Debug: drop into pdb on errors or failures

This plugin provides --pdb and --pdb-failures options. The --pdb option will drop the test runner into pdb when it encounters an error. To drop into pdb on failure, use --pdb-failures.

Options

--pdb

Drop into debugger on failures or errors

--pdb-failures

Drop into debugger on failures

--pdb-errors

Drop into debugger on errors

Plugin

class nose.plugins.debug.Pdb

Bases: nose.plugins.base.Plugin

Provides –pdb and –pdb-failures options that cause the test runner to drop into pdb if it encounters an error or failure, respectively.

addError(test, err)

Enter pdb if configured to debug errors.

addFailure(test, err)

Enter pdb if configured to debug failures.

configure(options, conf)

Configure which kinds of exceptions trigger plugin.

options(parser, env)

Register commandline options.

Source

"""
This plugin provides ``--pdb`` and ``--pdb-failures`` options. The ``--pdb``
option will drop the test runner into pdb when it encounters an error. To
drop into pdb on failure, use ``--pdb-failures``.
"""

import pdb
from nose.plugins.base import Plugin

class Pdb(Plugin):
    """
    Provides --pdb and --pdb-failures options that cause the test runner to
    drop into pdb if it encounters an error or failure, respectively.
    """
    enabled_for_errors = False
    enabled_for_failures = False
    score = 5 # run last, among builtins
    
    def options(self, parser, env):
        """Register commandline options.
        """
        parser.add_option(
            "--pdb", action="store_true", dest="debugBoth",
            default=env.get('NOSE_PDB', False),
            help="Drop into debugger on failures or errors")
        parser.add_option(
            "--pdb-failures", action="store_true",
            dest="debugFailures",
            default=env.get('NOSE_PDB_FAILURES', False),
            help="Drop into debugger on failures")
        parser.add_option(
            "--pdb-errors", action="store_true",
            dest="debugErrors",
            default=env.get('NOSE_PDB_ERRORS', False),
            help="Drop into debugger on errors")

    def configure(self, options, conf):
        """Configure which kinds of exceptions trigger plugin.
        """
        self.conf = conf
        self.enabled_for_errors = options.debugErrors or options.debugBoth
        self.enabled_for_failures = options.debugFailures or options.debugBoth
        self.enabled = self.enabled_for_failures or self.enabled_for_errors

    def addError(self, test, err):
        """Enter pdb if configured to debug errors.
        """
        if not self.enabled_for_errors:
            return
        self.debug(err)

    def addFailure(self, test, err):
        """Enter pdb if configured to debug failures.
        """
        if not self.enabled_for_failures:
            return
        self.debug(err)

    def debug(self, err):
        import sys # FIXME why is this import here?
        ec, ev, tb = err
        stdout = sys.stdout
        sys.stdout = sys.__stdout__
        try:
            pdb.post_mortem(tb)
        finally:
            sys.stdout = stdout