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			1030 lines
		
	
	
	
		
			36 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			1030 lines
		
	
	
	
		
			36 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
"""Supporting definitions for the Python regression tests."""
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if __name__ != 'test.test_support':
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    raise ImportError('test_support must be imported from the test package')
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import contextlib
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import errno
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import functools
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import gc
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import socket
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import sys
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import os
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import platform
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import shutil
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import warnings
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import unittest
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import importlib
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import UserDict
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__all__ = ["Error", "TestFailed", "ResourceDenied", "import_module",
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           "verbose", "use_resources", "max_memuse", "record_original_stdout",
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           "get_original_stdout", "unload", "unlink", "rmtree", "forget",
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           "is_resource_enabled", "requires", "find_unused_port", "bind_port",
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           "fcmp", "have_unicode", "is_jython", "TESTFN", "HOST", "FUZZ",
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           "findfile", "verify", "vereq", "sortdict", "check_syntax_error",
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           "open_urlresource", "check_warnings", "CleanImport",
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           "EnvironmentVarGuard", "captured_output",
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           "captured_stdout", "TransientResource", "transient_internet",
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           "run_with_locale", "set_memlimit", "bigmemtest", "bigaddrspacetest",
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           "BasicTestRunner", "run_unittest", "run_doctest", "threading_setup",
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           "threading_cleanup", "reap_children", "cpython_only",
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           "check_impl_detail", "get_attribute", "py3k_bytes"]
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class Error(Exception):
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    """Base class for regression test exceptions."""
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class TestFailed(Error):
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    """Test failed."""
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class ResourceDenied(unittest.SkipTest):
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    """Test skipped because it requested a disallowed resource.
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    This is raised when a test calls requires() for a resource that
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    has not be enabled.  It is used to distinguish between expected
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    and unexpected skips.
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    """
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@contextlib.contextmanager
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def _ignore_deprecated_imports(ignore=True):
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    """Context manager to suppress package and module deprecation
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    warnings when importing them.
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    If ignore is False, this context manager has no effect."""
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    if ignore:
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        with warnings.catch_warnings():
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            warnings.filterwarnings("ignore", ".+ (module|package)",
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                                    DeprecationWarning)
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            yield
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    else:
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        yield
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def import_module(name, deprecated=False):
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    """Import and return the module to be tested, raising SkipTest if
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    it is not available.
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    If deprecated is True, any module or package deprecation messages
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    will be suppressed."""
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    with _ignore_deprecated_imports(deprecated):
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        try:
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            return importlib.import_module(name)
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        except ImportError, msg:
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            raise unittest.SkipTest(str(msg))
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def _save_and_remove_module(name, orig_modules):
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    """Helper function to save and remove a module from sys.modules
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       Return value is True if the module was in sys.modules and
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       False otherwise."""
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    saved = True
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    try:
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        orig_modules[name] = sys.modules[name]
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    except KeyError:
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        saved = False
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    else:
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        del sys.modules[name]
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    return saved
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def _save_and_block_module(name, orig_modules):
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    """Helper function to save and block a module in sys.modules
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       Return value is True if the module was in sys.modules and
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       False otherwise."""
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    saved = True
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    try:
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        orig_modules[name] = sys.modules[name]
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    except KeyError:
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        saved = False
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    sys.modules[name] = 0
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    return saved
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def import_fresh_module(name, fresh=(), blocked=(), deprecated=False):
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    """Imports and returns a module, deliberately bypassing the sys.modules cache
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    and importing a fresh copy of the module. Once the import is complete,
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    the sys.modules cache is restored to its original state.
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    Modules named in fresh are also imported anew if needed by the import.
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    Importing of modules named in blocked is prevented while the fresh import
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    takes place.
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    If deprecated is True, any module or package deprecation messages
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    will be suppressed."""
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    # NOTE: test_heapq and test_warnings include extra sanity checks to make
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    # sure that this utility function is working as expected
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    with _ignore_deprecated_imports(deprecated):
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        # Keep track of modules saved for later restoration as well
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        # as those which just need a blocking entry removed
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        orig_modules = {}
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        names_to_remove = []
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        _save_and_remove_module(name, orig_modules)
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        try:
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            for fresh_name in fresh:
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                _save_and_remove_module(fresh_name, orig_modules)
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            for blocked_name in blocked:
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                if not _save_and_block_module(blocked_name, orig_modules):
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                    names_to_remove.append(blocked_name)
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            fresh_module = importlib.import_module(name)
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        finally:
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            for orig_name, module in orig_modules.items():
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                sys.modules[orig_name] = module
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            for name_to_remove in names_to_remove:
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                del sys.modules[name_to_remove]
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        return fresh_module
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def get_attribute(obj, name):
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    """Get an attribute, raising SkipTest if AttributeError is raised."""
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    try:
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        attribute = getattr(obj, name)
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    except AttributeError:
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        raise unittest.SkipTest("module %s has no attribute %s" % (
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            obj.__name__, name))
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    else:
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        return attribute
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verbose = 1              # Flag set to 0 by regrtest.py
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use_resources = None     # Flag set to [] by regrtest.py
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max_memuse = 0           # Disable bigmem tests (they will still be run with
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                         # small sizes, to make sure they work.)
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real_max_memuse = 0
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# _original_stdout is meant to hold stdout at the time regrtest began.
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# This may be "the real" stdout, or IDLE's emulation of stdout, or whatever.
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# The point is to have some flavor of stdout the user can actually see.
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_original_stdout = None
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def record_original_stdout(stdout):
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    global _original_stdout
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    _original_stdout = stdout
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def get_original_stdout():
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    return _original_stdout or sys.stdout
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def unload(name):
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    try:
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        del sys.modules[name]
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    except KeyError:
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        pass
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def unlink(filename):
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    try:
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        os.unlink(filename)
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    except OSError:
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        pass
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def rmtree(path):
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    try:
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        shutil.rmtree(path)
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    except OSError, e:
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        # Unix returns ENOENT, Windows returns ESRCH.
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        if e.errno not in (errno.ENOENT, errno.ESRCH):
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            raise
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def forget(modname):
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    '''"Forget" a module was ever imported by removing it from sys.modules and
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    deleting any .pyc and .pyo files.'''
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    unload(modname)
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    for dirname in sys.path:
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        unlink(os.path.join(dirname, modname + os.extsep + 'pyc'))
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        # Deleting the .pyo file cannot be within the 'try' for the .pyc since
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        # the chance exists that there is no .pyc (and thus the 'try' statement
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        # is exited) but there is a .pyo file.
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        unlink(os.path.join(dirname, modname + os.extsep + 'pyo'))
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def is_resource_enabled(resource):
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    """Test whether a resource is enabled.  Known resources are set by
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    regrtest.py."""
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    return use_resources is not None and resource in use_resources
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def requires(resource, msg=None):
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    """Raise ResourceDenied if the specified resource is not available.
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    If the caller's module is __main__ then automatically return True.  The
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    possibility of False being returned occurs when regrtest.py is executing."""
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    # see if the caller's module is __main__ - if so, treat as if
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    # the resource was set
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    if sys._getframe(1).f_globals.get("__name__") == "__main__":
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        return
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    if not is_resource_enabled(resource):
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        if msg is None:
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            msg = "Use of the `%s' resource not enabled" % resource
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        raise ResourceDenied(msg)
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HOST = 'localhost'
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def find_unused_port(family=socket.AF_INET, socktype=socket.SOCK_STREAM):
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    """Returns an unused port that should be suitable for binding.  This is
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    achieved by creating a temporary socket with the same family and type as
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    the 'sock' parameter (default is AF_INET, SOCK_STREAM), and binding it to
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    the specified host address (defaults to 0.0.0.0) with the port set to 0,
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    eliciting an unused ephemeral port from the OS.  The temporary socket is
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    then closed and deleted, and the ephemeral port is returned.
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    Either this method or bind_port() should be used for any tests where a
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    server socket needs to be bound to a particular port for the duration of
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    the test.  Which one to use depends on whether the calling code is creating
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    a python socket, or if an unused port needs to be provided in a constructor
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    or passed to an external program (i.e. the -accept argument to openssl's
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    s_server mode).  Always prefer bind_port() over find_unused_port() where
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    possible.  Hard coded ports should *NEVER* be used.  As soon as a server
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    socket is bound to a hard coded port, the ability to run multiple instances
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    of the test simultaneously on the same host is compromised, which makes the
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    test a ticking time bomb in a buildbot environment. On Unix buildbots, this
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    may simply manifest as a failed test, which can be recovered from without
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    intervention in most cases, but on Windows, the entire python process can
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    completely and utterly wedge, requiring someone to log in to the buildbot
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    and manually kill the affected process.
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    (This is easy to reproduce on Windows, unfortunately, and can be traced to
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    the SO_REUSEADDR socket option having different semantics on Windows versus
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    Unix/Linux.  On Unix, you can't have two AF_INET SOCK_STREAM sockets bind,
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    listen and then accept connections on identical host/ports.  An EADDRINUSE
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    socket.error will be raised at some point (depending on the platform and
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    the order bind and listen were called on each socket).
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    However, on Windows, if SO_REUSEADDR is set on the sockets, no EADDRINUSE
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    will ever be raised when attempting to bind two identical host/ports. When
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    accept() is called on each socket, the second caller's process will steal
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    the port from the first caller, leaving them both in an awkwardly wedged
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    state where they'll no longer respond to any signals or graceful kills, and
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    must be forcibly killed via OpenProcess()/TerminateProcess().
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    The solution on Windows is to use the SO_EXCLUSIVEADDRUSE socket option
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    instead of SO_REUSEADDR, which effectively affords the same semantics as
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    SO_REUSEADDR on Unix.  Given the propensity of Unix developers in the Open
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    Source world compared to Windows ones, this is a common mistake.  A quick
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    look over OpenSSL's 0.9.8g source shows that they use SO_REUSEADDR when
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    openssl.exe is called with the 's_server' option, for example. See
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    http://bugs.python.org/issue2550 for more info.  The following site also
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    has a very thorough description about the implications of both REUSEADDR
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    and EXCLUSIVEADDRUSE on Windows:
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    http://msdn2.microsoft.com/en-us/library/ms740621(VS.85).aspx)
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    XXX: although this approach is a vast improvement on previous attempts to
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    elicit unused ports, it rests heavily on the assumption that the ephemeral
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    port returned to us by the OS won't immediately be dished back out to some
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    other process when we close and delete our temporary socket but before our
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    calling code has a chance to bind the returned port.  We can deal with this
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    issue if/when we come across it."""
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    tempsock = socket.socket(family, socktype)
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    port = bind_port(tempsock)
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    tempsock.close()
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    del tempsock
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    return port
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def bind_port(sock, host=HOST):
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    """Bind the socket to a free port and return the port number.  Relies on
 | 
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    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
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    is AF_INET and sock.type is SOCK_STREAM, *and* the socket has SO_REUSEADDR
 | 
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    or SO_REUSEPORT set on it.  Tests should *never* set these socket options
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    for TCP/IP sockets.  The only case for setting these options is testing
 | 
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    multicasting via multiple UDP sockets.
 | 
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 | 
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    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
 | 
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    from bind()'ing to our host/port for the duration of the test.
 | 
						|
    """
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    if sock.family == socket.AF_INET and sock.type == socket.SOCK_STREAM:
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						|
        if hasattr(socket, 'SO_REUSEADDR'):
 | 
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            if sock.getsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR) == 1:
 | 
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                raise TestFailed("tests should never set the SO_REUSEADDR "   \
 | 
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                                 "socket option on TCP/IP sockets!")
 | 
						|
        if hasattr(socket, 'SO_REUSEPORT'):
 | 
						|
            if sock.getsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT) == 1:
 | 
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                raise TestFailed("tests should never set the SO_REUSEPORT "   \
 | 
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                                 "socket option on TCP/IP sockets!")
 | 
						|
        if hasattr(socket, 'SO_EXCLUSIVEADDRUSE'):
 | 
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            sock.setsockopt(socket.SOL_SOCKET, socket.SO_EXCLUSIVEADDRUSE, 1)
 | 
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 | 
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    sock.bind((host, 0))
 | 
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    port = sock.getsockname()[1]
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    return port
 | 
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 | 
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FUZZ = 1e-6
 | 
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 | 
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def fcmp(x, y): # fuzzy comparison function
 | 
						|
    if isinstance(x, float) or isinstance(y, float):
 | 
						|
        try:
 | 
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            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))):
 | 
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            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')
 | 
						|
 | 
						|
# 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
 | 
						|
 | 
						|
# Disambiguate TESTFN for parallel testing, while letting it remain a valid
 | 
						|
# module name.
 | 
						|
TESTFN = "{0}_{1}_tmp".format(TESTFN, os.getpid())
 | 
						|
 | 
						|
# 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
 | 
						|
 | 
						|
def findfile(file, here=__file__):
 | 
						|
    """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
 | 
						|
    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):
 | 
						|
    testcase.assertRaises(SyntaxError, compile, statement,
 | 
						|
                          '<test string>', 'exec')
 | 
						|
 | 
						|
def open_urlresource(url):
 | 
						|
    import urlparse, urllib2
 | 
						|
 | 
						|
    requires('urlfetch')
 | 
						|
    filename = urlparse.urlparse(url)[2].split('/')[-1] # '/': it's URL!
 | 
						|
 | 
						|
    fn = os.path.join(os.path.dirname(__file__), "data", filename)
 | 
						|
    if os.path.exists(fn):
 | 
						|
        return open(fn)
 | 
						|
 | 
						|
    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()
 | 
						|
    return open(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
 | 
						|
 | 
						|
    def __getattr__(self, attr):
 | 
						|
        if self.warnings:
 | 
						|
            return getattr(self.warnings[-1], attr)
 | 
						|
        elif attr in warnings.WarningMessage._WARNING_DETAILS:
 | 
						|
            return None
 | 
						|
        raise AttributeError("%r has no attribute %r" % (self, attr))
 | 
						|
 | 
						|
    def reset(self):
 | 
						|
        del self.warnings[:]
 | 
						|
 | 
						|
@contextlib.contextmanager
 | 
						|
def check_warnings():
 | 
						|
    with warnings.catch_warnings(record=True) as w:
 | 
						|
        yield WarningsRecorder(w)
 | 
						|
 | 
						|
 | 
						|
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 DirsOnSysPath(object):
 | 
						|
    """Context manager to temporarily add directories to sys.path.
 | 
						|
 | 
						|
    This makes a copy of sys.path, appends any directories given
 | 
						|
    as positional arguments, then reverts sys.path to the copied
 | 
						|
    settings when the context ends.
 | 
						|
 | 
						|
    Note that *all* sys.path modifications in the body of the
 | 
						|
    context manager, including replacement of the object,
 | 
						|
    will be reverted at the end of the block.
 | 
						|
    """
 | 
						|
 | 
						|
    def __init__(self, *paths):
 | 
						|
        self.original_value = sys.path[:]
 | 
						|
        self.original_object = sys.path
 | 
						|
        sys.path.extend(paths)
 | 
						|
 | 
						|
    def __enter__(self):
 | 
						|
        return self
 | 
						|
 | 
						|
    def __exit__(self, *ignore_exc):
 | 
						|
        sys.path = self.original_object
 | 
						|
        sys.path[:] = self.original_value
 | 
						|
 | 
						|
 | 
						|
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():
 | 
						|
    """Return a context manager that raises ResourceDenied when various issues
 | 
						|
    with the Internet connection manifest themselves as exceptions."""
 | 
						|
    time_out = TransientResource(IOError, errno=errno.ETIMEDOUT)
 | 
						|
    socket_peer_reset = TransientResource(socket.error, errno=errno.ECONNRESET)
 | 
						|
    ioerror_peer_reset = TransientResource(IOError, errno=errno.ECONNRESET)
 | 
						|
    with time_out, socket_peer_reset, ioerror_peer_reset:
 | 
						|
        yield
 | 
						|
 | 
						|
 | 
						|
@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_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()
 | 
						|
    gc.collect()
 | 
						|
    gc.collect()
 | 
						|
 | 
						|
 | 
						|
#=======================================================================
 | 
						|
# 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):
 | 
						|
    import re
 | 
						|
    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.assertFalse(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):
 | 
						|
    def decorator(f):
 | 
						|
        def wrapper(self):
 | 
						|
            if not real_max_memuse:
 | 
						|
                maxsize = 5147
 | 
						|
            else:
 | 
						|
                maxsize = size
 | 
						|
 | 
						|
                if real_max_memuse 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 resource_is_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 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)
 | 
						|
 | 
						|
 | 
						|
#=======================================================================
 | 
						|
# 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
 | 
						|
 | 
						|
# NOTE: we use thread._count() rather than threading.enumerate() (or the
 | 
						|
# moral equivalent thereof) because a threading.Thread object is still alive
 | 
						|
# until its __bootstrap() method has returned, even after it has been
 | 
						|
# unregistered from the threading module.
 | 
						|
# thread._count(), on the other hand, only gets decremented *after* the
 | 
						|
# __bootstrap() method has returned, which gives us reliable reference counts
 | 
						|
# at the end of a test run.
 | 
						|
 | 
						|
def threading_setup():
 | 
						|
    import thread
 | 
						|
    return thread._count(),
 | 
						|
 | 
						|
def threading_cleanup(nb_threads):
 | 
						|
    import thread
 | 
						|
    import time
 | 
						|
 | 
						|
    _MAX_COUNT = 10
 | 
						|
    for count in range(_MAX_COUNT):
 | 
						|
        n = thread._count()
 | 
						|
        if n == nb_threads:
 | 
						|
            break
 | 
						|
        time.sleep(0.1)
 | 
						|
    # XXX print a warning in case of failure?
 | 
						|
 | 
						|
def reap_threads(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
 | 
						|
 | 
						|
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)
 |