Source

pynie / subunit / __init__.py

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#
#  subunit: extensions to Python unittest to get test results from subprocesses.
#  Copyright (C) 2005  Robert Collins <robertc@robertcollins.net>
#
#  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 os
from StringIO import StringIO
import subprocess
import sys
import re
import unittest

def test_suite():
    import subunit.tests
    return subunit.tests.test_suite()


def join_dir(base_path, path):
    """
    Returns an absolute path to C{path}, calculated relative to the parent
    of C{base_path}.

    @param base_path: A path to a file or directory.
    @param path: An absolute path, or a path relative to the containing
    directory of C{base_path}.

    @return: An absolute path to C{path}.
    """
    return os.path.join(os.path.dirname(os.path.abspath(base_path)), path)


def tags_to_new_gone(tags):
    """Split a list of tags into a new_set and a gone_set."""
    new_tags = set()
    gone_tags = set()
    for tag in tags:
        if tag[0] == '-':
            gone_tags.add(tag[1:])
        else:
            new_tags.add(tag)
    return new_tags, gone_tags


class TestProtocolServer(object):
    """A class for receiving results from a TestProtocol client.
    
    :ivar tags: The current tags associated with the protocol stream.
    """

    OUTSIDE_TEST = 0
    TEST_STARTED = 1
    READING_FAILURE = 2
    READING_ERROR = 3
    READING_SKIP = 4
    READING_XFAIL = 5
    READING_SUCCESS = 6

    def __init__(self, client, stream=sys.stdout):
        """Create a TestProtocol server instance.

        client should be an object that provides
         - startTest
         - addSuccess
         - addFailure
         - addError
         - stopTest
        methods, i.e. a TestResult.
        """
        self.state = TestProtocolServer.OUTSIDE_TEST
        self.client = client
        self._stream = stream
        self.tags = set()

    def _addError(self, offset, line):
        if (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description == line[offset:-1]):
            self.state = TestProtocolServer.OUTSIDE_TEST
            self.current_test_description = None
            self.client.addError(self._current_test, RemoteError(""))
            self.client.stopTest(self._current_test)
            self._current_test = None
        elif (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description + " [" == line[offset:-1]):
            self.state = TestProtocolServer.READING_ERROR
            self._message = ""
        else:
            self.stdOutLineReceived(line)

    def _addExpectedFail(self, offset, line):
        if (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description == line[offset:-1]):
            self.state = TestProtocolServer.OUTSIDE_TEST
            self.current_test_description = None
            self.client.addSuccess(self._current_test)
            self.client.stopTest(self._current_test)
        elif (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description + " [" == line[offset:-1]):
            self.state = TestProtocolServer.READING_XFAIL
            self._message = ""
        else:
            self.stdOutLineReceived(line)

    def _addFailure(self, offset, line):
        if (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description == line[offset:-1]):
            self.state = TestProtocolServer.OUTSIDE_TEST
            self.current_test_description = None
            self.client.addFailure(self._current_test, RemoteError())
            self.client.stopTest(self._current_test)
        elif (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description + " [" == line[offset:-1]):
            self.state = TestProtocolServer.READING_FAILURE
            self._message = ""
        else:
            self.stdOutLineReceived(line)

    def _addSkip(self, offset, line):
        if (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description == line[offset:-1]):
            self.state = TestProtocolServer.OUTSIDE_TEST
            self.current_test_description = None
            self._skip_or_error()
            self.client.stopTest(self._current_test)
        elif (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description + " [" == line[offset:-1]):
            self.state = TestProtocolServer.READING_SKIP
            self._message = ""
        else:
            self.stdOutLineReceived(line)

    def _skip_or_error(self, message=None):
        """Report the current test as a skip if possible, or else an error."""
        addSkip = getattr(self.client, 'addSkip', None)
        if not callable(addSkip):
            self.client.addError(self._current_test, RemoteError(message))
        else:
            if not message:
                message = "No reason given"
            addSkip(self._current_test, message)

    def _addSuccess(self, offset, line):
        if (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description == line[offset:-1]):
            self._succeedTest()
        elif (self.state == TestProtocolServer.TEST_STARTED and
            self.current_test_description + " [" == line[offset:-1]):
            self.state = TestProtocolServer.READING_SUCCESS
            self._message = ""
        else:
            self.stdOutLineReceived(line)

    def _appendMessage(self, line):
        if line[0:2] == " ]":
            # quoted ] start
            self._message += line[1:]
        else:
            self._message += line

    def endQuote(self, line):
        if self.state == TestProtocolServer.READING_FAILURE:
            self.state = TestProtocolServer.OUTSIDE_TEST
            self.current_test_description = None
            self.client.addFailure(self._current_test,
                                   RemoteError(self._message))
            self.client.stopTest(self._current_test)
        elif self.state == TestProtocolServer.READING_ERROR:
            self.state = TestProtocolServer.OUTSIDE_TEST
            self.current_test_description = None
            self.client.addError(self._current_test,
                                 RemoteError(self._message))
            self.client.stopTest(self._current_test)
        elif self.state == TestProtocolServer.READING_SKIP:
            self.state = TestProtocolServer.OUTSIDE_TEST
            self.current_test_description = None
            self._skip_or_error(self._message)
            self.client.stopTest(self._current_test)
        elif self.state in (
            TestProtocolServer.READING_SUCCESS,
            TestProtocolServer.READING_XFAIL,
            ):
            self._succeedTest()
        else:
            self.stdOutLineReceived(line)

    def _handleTags(self, offset, line):
        """Process a tags command."""
        tags = line[offset:].split()
        new_tags, gone_tags = tags_to_new_gone(tags)
        if self.state == TestProtocolServer.OUTSIDE_TEST:
            update_tags = self.tags
        else:
            update_tags = self._current_test.tags
        update_tags.update(new_tags)
        update_tags.difference_update(gone_tags)

    def lineReceived(self, line):
        """Call the appropriate local method for the received line."""
        if line == "]\n":
            self.endQuote(line)
        elif self.state in (TestProtocolServer.READING_FAILURE,
            TestProtocolServer.READING_ERROR, TestProtocolServer.READING_SKIP,
            TestProtocolServer.READING_SUCCESS,
            TestProtocolServer.READING_XFAIL
            ):
            self._appendMessage(line)
        else:
            parts = line.split(None, 1)
            if len(parts) == 2:
                cmd, rest = parts
                offset = len(cmd) + 1
                cmd = cmd.strip(':')
                if cmd in ('test', 'testing'):
                    self._startTest(offset, line)
                elif cmd == 'error':
                    self._addError(offset, line)
                elif cmd == 'failure':
                    self._addFailure(offset, line)
                elif cmd == 'skip':
                    self._addSkip(offset, line)
                elif cmd in ('success', 'successful'):
                    self._addSuccess(offset, line)
                elif cmd in ('tags',):
                    self._handleTags(offset, line)
                elif cmd in ('time',):
                    # Accept it, but do not do anything with it yet.
                    pass
                elif cmd == 'xfail':
                    self._addExpectedFail(offset, line)
                else:
                    self.stdOutLineReceived(line)
            else:
                self.stdOutLineReceived(line)

    def _lostConnectionInTest(self, state_string):
        error_string = "lost connection during %stest '%s'" % (
            state_string, self.current_test_description)
        self.client.addError(self._current_test, RemoteError(error_string))
        self.client.stopTest(self._current_test)

    def lostConnection(self):
        """The input connection has finished."""
        if self.state == TestProtocolServer.OUTSIDE_TEST:
            return
        if self.state == TestProtocolServer.TEST_STARTED:
            self._lostConnectionInTest('')
        elif self.state == TestProtocolServer.READING_ERROR:
            self._lostConnectionInTest('error report of ')
        elif self.state == TestProtocolServer.READING_FAILURE:
            self._lostConnectionInTest('failure report of ')
        elif self.state == TestProtocolServer.READING_SUCCESS:
            self._lostConnectionInTest('success report of ')
        elif self.state == TestProtocolServer.READING_SKIP:
            self._lostConnectionInTest('skip report of ')
        elif self.state == TestProtocolServer.READING_XFAIL:
            self._lostConnectionInTest('xfail report of ')
        else:
            self._lostConnectionInTest('unknown state of ')

    def readFrom(self, pipe):
        for line in pipe.readlines():
            self.lineReceived(line)
        self.lostConnection()

    def _startTest(self, offset, line):
        """Internal call to change state machine. Override startTest()."""
        if self.state == TestProtocolServer.OUTSIDE_TEST:
            self.state = TestProtocolServer.TEST_STARTED
            self._current_test = RemotedTestCase(line[offset:-1])
            self.current_test_description = line[offset:-1]
            self.client.startTest(self._current_test)
            self._current_test.tags = set(self.tags)
        else:
            self.stdOutLineReceived(line)

    def stdOutLineReceived(self, line):
        self._stream.write(line)

    def _succeedTest(self):
        self.client.addSuccess(self._current_test)
        self.client.stopTest(self._current_test)
        self.current_test_description = None
        self._current_test = None
        self.state = TestProtocolServer.OUTSIDE_TEST


class RemoteException(Exception):
    """An exception that occured remotely to Python."""

    def __eq__(self, other):
        try:
            return self.args == other.args
        except AttributeError:
            return False


class TestProtocolClient(unittest.TestResult):
    """A class that looks like a TestResult and informs a TestProtocolServer."""

    def __init__(self, stream):
        unittest.TestResult.__init__(self)
        self._stream = stream

    def addError(self, test, error):
        """Report an error in test test."""
        self._stream.write("error: %s [\n" % test.id())
        for line in self._exc_info_to_string(error, test).splitlines():
            self._stream.write("%s\n" % line)
        self._stream.write("]\n")

    def addFailure(self, test, error):
        """Report a failure in test test."""
        self._stream.write("failure: %s [\n" % test.id())
        for line in self._exc_info_to_string(error, test).splitlines():
            self._stream.write("%s\n" % line)
        self._stream.write("]\n")

    def addSkip(self, test, reason):
        """Report a skipped test."""
        self._stream.write("skip: %s [\n" % test.id())
        self._stream.write("%s\n" % reason)
        self._stream.write("]\n")

    def addSuccess(self, test):
        """Report a success in a test."""
        self._stream.write("successful: %s\n" % test.id())

    def startTest(self, test):
        """Mark a test as starting its test run."""
        self._stream.write("test: %s\n" % test.id())


def RemoteError(description=""):
    if description == "":
        description = "\n"
    return (RemoteException, RemoteException(description), None)


class RemotedTestCase(unittest.TestCase):
    """A class to represent test cases run in child processes.
    
    Instances of this class are used to provide the Python test API a TestCase
    that can be printed to the screen, introspected for metadata and so on.
    However, as they are a simply a memoisation of a test that was actually
    run in the past by a separate process, they cannot perform any interactive
    actions.
    """

    def __eq__ (self, other):
        try:
            return self.__description == other.__description
        except AttributeError:
            return False

    def __init__(self, description):
        """Create a psuedo test case with description description."""
        self.__description = description

    def error(self, label):
        raise NotImplementedError("%s on RemotedTestCases is not permitted." %
            label)

    def setUp(self):
        self.error("setUp")

    def tearDown(self):
        self.error("tearDown")

    def shortDescription(self):
        return self.__description

    def id(self):
        return "%s" % (self.__description,)

    def __str__(self):
        return "%s (%s)" % (self.__description, self._strclass())

    def __repr__(self):
        return "<%s description='%s'>" % \
               (self._strclass(), self.__description)

    def run(self, result=None):
        if result is None: result = self.defaultTestResult()
        result.startTest(self)
        result.addError(self, RemoteError("Cannot run RemotedTestCases.\n"))
        result.stopTest(self)

    def _strclass(self):
        cls = self.__class__
        return "%s.%s" % (cls.__module__, cls.__name__)


class ExecTestCase(unittest.TestCase):
    """A test case which runs external scripts for test fixtures."""

    def __init__(self, methodName='runTest'):
        """Create an instance of the class that will use the named test
           method when executed. Raises a ValueError if the instance does
           not have a method with the specified name.
        """
        unittest.TestCase.__init__(self, methodName)
        testMethod = getattr(self, methodName)
        if self.command:
            self.script = "%s %s" % (self.command, testMethod.__doc__)
        elif hasattr(sys.modules[self.__class__.__module__], "__file__"):
            self.script = join_dir(sys.modules[self.__class__.__module__].__file__,
                               testMethod.__doc__)
        else:
            self.script = testMethod.__doc__
        #print "using script %s" % self.script

    def countTestCases(self):
        return 1

    def run(self, result=None):
        if result is None: result = self.defaultTestResult()
        self._run(result)

    def debug(self):
        """Run the test without collecting errors in a TestResult"""
        self._run(unittest.TestResult())

    def _run(self, result):
        protocol = TestProtocolServer(result)
        output = subprocess.Popen(self.script, shell=True,
                                  stdout=subprocess.PIPE).communicate()[0]
        protocol.readFrom(StringIO(output))


class IsolatedTestCase(unittest.TestCase):
    """A TestCase which runs its tests in a forked process."""

    def run(self, result=None):
        if result is None: result = self.defaultTestResult()
        run_isolated(unittest.TestCase, self, result)


class IsolatedTestSuite(unittest.TestSuite):
    """A TestCase which runs its tests in a forked process."""

    def run(self, result=None):
        if result is None: result = unittest.TestResult()
        run_isolated(unittest.TestSuite, self, result)


def run_isolated(klass, self, result):
    """Run a test suite or case in a subprocess, using the run method on klass.
    """
    c2pread, c2pwrite = os.pipe()
    # fixme - error -> result
    # now fork
    pid = os.fork()
    if pid == 0:
        # Child
        # Close parent's pipe ends
        os.close(c2pread)
        # Dup fds for child
        os.dup2(c2pwrite, 1)
        # Close pipe fds.
        os.close(c2pwrite)

        # at this point, sys.stdin is redirected, now we want
        # to filter it to escape ]'s.
        ### XXX: test and write that bit.

        result = TestProtocolClient(sys.stdout)
        klass.run(self, result)
        sys.stdout.flush()
        sys.stderr.flush()
        # exit HARD, exit NOW.
        os._exit(0)
    else:
        # Parent
        # Close child pipe ends
        os.close(c2pwrite)
        # hookup a protocol engine
        protocol = TestProtocolServer(result)
        protocol.readFrom(os.fdopen(c2pread, 'rU'))
        os.waitpid(pid, 0)
        # TODO return code evaluation.
    return result


def TAP2SubUnit(tap, subunit):
    """Filter a TAP pipe into a subunit pipe.
    
    :param tap: A tap pipe/stream/file object.
    :param subunit: A pipe/stream/file object to write subunit results to.
    :return: The exit code to exit with.
    """
    BEFORE_PLAN = 0
    AFTER_PLAN = 1
    SKIP_STREAM = 2
    client = TestProtocolClient(subunit)
    state = BEFORE_PLAN
    plan_start = 1
    plan_stop = 0
    def _skipped_test(subunit, plan_start):
        # Some tests were skipped.
        subunit.write('test test %d\n' % plan_start)
        subunit.write('error test %d [\n' % plan_start)
        subunit.write('test missing from TAP output\n')
        subunit.write(']\n')
        return plan_start + 1
    # Test data for the next test to emit
    test_name = None
    log = []
    result = None
    def _emit_test():
        "write out a test"
        if test_name is None:
            return
        subunit.write("test %s\n" % test_name)
        if not log:
            subunit.write("%s %s\n" % (result, test_name))
        else:
            subunit.write("%s %s [\n" % (result, test_name))
        if log:
            for line in log:
                subunit.write("%s\n" % line)
            subunit.write("]\n")
        del log[:]
    for line in tap:
        if state == BEFORE_PLAN:
            match = re.match("(\d+)\.\.(\d+)\s*(?:\#\s+(.*))?\n", line)
            if match:
                state = AFTER_PLAN
                _, plan_stop, comment = match.groups()
                plan_stop = int(plan_stop)
                if plan_start > plan_stop and plan_stop == 0:
                    # skipped file
                    state = SKIP_STREAM
                    subunit.write("test file skip\n")
                    subunit.write("skip file skip [\n")
                    subunit.write("%s\n" % comment)
                    subunit.write("]\n")
                continue
        # not a plan line, or have seen one before
        match = re.match("(ok|not ok)(?:\s+(\d+)?)?(?:\s+([^#]*[^#\s]+)\s*)?(?:\s+#\s+(TODO|SKIP)(?:\s+(.*))?)?\n", line)
        if match:
            # new test, emit current one.
            _emit_test()
            status, number, description, directive, directive_comment = match.groups()
            if status == 'ok':
                result = 'success'
            else:
                result = "failure"
            if description is None:
                description = ''
            else:
                description = ' ' + description
            if directive is not None:
                if directive == 'TODO':
                    result = 'xfail'
                elif directive == 'SKIP':
                    result = 'skip'
                if directive_comment is not None:
                    log.append(directive_comment)
            if number is not None:
                number = int(number)
                while plan_start < number:
                    plan_start = _skipped_test(subunit, plan_start)
            test_name = "test %d%s" % (plan_start, description)
            plan_start += 1
            continue
        match = re.match("Bail out\!(?:\s*(.*))?\n", line)
        if match:
            reason, = match.groups()
            if reason is None:
                extra = ''
            else:
                extra = ' %s' % reason
            _emit_test()
            test_name = "Bail out!%s" % extra
            result = "error"
            state = SKIP_STREAM
            continue
        match = re.match("\#.*\n", line)
        if match:
            log.append(line[:-1])
            continue
        subunit.write(line)
    _emit_test()
    while plan_start <= plan_stop:
        # record missed tests
        plan_start = _skipped_test(subunit, plan_start)
    return 0


def tag_stream(original, filtered, tags):
    """Alter tags on a stream.

    :param original: The input stream.
    :param filtered: The output stream.
    :param tags: The tags to apply. As in a normal stream - a list of 'TAG' or
        '-TAG' commands.

        A 'TAG' command will add the tag to the output stream,
        and override any existing '-TAG' command in that stream.
        Specifically:
         * A global 'tags: TAG' will be added to the start of the stream.
         * Any tags commands with -TAG will have the -TAG removed.

        A '-TAG' command will remove the TAG command from the stream.
        Specifically:
         * A 'tags: -TAG' command will be added to the start of the stream.
         * Any 'tags: TAG' command will have 'TAG' removed from it.
        Additionally, any redundant tagging commands (adding a tag globally
        present, or removing a tag globally removed) are stripped as a
        by-product of the filtering.
    :return: 0
    """
    new_tags, gone_tags = tags_to_new_gone(tags)
    def write_tags(new_tags, gone_tags):
        if new_tags or gone_tags:
            filtered.write("tags: " + ' '.join(new_tags))
            if gone_tags:
                for tag in gone_tags:
                    filtered.write("-" + tag)
            filtered.write("\n")
    write_tags(new_tags, gone_tags)
    # TODO: use the protocol parser and thus don't mangle test comments.
    for line in original:
        if line.startswith("tags:"):
            line_tags = line[5:].split()
            line_new, line_gone = tags_to_new_gone(line_tags)
            line_new = line_new - gone_tags
            line_gone = line_gone - new_tags
            write_tags(line_new, line_gone)
        else:
            filtered.write(line)
    return 0


class ProtocolTestCase(object):
    """A test case which reports a subunit stream."""

    def __init__(self, stream):
        self._stream = stream

    def __call__(self, result=None):
        return self.run(result)

    def run(self, result=None):
        if result is None:
            result = self.defaultTestResult()
        protocol = TestProtocolServer(result)
        line = self._stream.readline()
        while line:
            protocol.lineReceived(line)
            line = self._stream.readline()
        protocol.lostConnection()


class TestResultStats(unittest.TestResult):
    """A pyunit TestResult interface implementation for making statistics.
    
    :ivar total_tests: The total tests seen.
    :ivar passed_tests: The tests that passed.
    :ivar failed_tests: The tests that failed.
    :ivar tags: The tags seen across all tests.
    """

    def __init__(self, stream):
        """Create a TestResultStats which outputs to stream."""
        unittest.TestResult.__init__(self)
        self._stream = stream
        self.failed_tests = 0
        self.skipped_tests = 0
        self.tags = set()

    @property
    def total_tests(self):
        return self.testsRun

    def addError(self, test, err):
        self.failed_tests += 1

    def addFailure(self, test, err):
        self.failed_tests += 1

    def addSkip(self, test, reason):
        self.skipped_tests += 1

    def formatStats(self):
        self._stream.write("Total tests:   %5d\n" % self.total_tests)
        self._stream.write("Passed tests:  %5d\n" % self.passed_tests)
        self._stream.write("Failed tests:  %5d\n" % self.failed_tests)
        self._stream.write("Skipped tests: %5d\n" % self.skipped_tests)
        tags = sorted(self.tags)
        self._stream.write("Tags: %s\n" % (", ".join(tags)))

    @property
    def passed_tests(self):
        return self.total_tests - self.failed_tests - self.skipped_tests

    def stopTest(self, test):
        unittest.TestResult.stopTest(self, test)
        self.tags.update(test.tags)

    def wasSuccessful(self):
        """Tells whether or not this result was a success"""
        return self.failed_tests == 0


class TestResultFilter(unittest.TestResult):
    """A pyunit TestResult interface implementation which filters tests.

    Tests that pass the filter are handed on to another TestResult instance
    for further processing/reporting. To obtain the filtered results, 
    the other instance must be interrogated.

    :ivar result: The result that tests are passed to after filtering.
    """

    def __init__(self, result, filter_error=False, filter_failure=False,
        filter_success=True, filter_skip=False):
        """Create a FilterResult object filtering to result.
        
        :param filter_error: Filter out errors.
        :param filter_failure: Filter out failures.
        :param filter_success: Filter out successful tests.
        :param filter_skip: Filter out skipped tests.
        """
        unittest.TestResult.__init__(self)
        self.result = result
        self._filter_error = filter_error
        self._filter_failure = filter_failure
        self._filter_success = filter_success
        self._filter_skip = filter_skip
        
    def addError(self, test, err):
        if not self._filter_error:
            self.result.startTest(test)
            self.result.addError(test, err)
            self.result.stopTest(test)

    def addFailure(self, test, err):
        if not self._filter_failure:
            self.result.startTest(test)
            self.result.addFailure(test, err)
            self.result.stopTest(test)

    def addSkip(self, test, reason):
        if not self._filter_skip:
            self.result.startTest(test)
            # This is duplicated, it would be nice to have on a 'calls
            # TestResults' mixin perhaps.
            addSkip = getattr(self.result, 'addSkip', None)
            if not callable(addSkip):
                self.result.addError(test, RemoteError(reason))
            else:
                self.result.addSkip(test, reason)
            self.result.stopTest(test)

    def addSuccess(self, test):
        if not self._filter_success:
            self.result.startTest(test)
            self.result.addSuccess(test)
            self.result.stopTest(test)

    def id_to_orig_id(self, id):
        if id.startswith("subunit.RemotedTestCase."):
            return id[len("subunit.RemotedTestCase."):]
        return id