~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2005, 2006 Canonical Ltd
#
# 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

"""Tests for the osutils wrapper."""

import errno
import os
import socket
import stat
import sys

import bzrlib
from bzrlib import (
    errors,
    osutils,
    )
from bzrlib.errors import BzrBadParameterNotUnicode, InvalidURL
from bzrlib.tests import (
        StringIOWrapper,
        TestCase, 
        TestCaseInTempDir, 
        TestSkipped,
        )


class TestOSUtils(TestCaseInTempDir):

    def test_fancy_rename(self):
        # This should work everywhere
        def rename(a, b):
            osutils.fancy_rename(a, b,
                    rename_func=os.rename,
                    unlink_func=os.unlink)

        open('a', 'wb').write('something in a\n')
        rename('a', 'b')
        self.failIfExists('a')
        self.failUnlessExists('b')
        self.check_file_contents('b', 'something in a\n')

        open('a', 'wb').write('new something in a\n')
        rename('b', 'a')

        self.check_file_contents('a', 'something in a\n')

    def test_rename(self):
        # Rename should be semi-atomic on all platforms
        open('a', 'wb').write('something in a\n')
        osutils.rename('a', 'b')
        self.failIfExists('a')
        self.failUnlessExists('b')
        self.check_file_contents('b', 'something in a\n')

        open('a', 'wb').write('new something in a\n')
        osutils.rename('b', 'a')

        self.check_file_contents('a', 'something in a\n')

    # TODO: test fancy_rename using a MemoryTransport

    def test_01_rand_chars_empty(self):
        result = osutils.rand_chars(0)
        self.assertEqual(result, '')

    def test_02_rand_chars_100(self):
        result = osutils.rand_chars(100)
        self.assertEqual(len(result), 100)
        self.assertEqual(type(result), str)
        self.assertContainsRe(result, r'^[a-z0-9]{100}$')

    def test_is_inside(self):
        is_inside = osutils.is_inside
        self.assertTrue(is_inside('src', 'src/foo.c'))
        self.assertFalse(is_inside('src', 'srccontrol'))
        self.assertTrue(is_inside('src', 'src/a/a/a/foo.c'))
        self.assertTrue(is_inside('foo.c', 'foo.c'))
        self.assertFalse(is_inside('foo.c', ''))
        self.assertTrue(is_inside('', 'foo.c'))

    def test_rmtree(self):
        # Check to remove tree with read-only files/dirs
        os.mkdir('dir')
        f = file('dir/file', 'w')
        f.write('spam')
        f.close()
        # would like to also try making the directory readonly, but at the
        # moment python shutil.rmtree doesn't handle that properly - it would
        # need to chmod the directory before removing things inside it - deferred
        # for now -- mbp 20060505
        # osutils.make_readonly('dir')
        osutils.make_readonly('dir/file')

        osutils.rmtree('dir')

        self.failIfExists('dir/file')
        self.failIfExists('dir')

    def test_file_kind(self):
        self.build_tree(['file', 'dir/'])
        self.assertEquals('file', osutils.file_kind('file'))
        self.assertEquals('directory', osutils.file_kind('dir/'))
        if osutils.has_symlinks():
            os.symlink('symlink', 'symlink')
            self.assertEquals('symlink', osutils.file_kind('symlink'))
        
        # TODO: jam 20060529 Test a block device
        try:
            os.lstat('/dev/null')
        except OSError, e:
            if e.errno not in (errno.ENOENT,):
                raise
        else:
            self.assertEquals('chardev', osutils.file_kind('/dev/null'))

        mkfifo = getattr(os, 'mkfifo', None)
        if mkfifo:
            mkfifo('fifo')
            try:
                self.assertEquals('fifo', osutils.file_kind('fifo'))
            finally:
                os.remove('fifo')

        AF_UNIX = getattr(socket, 'AF_UNIX', None)
        if AF_UNIX:
            s = socket.socket(AF_UNIX)
            s.bind('socket')
            try:
                self.assertEquals('socket', osutils.file_kind('socket'))
            finally:
                os.remove('socket')

    def test_get_umask(self):
        if sys.platform == 'win32':
            # umask always returns '0', no way to set it
            self.assertEqual(0, osutils.get_umask())
            return

        orig_umask = osutils.get_umask()
        try:
            os.umask(0222)
            self.assertEqual(0222, osutils.get_umask())
            os.umask(0022)
            self.assertEqual(0022, osutils.get_umask())
            os.umask(0002)
            self.assertEqual(0002, osutils.get_umask())
            os.umask(0027)
            self.assertEqual(0027, osutils.get_umask())
        finally:
            os.umask(orig_umask)

    def assertFormatedDelta(self, expected, seconds):
        """Assert osutils.format_delta formats as expected"""
        actual = osutils.format_delta(seconds)
        self.assertEqual(expected, actual)

    def test_format_delta(self):
        self.assertFormatedDelta('0 seconds ago', 0)
        self.assertFormatedDelta('1 second ago', 1)
        self.assertFormatedDelta('10 seconds ago', 10)
        self.assertFormatedDelta('59 seconds ago', 59)
        self.assertFormatedDelta('89 seconds ago', 89)
        self.assertFormatedDelta('1 minute, 30 seconds ago', 90)
        self.assertFormatedDelta('3 minutes, 0 seconds ago', 180)
        self.assertFormatedDelta('3 minutes, 1 second ago', 181)
        self.assertFormatedDelta('10 minutes, 15 seconds ago', 615)
        self.assertFormatedDelta('30 minutes, 59 seconds ago', 1859)
        self.assertFormatedDelta('31 minutes, 0 seconds ago', 1860)
        self.assertFormatedDelta('60 minutes, 0 seconds ago', 3600)
        self.assertFormatedDelta('89 minutes, 59 seconds ago', 5399)
        self.assertFormatedDelta('1 hour, 30 minutes ago', 5400)
        self.assertFormatedDelta('2 hours, 30 minutes ago', 9017)
        self.assertFormatedDelta('10 hours, 0 minutes ago', 36000)
        self.assertFormatedDelta('24 hours, 0 minutes ago', 86400)
        self.assertFormatedDelta('35 hours, 59 minutes ago', 129599)
        self.assertFormatedDelta('36 hours, 0 minutes ago', 129600)
        self.assertFormatedDelta('36 hours, 0 minutes ago', 129601)
        self.assertFormatedDelta('36 hours, 1 minute ago', 129660)
        self.assertFormatedDelta('36 hours, 1 minute ago', 129661)
        self.assertFormatedDelta('84 hours, 10 minutes ago', 303002)

        # We handle when time steps the wrong direction because computers
        # don't have synchronized clocks.
        self.assertFormatedDelta('84 hours, 10 minutes in the future', -303002)
        self.assertFormatedDelta('1 second in the future', -1)
        self.assertFormatedDelta('2 seconds in the future', -2)

    def test_dereference_path(self):
        if not osutils.has_symlinks():
            raise TestSkipped('Symlinks are not supported on this platform')
        cwd = osutils.realpath('.')
        os.mkdir('bar')
        bar_path = osutils.pathjoin(cwd, 'bar')
        # Using './' to avoid bug #1213894 (first path component not
        # dereferenced) in Python 2.4.1 and earlier
        self.assertEqual(bar_path, osutils.realpath('./bar'))
        os.symlink('bar', 'foo')
        self.assertEqual(bar_path, osutils.realpath('./foo'))
        
        # Does not dereference terminal symlinks
        foo_path = osutils.pathjoin(cwd, 'foo')
        self.assertEqual(foo_path, osutils.dereference_path('./foo'))

        # Dereferences parent symlinks
        os.mkdir('bar/baz')
        baz_path = osutils.pathjoin(bar_path, 'baz')
        self.assertEqual(baz_path, osutils.dereference_path('./foo/baz'))

        # Dereferences parent symlinks that are the first path element
        self.assertEqual(baz_path, osutils.dereference_path('foo/baz'))

        # Dereferences parent symlinks in absolute paths
        foo_baz_path = osutils.pathjoin(foo_path, 'baz')
        self.assertEqual(baz_path, osutils.dereference_path(foo_baz_path))


class TestSafeUnicode(TestCase):

    def test_from_ascii_string(self):
        self.assertEqual(u'foobar', osutils.safe_unicode('foobar'))

    def test_from_unicode_string_ascii_contents(self):
        self.assertEqual(u'bargam', osutils.safe_unicode(u'bargam'))

    def test_from_unicode_string_unicode_contents(self):
        self.assertEqual(u'bargam\xae', osutils.safe_unicode(u'bargam\xae'))

    def test_from_utf8_string(self):
        self.assertEqual(u'foo\xae', osutils.safe_unicode('foo\xc2\xae'))

    def test_bad_utf8_string(self):
        self.assertRaises(BzrBadParameterNotUnicode,
                          osutils.safe_unicode,
                          '\xbb\xbb')


class TestWin32Funcs(TestCase):
    """Test that the _win32 versions of os utilities return appropriate paths."""

    def test_abspath(self):
        self.assertEqual('C:/foo', osutils._win32_abspath('C:\\foo'))
        self.assertEqual('C:/foo', osutils._win32_abspath('C:/foo'))

    def test_realpath(self):
        self.assertEqual('C:/foo', osutils._win32_realpath('C:\\foo'))
        self.assertEqual('C:/foo', osutils._win32_realpath('C:/foo'))

    def test_pathjoin(self):
        self.assertEqual('path/to/foo', osutils._win32_pathjoin('path', 'to', 'foo'))
        self.assertEqual('C:/foo', osutils._win32_pathjoin('path\\to', 'C:\\foo'))
        self.assertEqual('C:/foo', osutils._win32_pathjoin('path/to', 'C:/foo'))
        self.assertEqual('path/to/foo', osutils._win32_pathjoin('path/to/', 'foo'))
        self.assertEqual('/foo', osutils._win32_pathjoin('C:/path/to/', '/foo'))
        self.assertEqual('/foo', osutils._win32_pathjoin('C:\\path\\to\\', '\\foo'))

    def test_normpath(self):
        self.assertEqual('path/to/foo', osutils._win32_normpath(r'path\\from\..\to\.\foo'))
        self.assertEqual('path/to/foo', osutils._win32_normpath('path//from/../to/./foo'))

    def test_getcwd(self):
        cwd = osutils._win32_getcwd()
        os_cwd = os.getcwdu()
        self.assertEqual(os_cwd[1:].replace('\\', '/'), cwd[1:])
        # win32 is inconsistent whether it returns lower or upper case
        # and even if it was consistent the user might type the other
        # so we force it to uppercase
        # running python.exe under cmd.exe return capital C:\\
        # running win32 python inside a cygwin shell returns lowercase
        self.assertEqual(os_cwd[0].upper(), cwd[0])

    def test_fixdrive(self):
        self.assertEqual('H:/foo', osutils._win32_fixdrive('h:/foo'))
        self.assertEqual('H:/foo', osutils._win32_fixdrive('H:/foo'))
        self.assertEqual('C:\\foo', osutils._win32_fixdrive('c:\\foo'))


class TestWin32FuncsDirs(TestCaseInTempDir):
    """Test win32 functions that create files."""
    
    def test_getcwd(self):
        # Make sure getcwd can handle unicode filenames
        try:
            os.mkdir(u'mu-\xb5')
        except UnicodeError:
            raise TestSkipped("Unable to create Unicode filename")

        os.chdir(u'mu-\xb5')
        # TODO: jam 20060427 This will probably fail on Mac OSX because
        #       it will change the normalization of B\xe5gfors
        #       Consider using a different unicode character, or make
        #       osutils.getcwd() renormalize the path.
        self.assertEndsWith(osutils._win32_getcwd(), u'mu-\xb5')

    def test_mkdtemp(self):
        tmpdir = osutils._win32_mkdtemp(dir='.')
        self.assertFalse('\\' in tmpdir)

    def test_rename(self):
        a = open('a', 'wb')
        a.write('foo\n')
        a.close()
        b = open('b', 'wb')
        b.write('baz\n')
        b.close()

        osutils._win32_rename('b', 'a')
        self.failUnlessExists('a')
        self.failIfExists('b')
        self.assertFileEqual('baz\n', 'a')

    def test_rename_missing_file(self):
        a = open('a', 'wb')
        a.write('foo\n')
        a.close()

        try:
            osutils._win32_rename('b', 'a')
        except (IOError, OSError), e:
            self.assertEqual(errno.ENOENT, e.errno)
        self.assertFileEqual('foo\n', 'a')

    def test_rename_missing_dir(self):
        os.mkdir('a')
        try:
            osutils._win32_rename('b', 'a')
        except (IOError, OSError), e:
            self.assertEqual(errno.ENOENT, e.errno)

    def test_rename_current_dir(self):
        os.mkdir('a')
        os.chdir('a')
        # You can't rename the working directory
        # doing rename non-existant . usually
        # just raises ENOENT, since non-existant
        # doesn't exist.
        try:
            osutils._win32_rename('b', '.')
        except (IOError, OSError), e:
            self.assertEqual(errno.ENOENT, e.errno)

    def test_splitpath(self):
        def check(expected, path):
            self.assertEqual(expected, osutils.splitpath(path))

        check(['a'], 'a')
        check(['a', 'b'], 'a/b')
        check(['a', 'b'], 'a/./b')
        check(['a', '.b'], 'a/.b')
        check(['a', '.b'], 'a\\.b')

        self.assertRaises(errors.BzrError, osutils.splitpath, 'a/../b')


class TestMacFuncsDirs(TestCaseInTempDir):
    """Test mac special functions that require directories."""

    def test_getcwd(self):
        # On Mac, this will actually create Ba\u030agfors
        # but chdir will still work, because it accepts both paths
        try:
            os.mkdir(u'B\xe5gfors')
        except UnicodeError:
            raise TestSkipped("Unable to create Unicode filename")

        os.chdir(u'B\xe5gfors')
        self.assertEndsWith(osutils._mac_getcwd(), u'B\xe5gfors')

    def test_getcwd_nonnorm(self):
        # Test that _mac_getcwd() will normalize this path
        try:
            os.mkdir(u'Ba\u030agfors')
        except UnicodeError:
            raise TestSkipped("Unable to create Unicode filename")

        os.chdir(u'Ba\u030agfors')
        self.assertEndsWith(osutils._mac_getcwd(), u'B\xe5gfors')


class TestSplitLines(TestCase):

    def test_split_unicode(self):
        self.assertEqual([u'foo\n', u'bar\xae'],
                         osutils.split_lines(u'foo\nbar\xae'))
        self.assertEqual([u'foo\n', u'bar\xae\n'],
                         osutils.split_lines(u'foo\nbar\xae\n'))

    def test_split_with_carriage_returns(self):
        self.assertEqual(['foo\rbar\n'],
                         osutils.split_lines('foo\rbar\n'))


class TestWalkDirs(TestCaseInTempDir):

    def test_walkdirs(self):
        tree = [
            '.bzr',
            '0file',
            '1dir/',
            '1dir/0file',
            '1dir/1dir/',
            '2file'
            ]
        self.build_tree(tree)
        expected_dirblocks = [
                (('', '.'),
                 [('0file', '0file', 'file'),
                  ('1dir', '1dir', 'directory'),
                  ('2file', '2file', 'file'),
                 ]
                ),
                (('1dir', './1dir'),
                 [('1dir/0file', '0file', 'file'),
                  ('1dir/1dir', '1dir', 'directory'),
                 ]
                ),
                (('1dir/1dir', './1dir/1dir'),
                 [
                 ]
                ),
            ]
        result = []
        found_bzrdir = False
        for dirdetail, dirblock in osutils.walkdirs('.'):
            if len(dirblock) and dirblock[0][1] == '.bzr':
                # this tests the filtering of selected paths
                found_bzrdir = True
                del dirblock[0]
            result.append((dirdetail, dirblock))

        self.assertTrue(found_bzrdir)
        self.assertEqual(expected_dirblocks,
            [(dirinfo, [line[0:3] for line in block]) for dirinfo, block in result])
        # you can search a subdir only, with a supplied prefix.
        result = []
        for dirblock in osutils.walkdirs('./1dir', '1dir'):
            result.append(dirblock)
        self.assertEqual(expected_dirblocks[1:],
            [(dirinfo, [line[0:3] for line in block]) for dirinfo, block in result])

    def assertPathCompare(self, path_less, path_greater):
        """check that path_less and path_greater compare correctly."""
        self.assertEqual(0, osutils.compare_paths_prefix_order(
            path_less, path_less))
        self.assertEqual(0, osutils.compare_paths_prefix_order(
            path_greater, path_greater))
        self.assertEqual(-1, osutils.compare_paths_prefix_order(
            path_less, path_greater))
        self.assertEqual(1, osutils.compare_paths_prefix_order(
            path_greater, path_less))

    def test_compare_paths_prefix_order(self):
        # root before all else
        self.assertPathCompare("/", "/a")
        # alpha within a dir
        self.assertPathCompare("/a", "/b")
        self.assertPathCompare("/b", "/z")
        # high dirs before lower.
        self.assertPathCompare("/z", "/a/a")
        # except if the deeper dir should be output first
        self.assertPathCompare("/a/b/c", "/d/g")
        # lexical betwen dirs of the same height
        self.assertPathCompare("/a/z", "/z/z")
        self.assertPathCompare("/a/c/z", "/a/d/e")

        # this should also be consistent for no leading / paths
        # root before all else
        self.assertPathCompare("", "a")
        # alpha within a dir
        self.assertPathCompare("a", "b")
        self.assertPathCompare("b", "z")
        # high dirs before lower.
        self.assertPathCompare("z", "a/a")
        # except if the deeper dir should be output first
        self.assertPathCompare("a/b/c", "d/g")
        # lexical betwen dirs of the same height
        self.assertPathCompare("a/z", "z/z")
        self.assertPathCompare("a/c/z", "a/d/e")

    def test_path_prefix_sorting(self):
        """Doing a sort on path prefix should match our sample data."""
        original_paths = [
            'a',
            'a/b',
            'a/b/c',
            'b',
            'b/c',
            'd',
            'd/e',
            'd/e/f',
            'd/f',
            'd/g',
            'g',
            ]

        dir_sorted_paths = [
            'a',
            'b',
            'd',
            'g',
            'a/b',
            'a/b/c',
            'b/c',
            'd/e',
            'd/f',
            'd/g',
            'd/e/f',
            ]

        self.assertEqual(
            dir_sorted_paths,
            sorted(original_paths, key=osutils.path_prefix_key))
        # using the comparison routine shoudl work too:
        self.assertEqual(
            dir_sorted_paths,
            sorted(original_paths, cmp=osutils.compare_paths_prefix_order))


class TestCopyTree(TestCaseInTempDir):
    
    def test_copy_basic_tree(self):
        self.build_tree(['source/', 'source/a', 'source/b/', 'source/b/c'])
        osutils.copy_tree('source', 'target')
        self.assertEqual(['a', 'b'], sorted(os.listdir('target')))
        self.assertEqual(['c'], os.listdir('target/b'))

    def test_copy_tree_target_exists(self):
        self.build_tree(['source/', 'source/a', 'source/b/', 'source/b/c',
                         'target/'])
        osutils.copy_tree('source', 'target')
        self.assertEqual(['a', 'b'], sorted(os.listdir('target')))
        self.assertEqual(['c'], os.listdir('target/b'))

    def test_copy_tree_symlinks(self):
        if not osutils.has_symlinks():
            return
        self.build_tree(['source/'])
        os.symlink('a/generic/path', 'source/lnk')
        osutils.copy_tree('source', 'target')
        self.assertEqual(['lnk'], os.listdir('target'))
        self.assertEqual('a/generic/path', os.readlink('target/lnk'))

    def test_copy_tree_handlers(self):
        processed_files = []
        processed_links = []
        def file_handler(from_path, to_path):
            processed_files.append(('f', from_path, to_path))
        def dir_handler(from_path, to_path):
            processed_files.append(('d', from_path, to_path))
        def link_handler(from_path, to_path):
            processed_links.append((from_path, to_path))
        handlers = {'file':file_handler,
                    'directory':dir_handler,
                    'symlink':link_handler,
                   }

        self.build_tree(['source/', 'source/a', 'source/b/', 'source/b/c'])
        if osutils.has_symlinks():
            os.symlink('a/generic/path', 'source/lnk')
        osutils.copy_tree('source', 'target', handlers=handlers)

        self.assertEqual([('d', 'source', 'target'),
                          ('f', 'source/a', 'target/a'),
                          ('d', 'source/b', 'target/b'),
                          ('f', 'source/b/c', 'target/b/c'),
                         ], processed_files)
        self.failIfExists('target')
        if osutils.has_symlinks():
            self.assertEqual([('source/lnk', 'target/lnk')], processed_links)


class TestTerminalEncoding(TestCase):
    """Test the auto-detection of proper terminal encoding."""

    def setUp(self):
        self._stdout = sys.stdout
        self._stderr = sys.stderr
        self._stdin = sys.stdin
        self._user_encoding = bzrlib.user_encoding

        self.addCleanup(self._reset)

        sys.stdout = StringIOWrapper()
        sys.stdout.encoding = 'stdout_encoding'
        sys.stderr = StringIOWrapper()
        sys.stderr.encoding = 'stderr_encoding'
        sys.stdin = StringIOWrapper()
        sys.stdin.encoding = 'stdin_encoding'
        bzrlib.user_encoding = 'user_encoding'

    def _reset(self):
        sys.stdout = self._stdout
        sys.stderr = self._stderr
        sys.stdin = self._stdin
        bzrlib.user_encoding = self._user_encoding

    def test_get_terminal_encoding(self):
        # first preference is stdout encoding
        self.assertEqual('stdout_encoding', osutils.get_terminal_encoding())

        sys.stdout.encoding = None
        # if sys.stdout is None, fall back to sys.stdin
        self.assertEqual('stdin_encoding', osutils.get_terminal_encoding())

        sys.stdin.encoding = None
        # and in the worst case, use bzrlib.user_encoding
        self.assertEqual('user_encoding', osutils.get_terminal_encoding())


class TestSetUnsetEnv(TestCase):
    """Test updating the environment"""

    def setUp(self):
        super(TestSetUnsetEnv, self).setUp()

        self.assertEqual(None, os.environ.get('BZR_TEST_ENV_VAR'),
                         'Environment was not cleaned up properly.'
                         ' Variable BZR_TEST_ENV_VAR should not exist.')
        def cleanup():
            if 'BZR_TEST_ENV_VAR' in os.environ:
                del os.environ['BZR_TEST_ENV_VAR']

        self.addCleanup(cleanup)

    def test_set(self):
        """Test that we can set an env variable"""
        old = osutils.set_or_unset_env('BZR_TEST_ENV_VAR', 'foo')
        self.assertEqual(None, old)
        self.assertEqual('foo', os.environ.get('BZR_TEST_ENV_VAR'))

    def test_double_set(self):
        """Test that we get the old value out"""
        osutils.set_or_unset_env('BZR_TEST_ENV_VAR', 'foo')
        old = osutils.set_or_unset_env('BZR_TEST_ENV_VAR', 'bar')
        self.assertEqual('foo', old)
        self.assertEqual('bar', os.environ.get('BZR_TEST_ENV_VAR'))

    def test_unicode(self):
        """Environment can only contain plain strings
        
        So Unicode strings must be encoded.
        """
        # Try a few different characters, to see if we can get
        # one that will be valid in the user_encoding
        possible_vals = [u'm\xb5', u'\xe1', u'\u0410']
        for uni_val in possible_vals:
            try:
                env_val = uni_val.encode(bzrlib.user_encoding)
            except UnicodeEncodeError:
                # Try a different character
                pass
            else:
                break
        else:
            raise TestSkipped('Cannot find a unicode character that works in'
                              ' encoding %s' % (bzrlib.user_encoding,))

        old = osutils.set_or_unset_env('BZR_TEST_ENV_VAR', uni_val)
        self.assertEqual(env_val, os.environ.get('BZR_TEST_ENV_VAR'))

    def test_unset(self):
        """Test that passing None will remove the env var"""
        osutils.set_or_unset_env('BZR_TEST_ENV_VAR', 'foo')
        old = osutils.set_or_unset_env('BZR_TEST_ENV_VAR', None)
        self.assertEqual('foo', old)
        self.assertEqual(None, os.environ.get('BZR_TEST_ENV_VAR'))
        self.failIf('BZR_TEST_ENV_VAR' in os.environ)