run-tests: display diff before prompting with --interactive

tests/run-tests.py

@@ -1,1143 +1,1143 b''
 #!/usr/bin/env python
 #
 # run-tests.py - Run a set of tests on Mercurial
 #
 # Copyright 2006 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 # Modifying this script is tricky because it has many modes:
 #   - serial (default) vs parallel (-jN, N > 1)
 #   - no coverage (default) vs coverage (-c, -C, -s)
 #   - temp install (default) vs specific hg script (--with-hg, --local)
 #   - tests are a mix of shell scripts and Python scripts
 #
 # If you change this script, it is recommended that you ensure you
 # haven't broken it by running it in various modes with a representative
 # sample of test scripts.  For example:
 #
 #  1) serial, no coverage, temp install:
 #      ./run-tests.py test-s*
 #  2) serial, no coverage, local hg:
 #      ./run-tests.py --local test-s*
 #  3) serial, coverage, temp install:
 #      ./run-tests.py -c test-s*
 #  4) serial, coverage, local hg:
 #      ./run-tests.py -c --local test-s*      # unsupported
 #  5) parallel, no coverage, temp install:
 #      ./run-tests.py -j2 test-s*
 #  6) parallel, no coverage, local hg:
 #      ./run-tests.py -j2 --local test-s*
 #  7) parallel, coverage, temp install:
 #      ./run-tests.py -j2 -c test-s*          # currently broken
 #  8) parallel, coverage, local install:
 #      ./run-tests.py -j2 -c --local test-s*  # unsupported (and broken)
 #  9) parallel, custom tmp dir:
 #      ./run-tests.py -j2 --tmpdir /tmp/myhgtests
 #
 # (You could use any subset of the tests: test-s* happens to match
 # enough that it's worth doing parallel runs, few enough that it
 # completes fairly quickly, includes both shell and Python scripts, and
 # includes some scripts that run daemon processes.)
 
 from distutils import version
 import difflib
 import errno
 import optparse
 import os
 import shutil
 import subprocess
 import signal
 import sys
 import tempfile
 import time
 import re
 import threading
 
 closefds = os.name == 'posix'
 def Popen4(cmd, timeout):
     p = subprocess.Popen(cmd, shell=True, bufsize=-1,
                          close_fds=closefds,
                          stdin=subprocess.PIPE, stdout=subprocess.PIPE,
                          stderr=subprocess.STDOUT)
     p.fromchild = p.stdout
     p.tochild = p.stdin
     p.childerr = p.stderr
 
     if timeout:
         p.timeout = False
         def t():
             start = time.time()
             while time.time() - start < timeout and p.returncode is None:
                 time.sleep(1)
             p.timeout = True
             if p.returncode is None:
                 try:
                     p.terminate()
                 except OSError:
                     pass
         threading.Thread(target=t).start()
 
     return p
 
 # reserved exit code to skip test (used by hghave)
 SKIPPED_STATUS = 80
 SKIPPED_PREFIX = 'skipped: '
 FAILED_PREFIX  = 'hghave check failed: '
 PYTHON = sys.executable
 IMPL_PATH = 'PYTHONPATH'
 if 'java' in sys.platform:
     IMPL_PATH = 'JYTHONPATH'
 
 requiredtools = ["python", "diff", "grep", "unzip", "gunzip", "bunzip2", "sed"]
 
 defaults = {
     'jobs': ('HGTEST_JOBS', 1),
     'timeout': ('HGTEST_TIMEOUT', 180),
     'port': ('HGTEST_PORT', 20059),
 }
 
 def parseargs():
     parser = optparse.OptionParser("%prog [options] [tests]")
 
     # keep these sorted
     parser.add_option("--blacklist", action="append",
         help="skip tests listed in the specified blacklist file")
     parser.add_option("-C", "--annotate", action="store_true",
         help="output files annotated with coverage")
     parser.add_option("--child", type="int",
         help="run as child process, summary to given fd")
     parser.add_option("-c", "--cover", action="store_true",
         help="print a test coverage report")
     parser.add_option("-d", "--debug", action="store_true",
         help="debug mode: write output of test scripts to console"
              " rather than capturing and diff'ing it (disables timeout)")
     parser.add_option("-f", "--first", action="store_true",
         help="exit on the first test failure")
     parser.add_option("--inotify", action="store_true",
         help="enable inotify extension when running tests")
     parser.add_option("-i", "--interactive", action="store_true",
         help="prompt to accept changed output")
     parser.add_option("-j", "--jobs", type="int",
         help="number of jobs to run in parallel"
              " (default: $%s or %d)" % defaults['jobs'])
     parser.add_option("--keep-tmpdir", action="store_true",
         help="keep temporary directory after running tests")
     parser.add_option("-k", "--keywords",
         help="run tests matching keywords")
     parser.add_option("-l", "--local", action="store_true",
         help="shortcut for --with-hg=<testdir>/../hg")
     parser.add_option("-n", "--nodiff", action="store_true",
         help="skip showing test changes")
     parser.add_option("-p", "--port", type="int",
         help="port on which servers should listen"
              " (default: $%s or %d)" % defaults['port'])
     parser.add_option("--pure", action="store_true",
         help="use pure Python code instead of C extensions")
     parser.add_option("-R", "--restart", action="store_true",
         help="restart at last error")
     parser.add_option("-r", "--retest", action="store_true",
         help="retest failed tests")
     parser.add_option("-S", "--noskips", action="store_true",
         help="don't report skip tests verbosely")
     parser.add_option("-t", "--timeout", type="int",
         help="kill errant tests after TIMEOUT seconds"
              " (default: $%s or %d)" % defaults['timeout'])
     parser.add_option("--tmpdir", type="string",
         help="run tests in the given temporary directory"
              " (implies --keep-tmpdir)")
     parser.add_option("-v", "--verbose", action="store_true",
         help="output verbose messages")
     parser.add_option("--view", type="string",
         help="external diff viewer")
     parser.add_option("--with-hg", type="string",
         metavar="HG",
         help="test using specified hg script rather than a "
              "temporary installation")
     parser.add_option("-3", "--py3k-warnings", action="store_true",
         help="enable Py3k warnings on Python 2.6+")
 
     for option, default in defaults.items():
         defaults[option] = int(os.environ.get(*default))
     parser.set_defaults(**defaults)
     (options, args) = parser.parse_args()
 
     # jython is always pure
     if 'java' in sys.platform or '__pypy__' in sys.modules:
         options.pure = True
 
     if options.with_hg:
         if not (os.path.isfile(options.with_hg) and
                 os.access(options.with_hg, os.X_OK)):
             parser.error('--with-hg must specify an executable hg script')
         if not os.path.basename(options.with_hg) == 'hg':
             sys.stderr.write('warning: --with-hg should specify an hg script')
     if options.local:
         testdir = os.path.dirname(os.path.realpath(sys.argv[0]))
         hgbin = os.path.join(os.path.dirname(testdir), 'hg')
         if not os.access(hgbin, os.X_OK):
             parser.error('--local specified, but %r not found or not executable'
                          % hgbin)
         options.with_hg = hgbin
 
     options.anycoverage = options.cover or options.annotate
     if options.anycoverage:
         try:
             import coverage
             covver = version.StrictVersion(coverage.__version__).version
             if covver < (3, 3):
                 parser.error('coverage options require coverage 3.3 or later')
         except ImportError:
             parser.error('coverage options now require the coverage package')
 
     if options.anycoverage and options.local:
         # this needs some path mangling somewhere, I guess
         parser.error("sorry, coverage options do not work when --local "
                      "is specified")
 
     global vlog
     if options.verbose:
         if options.jobs > 1 or options.child is not None:
             pid = "[%d]" % os.getpid()
         else:
             pid = None
         def vlog(*msg):
             if pid:
                 print pid,
             for m in msg:
                 print m,
             print
             sys.stdout.flush()
     else:
         vlog = lambda *msg: None
 
     if options.tmpdir:
         options.tmpdir = os.path.expanduser(options.tmpdir)
 
     if options.jobs < 1:
         parser.error('--jobs must be positive')
     if options.interactive and options.jobs > 1:
         print '(--interactive overrides --jobs)'
         options.jobs = 1
     if options.interactive and options.debug:
         parser.error("-i/--interactive and -d/--debug are incompatible")
     if options.debug:
         if options.timeout != defaults['timeout']:
             sys.stderr.write(
                 'warning: --timeout option ignored with --debug\n')
         options.timeout = 0
     if options.py3k_warnings:
         if sys.version_info[:2] < (2, 6) or sys.version_info[:2] >= (3, 0):
             parser.error('--py3k-warnings can only be used on Python 2.6+')
     if options.blacklist:
         blacklist = dict()
         for filename in options.blacklist:
             try:
                 path = os.path.expanduser(os.path.expandvars(filename))
                 f = open(path, "r")
             except IOError, err:
                 if err.errno != errno.ENOENT:
                     raise
                 print "warning: no such blacklist file: %s" % filename
                 continue
 
             for line in f.readlines():
                 line = line.split('#', 1)[0].strip()
                 if line:
                     blacklist[line] = filename
 
             f.close()
 
         options.blacklist = blacklist
 
     return (options, args)
 
 def rename(src, dst):
     """Like os.rename(), trade atomicity and opened files friendliness
     for existing destination support.
     """
     shutil.copy(src, dst)
     os.remove(src)
 
 def splitnewlines(text):
     '''like str.splitlines, but only split on newlines.
     keep line endings.'''
     i = 0
     lines = []
     while True:
         n = text.find('\n', i)
         if n == -1:
             last = text[i:]
             if last:
                 lines.append(last)
             return lines
         lines.append(text[i:n + 1])
         i = n + 1
 
 def parsehghaveoutput(lines):
     '''Parse hghave log lines.
     Return tuple of lists (missing, failed):
       * the missing/unknown features
       * the features for which existence check failed'''
     missing = []
     failed = []
     for line in lines:
         if line.startswith(SKIPPED_PREFIX):
             line = line.splitlines()[0]
             missing.append(line[len(SKIPPED_PREFIX):])
         elif line.startswith(FAILED_PREFIX):
             line = line.splitlines()[0]
             failed.append(line[len(FAILED_PREFIX):])
 
     return missing, failed
 
 def showdiff(expected, output, ref, err):
     for line in difflib.unified_diff(expected, output, ref, err):
         sys.stdout.write(line)
 
 def findprogram(program):
     """Search PATH for a executable program"""
     for p in os.environ.get('PATH', os.defpath).split(os.pathsep):
         name = os.path.join(p, program)
         if os.access(name, os.X_OK):
             return name
     return None
 
 def checktools():
     # Before we go any further, check for pre-requisite tools
     # stuff from coreutils (cat, rm, etc) are not tested
     for p in requiredtools:
         if os.name == 'nt':
             p += '.exe'
         found = findprogram(p)
         if found:
             vlog("# Found prerequisite", p, "at", found)
         else:
             print "WARNING: Did not find prerequisite tool: "+p
 
 def killdaemons():
     # Kill off any leftover daemon processes
     try:
         fp = open(DAEMON_PIDS)
         for line in fp:
             try:
                 pid = int(line)
             except ValueError:
                 continue
             try:
                 os.kill(pid, 0)
                 vlog('# Killing daemon process %d' % pid)
                 os.kill(pid, signal.SIGTERM)
                 time.sleep(0.25)
                 os.kill(pid, 0)
                 vlog('# Daemon process %d is stuck - really killing it' % pid)
                 os.kill(pid, signal.SIGKILL)
             except OSError, err:
                 if err.errno != errno.ESRCH:
                     raise
         fp.close()
         os.unlink(DAEMON_PIDS)
     except IOError:
         pass
 
 def cleanup(options):
     if not options.keep_tmpdir:
         vlog("# Cleaning up HGTMP", HGTMP)
         shutil.rmtree(HGTMP, True)
 
 def usecorrectpython():
     # some tests run python interpreter. they must use same
     # interpreter we use or bad things will happen.
     exedir, exename = os.path.split(sys.executable)
     if exename == 'python':
         path = findprogram('python')
         if os.path.dirname(path) == exedir:
             return
     vlog('# Making python executable in test path use correct Python')
     mypython = os.path.join(BINDIR, 'python')
     try:
         os.symlink(sys.executable, mypython)
     except AttributeError:
         # windows fallback
         shutil.copyfile(sys.executable, mypython)
         shutil.copymode(sys.executable, mypython)
 
 def installhg(options):
     vlog("# Performing temporary installation of HG")
     installerrs = os.path.join("tests", "install.err")
     pure = options.pure and "--pure" or ""
 
     # Run installer in hg root
     script = os.path.realpath(sys.argv[0])
     hgroot = os.path.dirname(os.path.dirname(script))
     os.chdir(hgroot)
     nohome = '--home=""'
     if os.name == 'nt':
         # The --home="" trick works only on OS where os.sep == '/'
         # because of a distutils convert_path() fast-path. Avoid it at
         # least on Windows for now, deal with .pydistutils.cfg bugs
         # when they happen.
         nohome = ''
     cmd = ('%s setup.py %s clean --all'
            ' build --build-base="%s"'
            ' install --force --prefix="%s" --install-lib="%s"'
            ' --install-scripts="%s" %s >%s 2>&1'
            % (sys.executable, pure, os.path.join(HGTMP, "build"),
               INST, PYTHONDIR, BINDIR, nohome, installerrs))
     vlog("# Running", cmd)
     if os.system(cmd) == 0:
         if not options.verbose:
             os.remove(installerrs)
     else:
         f = open(installerrs)
         for line in f:
             print line,
         f.close()
         sys.exit(1)
     os.chdir(TESTDIR)
 
     usecorrectpython()
 
     vlog("# Installing dummy diffstat")
     f = open(os.path.join(BINDIR, 'diffstat'), 'w')
     f.write('#!' + sys.executable + '\n'
             'import sys\n'
             'files = 0\n'
             'for line in sys.stdin:\n'
             '    if line.startswith("diff "):\n'
             '        files += 1\n'
             'sys.stdout.write("files patched: %d\\n" % files)\n')
     f.close()
     os.chmod(os.path.join(BINDIR, 'diffstat'), 0700)
 
     if options.py3k_warnings and not options.anycoverage:
         vlog("# Updating hg command to enable Py3k Warnings switch")
         f = open(os.path.join(BINDIR, 'hg'), 'r')
         lines = [line.rstrip() for line in f]
         lines[0] += ' -3'
         f.close()
         f = open(os.path.join(BINDIR, 'hg'), 'w')
         for line in lines:
             f.write(line + '\n')
         f.close()
 
     if options.anycoverage:
         custom = os.path.join(TESTDIR, 'sitecustomize.py')
         target = os.path.join(PYTHONDIR, 'sitecustomize.py')
         vlog('# Installing coverage trigger to %s' % target)
         shutil.copyfile(custom, target)
         rc = os.path.join(TESTDIR, '.coveragerc')
         vlog('# Installing coverage rc to %s' % rc)
         os.environ['COVERAGE_PROCESS_START'] = rc
         fn = os.path.join(INST, '..', '.coverage')
         os.environ['COVERAGE_FILE'] = fn
 
 def outputcoverage(options):
 
     vlog('# Producing coverage report')
     os.chdir(PYTHONDIR)
 
     def covrun(*args):
         cmd = 'coverage %s' % ' '.join(args)
         vlog('# Running: %s' % cmd)
         os.system(cmd)
 
     if options.child:
         return
 
     covrun('-c')
     omit = ','.join([BINDIR, TESTDIR])
     covrun('-i', '-r', '"--omit=%s"' % omit) # report
     if options.annotate:
         adir = os.path.join(TESTDIR, 'annotated')
         if not os.path.isdir(adir):
             os.mkdir(adir)
         covrun('-i', '-a', '"--directory=%s"' % adir, '"--omit=%s"' % omit)
 
 def pytest(test, options, replacements):
     py3kswitch = options.py3k_warnings and ' -3' or ''
     cmd = '%s%s "%s"' % (PYTHON, py3kswitch, test)
     vlog("# Running", cmd)
     return run(cmd, options, replacements)
 
 def shtest(test, options, replacements):
     cmd = '"%s"' % test
     vlog("# Running", cmd)
     return run(cmd, options, replacements)
 
 needescape = re.compile(r'[\x00-\x08\x0b-\x1f\x7f-\xff]').search
 escapesub = re.compile(r'[\x00-\x08\x0b-\x1f\\\x7f-\xff]').sub
 escapemap = dict((chr(i), r'\x%02x' % i) for i in range(256))
 escapemap.update({'\\': '\\\\', '\r': r'\r'})
 def escapef(m):
     return escapemap[m.group(0)]
 def stringescape(s):
     return escapesub(escapef, s)
 
 def tsttest(test, options, replacements):
     t = open(test)
     out = []
     script = []
     salt = "SALT" + str(time.time())
 
     pos = prepos = -1
     after = {}
     expected = {}
     for n, l in enumerate(t):
         if not l.endswith('\n'):
             l += '\n'
         if l.startswith('  $ '): # commands
             after.setdefault(pos, []).append(l)
             prepos = pos
             pos = n
             script.append('echo %s %s $?\n' % (salt, n))
             script.append(l[4:])
         elif l.startswith('  > '): # continuations
             after.setdefault(prepos, []).append(l)
             script.append(l[4:])
         elif l.startswith('  '): # results
             # queue up a list of expected results
             expected.setdefault(pos, []).append(l[2:])
         else:
             # non-command/result - queue up for merged output
             after.setdefault(pos, []).append(l)
 
     t.close()
 
     script.append('echo %s %s $?\n' % (salt, n + 1))
 
     fd, name = tempfile.mkstemp(suffix='hg-tst')
 
     try:
         for l in script:
             os.write(fd, l)
         os.close(fd)
 
         cmd = '/bin/sh "%s"' % name
         vlog("# Running", cmd)
         exitcode, output = run(cmd, options, replacements)
         # do not merge output if skipped, return hghave message instead
         # similarly, with --debug, output is None
         if exitcode == SKIPPED_STATUS or output is None:
             return exitcode, output
     finally:
         os.remove(name)
 
     def rematch(el, l):
         try:
             # ensure that the regex matches to the end of the string
             return re.match(el + r'\Z', l)
         except re.error:
             # el is an invalid regex
             return False
 
     def globmatch(el, l):
         # The only supported special characters are * and ?. Escaping is
         # supported.
         i, n = 0, len(el)
         res = ''
         while i < n:
             c = el[i]
             i += 1
             if c == '\\' and el[i] in '*?\\':
                 res += el[i - 1:i + 1]
                 i += 1
             elif c == '*':
                 res += '.*'
             elif c == '?':
                 res += '.'
             else:
                 res += re.escape(c)
         return rematch(res, l)
 
     pos = -1
     postout = []
     ret = 0
     for n, l in enumerate(output):
         lout, lcmd = l, None
         if salt in l:
             lout, lcmd = l.split(salt, 1)
 
         if lout:
             if lcmd:
                 lout += ' (no-eol)\n'
 
             el = None
             if pos in expected and expected[pos]:
                 el = expected[pos].pop(0)
 
             if el == lout: # perfect match (fast)
                 postout.append("  " + lout)
             elif (el and
                   (el.endswith(" (re)\n") and rematch(el[:-6] + '\n', lout) or
                    el.endswith(" (glob)\n") and globmatch(el[:-8] + '\n', lout)
                    or el.endswith(" (esc)\n") and
                       el.decode('string-escape') == l)):
                 postout.append("  " + el) # fallback regex/glob/esc match
             else:
                 if needescape(lout):
                     lout = stringescape(lout.rstrip('\n')) + " (esc)\n"
                 postout.append("  " + lout) # let diff deal with it
 
         if lcmd:
             # add on last return code
             ret = int(lcmd.split()[1])
             if ret != 0:
                 postout.append("  [%s]\n" % ret)
             if pos in after:
                 postout += after.pop(pos)
             pos = int(lcmd.split()[0])
 
     if pos in after:
         postout += after.pop(pos)
 
     return exitcode, postout
 
 wifexited = getattr(os, "WIFEXITED", lambda x: False)
 def run(cmd, options, replacements):
     """Run command in a sub-process, capturing the output (stdout and stderr).
     Return a tuple (exitcode, output).  output is None in debug mode."""
     # TODO: Use subprocess.Popen if we're running on Python 2.4
     if options.debug:
         proc = subprocess.Popen(cmd, shell=True)
         ret = proc.wait()
         return (ret, None)
 
     if os.name == 'nt' or sys.platform.startswith('java'):
         tochild, fromchild = os.popen4(cmd)
         tochild.close()
         output = fromchild.read()
         ret = fromchild.close()
         if ret is None:
             ret = 0
     else:
         proc = Popen4(cmd, options.timeout)
         def cleanup():
             try:
                 proc.terminate()
             except OSError:
                 pass
             ret = proc.wait()
             if ret == 0:
                 ret = signal.SIGTERM << 8
             killdaemons()
             return ret
 
         output = ''
         proc.tochild.close()
 
         try:
             output = proc.fromchild.read()
         except KeyboardInterrupt:
             vlog('# Handling keyboard interrupt')
             cleanup()
             raise
 
         ret = proc.wait()
         if wifexited(ret):
             ret = os.WEXITSTATUS(ret)
 
         if proc.timeout:
             ret = 'timeout'
 
         if ret:
             killdaemons()
 
     for s, r in replacements:
         output = re.sub(s, r, output)
     return ret, splitnewlines(output)
 
 def runone(options, test):
     '''tristate output:
     None -> skipped
     True -> passed
     False -> failed'''
 
     global results, resultslock, iolock
 
     testpath = os.path.join(TESTDIR, test)
 
     def result(l, e):
         resultslock.acquire()
         results[l].append(e)
         resultslock.release()
 
     def skip(msg):
         if not options.verbose:
             result('s', (test, msg))
         else:
             iolock.acquire()
             print "\nSkipping %s: %s" % (testpath, msg)
             iolock.release()
         return None
 
     def fail(msg, ret):
         if not options.nodiff:
             iolock.acquire()
             print "\nERROR: %s %s" % (testpath, msg)
             iolock.release()
         if (not ret and options.interactive
             and os.path.exists(testpath + ".err")):
             iolock.acquire()
             print "Accept this change? [n] ",
             answer = sys.stdin.readline().strip()
             iolock.release()
             if answer.lower() in "y yes".split():
                 if test.endswith(".t"):
                     rename(testpath + ".err", testpath)
                 else:
                     rename(testpath + ".err", testpath + ".out")
                 return
         result('f', (test, msg))
 
     def success():
         result('p', test)
 
     def ignore(msg):
         result('i', (test, msg))
 
     if (test.startswith("test-") and '~' not in test and
         ('.' not in test or test.endswith('.py') or
          test.endswith('.bat') or test.endswith('.t'))):
         if not os.path.exists(test):
             skip("doesn't exist")
             return None
     else:
         return None # not a supported test, don't record
 
     if options.blacklist:
         filename = options.blacklist.get(test)
         if filename is not None:
             skip("blacklisted")
             return None
 
     if options.retest and not os.path.exists(test + ".err"):
         ignore("not retesting")
         return None
 
     if options.keywords:
         fp = open(test)
         t = fp.read().lower() + test.lower()
         fp.close()
         for k in options.keywords.lower().split():
             if k in t:
                 break
             else:
                 ignore("doesn't match keyword")
                 return None
 
     vlog("# Test", test)
 
     # create a fresh hgrc
     hgrc = open(HGRCPATH, 'w+')
     hgrc.write('[ui]\n')
     hgrc.write('slash = True\n')
     hgrc.write('[defaults]\n')
     hgrc.write('backout = -d "0 0"\n')
     hgrc.write('commit = -d "0 0"\n')
     hgrc.write('tag = -d "0 0"\n')
     if options.inotify:
         hgrc.write('[extensions]\n')
         hgrc.write('inotify=\n')
         hgrc.write('[inotify]\n')
         hgrc.write('pidfile=%s\n' % DAEMON_PIDS)
         hgrc.write('appendpid=True\n')
     hgrc.close()
 
     ref = os.path.join(TESTDIR, test+".out")
     err = os.path.join(TESTDIR, test+".err")
     if os.path.exists(err):
         os.remove(err)       # Remove any previous output files
     try:
         tf = open(testpath)
         firstline = tf.readline().rstrip()
         tf.close()
     except:
         firstline = ''
     lctest = test.lower()
 
     if lctest.endswith('.py') or firstline == '#!/usr/bin/env python':
         runner = pytest
     elif lctest.endswith('.t'):
         runner = tsttest
         ref = testpath
     else:
         # do not try to run non-executable programs
         if not os.access(testpath, os.X_OK):
             return skip("not executable")
         runner = shtest
 
     # Make a tmp subdirectory to work in
     testtmp = os.environ["TESTTMP"] = os.environ["HOME"] = \
         os.path.join(HGTMP, test)
 
     os.mkdir(testtmp)
     os.chdir(testtmp)
 
     ret, out = runner(testpath, options, [
         (re.escape(testtmp), '$TESTTMP'),
         (r':%s\b' % options.port, ':$HGPORT'),
         (r':%s\b' % (options.port + 1), ':$HGPORT1'),
         (r':%s\b' % (options.port + 2), ':$HGPORT2'),
         ])
     vlog("# Ret was:", ret)
 
     mark = '.'
     if ret == 0:
         success()
 
     skipped = (ret == SKIPPED_STATUS)
 
     # If we're not in --debug mode and reference output file exists,
     # check test output against it.
     if options.debug:
         refout = None                   # to match "out is None"
     elif os.path.exists(ref):
         f = open(ref, "r")
         refout = splitnewlines(f.read())
         f.close()
     else:
         refout = []
 
     if (ret != 0 or out != refout) and not skipped and not options.debug:
         # Save errors to a file for diagnosis
         f = open(err, "wb")
         for line in out:
             f.write(line)
         f.close()
 
     if skipped:
         mark = 's'
         if out is None:                 # debug mode: nothing to parse
             missing = ['unknown']
             failed = None
         else:
             missing, failed = parsehghaveoutput(out)
         if not missing:
             missing = ['irrelevant']
         if failed:
             fail("hghave failed checking for %s" % failed[-1], ret)
             skipped = False
         else:
             skip(missing[-1])
     elif ret == 'timeout':
         mark = 't'
         fail("timed out", ret)
     elif out != refout:
         mark = '!'
-        if ret:
-            fail("output changed and returned error code %d" % ret, ret)
-        else:
-            fail("output changed", ret)
-        if ret != 'timeout' and not options.nodiff:
+        if not options.nodiff:
             iolock.acquire()
             if options.view:
                 os.system("%s %s %s" % (options.view, ref, err))
             else:
                 showdiff(refout, out, ref, err)
             iolock.release()
+        if ret:
+            fail("output changed and returned error code %d" % ret, ret)
+        else:
+            fail("output changed", ret)
         ret = 1
     elif ret:
         mark = '!'
         fail("returned error code %d" % ret, ret)
 
     if not options.verbose:
         iolock.acquire()
         sys.stdout.write(mark)
         sys.stdout.flush()
         iolock.release()
 
     killdaemons()
 
     os.chdir(TESTDIR)
     if not options.keep_tmpdir:
         shutil.rmtree(testtmp, True)
     if skipped:
         return None
     return ret == 0
 
 _hgpath = None
 
 def _gethgpath():
     """Return the path to the mercurial package that is actually found by
     the current Python interpreter."""
     global _hgpath
     if _hgpath is not None:
         return _hgpath
 
     cmd = '%s -c "import mercurial; print mercurial.__path__[0]"'
     pipe = os.popen(cmd % PYTHON)
     try:
         _hgpath = pipe.read().strip()
     finally:
         pipe.close()
     return _hgpath
 
 def _checkhglib(verb):
     """Ensure that the 'mercurial' package imported by python is
     the one we expect it to be.  If not, print a warning to stderr."""
     expecthg = os.path.join(PYTHONDIR, 'mercurial')
     actualhg = _gethgpath()
     if actualhg != expecthg:
         sys.stderr.write('warning: %s with unexpected mercurial lib: %s\n'
                          '         (expected %s)\n'
                          % (verb, actualhg, expecthg))
 
 def runchildren(options, tests):
     if INST:
         installhg(options)
         _checkhglib("Testing")
 
     optcopy = dict(options.__dict__)
     optcopy['jobs'] = 1
     del optcopy['blacklist']
     if optcopy['with_hg'] is None:
         optcopy['with_hg'] = os.path.join(BINDIR, "hg")
     optcopy.pop('anycoverage', None)
 
     opts = []
     for opt, value in optcopy.iteritems():
         name = '--' + opt.replace('_', '-')
         if value is True:
             opts.append(name)
         elif value is not None:
             opts.append(name + '=' + str(value))
 
     tests.reverse()
     jobs = [[] for j in xrange(options.jobs)]
     while tests:
         for job in jobs:
             if not tests:
                 break
             job.append(tests.pop())
     fps = {}
 
     for j, job in enumerate(jobs):
         if not job:
             continue
         rfd, wfd = os.pipe()
         childopts = ['--child=%d' % wfd, '--port=%d' % (options.port + j * 3)]
         childtmp = os.path.join(HGTMP, 'child%d' % j)
         childopts += ['--tmpdir', childtmp]
         cmdline = [PYTHON, sys.argv[0]] + opts + childopts + job
         vlog(' '.join(cmdline))
         fps[os.spawnvp(os.P_NOWAIT, cmdline[0], cmdline)] = os.fdopen(rfd, 'r')
         os.close(wfd)
     signal.signal(signal.SIGINT, signal.SIG_IGN)
     failures = 0
     tested, skipped, failed = 0, 0, 0
     skips = []
     fails = []
     while fps:
         pid, status = os.wait()
         fp = fps.pop(pid)
         l = fp.read().splitlines()
         try:
             test, skip, fail = map(int, l[:3])
         except ValueError:
             test, skip, fail = 0, 0, 0
         split = -fail or len(l)
         for s in l[3:split]:
             skips.append(s.split(" ", 1))
         for s in l[split:]:
             fails.append(s.split(" ", 1))
         tested += test
         skipped += skip
         failed += fail
         vlog('pid %d exited, status %d' % (pid, status))
         failures |= status
     print
     if not options.noskips:
         for s in skips:
             print "Skipped %s: %s" % (s[0], s[1])
     for s in fails:
         print "Failed %s: %s" % (s[0], s[1])
 
     _checkhglib("Tested")
     print "# Ran %d tests, %d skipped, %d failed." % (
         tested, skipped, failed)
 
     if options.anycoverage:
         outputcoverage(options)
     sys.exit(failures != 0)
 
 results = dict(p=[], f=[], s=[], i=[])
 resultslock = threading.Lock()
 iolock = threading.Lock()
 
 def runqueue(options, tests, results):
     for test in tests:
         ret = runone(options, test)
         if options.first and ret is not None and not ret:
             break
 
 def runtests(options, tests):
     global DAEMON_PIDS, HGRCPATH
     DAEMON_PIDS = os.environ["DAEMON_PIDS"] = os.path.join(HGTMP, 'daemon.pids')
     HGRCPATH = os.environ["HGRCPATH"] = os.path.join(HGTMP, '.hgrc')
 
     try:
         if INST:
             installhg(options)
             _checkhglib("Testing")
 
         if options.restart:
             orig = list(tests)
             while tests:
                 if os.path.exists(tests[0] + ".err"):
                     break
                 tests.pop(0)
             if not tests:
                 print "running all tests"
                 tests = orig
 
         runqueue(options, tests, results)
 
         failed = len(results['f'])
         tested = len(results['p']) + failed
         skipped = len(results['s'])
         ignored = len(results['i'])
 
         if options.child:
             fp = os.fdopen(options.child, 'w')
             fp.write('%d\n%d\n%d\n' % (tested, skipped, failed))
             for s in results['s']:
                 fp.write("%s %s\n" % s)
             for s in results['f']:
                 fp.write("%s %s\n" % s)
             fp.close()
         else:
             print
             for s in results['s']:
                 print "Skipped %s: %s" % s
             for s in results['f']:
                 print "Failed %s: %s" % s
             _checkhglib("Tested")
             print "# Ran %d tests, %d skipped, %d failed." % (
                 tested, skipped + ignored, failed)
 
         if options.anycoverage:
             outputcoverage(options)
     except KeyboardInterrupt:
         failed = True
         print "\ninterrupted!"
 
     if failed:
         sys.exit(1)
 
 def main():
     (options, args) = parseargs()
     if not options.child:
         os.umask(022)
 
         checktools()
 
     if len(args) == 0:
         args = os.listdir(".")
     args.sort()
 
     tests = args
 
     # Reset some environment variables to well-known values so that
     # the tests produce repeatable output.
     os.environ['LANG'] = os.environ['LC_ALL'] = os.environ['LANGUAGE'] = 'C'
     os.environ['TZ'] = 'GMT'
     os.environ["EMAIL"] = "Foo Bar <[e-mail]>"
     os.environ['CDPATH'] = ''
     os.environ['COLUMNS'] = '80'
     os.environ['GREP_OPTIONS'] = ''
     os.environ['http_proxy'] = ''
 
     # unset env related to hooks
     for k in os.environ.keys():
         if k.startswith('HG_'):
             # can't remove on solaris
             os.environ[k] = ''
             del os.environ[k]
 
     global TESTDIR, HGTMP, INST, BINDIR, PYTHONDIR, COVERAGE_FILE
     TESTDIR = os.environ["TESTDIR"] = os.getcwd()
     if options.tmpdir:
         options.keep_tmpdir = True
         tmpdir = options.tmpdir
         if os.path.exists(tmpdir):
             # Meaning of tmpdir has changed since 1.3: we used to create
             # HGTMP inside tmpdir; now HGTMP is tmpdir.  So fail if
             # tmpdir already exists.
             sys.exit("error: temp dir %r already exists" % tmpdir)
 
             # Automatically removing tmpdir sounds convenient, but could
             # really annoy anyone in the habit of using "--tmpdir=/tmp"
             # or "--tmpdir=$HOME".
             #vlog("# Removing temp dir", tmpdir)
             #shutil.rmtree(tmpdir)
         os.makedirs(tmpdir)
     else:
         tmpdir = tempfile.mkdtemp('', 'hgtests.')
     HGTMP = os.environ['HGTMP'] = os.path.realpath(tmpdir)
     DAEMON_PIDS = None
     HGRCPATH = None
 
     os.environ["HGEDITOR"] = sys.executable + ' -c "import sys; sys.exit(0)"'
     os.environ["HGMERGE"] = "internal:merge"
     os.environ["HGUSER"]   = "test"
     os.environ["HGENCODING"] = "ascii"
     os.environ["HGENCODINGMODE"] = "strict"
     os.environ["HGPORT"] = str(options.port)
     os.environ["HGPORT1"] = str(options.port + 1)
     os.environ["HGPORT2"] = str(options.port + 2)
 
     if options.with_hg:
         INST = None
         BINDIR = os.path.dirname(os.path.realpath(options.with_hg))
 
         # This looks redundant with how Python initializes sys.path from
         # the location of the script being executed.  Needed because the
         # "hg" specified by --with-hg is not the only Python script
         # executed in the test suite that needs to import 'mercurial'
         # ... which means it's not really redundant at all.
         PYTHONDIR = BINDIR
     else:
         INST = os.path.join(HGTMP, "install")
         BINDIR = os.environ["BINDIR"] = os.path.join(INST, "bin")
         PYTHONDIR = os.path.join(INST, "lib", "python")
 
     os.environ["BINDIR"] = BINDIR
     os.environ["PYTHON"] = PYTHON
 
     if not options.child:
         path = [BINDIR] + os.environ["PATH"].split(os.pathsep)
         os.environ["PATH"] = os.pathsep.join(path)
 
         # Include TESTDIR in PYTHONPATH so that out-of-tree extensions
         # can run .../tests/run-tests.py test-foo where test-foo
         # adds an extension to HGRC
         pypath = [PYTHONDIR, TESTDIR]
         # We have to augment PYTHONPATH, rather than simply replacing
         # it, in case external libraries are only available via current
         # PYTHONPATH.  (In particular, the Subversion bindings on OS X
         # are in /opt/subversion.)
         oldpypath = os.environ.get(IMPL_PATH)
         if oldpypath:
             pypath.append(oldpypath)
         os.environ[IMPL_PATH] = os.pathsep.join(pypath)
 
     COVERAGE_FILE = os.path.join(TESTDIR, ".coverage")
 
     vlog("# Using TESTDIR", TESTDIR)
     vlog("# Using HGTMP", HGTMP)
     vlog("# Using PATH", os.environ["PATH"])
     vlog("# Using", IMPL_PATH, os.environ[IMPL_PATH])
 
     try:
         if len(tests) > 1 and options.jobs > 1:
             runchildren(options, tests)
         else:
             runtests(options, tests)
     finally:
         time.sleep(1)
         cleanup(options)
 
 if __name__ == '__main__':
     main()