Don't show subprocess output if there isn't any

IPython/testing/iptest.py

@@ -1,520 +1,524
 # -*- coding: utf-8 -*-
 """IPython Test Suite Runner.
 
 This module provides a main entry point to a user script to test IPython
 itself from the command line. There are two ways of running this script:
 
 1. With the syntax `iptest all`.  This runs our entire test suite by
    calling this script (with different arguments) recursively.  This
    causes modules and package to be tested in different processes, using nose
    or trial where appropriate.
 2. With the regular nose syntax, like `iptest -vvs IPython`.  In this form
    the script simply calls nose, but with special command line flags and
    plugins loaded.
 
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2009-2011  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
 #-----------------------------------------------------------------------------
 from __future__ import print_function
 
 # Stdlib
 import glob
 from io import BytesIO
 import os
 import os.path as path
 from select import select
 import sys
 from threading import Thread, Lock, Event
 import warnings
 
 # Now, proceed to import nose itself
 import nose.plugins.builtin
 from nose.plugins.xunit import Xunit
 from nose import SkipTest
 from nose.core import TestProgram
 from nose.plugins import Plugin
 from nose.util import safe_str
 
 # Our own imports
 from IPython.utils.importstring import import_item
 from IPython.testing.plugin.ipdoctest import IPythonDoctest
 from IPython.external.decorators import KnownFailure, knownfailureif
 
 pjoin = path.join
 
 
 #-----------------------------------------------------------------------------
 # Globals
 #-----------------------------------------------------------------------------
 
 
 #-----------------------------------------------------------------------------
 # Warnings control
 #-----------------------------------------------------------------------------
 
 # Twisted generates annoying warnings with Python 2.6, as will do other code
 # that imports 'sets' as of today
 warnings.filterwarnings('ignore', 'the sets module is deprecated',
                         DeprecationWarning )
 
 # This one also comes from Twisted
 warnings.filterwarnings('ignore', 'the sha module is deprecated',
                         DeprecationWarning)
 
 # Wx on Fedora11 spits these out
 warnings.filterwarnings('ignore', 'wxPython/wxWidgets release number mismatch',
                         UserWarning)
 
 # ------------------------------------------------------------------------------
 # Monkeypatch Xunit to count known failures as skipped.
 # ------------------------------------------------------------------------------
 def monkeypatch_xunit():
     try:
         knownfailureif(True)(lambda: None)()
     except Exception as e:
         KnownFailureTest = type(e)
 
     def addError(self, test, err, capt=None):
         if issubclass(err[0], KnownFailureTest):
             err = (SkipTest,) + err[1:]
         return self.orig_addError(test, err, capt)
 
     Xunit.orig_addError = Xunit.addError
     Xunit.addError = addError
 
 #-----------------------------------------------------------------------------
 # Check which dependencies are installed and greater than minimum version.
 #-----------------------------------------------------------------------------
 def extract_version(mod):
     return mod.__version__
 
 def test_for(item, min_version=None, callback=extract_version):
     """Test to see if item is importable, and optionally check against a minimum
     version.
 
     If min_version is given, the default behavior is to check against the
     `__version__` attribute of the item, but specifying `callback` allows you to
     extract the value you are interested in. e.g::
 
         In [1]: import sys
 
         In [2]: from IPython.testing.iptest import test_for
 
         In [3]: test_for('sys', (2,6), callback=lambda sys: sys.version_info)
         Out[3]: True
 
     """
     try:
         check = import_item(item)
     except (ImportError, RuntimeError):
         # GTK reports Runtime error if it can't be initialized even if it's
         # importable.
         return False
     else:
         if min_version:
             if callback:
                 # extra processing step to get version to compare
                 check = callback(check)
 
             return check >= min_version
         else:
             return True
 
 # Global dict where we can store information on what we have and what we don't
 # have available at test run time
 have = {}
 
 have['curses'] = test_for('_curses')
 have['matplotlib'] = test_for('matplotlib')
 have['numpy'] = test_for('numpy')
 have['pexpect'] = test_for('IPython.external.pexpect')
 have['pymongo'] = test_for('pymongo')
 have['pygments'] = test_for('pygments')
 have['qt'] = test_for('IPython.external.qt')
 have['rpy2'] = test_for('rpy2')
 have['sqlite3'] = test_for('sqlite3')
 have['cython'] = test_for('Cython')
 have['oct2py'] = test_for('oct2py')
 have['tornado'] = test_for('tornado.version_info', (2,1,0), callback=None)
 have['jinja2'] = test_for('jinja2')
 have['wx'] = test_for('wx')
 have['wx.aui'] = test_for('wx.aui')
 have['azure'] = test_for('azure')
 have['sphinx'] = test_for('sphinx')
 
 min_zmq = (2,1,11)
 
 have['zmq'] = test_for('zmq.pyzmq_version_info', min_zmq, callback=lambda x: x())
 
 #-----------------------------------------------------------------------------
 # Test suite definitions
 #-----------------------------------------------------------------------------
 
 test_group_names = ['parallel', 'kernel', 'kernel.inprocess', 'config', 'core',
                     'extensions', 'lib', 'terminal', 'testing', 'utils',
                     'nbformat', 'qt', 'html', 'nbconvert'
                    ]
 
 class TestSection(object):
     def __init__(self, name, includes):
         self.name = name
         self.includes = includes
         self.excludes = []
         self.dependencies = []
         self.enabled = True
     
     def exclude(self, module):
         if not module.startswith('IPython'):
             module = self.includes[0] + "." + module
         self.excludes.append(module.replace('.', os.sep))
     
     def requires(self, *packages):
         self.dependencies.extend(packages)
     
     @property
     def will_run(self):
         return self.enabled and all(have[p] for p in self.dependencies)
 
 # Name -> (include, exclude, dependencies_met)
 test_sections = {n:TestSection(n, ['IPython.%s' % n]) for n in test_group_names}
 
 # Exclusions and dependencies
 # ---------------------------
 
 # core:
 sec = test_sections['core']
 if not have['sqlite3']:
     sec.exclude('tests.test_history')
     sec.exclude('history')
 if not have['matplotlib']:
     sec.exclude('pylabtools'),
     sec.exclude('tests.test_pylabtools')
 
 # lib:
 sec = test_sections['lib']
 if not have['wx']:
     sec.exclude('inputhookwx')
 if not have['pexpect']:
     sec.exclude('irunner')
     sec.exclude('tests.test_irunner')
 if not have['zmq']:
     sec.exclude('kernel')
 # We do this unconditionally, so that the test suite doesn't import
 # gtk, changing the default encoding and masking some unicode bugs.
 sec.exclude('inputhookgtk')
 # Testing inputhook will need a lot of thought, to figure out
 # how to have tests that don't lock up with the gui event
 # loops in the picture
 sec.exclude('inputhook')
 
 # testing:
 sec = test_sections['testing']
 # This guy is probably attic material
 sec.exclude('mkdoctests')
 # These have to be skipped on win32 because they use echo, rm, cd, etc.
 # See ticket https://github.com/ipython/ipython/issues/87
 if sys.platform == 'win32':
     sec.exclude('plugin.test_exampleip')
     sec.exclude('plugin.dtexample')
 
 # terminal:
 if (not have['pexpect']) or (not have['zmq']):
     test_sections['terminal'].exclude('console')
 
 # parallel
 sec = test_sections['parallel']
 sec.requires('zmq')
 if not have['pymongo']:
     sec.exclude('controller.mongodb')
     sec.exclude('tests.test_mongodb')
 
 # kernel:
 sec = test_sections['kernel']
 sec.requires('zmq')
 # The in-process kernel tests are done in a separate section
 sec.exclude('inprocess')
 # importing gtk sets the default encoding, which we want to avoid
 sec.exclude('zmq.gui.gtkembed')
 if not have['matplotlib']:
     sec.exclude('zmq.pylab')
 
 # kernel.inprocess:
 test_sections['kernel.inprocess'].requires('zmq')
 
 # extensions:
 sec = test_sections['extensions']
 if not have['cython']:
     sec.exclude('cythonmagic')
     sec.exclude('tests.test_cythonmagic')
 if not have['oct2py']:
     sec.exclude('octavemagic')
     sec.exclude('tests.test_octavemagic')
 if not have['rpy2'] or not have['numpy']:
     sec.exclude('rmagic')
     sec.exclude('tests.test_rmagic')
 # autoreload does some strange stuff, so move it to its own test section
 sec.exclude('autoreload')
 sec.exclude('tests.test_autoreload')
 test_sections['autoreload'] = TestSection('autoreload',
         ['IPython.extensions.autoreload', 'IPython.extensions.tests.test_autoreload'])
 test_group_names.append('autoreload')
 
 # qt:
 test_sections['qt'].requires('zmq', 'qt', 'pygments')
 
 # html:
 sec = test_sections['html']
 sec.requires('zmq', 'tornado')
 # The notebook 'static' directory contains JS, css and other
 # files for web serving.  Occasionally projects may put a .py
 # file in there (MathJax ships a conf.py), so we might as
 # well play it safe and skip the whole thing.
 sec.exclude('static')
 sec.exclude('fabfile')
 if not have['jinja2']:
     sec.exclude('notebookapp')
 if not have['azure']:
     sec.exclude('services.notebooks.azurenbmanager')
 
 # config:
 # Config files aren't really importable stand-alone
 test_sections['config'].exclude('profile')
 
 # nbconvert:
 sec = test_sections['nbconvert']
 sec.requires('pygments', 'jinja2', 'sphinx')
 # Exclude nbconvert directories containing config files used to test.
 # Executing the config files with iptest would cause an exception.
 sec.exclude('tests.files')
 sec.exclude('exporters.tests.files')
 if not have['tornado']:
     sec.exclude('nbconvert.post_processors.serve')
     sec.exclude('nbconvert.post_processors.tests.test_serve')
 
 #-----------------------------------------------------------------------------
 # Functions and classes
 #-----------------------------------------------------------------------------
 
 def check_exclusions_exist():
     from IPython.utils.path import get_ipython_package_dir
     from IPython.utils.warn import warn
     parent = os.path.dirname(get_ipython_package_dir())
     for sec in test_sections:
         for pattern in sec.exclusions:
             fullpath = pjoin(parent, pattern)
             if not os.path.exists(fullpath) and not glob.glob(fullpath + '.*'):
                 warn("Excluding nonexistent file: %r" % pattern)
 
 
 class ExclusionPlugin(Plugin):
     """A nose plugin to effect our exclusions of files and directories.
     """
     name = 'exclusions'
     score = 3000  # Should come before any other plugins
     
     def __init__(self, exclude_patterns=None):
         """
         Parameters
         ----------
 
         exclude_patterns : sequence of strings, optional
           Filenames containing these patterns (as raw strings, not as regular
           expressions) are excluded from the tests.
         """
         self.exclude_patterns = exclude_patterns or []
         super(ExclusionPlugin, self).__init__()
 
     def options(self, parser, env=os.environ):
         Plugin.options(self, parser, env)
     
     def configure(self, options, config):
         Plugin.configure(self, options, config)
         # Override nose trying to disable plugin.
         self.enabled = True
         
     def wantFile(self, filename):
         """Return whether the given filename should be scanned for tests.
         """
         if any(pat in filename for pat in self.exclude_patterns):
             return False
         return None
 
     def wantDirectory(self, directory):
         """Return whether the given directory should be scanned for tests.
         """
         if any(pat in directory for pat in self.exclude_patterns):
             return False
         return None
 
 
 class StreamCapturer(Thread):
     started = False
     def __init__(self):
         super(StreamCapturer, self).__init__()
         self.streams = []
         self.buffer = BytesIO()
         self.streams_lock = Lock()
         self.buffer_lock = Lock()
         self.stream_added = Event()
         self.stop = Event()
 
     def run(self):
         self.started = True
         while not self.stop.is_set():
             with self.streams_lock:
                 streams = self.streams
 
             if not streams:
                 self.stream_added.wait(timeout=1)
                 self.stream_added.clear()
                 continue
 
             ready = select(streams, [], [], 0.5)[0]
             with self.buffer_lock:
                 for fd in ready:
                     self.buffer.write(os.read(fd, 1024))
     
     def add_stream(self, fd):
         with self.streams_lock:
             self.streams.append(fd)
         self.stream_added.set()
     
     def remove_stream(self, fd):
         with self.streams_lock:
             self.streams.remove(fd)
         
     def reset_buffer(self):
         with self.buffer_lock:
             self.buffer.truncate(0)
             self.buffer.seek(0)
     
     def get_buffer(self):
         with self.buffer_lock:
             return self.buffer.getvalue()
     
     def ensure_started(self):
         if not self.started:
             self.start()
 
 class SubprocessStreamCapturePlugin(Plugin):
     name='subprocstreams'
     def __init__(self):
         Plugin.__init__(self)
         self.stream_capturer = StreamCapturer()
         # This is ugly, but distant parts of the test machinery need to be able
         # to add streams, so we make the object globally accessible.
         nose.ipy_stream_capturer = self.stream_capturer
     
     def configure(self, options, config):
         Plugin.configure(self, options, config)
         # Override nose trying to disable plugin.
         self.enabled = True
     
     def startTest(self, test):
         # Reset log capture
         self.stream_capturer.reset_buffer()
     
     def formatFailure(self, test, err):
         # Show output
         ec, ev, tb = err
+        captured = self.stream_capturer.get_buffer().decode('utf-8', 'replace')
+        if captured.strip():
         ev = safe_str(ev)
         out = [ev, '>> begin captured subprocess output <<',
-                self.stream_capturer.get_buffer().decode('utf-8', 'replace'),
+                    captured,
                 '>> end captured subprocess output <<']
         return ec, '\n'.join(out), tb
     
+        return err
+    
     formatError = formatFailure
     
     def finalize(self, result):
         if self.stream_capturer.started:
             self.stream_capturer.stop.set()
             self.stream_capturer.join()
 
 
 def run_iptest():
     """Run the IPython test suite using nose.
 
     This function is called when this script is **not** called with the form
     `iptest all`.  It simply calls nose with appropriate command line flags
     and accepts all of the standard nose arguments.
     """
     # Apply our monkeypatch to Xunit
     if '--with-xunit' in sys.argv and not hasattr(Xunit, 'orig_addError'):
         monkeypatch_xunit()
 
     warnings.filterwarnings('ignore',
         'This will be removed soon.  Use IPython.testing.util instead')
     
     arg1 = sys.argv[1]
     if arg1 in test_sections:
         section = test_sections[arg1]
         sys.argv[1:2] = section.includes
     elif arg1.startswith('IPython.') and arg1[8:] in test_sections:
         section = test_sections[arg1[8:]]
         sys.argv[1:2] = section.includes
     else:
         section = TestSection(arg1, includes=[arg1])
         
 
     argv = sys.argv + [ '--detailed-errors',  # extra info in tracebacks
 
                         '--with-ipdoctest',
                         '--ipdoctest-tests','--ipdoctest-extension=txt',
 
                         # We add --exe because of setuptools' imbecility (it
                         # blindly does chmod +x on ALL files).  Nose does the
                         # right thing and it tries to avoid executables,
                         # setuptools unfortunately forces our hand here.  This
                         # has been discussed on the distutils list and the
                         # setuptools devs refuse to fix this problem!
                         '--exe',
                         ]
     if '-a' not in argv and '-A' not in argv:
         argv = argv + ['-a', '!crash']
 
     if nose.__version__ >= '0.11':
         # I don't fully understand why we need this one, but depending on what
         # directory the test suite is run from, if we don't give it, 0 tests
         # get run.  Specifically, if the test suite is run from the source dir
         # with an argument (like 'iptest.py IPython.core', 0 tests are run,
         # even if the same call done in this directory works fine).  It appears
         # that if the requested package is in the current dir, nose bails early
         # by default.  Since it's otherwise harmless, leave it in by default
         # for nose >= 0.11, though unfortunately nose 0.10 doesn't support it.
         argv.append('--traverse-namespace')
 
     # use our plugin for doctesting.  It will remove the standard doctest plugin
     # if it finds it enabled
     plugins = [ExclusionPlugin(section.excludes), IPythonDoctest(), KnownFailure(),
                SubprocessStreamCapturePlugin() ]
     
     # Use working directory set by parent process (see iptestcontroller)
     if 'IPTEST_WORKING_DIR' in os.environ:
         os.chdir(os.environ['IPTEST_WORKING_DIR'])
     
     # We need a global ipython running in this process, but the special
     # in-process group spawns its own IPython kernels, so for *that* group we
     # must avoid also opening the global one (otherwise there's a conflict of
     # singletons).  Ultimately the solution to this problem is to refactor our
     # assumptions about what needs to be a singleton and what doesn't (app
     # objects should, individual shells shouldn't).  But for now, this
     # workaround allows the test suite for the inprocess module to complete.
     if 'kernel.inprocess' not in section.name:
         from IPython.testing import globalipapp
         globalipapp.start_ipython()
 
     # Now nose can run
     TestProgram(argv=argv, addplugins=plugins)
 
 if __name__ == '__main__':
     run_iptest()