Reverted decorators_trial.py and added command line docs.

* Reverted :mod:`IPython.testing.decorators_trial.py` and everything that
  uses it.
* Updated the command line usage information for ipcluster.

IPython/testing/decorators_trial.py

@@ -0,0 +1,132 b''
+# encoding: utf-8
+"""
+Testing related decorators for use with twisted.trial.
+
+The decorators in this files are designed to follow the same API as those
+in the decorators module (in this same directory).  But they can be used
+with twisted.trial
+"""
+
+#-----------------------------------------------------------------------------
+#  Copyright (C) 2008-2009  The IPython Development Team
+#
+#  Distributed under the terms of the BSD License.  The full license is in
+#  the file COPYING, distributed as part of this software.
+#-----------------------------------------------------------------------------
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+import os
+import sys
+
+from IPython.testing.decorators import make_label_dec
+
+#-----------------------------------------------------------------------------
+# Testing decorators
+#-----------------------------------------------------------------------------
+
+
+def skipif(skip_condition, msg=None):
+    """Create a decorator that marks a test function for skipping.
+
+    The is a decorator factory that returns a decorator that will 
+    conditionally skip a test based on the value of skip_condition.  The
+    skip_condition argument can either be a boolean or a callable that returns
+    a boolean.
+
+    Parameters
+    ----------
+    skip_condition : boolean or callable
+        If this evaluates to True, the test is skipped.
+    msg : str
+        The message to print if the test is skipped.
+
+    Returns
+    -------
+    decorator : function
+        The decorator function that can be applied to the test function.
+    """
+
+    def skip_decorator(f):
+
+        # Allow for both boolean or callable skip conditions.
+        if callable(skip_condition):
+            skip_val = lambda : skip_condition()
+        else:
+            skip_val = lambda : skip_condition
+
+        if msg is None:
+            out = 'Test skipped due to test condition.'
+        else: 
+            out = msg
+        final_msg = "Skipping test: %s. %s" % (f.__name__,out)
+
+        if skip_val():
+            f.skip = final_msg
+
+        return f
+    return skip_decorator
+
+
+def skip(msg=None):
+    """Create a decorator that marks a test function for skipping.
+
+    This is a decorator factory that returns a decorator that will cause
+    tests to be skipped.
+
+    Parameters
+    ----------
+    msg : str
+        Optional message to be added.
+
+    Returns
+    -------
+    decorator : function
+        Decorator, which, when applied to a function, sets the skip
+        attribute of the function causing `twisted.trial` to skip it.
+    """
+
+    return skipif(True,msg)
+
+
+def numpy_not_available():
+    """Can numpy be imported?  Returns true if numpy does NOT import.
+
+    This is used to make a decorator to skip tests that require numpy to be
+    available, but delay the 'import numpy' to test execution time.
+    """
+    try:
+        import numpy
+        np_not_avail = False
+    except ImportError:
+        np_not_avail = True
+
+    return np_not_avail
+
+#-----------------------------------------------------------------------------
+# Decorators for public use
+#-----------------------------------------------------------------------------
+
+# Decorators to skip certain tests on specific platforms.
+skip_win32 = skipif(sys.platform == 'win32',
+                    "This test does not run under Windows")
+skip_linux = skipif(sys.platform == 'linux2',
+                    "This test does not run under Linux")
+skip_osx = skipif(sys.platform == 'darwin',"This test does not run under OS X")
+
+# Decorators to skip tests if not on specific platforms.
+skip_if_not_win32 = skipif(sys.platform != 'win32',
+                           "This test only runs under Windows")
+skip_if_not_linux = skipif(sys.platform != 'linux2',
+                           "This test only runs under Linux")
+skip_if_not_osx = skipif(sys.platform != 'darwin',
+                         "This test only runs under OSX")
+
+# Other skip decorators
+skipif_not_numpy = skipif(numpy_not_available,"This test requires numpy")
+
+skipknownfailure = skip('This test is known to fail')
+
+

IPython/kernel/core/tests/test_redirectors.py

@@ -1,78 +1,79 b''
 # encoding: utf-8
 """
 Test the output capture at the OS level, using file descriptors.
 """
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is
 #  in the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Tell nose to skip this module
 __test__ = {}
 
 from cStringIO import StringIO
 import os
 import sys
 
 from twisted.trial import unittest
 
+from IPython.testing import decorators_trial as dec
+
 #-----------------------------------------------------------------------------
 # Tests
 #-----------------------------------------------------------------------------
 
 class TestRedirector(unittest.TestCase):
 
-    if sys.platform == 'win32':
-        skip = True
-    
+    @dec.skip_win32
     def test_redirector(self):
         """Checks that the redirector can be used to do synchronous capture.
         """
         from IPython.kernel.core.fd_redirector import FDRedirector
         r = FDRedirector()
         out = StringIO()
         try:
             r.start()
             for i in range(10):
                 os.system('echo %ic' % i)
                 print >>out, r.getvalue(),
                 print >>out, i
         except:
             r.stop()
             raise
         r.stop()
         result1 = out.getvalue()
         result2 = "".join("%ic\n%i\n" %(i, i) for i in range(10))
         self.assertEquals(result1, result2)
 
+    @dec.skip_win32
     def test_redirector_output_trap(self):
         """Check the greedy trapping behavior of the traps.
         
         This test check not only that the redirector_output_trap does
         trap the output, but also that it does it in a gready way, that
         is by calling the callback ASAP.
         """
         from IPython.kernel.core.redirector_output_trap import \
             RedirectorOutputTrap
         out = StringIO()
         trap = RedirectorOutputTrap(out.write, out.write)
         try:
             trap.set()
             for i in range(10):
                 os.system('echo %ic' % i)
                 print "%ip" % i
                 print >>out, i
         except:
             trap.unset()
             raise
         trap.unset()
         result1 = out.getvalue()
         result2 = "".join("%ic\n%ip\n%i\n" %(i, i, i) for i in range(10))
         self.assertEquals(result1, result2)
 

IPython/kernel/ipclusterapp.py

@@ -1,463 +1,499 b''
 #!/usr/bin/env python
 # encoding: utf-8
 """
 The ipcluster application.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 import logging
 import os
 import signal
 
 if os.name=='posix':
     from twisted.scripts._twistd_unix import daemonize
 
 from twisted.internet import reactor, defer
 from twisted.python import log, failure
 
 
 from IPython.external.argparse import ArgumentParser, SUPPRESS
 from IPython.utils.importstring import import_item
 from IPython.kernel.clusterdir import (
     ApplicationWithClusterDir, ClusterDirConfigLoader,
     ClusterDirError, PIDFileError
 )
 
 
 #-----------------------------------------------------------------------------
 # Module level variables
 #-----------------------------------------------------------------------------
 
 
 default_config_file_name = u'ipcluster_config.py'
 
 
 _description = """\
 Start an IPython cluster for parallel computing.\n\n
 
 An IPython cluster consists of 1 controller and 1 or more engines.
 This command automates the startup of these processes using a wide
 range of startup methods (SSH, local processes, PBS, mpiexec,
 Windows HPC Server 2008). To start a cluster with 4 engines on your
-local host simply do "ipcluster start -n 4". For more complex usage 
-you will typically do "ipcluster create -p mycluster", then edit
-configuration files, followed by "ipcluster start -p mycluster -n 4".
+local host simply do 'ipcluster start -n 4'. For more complex usage 
+you will typically do 'ipcluster create -p mycluster', then edit
+configuration files, followed by 'ipcluster start -p mycluster -n 4'.
 """
 
 
 # Exit codes for ipcluster
 
 # This will be the exit code if the ipcluster appears to be running because
 # a .pid file exists
 ALREADY_STARTED = 10
 
 
 # This will be the exit code if ipcluster stop is run, but there is not .pid
 # file to be found.
 ALREADY_STOPPED = 11
 
 
 #-----------------------------------------------------------------------------
 # Command line options
 #-----------------------------------------------------------------------------
 
 
 class IPClusterAppConfigLoader(ClusterDirConfigLoader):
 
     def _add_arguments(self):
         # Don't call ClusterDirConfigLoader._add_arguments as we don't want
         # its defaults on self.parser. Instead, we will put those on
         # default options on our subparsers.
         
         # This has all the common options that all subcommands use
         parent_parser1 = ArgumentParser(
             add_help=False,
             argument_default=SUPPRESS
         )
         self._add_ipython_dir(parent_parser1)
         self._add_log_level(parent_parser1)
 
         # This has all the common options that other subcommands use
         parent_parser2 = ArgumentParser(
             add_help=False,
             argument_default=SUPPRESS
         )
         self._add_cluster_profile(parent_parser2)
         self._add_cluster_dir(parent_parser2)
         self._add_work_dir(parent_parser2)
         paa = parent_parser2.add_argument
         paa('--log-to-file',
             action='store_true', dest='Global.log_to_file', 
             help='Log to a file in the log directory (default is stdout)')
 
         # Create the object used to create the subparsers.
         subparsers = self.parser.add_subparsers(
             dest='Global.subcommand',
             title='ipcluster subcommands',
             description=
             """ipcluster has a variety of subcommands. The general way of 
-            running ipcluster is 'ipcluster <cmd> [options]'""",
-            help="For more help, type 'ipcluster <cmd> -h'"
+            running ipcluster is 'ipcluster <cmd> [options]'. To get help
+            on a particular subcommand do 'ipcluster <cmd> -h'."""
+            # help="For more help, type 'ipcluster <cmd> -h'",
         )
 
         # The "list" subcommand parser
         parser_list = subparsers.add_parser(
             'list',
-            help='List all clusters in cwd and ipython_dir.',
             parents=[parent_parser1],
-            argument_default=SUPPRESS
+            argument_default=SUPPRESS,
+            help="List all clusters in cwd and ipython_dir.",
+            description=
+            """List all available clusters, by cluster directory, that can
+            be found in the current working directly or in the ipython
+            directory. Cluster directories are named using the convention
+            'cluster_<profile>'."""
         )
 
         # The "create" subcommand parser
         parser_create = subparsers.add_parser(
             'create',
-            help='Create a new cluster directory.',
             parents=[parent_parser1, parent_parser2],
-            argument_default=SUPPRESS
+            argument_default=SUPPRESS,
+            help="Create a new cluster directory.",
+            description=
+            """Create an ipython cluster directory by its profile name or 
+            cluster directory path. Cluster directories contain 
+            configuration, log and security related files and are named 
+            using the convention 'cluster_<profile>'. By default they are
+            located in your ipython directory. Once created, you will
+            probably need to edit the configuration files in the cluster
+            directory to configure your cluster. Most users will create a
+            cluster directory by profile name, 
+            'ipcluster create -p mycluster', which will put the directory
+            in '<ipython_dir>/cluster_mycluster'. 
+            """
         )
         paa = parser_create.add_argument
         paa('--reset-config',
             dest='Global.reset_config', action='store_true',
             help=
             """Recopy the default config files to the cluster directory.
             You will loose any modifications you have made to these files.""")
 
         # The "start" subcommand parser
         parser_start = subparsers.add_parser(
             'start',
-            help='Start a cluster.',
             parents=[parent_parser1, parent_parser2],
-            argument_default=SUPPRESS
+            argument_default=SUPPRESS,
+            help="Start a cluster.",
+            description=
+            """Start an ipython cluster by its profile name or cluster 
+            directory. Cluster directories contain configuration, log and
+            security related files and are named using the convention
+            'cluster_<profile>' and should be creating using the 'start'
+            subcommand of 'ipcluster'. If your cluster directory is in 
+            the cwd or the ipython directory, you can simply refer to it
+            using its profile name, 'ipcluster start -n 4 -p <profile>`,
+            otherwise use the '--cluster-dir' option.
+            """
         )
         paa = parser_start.add_argument
         paa('-n', '--number',
             type=int, dest='Global.n',
             help='The number of engines to start.',
             metavar='Global.n')
         paa('--clean-logs',
             dest='Global.clean_logs', action='store_true',
             help='Delete old log flies before starting.')
         paa('--no-clean-logs',
             dest='Global.clean_logs', action='store_false',
             help="Don't delete old log flies before starting.")
         paa('--daemon',
             dest='Global.daemonize', action='store_true',
             help='Daemonize the ipcluster program. This implies --log-to-file')
         paa('--no-daemon',
             dest='Global.daemonize', action='store_false',
             help="Dont't daemonize the ipcluster program.")
 
         # The "stop" subcommand parser
         parser_stop = subparsers.add_parser(
             'stop',
-            help='Stop a cluster.',
             parents=[parent_parser1, parent_parser2],
-            argument_default=SUPPRESS
+            argument_default=SUPPRESS,
+            help="Stop a running cluster.",
+            description=
+            """Stop a running ipython cluster by its profile name or cluster 
+            directory. Cluster directories are named using the convention
+            'cluster_<profile>'. If your cluster directory is in 
+            the cwd or the ipython directory, you can simply refer to it
+            using its profile name, 'ipcluster stop -p <profile>`, otherwise
+            use the '--cluster-dir' option.
+            """
         )
         paa = parser_stop.add_argument
         paa('--signal',
             dest='Global.signal', type=int,
             help="The signal number to use in stopping the cluster (default=2).",
             metavar="Global.signal")
 
 
 #-----------------------------------------------------------------------------
 # Main application
 #-----------------------------------------------------------------------------
 
 
 class IPClusterApp(ApplicationWithClusterDir):
 
     name = u'ipcluster'
     description = _description
     usage = None
     command_line_loader = IPClusterAppConfigLoader
     config_file_name = default_config_file_name
     default_log_level = logging.INFO
     auto_create_cluster_dir = False
 
     def create_default_config(self):
         super(IPClusterApp, self).create_default_config()
         self.default_config.Global.controller_launcher = \
             'IPython.kernel.launcher.LocalControllerLauncher'
         self.default_config.Global.engine_launcher = \
             'IPython.kernel.launcher.LocalEngineSetLauncher'
         self.default_config.Global.n = 2
         self.default_config.Global.reset_config = False
         self.default_config.Global.clean_logs = True
         self.default_config.Global.signal = 2
         self.default_config.Global.daemonize = False
 
     def find_resources(self):
         subcommand = self.command_line_config.Global.subcommand
         if subcommand=='list':
             self.list_cluster_dirs()
             # Exit immediately because there is nothing left to do.
             self.exit()
         elif subcommand=='create':
             self.auto_create_cluster_dir = True
             super(IPClusterApp, self).find_resources()
         elif subcommand=='start' or subcommand=='stop':
             self.auto_create_cluster_dir = True
             try:
                 super(IPClusterApp, self).find_resources()
             except ClusterDirError:
                 raise ClusterDirError(
                     "Could not find a cluster directory. A cluster dir must "
                     "be created before running 'ipcluster start'.  Do "
                     "'ipcluster create -h' or 'ipcluster list -h' for more "
                     "information about creating and listing cluster dirs."
                 )
 
     def list_cluster_dirs(self):
         # Find the search paths
         cluster_dir_paths = os.environ.get('IPCLUSTER_DIR_PATH','')
         if cluster_dir_paths:
             cluster_dir_paths = cluster_dir_paths.split(':')
         else:
             cluster_dir_paths = []
         try:
             ipython_dir = self.command_line_config.Global.ipython_dir
         except AttributeError:
             ipython_dir = self.default_config.Global.ipython_dir
         paths = [os.getcwd(), ipython_dir] + \
             cluster_dir_paths
         paths = list(set(paths))
 
         self.log.info('Searching for cluster dirs in paths: %r' % paths)
         for path in paths:
             files = os.listdir(path)
             for f in files:
                 full_path = os.path.join(path, f)
                 if os.path.isdir(full_path) and f.startswith('cluster_'):
                     profile = full_path.split('_')[-1]
                     start_cmd = 'ipcluster start -p %s -n 4' % profile
                     print start_cmd + " ==> " + full_path
 
     def pre_construct(self):
         # IPClusterApp.pre_construct() is where we cd to the working directory.
         super(IPClusterApp, self).pre_construct()
         config = self.master_config
         try:
             daemon = config.Global.daemonize
             if daemon:
                 config.Global.log_to_file = True
         except AttributeError:
             pass
 
     def construct(self):
         config = self.master_config
         subcmd = config.Global.subcommand
         reset = config.Global.reset_config
         if subcmd == 'list':
             return
         if subcmd == 'create':
             self.log.info('Copying default config files to cluster directory '
             '[overwrite=%r]' % (reset,))
             self.cluster_dir_obj.copy_all_config_files(overwrite=reset)
         if subcmd =='start':
             self.cluster_dir_obj.copy_all_config_files(overwrite=False)
             self.start_logging()
             reactor.callWhenRunning(self.start_launchers)
 
     def start_launchers(self):
         config = self.master_config
 
         # Create the launchers. In both bases, we set the work_dir of
         # the launcher to the cluster_dir. This is where the launcher's
         # subprocesses will be launched. It is not where the controller
         # and engine will be launched.
         el_class = import_item(config.Global.engine_launcher)
         self.engine_launcher = el_class(
             work_dir=self.cluster_dir, config=config
         )
         cl_class = import_item(config.Global.controller_launcher)
         self.controller_launcher = cl_class(
             work_dir=self.cluster_dir, config=config
         )
 
         # Setup signals
         signal.signal(signal.SIGINT, self.sigint_handler)
 
         # Setup the observing of stopping. If the controller dies, shut
         # everything down as that will be completely fatal for the engines.
         d1 = self.controller_launcher.observe_stop()
         d1.addCallback(self.stop_launchers)
         # But, we don't monitor the stopping of engines. An engine dying
         # is just fine and in principle a user could start a new engine.
         # Also, if we did monitor engine stopping, it is difficult to
         # know what to do when only some engines die. Currently, the
         # observing of engine stopping is inconsistent. Some launchers
         # might trigger on a single engine stopping, other wait until
         # all stop.  TODO: think more about how to handle this.
         
         # Start the controller and engines
         self._stopping = False  # Make sure stop_launchers is not called 2x.
         d = self.start_controller()
         d.addCallback(self.start_engines)
         d.addCallback(self.startup_message)
         # If the controller or engines fail to start, stop everything
         d.addErrback(self.stop_launchers)
         return d
 
     def startup_message(self, r=None):
         log.msg("IPython cluster: started")
         return r
         
     def start_controller(self, r=None):
         # log.msg("In start_controller")
         config = self.master_config
         d = self.controller_launcher.start(
             cluster_dir=config.Global.cluster_dir
         )
         return d
             
     def start_engines(self, r=None):
         # log.msg("In start_engines")
         config = self.master_config
         d = self.engine_launcher.start(
             config.Global.n,
             cluster_dir=config.Global.cluster_dir
         )
         return d
 
     def stop_controller(self, r=None):
         # log.msg("In stop_controller")
         if self.controller_launcher.running:
             d = self.controller_launcher.stop()
             d.addErrback(self.log_err)
             return d
         else:
             return defer.succeed(None)
 
     def stop_engines(self, r=None):
         # log.msg("In stop_engines")
         if self.engine_launcher.running:
             d = self.engine_launcher.stop()
             d.addErrback(self.log_err)
             return d
         else:
             return defer.succeed(None)
 
     def log_err(self, f):
         log.msg(f.getTraceback())
         return None
         
     def stop_launchers(self, r=None):
         if not self._stopping:
             self._stopping = True
             if isinstance(r, failure.Failure):
                 log.msg('Unexpected error in ipcluster:')
                 log.msg(r.getTraceback())
             log.msg("IPython cluster: stopping")
             # These return deferreds. We are not doing anything with them
             # but we are holding refs to them as a reminder that they 
             # do return deferreds.
             d1 = self.stop_engines()
             d2 = self.stop_controller()
             # Wait a few seconds to let things shut down.
             reactor.callLater(4.0, reactor.stop)
 
     def sigint_handler(self, signum, frame):
         self.stop_launchers()
         
     def start_logging(self):
         # Remove old log files of the controller and engine
         if self.master_config.Global.clean_logs:
             log_dir = self.master_config.Global.log_dir
             for f in os.listdir(log_dir):
                 if f.startswith('ipengine' + '-'):
                     if f.endswith('.log') or f.endswith('.out') or f.endswith('.err'):
                         os.remove(os.path.join(log_dir, f))
                 if f.startswith('ipcontroller' + '-'):
                     if f.endswith('.log') or f.endswith('.out') or f.endswith('.err'):
                         os.remove(os.path.join(log_dir, f))
         # This will remote old log files for ipcluster itself
         super(IPClusterApp, self).start_logging()
 
     def start_app(self):
         """Start the application, depending on what subcommand is used."""
         subcmd = self.master_config.Global.subcommand
         if subcmd=='create' or subcmd=='list':
             return
         elif subcmd=='start':
             self.start_app_start()
         elif subcmd=='stop':
             self.start_app_stop()
 
     def start_app_start(self):
         """Start the app for the start subcommand."""
         config = self.master_config
         # First see if the cluster is already running
         try:
             pid = self.get_pid_from_file()
         except PIDFileError:
             pass
         else:
             self.log.critical(
                 'Cluster is already running with [pid=%s]. '
                 'use "ipcluster stop" to stop the cluster.' % pid
             )
             # Here I exit with a unusual exit status that other processes
             # can watch for to learn how I existed.
             self.exit(ALREADY_STARTED)
 
         # Now log and daemonize
         self.log.info(
             'Starting ipcluster with [daemon=%r]' % config.Global.daemonize
         )
         # TODO: Get daemonize working on Windows or as a Windows Server.
         if config.Global.daemonize:
             if os.name=='posix':
                 daemonize()
 
         # Now write the new pid file AFTER our new forked pid is active.
         self.write_pid_file()
         reactor.addSystemEventTrigger('during','shutdown', self.remove_pid_file)
         reactor.run()
 
     def start_app_stop(self):
         """Start the app for the stop subcommand."""
         config = self.master_config
         try:
             pid = self.get_pid_from_file()
         except PIDFileError:
             self.log.critical(
                 'Problem reading pid file, cluster is probably not running.'
             )
             # Here I exit with a unusual exit status that other processes
             # can watch for to learn how I existed.
             self.exit(ALREADY_STOPPED)
         else:
             if os.name=='posix':
                 sig = config.Global.signal
                 self.log.info(
                     "Stopping cluster [pid=%r] with [signal=%r]" % (pid, sig)
                 )
                 os.kill(pid, sig)
             elif os.name=='nt':
                 # As of right now, we don't support daemonize on Windows, so
                 # stop will not do anything. Minimally, it should clean up the
                 # old .pid files.
                 self.remove_pid_file()
 
 
 def launch_new_instance():
     """Create and run the IPython cluster."""
     app = IPClusterApp()
     app.start()
 
 
 if __name__ == '__main__':
     launch_new_instance()
 

IPython/testing/tests/test_decorators_trial.py

@@ -1,57 +1,52 b''
 # encoding: utf-8
 """
-Tests for decorators.py compatibility with Twisted.trial
+Tests for decorators_trial.py
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
-# Tell nose to skip this module, since this is for twisted only
+# Tell nose to skip this module
 __test__ = {}
 
 import os
 import sys
 
 from twisted.trial import unittest
-import IPython.testing.decorators as dec
+import IPython.testing.decorators_trial as dec
 
 #-----------------------------------------------------------------------------
 # Tests
 #-----------------------------------------------------------------------------
 
-# Note: this code is identical to that in test_decorators, but that one uses
-# stdlib unittest, not the one from twisted, which we are using here. While
-# somewhat redundant, we want to check both with the stdlib and with twisted,
-# so the duplication is OK.
-
 class TestDecoratorsTrial(unittest.TestCase):
     
     @dec.skip()
     def test_deliberately_broken(self):
         """A deliberately broken test - we want to skip this one."""
         1/0
 
     @dec.skip('Testing the skip decorator')
     def test_deliberately_broken2(self):
         """Another deliberately broken test - we want to skip this one."""
         1/0
 
     @dec.skip_linux
     def test_linux(self):
         self.assertNotEquals(sys.platform,'linux2',"This test can't run under linux")
 
     @dec.skip_win32
     def test_win32(self):
         self.assertNotEquals(sys.platform,'win32',"This test can't run under windows")
 
     @dec.skip_osx
     def test_osx(self):
         self.assertNotEquals(sys.platform,'darwin',"This test can't run under osx")