~bzr-pqm/bzr/bzr.dev

# Copyright (c) 2004 Canonical Limited

#       Author: Robert Collins <robert.collins@canonical.com>

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

#

import sys

import logging

import unittest

class LogCollector(logging.Handler):

    def __init__(self):

        logging.Handler.__init__(self)

        self.records=[]

    def emit(self, record):

        self.records.append(record.getMessage())

def makeCollectingLogger():

    """I make a logger instance that collects its logs for programmatic analysis

    -> (logger, collector)"""

    logger=logging.Logger("collector")

    handler=LogCollector()

    handler.setFormatter(logging.Formatter("%(levelname)s: %(message)s"))

    logger.addHandler(handler)

    return logger, handler

def visitTests(suite, visitor):

    """A foreign method for visiting the tests in a test suite."""

    for test in suite._tests:

        #Abusing types to avoid monkey patching unittest.TestCase. 

        # Maybe that would be better?

        try:

            test.visit(visitor)

        except AttributeError:

            if isinstance(test, unittest.TestCase):

                visitor.visitCase(test)

            elif isinstance(test, unittest.TestSuite):

                visitor.visitSuite(test)

                visitTests(test, visitor)

            else:

                print "unvisitable non-unittest.TestCase element %r (%r)" % (test, test.__class__)

class TestSuite(unittest.TestSuite):

    """I am an extended TestSuite with a visitor interface.

    This is primarily to allow filtering of tests - and suites or

    more in the future. An iterator of just tests wouldn't scale..."""

    def visit(self, visitor):

        """visit the composite. Visiting is depth-first.

        current callbacks are visitSuite and visitCase."""

        visitor.visitSuite(self)

        visitTests(self, visitor)

class TestLoader(unittest.TestLoader):

    """Custom  TestLoader to address some quirks in the stock python one."""

    suiteClass = TestSuite

    def loadTestsFromModuleNames(self, names):

        """use a custom means to load tests from modules.

        There is an undesirable glitch in the python TestLoader where a 

        import error is ignore. We think this can be solved by ensuring the 

        requested name is resolvable, if its not raising the original error.

        """

        result = self.suiteClass()

        for name in names:

            _load_module_by_name(name)

            result.addTests(self.loadTestsFromName(name))

        return result

def _load_module_by_name(mod_name):

    parts = mod_name.split('.')

    module = __import__(mod_name)

    del parts[0]

    # for historical reasons python returns the top-level module even though

    # it loads the submodule; we need to walk down to get the one we want.

    while parts:

        module = getattr(module, parts.pop(0))

    return module

class TestVisitor(object):

    """A visitor for Tests"""

    def visitSuite(self, aTestSuite):

        pass

    def visitCase(self, aTestCase):

        pass