dirname):
try:
_rmdir(dirname)
except OSError as error:
# The directory need not exist.
if error.errno != errno.ENOENT:
raise
def rmtree(path):
try:
_rmtree(path)
except OSError, e:
# Unix returns ENOENT, Windows returns ESRCH.
if e.errno not in (errno.ENOENT, errno.ESRCH):
raise
def forget(modname):
'''"Forget" a module was ever imported by removing it from sys.modules and
deleting any .pyc and .pyo files.'''
unload(modname)
for dirname in sys.path:
unlink(os.path.join(dirname, modname + os.extsep + 'pyc'))
# Deleting the .pyo file cannot be within the 'try' for the .pyc since
# the chance exists that there is no .pyc (and thus the 'try' statement
# is exited) but there is a .pyo file.
unlink(os.path.join(dirname, modname + os.extsep + 'pyo'))
def is_resource_enabled(resource):
"""Test whether a resource is enabled. Known resources are set by
regrtest.py."""
return use_resources is not None and resource in use_resources
def requires(resource, msg=None):
"""Raise ResourceDenied if the specified resource is not available.
If the caller's module is __main__ then automatically return True. The
possibility of False being returned occurs when regrtest.py is executing."""
# see if the caller's module is __main__ - if so, treat as if
# the resource was set
if sys._getframe().f_back.f_globals.get("__name__") == "__main__":
return
if not is_resource_enabled(resource):
if msg is None:
msg = "Use of the `%s' resource not enabled" % resource
raise ResourceDenied(msg)
HOST = 'localhost'
def find_unused_port(family=socket.AF_INET, socktype=socket.SOCK_STREAM):
"""Returns an unused port that should be suitable for binding. This is
achieved by creating a temporary socket with the same family and type as
the 'sock' parameter (default is AF_INET, SOCK_STREAM), and binding it to
the specified host address (defaults to 0.0.0.0) with the port set to 0,
eliciting an unused ephemeral port from the OS. The temporary socket is
then closed and deleted, and the ephemeral port is returned.
Either this method or bind_port() should be used for any tests where a
server socket needs to be bound to a particular port for the duration of
the test. Which one to use depends on whether the calling code is creating
a python socket, or if an unused port needs to be provided in a constructor
or passed to an external program (i.e. the -accept argument to openssl's
s_server mode). Always prefer bind_port() over find_unused_port() where
possible. Hard coded ports should *NEVER* be used. As soon as a server
socket is bound to a hard coded port, the ability to run multiple instances
of the test simultaneously on the same host is compromised, which makes the
test a ticking time bomb in a buildbot environment. On Unix buildbots, this
may simply manifest as a failed test, which can be recovered from without
intervention in most cases, but on Windows, the entire python process can
completely and utterly wedge, requiring someone to log in to the buildbot
and manually kill the affected process.
(This is easy to reproduce on Windows, unfortunately, and can be traced to
the SO_REUSEADDR socket option having different semantics on Windows versus
Unix/Linux. On Unix, you can't have two AF_INET SOCK_STREAM sockets bind,
listen and then accept connections on identical host/ports. An EADDRINUSE
socket.error will be raised at some point (depending on the platform and
the order bind and listen were called on each socket).
However, on Windows, if SO_REUSEADDR is set on the sockets, no EADDRINUSE
will ever be raised when attempting to bind two identical host/ports. When
accept() is called on each socket, the second caller's process will steal
the port from the first caller, leaving them both in an awkwardly wedged
state where they'll no longer respond to any signals or graceful kills, and
must be forcibly killed via OpenProcess()/TerminateProcess().
The solution on Windows is to use the SO_EXCLUSIVEADDRUSE socket option
instead of SO_REUSEADDR, which effectively affords the same semantics as
SO_REUSEADDR on Unix. Given the propensity of Unix developers in the Open
Source world compared to Windows ones, this is a common mistake. A quick
look over OpenSSL's 0.9.8g source shows that they use SO_REUSEADDR when
openssl.exe is called with the 's_server' option, for example. See
http://bugs.python.org/issue2550 for more info. The following site also
has a very thorough description about the implications of both REUSEADDR
and EXCLUSIVEADDRUSE on Windows:
http://msdn2.microsoft.com/en-us/library/ms740621(VS.85).aspx)
XXX: although this approach is a vast improvement on previous attempts to
elicit unused ports, it rests heavily on the assumption that the ephemeral
port returned to us by the OS won't immediately be dished back out to some
other process when we close and delete our temporary socket but before our
calling code has a chance to bind the returned port. We can deal with this
issue if/when we come across it."""
tempsock = socket.socket(family, socktype)
port = bind_port(tempsock)
tempsock.close()
del tempsock
return port
def bind_port(sock, host=HOST):
"""Bind the socket to a free port and return the port number. Relies on
ephemeral ports in order to ensure we are using an unbound port. This is
important as many tests may be running simultaneously, especially in a
buildbot environment. This method raises an exception if the sock.family
is AF_INET and sock.type is SOCK_STREAM, *and* the socket has SO_REUSEADDR
or SO_REUSEPORT set on it. Tests should *never* set these socket options
for TCP/IP sockets. The only case for setting these options is testing
multicasting via multiple UDP sockets.
Additionally, if the SO_EXCLUSIVEADDRUSE socket option is available (i.e.
on Windows), it will be set on the socket. This will prevent anyone else
from bind()'ing to our host/port for the duration of the test.
"""
if is_jython:
# Late binding of the jython socket implementation to a
# ServerSocketChannel or SocketChannel means that it's not possible to
# get the port until a call to connect() or listen(). Hence why a new
# socket is created and listen() is called on it.
tempsock = socket.socket(sock.family, sock.type)
tempsock.bind((host, 0))
tempsock.listen(1)
port = tempsock.getsockname()[1]
tempsock.close()
del tempsock
sock.bind((host, port))
return port
elif sock.family == socket.AF_INET and sock.type == socket.SOCK_STREAM:
if hasattr(socket, 'SO_REUSEADDR'):
if sock.getsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR) == 1:
raise TestFailed("tests should never set the SO_REUSEADDR " \
"socket option on TCP/IP sockets!")
if hasattr(socket, 'SO_REUSEPORT'):
if sock.getsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT) == 1:
raise TestFailed("tests should never set the SO_REUSEPORT " \
"socket option on TCP/IP sockets!")
if hasattr(socket, 'SO_EXCLUSIVEADDRUSE'):
sock.setsockopt(socket.SOL_SOCKET, socket.SO_EXCLUSIVEADDRUSE, 1)
sock.bind((host, 0))
port = sock.getsockname()[1]
return port
FUZZ = 1e-6
def fcmp(x, y): # fuzzy comparison function
if isinstance(x, float) or isinstance(y, float):
try:
fuzz = (abs(x) + abs(y)) * FUZZ
if abs(x-y) <= fuzz:
return 0
except:
pass
elif type(x) == type(y) and isinstance(x, (tuple, list)):
for i in range(min(len(x), len(y))):
outcome = fcmp(x[i], y[i])
if outcome != 0:
return outcome
return (len(x) > len(y)) - (len(x) < len(y))
return (x > y) - (x < y)
try:
unicode
have_unicode = True
except NameError:
have_unicode = False
is_jython = sys.platform.startswith('java')
if is_jython:
def make_jar_classloader(jar):
import os
from java.net import URL, URLClassLoader
url = URL('jar:file:%s!/' % jar)
if os._name == 'nt':
# URLJarFiles keep a cached open file handle to the jar even
# after this ClassLoader is GC'ed, disallowing Windows tests
# from removing the jar file from disk when finished with it
conn = url.openConnection()
if conn.getDefaultUseCaches():
# XXX: Globally turn off jar caching: this stupid
# instance method actually toggles a static flag. Need a
# better fix
conn.setDefaultUseCaches(False)
return URLClassLoader([url])
# Filename used for testing
if os.name == 'java':
# Jython disallows @ in module names
TESTFN = '$test'
elif os.name == 'riscos':
TESTFN = 'testfile'
else:
TESTFN = '@test'
# Unicode name only used if TEST_FN_ENCODING exists for the platform.
if have_unicode:
# Assuming sys.getfilesystemencoding()!=sys.getdefaultencoding()
# TESTFN_UNICODE is a filename that can be encoded using the
# file system encoding, but *not* with the default (ascii) encoding
if isinstance('', unicode):
# python -U
# XXX perhaps unicode() should accept Unicode strings?
TESTFN_UNICODE = "@test-\xe0\xf2"
else:
# 2 latin characters.
TESTFN_UNICODE = unicode("@test-\xe0\xf2", "latin-1")
TESTFN_ENCODING = sys.getfilesystemencoding()
# TESTFN_UNICODE_UNENCODEABLE is a filename that should *not* be
# able to be encoded by *either* the default or filesystem encoding.
# This test really only makes sense on Windows NT platforms
# which have special Unicode support in posixmodule.
if (not hasattr(sys, "getwindowsversion") or
sys.getwindowsversion()[3] < 2): # 0=win32s or 1=9x/ME
TESTFN_UNICODE_UNENCODEABLE = None
else:
# Japanese characters (I think - from bug 846133)
TESTFN_UNICODE_UNENCODEABLE = eval('u"@test-\u5171\u6709\u3055\u308c\u308b"')
try:
# XXX - Note - should be using TESTFN_ENCODING here - but for
# Windows, "mbcs" currently always operates as if in
# errors=ignore' mode - hence we get '?' characters rather than
# the exception. 'Latin1' operates as we expect - ie, fails.
# See [ 850997 ] mbcs encoding ignores errors
TESTFN_UNICODE_UNENCODEABLE.encode("Latin1")
except UnicodeEncodeError:
pass
else:
print \
'WARNING: The filename %r CAN be encoded by the filesystem. ' \
'Unicode filename tests may not be effective' \
% TESTFN_UNICODE_UNENCODEABLE
# Make sure we can write to TESTFN, try in /tmp if we can't
fp = None
try:
fp = open(TESTFN, 'w+')
except IOError:
TMP_TESTFN = os.path.join('/tmp', TESTFN)
try:
fp = open(TMP_TESTFN, 'w+')
TESTFN = TMP_TESTFN
del TMP_TESTFN
except IOError:
print ('WARNING: tests will fail, unable to write to: %s or %s' %
(TESTFN, TMP_TESTFN))
if fp is not None:
fp.close()
unlink(TESTFN)
del fp
# Disambiguate TESTFN for parallel testing, while letting it remain a valid
# module name.
TESTFN = "{}_{}_tmp".format(TESTFN, "1") #XXX "1" is a dummy for os.getpid()
# Save the initial cwd
SAVEDCWD = os.getcwd()
@contextlib.contextmanager
def temp_cwd(name='tempcwd', quiet=False):
"""
Context manager that creates a temporary directory and set it as CWD.
The new CWD is created in the current directory and it's named *name*.
If *quiet* is False (default) and it's not possible to create or change
the CWD, an error is raised. If it's True, only a warning is raised
and the original CWD is used.
"""
if have_unicode and isinstance(name, unicode) and not is_jython:
# Jython supports unicode paths
try:
name = name.encode(sys.getfilesystemencoding() or 'ascii')
except UnicodeEncodeError:
if not quiet:
raise unittest.SkipTest('unable to encode the cwd name with '
'the filesystem encoding.')
saved_dir = os.getcwd()
is_temporary = False
try:
os.mkdir(name)
os.chdir(name)
is_temporary = True
except OSError:
if not quiet:
raise
warnings.warn('tests may fail, unable to change the CWD to ' + name,
RuntimeWarning, stacklevel=3)
try:
yield os.getcwd()
finally:
os.chdir(saved_dir)
if is_temporary:
rmtree(name)
def findfile(file, here=__file__, subdir=None):
"""Try to find a file on sys.path and the working directory. If it is not
found the argument passed to the function is returned (this does not
necessarily signal failure; could still be the legitimate path)."""
if os.path.isabs(file):
return file
if subdir is not None:
file = os.path.join(subdir, file)
path = sys.path
path = [os.path.dirname(here)] + path
for dn in path:
fn = os.path.join(dn, file)
if os.path.exists(fn): return fn
return file
def verify(condition, reason='test failed'):
"""Verify that condition is true. If not, raise TestFailed.
The optional argument reason can be given to provide
a better error text.
"""
if not condition:
raise TestFailed(reason)
def vereq(a, b):
"""Raise TestFailed if a == b is false.
This is better than verify(a == b) because, in case of failure, the
error message incorporates repr(a) and repr(b) so you can see the
inputs.
Note that "not (a == b)" isn't necessarily the same as "a != b"; the
former is tested.
"""
if not (a == b):
raise TestFailed("%r == %r" % (a, b))
def sortdict(dict):
"Like repr(dict), but in sorted order."
items = dict.items()
items.sort()
reprpairs = ["%r: %r" % pair for pair in items]
withcommas = ", ".join(reprpairs)
return "{%s}" % withcommas
def make_bad_fd():
"""
Create an invalid file descriptor by opening and closing a file and return
its fd.
"""
file = open(TESTFN, "wb")
try:
return file.fileno()
finally:
file.close()
unlink(TESTFN)
def check_syntax_error(testcase, statement):
try:
compile(statement, '', 'exec')
except SyntaxError:
pass
else:
testcase.fail('Missing SyntaxError: "%s"' % statement)
def open_urlresource(url, check=None):
import urlparse, urllib2
filename = urlparse.urlparse(url)[2].split('/')[-1] # '/': it's URL!
fn = os.path.join(os.path.dirname(__file__), "data", filename)
def check_valid_file(fn):
f = open(fn)
if check is None:
return f
elif check(f):
f.seek(0)
return f
f.close()
if os.path.exists(fn):
f = check_valid_file(fn)
if f is not None:
return f
unlink(fn)
# Verify the requirement before downloading the file
requires('urlfetch')
print >> get_original_stdout(), '\tfetching %s ...' % url
f = urllib2.urlopen(url, timeout=15)
try:
with open(fn, "wb") as out:
s = f.read()
while s:
out.write(s)
s = f.read()
finally:
f.close()
f = check_valid_file(fn)
if f is not None:
return f
raise TestFailed('invalid resource "%s"' % fn)
class WarningsRecorder(object):
"""Convenience wrapper for the warnings list returned on
entry to the warnings.catch_warnings() context manager.
"""
def __init__(self, warnings_list):
self._warnings = warnings_list
self._last = 0
def __getattr__(self, attr):
if len(self._warnings) > self._last:
return getattr(self._warnings[-1], attr)
elif attr in warnings.WarningMessage._WARNING_DETAILS:
return None
raise AttributeError("%r has no attribute %r" % (self, attr))
@property
def warnings(self):
return self._warnings[self._last:]
def reset(self):
self._last = len(self._warnings)
def _filterwarnings(filters, quiet=False):
"""Catch the warnings, then check if all the expected
warnings have been raised and re-raise unexpected warnings.
If 'quiet' is True, only re-raise the unexpected warnings.
"""
# Clear the warning registry of the calling module
# in order to re-raise the warnings.
frame = sys._getframe(2)
registry = frame.f_globals.get('__warningregistry__')
if registry:
registry.clear()
with warnings.catch_warnings(record=True) as w:
# Set filter "always" to record all warnings. Because
# test_warnings swap the module, we need to look up in
# the sys.modules dictionary.
sys.modules['warnings'].simplefilter("always")
yield WarningsRecorder(w)
# Filter the recorded warnings
reraise = [warning.message for warning in w]
missing = []
for msg, cat in filters:
seen = False
for exc in reraise[:]:
message = str(exc)
# Filter out the matching messages
if (re.match(msg, message, re.I) and
issubclass(exc.__class__, cat)):
seen = True
reraise.remove(exc)
if not seen and not quiet:
# This filter caught nothing
missing.append((msg, cat.__name__))
if reraise:
raise AssertionError("unhandled warning %r" % reraise[0])
if missing:
raise AssertionError("filter (%r, %s) did not catch any warning" %
missing[0])
@contextlib.contextmanager
def check_warnings(*filters, **kwargs):
"""Context manager to silence warnings.
Accept 2-tuples as positional arguments:
("message regexp", WarningCategory)
Optional argument:
- if 'quiet' is True, it does not fail if a filter catches nothing
(default True without argument,
default False if some filters are defined)
Without argument, it defaults to:
check_warnings(("", Warning), quiet=True)
"""
quiet = kwargs.get('quiet')
if not filters:
filters = (("", Warning),)
# Preserve backward compatibility
if quiet is None:
quiet = True
return _filterwarnings(filters, quiet)
@contextlib.contextmanager
def check_py3k_warnings(*filters, **kwargs):
"""Context manager to silence py3k warnings.
Accept 2-tuples as positional arguments:
("message regexp", WarningCategory)
Optional argument:
- if 'quiet' is True, it does not fail if a filter catches nothing
(default False)
Without argument, it defaults to:
check_py3k_warnings(("", DeprecationWarning), quiet=False)
"""
if sys.py3kwarning:
if not filters:
filters = (("", DeprecationWarning),)
else:
# It should not raise any py3k warning
filters = ()
return _filterwarnings(filters, kwargs.get('quiet'))
class CleanImport(object):
"""Context manager to force import to return a new module reference.
This is useful for testing module-level behaviours, such as
the emission of a DeprecationWarning on import.
Use like this:
with CleanImport("foo"):
__import__("foo") # new reference
"""
def __init__(self, *module_names):
self.original_modules = sys.modules.copy()
for module_name in module_names:
if module_name in sys.modules:
module = sys.modules[module_name]
# It is possible that module_name is just an alias for
# another module (e.g. stub for modules renamed in 3.x).
# In that case, we also need delete the real module to clear
# the import cache.
if module.__name__ != module_name:
del sys.modules[module.__name__]
del sys.modules[module_name]
def __enter__(self):
return self
def __exit__(self, *ignore_exc):
sys.modules.update(self.original_modules)
class EnvironmentVarGuard(UserDict.DictMixin):
"""Class to help protect the environment variable properly. Can be used as
a context manager."""
def __init__(self):
self._environ = os.environ
self._changed = {}
def __getitem__(self, envvar):
return self._environ[envvar]
def __setitem__(self, envvar, value):
# Remember the initial value on the first access
if envvar not in self._changed:
self._changed[envvar] = self._environ.get(envvar)
self._environ[envvar] = value
def __delitem__(self, envvar):
# Remember the initial value on the first access
if envvar not in self._changed:
self._changed[envvar] = self._environ.get(envvar)
if envvar in self._environ:
del self._environ[envvar]
def keys(self):
return self._environ.keys()
def set(self, envvar, value):
self[envvar] = value
def unset(self, envvar):
del self[envvar]
def __enter__(self):
return self
def __exit__(self, *ignore_exc):
for (k, v) in self._changed.items():
if v is None:
if k in self._environ:
del self._environ[k]
else:
self._environ[k] = v
os.environ = self._environ
class TransientResource(object):
"""Raise ResourceDenied if an exception is raised while the context manager
is in effect that matches the specified exception and attributes."""
def __init__(self, exc, **kwargs):
self.exc = exc
self.attrs = kwargs
def __enter__(self):
return self
def __exit__(self, type_=None, value=None, traceback=None):
"""If type_ is a subclass of self.exc and value has attributes matching
self.attrs, raise ResourceDenied. Otherwise let the exception
propagate (if any)."""
if type_ is not None and issubclass(self.exc, type_):
for attr, attr_value in self.attrs.iteritems():
if not hasattr(value, attr):
break
if getattr(value, attr) != attr_value:
break
else:
raise ResourceDenied("an optional resource is not available")
@contextlib.contextmanager
def transient_internet(resource_name, timeout=30.0, errnos=()):
"""Return a context manager that raises ResourceDenied when various issues
with the Internet connection manifest themselves as exceptions."""
default_errnos = [
('ECONNREFUSED', 111),
('ECONNRESET', 104),
('EHOSTUNREACH', 113),
('ENETUNREACH', 101),
('ETIMEDOUT', 110),
]
default_gai_errnos = [
('EAI_AGAIN', -3),
('EAI_FAIL', -4),
('EAI_NONAME', -2),
('EAI_NODATA', -5),
# Windows defines EAI_NODATA as 11001 but idiotic getaddrinfo()
# implementation actually returns WSANO_DATA i.e. 11004.
('WSANO_DATA', 11004),
]
denied = ResourceDenied("Resource '%s' is not available" % resource_name)
captured_errnos = errnos
gai_errnos = []
if not captured_errnos:
captured_errnos = [getattr(errno, name, num)
for (name, num) in default_errnos]
gai_errnos = [getattr(socket, name, num)
for (name, num) in default_gai_errnos]
def filter_error(err):
n = getattr(err, 'errno', None)
if (isinstance(err, socket.timeout) or
(isinstance(err, socket.gaierror) and n in gai_errnos) or
n in captured_errnos):
if not verbose:
sys.stderr.write(denied.args[0] + "\n")
raise denied
old_timeout = socket.getdefaulttimeout()
try:
if timeout is not None:
socket.setdefaulttimeout(timeout)
yield
except IOError as err:
# urllib can wrap original socket errors multiple times (!), we must
# unwrap to get at the original error.
while True:
a = err.args
if len(a) >= 1 and isinstance(a[0], IOError):
err = a[0]
# The error can also be wrapped as args[1]:
# except socket.error as msg:
# raise IOError('socket error', msg).with_traceback(sys.exc_info()[2])
elif len(a) >= 2 and isinstance(a[1], IOError):
err = a[1]
else:
break
filter_error(err)
raise
# XXX should we catch generic exceptions and look for their
# __cause__ or __context__?
finally:
socket.setdefaulttimeout(old_timeout)
@contextlib.contextmanager
def captured_output(stream_name):
"""Run the 'with' statement body using a StringIO object in place of a
specific attribute on the sys module.
Example use (with 'stream_name=stdout')::
with captured_stdout() as s:
print "hello"
assert s.getvalue() == "hello"
"""
import StringIO
orig_stdout = getattr(sys, stream_name)
setattr(sys, stream_name, StringIO.StringIO())
try:
yield getattr(sys, stream_name)
finally:
setattr(sys, stream_name, orig_stdout)
def captured_stdout():
return captured_output("stdout")
def captured_stderr():
return captured_output("stderr")
def captured_stdin():
return captured_output("stdin")
def gc_collect():
"""Force as many objects as possible to be collected.
In non-CPython implementations of Python, this is needed because timely
deallocation is not guaranteed by the garbage collector. (Even in CPython
this can be the case in case of reference cycles.) This means that __del__
methods may be called later than expected and weakrefs may remain alive for
longer than expected. This function tries its best to force all garbage
objects to disappear.
"""
gc.collect()
if is_jython:
time.sleep(0.1)
gc.collect()
gc.collect()
_header = '2P'
if hasattr(sys, "gettotalrefcount"):
_header = '2P' + _header
_vheader = _header + 'P'
def calcobjsize(fmt):
return struct.calcsize(_header + fmt + '0P')
def calcvobjsize(fmt):
return struct.calcsize(_vheader + fmt + '0P')
_TPFLAGS_HAVE_GC = 1<<14
_TPFLAGS_HEAPTYPE = 1<<9
def check_sizeof(test, o, size):
result = sys.getsizeof(o)
# add GC header size
if (_testcapi and\
(type(o) == type) and (o.__flags__ & _TPFLAGS_HEAPTYPE) or\
((type(o) != type) and (type(o).__flags__ & _TPFLAGS_HAVE_GC))):
size += _testcapi.SIZEOF_PYGC_HEAD
msg = 'wrong size for %s: got %d, expected %d' \
% (type(o), result, size)
test.assertEqual(result, size, msg)
#=======================================================================
# Decorator for running a function in a different locale, correctly resetting
# it afterwards.
def run_with_locale(catstr, *locales):
def decorator(func):
def inner(*args, **kwds):
try:
import locale
category = getattr(locale, catstr)
orig_locale = locale.setlocale(category)
except AttributeError:
# if the test author gives us an invalid category string
raise
except:
# cannot retrieve original locale, so do nothing
locale = orig_locale = None
else:
for loc in locales:
try:
locale.setlocale(category, loc)
break
except:
pass
# now run the function, resetting the locale on exceptions
try:
return func(*args, **kwds)
finally:
if locale and orig_locale:
locale.setlocale(category, orig_locale)
inner.func_name = func.func_name
inner.__doc__ = func.__doc__
return inner
return decorator
#=======================================================================
# Big-memory-test support. Separate from 'resources' because memory use should be configurable.
# Some handy shorthands. Note that these are used for byte-limits as well
# as size-limits, in the various bigmem tests
_1M = 1024*1024
_1G = 1024 * _1M
_2G = 2 * _1G
_4G = 4 * _1G
MAX_Py_ssize_t = sys.maxsize
def set_memlimit(limit):
global max_memuse
global real_max_memuse
sizes = {
'k': 1024,
'm': _1M,
'g': _1G,
't': 1024*_1G,
}
m = re.match(r'(\d+(\.\d+)?) (K|M|G|T)b?$', limit,
re.IGNORECASE | re.VERBOSE)
if m is None:
raise ValueError('Invalid memory limit %r' % (limit,))
memlimit = int(float(m.group(1)) * sizes[m.group(3).lower()])
real_max_memuse = memlimit
if memlimit > MAX_Py_ssize_t:
memlimit = MAX_Py_ssize_t
if memlimit < _2G - 1:
raise ValueError('Memory limit %r too low to be useful' % (limit,))
max_memuse = memlimit
def bigmemtest(minsize, memuse, overhead=5*_1M):
"""Decorator for bigmem tests.
'minsize' is the minimum useful size for the test (in arbitrary,
test-interpreted units.) 'memuse' is the number of 'bytes per size' for
the test, or a good estimate of it. 'overhead' specifies fixed overhead,
independent of the testsize, and defaults to 5Mb.
The decorator tries to guess a good value for 'size' and passes it to
the decorated test function. If minsize * memuse is more than the
allowed memory use (as defined by max_memuse), the test is skipped.
Otherwise, minsize is adjusted upward to use up to max_memuse.
"""
def decorator(f):
def wrapper(self):
if not max_memuse:
# If max_memuse is 0 (the default),
# we still want to run the tests with size set to a few kb,
# to make sure they work. We still want to avoid using
# too much memory, though, but we do that noisily.
maxsize = 5147
self.failIf(maxsize * memuse + overhead > 20 * _1M)
else:
maxsize = int((max_memuse - overhead) / memuse)
if maxsize < minsize:
# Really ought to print 'test skipped' or something
if verbose:
sys.stderr.write("Skipping %s because of memory "
"constraint\n" % (f.__name__,))
return
# Try to keep some breathing room in memory use
maxsize = max(maxsize - 50 * _1M, minsize)
return f(self, maxsize)
wrapper.minsize = minsize
wrapper.memuse = memuse
wrapper.overhead = overhead
return wrapper
return decorator
def precisionbigmemtest(size, memuse, overhead=5*_1M, dry_run=True):
def decorator(f):
def wrapper(self):
if not real_max_memuse:
maxsize = 5147
else:
maxsize = size
if ((real_max_memuse or not dry_run)
and real_max_memuse < maxsize * memuse):
if verbose:
sys.stderr.write("Skipping %s because of memory "
"constraint\n" % (f.__name__,))
return
return f(self, maxsize)
wrapper.size = size
wrapper.memuse = memuse
wrapper.overhead = overhead
return wrapper
return decorator
def bigaddrspacetest(f):
"""Decorator for tests that fill the address space."""
def wrapper(self):
if max_memuse < MAX_Py_ssize_t:
if verbose:
sys.stderr.write("Skipping %s because of memory "
"constraint\n" % (f.__name__,))
else:
return f(self)
return wrapper
#=======================================================================
# unittest integration.
class BasicTestRunner:
def run(self, test):
result = unittest.TestResult()
test(result)
return result
def _id(obj):
return obj
def requires_resource(resource):
if is_resource_enabled(resource):
return _id
else:
return unittest.skip("resource {0!r} is not enabled".format(resource))
def cpython_only(test):
"""
Decorator for tests only applicable on CPython.
"""
return impl_detail(cpython=True)(test)
def impl_detail(msg=None, **guards):
if check_impl_detail(**guards):
return _id
if msg is None:
guardnames, default = _parse_guards(guards)
if default:
msg = "implementation detail not available on {0}"
else:
msg = "implementation detail specific to {0}"
guardnames = sorted(guardnames.keys())
msg = msg.format(' or '.join(guardnames))
return unittest.skip(msg)
def _parse_guards(guards):
# Returns a tuple ({platform_name: run_me}, default_value)
if not guards:
return ({'cpython': True}, False)
is_true = guards.values()[0]
assert guards.values() == [is_true] * len(guards) # all True or all False
return (guards, not is_true)
# Use the following check to guard CPython's implementation-specific tests --
# or to run them only on the implementation(s) guarded by the arguments.
def check_impl_detail(**guards):
"""This function returns True or False depending on the host platform.
Examples:
if check_impl_detail(): # only on CPython (default)
if check_impl_detail(jython=True): # only on Jython
if check_impl_detail(cpython=False): # everywhere except on CPython
"""
guards, default = _parse_guards(guards)
return guards.get(platform.python_implementation().lower(), default)
def _run_suite(suite):
"""Run tests from a unittest.TestSuite-derived class."""
if not junit_xml_dir:
# Splitting tests apart slightly changes the handling of the
# TestFailed message
return _run_suite(suite, testclass)
failed = False
for test in suite:
suite = unittest.TestSuite()
suite.addTest(test)
try:
_run_suite(suite, testclass)
except TestFailed, e:
if not failed:
failed = e
if failed:
raise failed
def _run_suite(suite, testclass=None):
if junit_xml_dir:
from junit_xml import JUnitXMLTestRunner
runner = JUnitXMLTestRunner(junit_xml_dir)
elif verbose:
runner = unittest.TextTestRunner(sys.stdout, verbosity=2)
else:
runner = BasicTestRunner()
result = runner.run(suite)
if not result.wasSuccessful():
if len(result.errors) == 1 and not result.failures:
err = result.errors[0][1]
elif len(result.failures) == 1 and not result.errors:
err = result.failures[0][1]
else:
err = "multiple errors occurred"
if not verbose:
err += "; run in verbose mode for details"
raise TestFailed(err)
def run_unittest(*classes):
"""Run tests from unittest.TestCase-derived classes."""
valid_types = (unittest.TestSuite, unittest.TestCase)
suite = unittest.TestSuite()
for cls in classes:
if isinstance(cls, str):
if cls in sys.modules:
suite.addTest(unittest.findTestCases(sys.modules[cls]))
else:
raise ValueError("str arguments must be keys in sys.modules")
elif isinstance(cls, valid_types):
suite.addTest(cls)
else:
suite.addTest(unittest.makeSuite(cls))
_run_suite(suite)
#=======================================================================
# Check for the presence of docstrings.
HAVE_DOCSTRINGS = (check_impl_detail(cpython=False) or
sys.platform == 'win32' or
sysconfig.get_config_var('WITH_DOC_STRINGS'))
requires_docstrings = unittest.skipUnless(HAVE_DOCSTRINGS,
"test requires docstrings")
#=======================================================================
# doctest driver.
def run_doctest(module, verbosity=None):
"""Run doctest on the given module. Return (#failures, #tests).
If optional argument verbosity is not specified (or is None), pass
test_support's belief about verbosity on to doctest. Else doctest's
usual behavior is used (it searches sys.argv for -v).
"""
import doctest
if verbosity is None:
verbosity = verbose
else:
verbosity = None
# Direct doctest output (normally just errors) to real stdout; doctest
# output shouldn't be compared by regrtest.
save_stdout = sys.stdout
sys.stdout = get_original_stdout()
try:
f, t = doctest.testmod(module, verbose=verbosity)
if f:
raise TestFailed("%d of %d doctests failed" % (f, t))
finally:
sys.stdout = save_stdout
if verbose:
print 'doctest (%s) ... %d tests with zero failures' % (module.__name__, t)
return f, t
#=======================================================================
# Threading support to prevent reporting refleaks when running regrtest.py -R
def threading_setup():
import threading
return len(threading._active), 0
def threading_cleanup(num_active, num_limbo):
import threading
import time
_MAX_COUNT = 10
count = 0
while len(threading._active) != num_active and count < _MAX_COUNT:
count += 1
time.sleep(0.1)
def reap_threads(func):
"""Use this function when threads are being used. This will
ensure that the threads are cleaned up even when the test fails.
If threading is unavailable this function does nothing.
"""
if not thread:
return func
@functools.wraps(func)
def decorator(*args):
key = threading_setup()
try:
return func(*args)
finally:
threading_cleanup(*key)
return decorator
def reap_children():
"""Use this function at the end of test_main() whenever sub-processes
are started. This will help ensure that no extra children (zombies)
stick around to hog resources and create problems when looking
for refleaks.
"""
# Reap all our dead child processes so we don't leave zombies around.
# These hog resources and might be causing some of the buildbots to die.
if hasattr(os, 'waitpid'):
any_process = -1
while True:
try:
# This will raise an exception on Windows. That's ok.
pid, status = os.waitpid(any_process, os.WNOHANG)
if pid == 0:
break
except:
break
@contextlib.contextmanager
def swap_attr(obj, attr, new_val):
"""Temporary swap out an attribute with a new object.
Usage:
with swap_attr(obj, "attr", 5):
...
This will set obj.attr to 5 for the duration of the with: block,
restoring the old value at the end of the block. If `attr` doesn't
exist on `obj`, it will be created and then deleted at the end of the
block.
"""
if hasattr(obj, attr):
real_val = getattr(obj, attr)
setattr(obj, attr, new_val)
try:
yield
finally:
setattr(obj, attr, real_val)
else:
setattr(obj, attr, new_val)
try:
yield
finally:
delattr(obj, attr)
def py3k_bytes(b):
"""Emulate the py3k bytes() constructor.
NOTE: This is only a best effort function.
"""
try:
# memoryview?
return b.tobytes()
except AttributeError:
try:
# iterable of ints?
return b"".join(chr(x) for x in b)
except TypeError:
return bytes(b)
def args_from_interpreter_flags():
"""Return a list of command-line arguments reproducing the current
settings in sys.flags."""
flag_opt_map = {
'bytes_warning': 'b',
'dont_write_bytecode': 'B',
'ignore_environment': 'E',
'no_user_site': 's',
'no_site': 'S',
'optimize': 'O',
'py3k_warning': '3',
'verbose': 'v',
}
args = []
for flag, opt in flag_opt_map.items():
v = getattr(sys.flags, flag)
if v > 0:
args.append('-' + opt * v)
return args
def strip_python_stderr(stderr):
"""Strip the stderr of a Python process from potential debug output
emitted by the interpreter.
This will typically be run on the result of the communicate() method
of a subprocess.Popen object.
"""
stderr = re.sub(br"\[\d+ refs\]\r?\n?$", b"", stderr).strip()
return stderr
def retry(exceptions, tries=6, delay=3, backoff=1.2):
# modified from https://wiki.python.org/moin/PythonDecoratorLibrary#Retry
def deco_retry(f):
def wrapper(*args, **kwds):
mtries, mdelay = tries, delay
while mtries > 1:
try:
return f(*args, **kwds)
except exceptions as e:
print "Got %s, retrying in %.2f seconds..." % (str(e), mdelay)
# FIXME resource cleanup continues to be an issue
# in terms of tests we use from CPython. This only
# represents a bandaid - useful as it might be -
# and it should be revisited.
gc_collect()
time.sleep(mdelay)
mtries -= 1
mdelay *= backoff
return f(*args, **kwds)
return wrapper
return deco_retry