Prof: enable profiling using the hotshot profiler

This plugin will run tests using the hotshot profiler, which is part of the standard library. To turn it on, use the --with-profile option or set the NOSE_WITH_PROFILE environment variable. Profiler output can be controlled with the --profile-sort and --profile-restrict options, and the profiler output file may be changed with --profile-stats-file.

See the hotshot documentation in the standard library documentation for more details on the various output options.

Options

Plugin

class nose.plugins.prof.Profile

Bases: nose.plugins.base.Plugin

Use this plugin to run tests using the hotshot profiler.

begin()

Create profile stats file and load profiler.

configure(options, conf)

Configure plugin.

finalize(result)

Clean up stats file, if configured to do so.

options(parser, env)

Register commandline options.

prepareTest(test)

Wrap entire test run in prof.runcall().

report(stream)

Output profiler report.

Source

"""This plugin will run tests using the hotshot profiler, which is part
of the standard library. To turn it on, use the ``--with-profile`` option
or set the NOSE_WITH_PROFILE environment variable. Profiler output can be
controlled with the ``--profile-sort`` and ``--profile-restrict`` options,
and the profiler output file may be changed with ``--profile-stats-file``.

See the `hotshot documentation`_ in the standard library documentation for
more details on the various output options.

.. _hotshot documentation: http://docs.python.org/library/hotshot.html
"""

try:
    import hotshot
    from hotshot import stats
except ImportError:
    hotshot, stats = None, None
import logging
import os
import sys
import tempfile
from nose.plugins.base import Plugin
from nose.util import tolist

log = logging.getLogger('nose.plugins')

class Profile(Plugin):
    """
    Use this plugin to run tests using the hotshot profiler. 
    """
    pfile = None
    clean_stats_file = False
    def options(self, parser, env):
        """Register commandline options.
        """
        if not self.available():
            return
        Plugin.options(self, parser, env)
        parser.add_option('--profile-sort', action='store', dest='profile_sort',
                          default=env.get('NOSE_PROFILE_SORT', 'cumulative'),
                          metavar="SORT",
                          help="Set sort order for profiler output")
        parser.add_option('--profile-stats-file', action='store',
                          dest='profile_stats_file',
                          metavar="FILE",
                          default=env.get('NOSE_PROFILE_STATS_FILE'),
                          help='Profiler stats file; default is a new '
                          'temp file on each run')
        parser.add_option('--profile-restrict', action='append',
                          dest='profile_restrict',
                          metavar="RESTRICT",
                          default=env.get('NOSE_PROFILE_RESTRICT'),
                          help="Restrict profiler output. See help for "
                          "pstats.Stats for details")

    def available(cls):
        return hotshot is not None
    available = classmethod(available)

    def begin(self):
        """Create profile stats file and load profiler.
        """
        if not self.available():
            return
        self._create_pfile()
        self.prof = hotshot.Profile(self.pfile)

    def configure(self, options, conf):
        """Configure plugin.
        """
        if not self.available():
            self.enabled = False
            return
        Plugin.configure(self, options, conf)
        self.conf = conf
        if options.profile_stats_file:
            self.pfile = options.profile_stats_file
            self.clean_stats_file = False
        else:
            self.pfile = None
            self.clean_stats_file = True
        self.fileno = None
        self.sort = options.profile_sort
        self.restrict = tolist(options.profile_restrict)

    def prepareTest(self, test):
        """Wrap entire test run in :func:`prof.runcall`.
        """
        if not self.available():
            return
        log.debug('preparing test %s' % test)
        def run_and_profile(result, prof=self.prof, test=test):
            self._create_pfile()
            prof.runcall(test, result)
        return run_and_profile

    def report(self, stream):
        """Output profiler report.
        """
        log.debug('printing profiler report')
        self.prof.close()
        prof_stats = stats.load(self.pfile)
        prof_stats.sort_stats(self.sort)

        # 2.5 has completely different stream handling from 2.4 and earlier.
        # Before 2.5, stats objects have no stream attribute; in 2.5 and later
        # a reference sys.stdout is stored before we can tweak it.
        compat_25 = hasattr(prof_stats, 'stream')
        if compat_25:
            tmp = prof_stats.stream
            prof_stats.stream = stream
        else:
            tmp = sys.stdout
            sys.stdout = stream
        try:
            if self.restrict:
                log.debug('setting profiler restriction to %s', self.restrict)
                prof_stats.print_stats(*self.restrict)
            else:
                prof_stats.print_stats()
        finally:
            if compat_25:
                prof_stats.stream = tmp
            else:
                sys.stdout = tmp

    def finalize(self, result):
        """Clean up stats file, if configured to do so.
        """
        if not self.available():
            return
        try:
            self.prof.close()
        except AttributeError:
            # TODO: is this trying to catch just the case where not
            # hasattr(self.prof, "close")?  If so, the function call should be
            # moved out of the try: suite.
            pass
        if self.clean_stats_file:
            if self.fileno:
                try:
                    os.close(self.fileno)
                except OSError:
                    pass
            try:
                os.unlink(self.pfile)
            except OSError:
                pass
        return None

    def _create_pfile(self):
        if not self.pfile:
            self.fileno, self.pfile = tempfile.mkstemp()
            self.clean_stats_file = True