#!/usr/bin/env python
#
# run-tests.py - Run a set of tests on Mercurial
#
# Copyright 2006 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.

# 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)
#
# (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.)

import difflib
import errno
import optparse
import os
import subprocess
import shutil
import signal
import sys
import tempfile
import time

closefds = os.name == 'posix'
def Popen4(cmd, bufsize=-1):
    p = subprocess.Popen(cmd, shell=True, bufsize=bufsize,
                         close_fds=closefds,
                         stdin=subprocess.PIPE, stdout=subprocess.PIPE,
                         stderr=subprocess.STDOUT)
    p.fromchild = p.stdout
    p.tochild = p.stdin
    p.childerr = p.stderr
    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

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]")
    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("-f", "--first", action="store_true",
        help="exit on the first test failure")
    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"
             " (best used with --tmpdir)")
    parser.add_option("-R", "--restart", action="store_true",
        help="restart at last error")
    parser.add_option("-p", "--port", type="int",
        help="port on which servers should listen"
             " (default: $%s or %d)" % defaults['port'])
    parser.add_option("-r", "--retest", action="store_true",
        help="retest failed tests")
    parser.add_option("-s", "--cover_stdlib", action="store_true",
        help="print a test coverage report inc. standard libraries")
    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")
    parser.add_option("-v", "--verbose", action="store_true",
        help="output verbose messages")
    parser.add_option("-n", "--nodiff", action="store_true",
        help="skip showing test changes")
    parser.add_option("--with-hg", type="string",
        metavar="HG",
        help="test using specified hg script rather than a "
             "temporary installation")
    parser.add_option("--local", action="store_true",
        help="shortcut for --with-hg=<testdir>/../hg")
    parser.add_option("--pure", action="store_true",
        help="use pure Python code instead of C extensions")

    for option, default in defaults.items():
        defaults[option] = int(os.environ.get(*default))
    parser.set_defaults(**defaults)
    (options, args) = parser.parse_args()

    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.cover_stdlib or
                           options.annotate)

    if options.anycoverage and options.with_hg:
        # I'm not sure if this is a fundamental limitation or just a
        # bug.  But I don't want to waste people's time and energy doing
        # test runs that don't give the results they want.
        parser.error("sorry, coverage options do not work when --with-hg "
                     "or --local 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
    else:
        vlog = lambda *msg: None

    if options.jobs < 1:
        print >> sys.stderr, 'ERROR: -j/--jobs must be positive'
        sys.exit(1)
    if options.interactive and options.jobs > 1:
        print '(--interactive overrides --jobs)'
        options.jobs = 1

    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):
    for line in difflib.unified_diff(expected, output,
            "Expected output", "Test output"):
        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 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)
    cmd = ('%s setup.py %s clean --all'
           ' install --force --prefix="%s" --install-lib="%s"'
           ' --install-scripts="%s" >%s 2>&1'
           % (sys.executable, pure, INST, PYTHONDIR, BINDIR, 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.anycoverage:
        vlog("# Installing coverage wrapper")
        os.environ['COVERAGE_FILE'] = COVERAGE_FILE
        if os.path.exists(COVERAGE_FILE):
            os.unlink(COVERAGE_FILE)
        # Create a wrapper script to invoke hg via coverage.py
        os.rename(os.path.join(BINDIR, "hg"), os.path.join(BINDIR, "_hg.py"))
        f = open(os.path.join(BINDIR, 'hg'), 'w')
        f.write('#!' + sys.executable + '\n')
        f.write('import sys, os; os.execv(sys.executable, [sys.executable, '
                '"%s", "-x", "-p", "%s"] + sys.argv[1:])\n' %
                (os.path.join(TESTDIR, 'coverage.py'),
                 os.path.join(BINDIR, '_hg.py')))
        f.close()
        os.chmod(os.path.join(BINDIR, 'hg'), 0700)

def outputcoverage(options):

    vlog('# Producing coverage report')
    os.chdir(PYTHONDIR)

    def covrun(*args):
        start = sys.executable, os.path.join(TESTDIR, 'coverage.py')
        cmd = '"%s" "%s" %s' % (start[0], start[1], ' '.join(args))
        vlog('# Running: %s' % cmd)
        os.system(cmd)

    omit = [BINDIR, TESTDIR, PYTHONDIR]
    if not options.cover_stdlib:
        # Exclude as system paths (ignoring empty strings seen on win)
        omit += [x for x in sys.path if x != '']
    omit = ','.join(omit)

    covrun('-c') # combine from parallel processes
    for fn in os.listdir(TESTDIR):
        if fn.startswith('.coverage.'):
            os.unlink(os.path.join(TESTDIR, fn))

    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)

class Timeout(Exception):
    pass

def alarmed(signum, frame):
    raise Timeout

def run(cmd, options):
    """Run command in a sub-process, capturing the output (stdout and stderr).
    Return the exist code, and output."""
    # TODO: Use subprocess.Popen if we're running on Python 2.4
    if os.name == 'nt' or sys.platform.startswith('java'):
        tochild, fromchild = os.popen4(cmd)
        tochild.close()
        output = fromchild.read()
        ret = fromchild.close()
        if ret == None:
            ret = 0
    else:
        proc = Popen4(cmd)
        try:
            output = ''
            proc.tochild.close()
            output = proc.fromchild.read()
            ret = proc.wait()
            if os.WIFEXITED(ret):
                ret = os.WEXITSTATUS(ret)
        except Timeout:
            vlog('# Process %d timed out - killing it' % proc.pid)
            os.kill(proc.pid, signal.SIGTERM)
            ret = proc.wait()
            if ret == 0:
                ret = signal.SIGTERM << 8
            output += ("\n### Abort: timeout after %d seconds.\n"
                       % options.timeout)
    return ret, splitnewlines(output)

def runone(options, test, skips, fails):
    '''tristate output:
    None -> skipped
    True -> passed
    False -> failed'''

    def skip(msg):
        if not options.verbose:
            skips.append((test, msg))
        else:
            print "\nSkipping %s: %s" % (test, msg)
        return None

    def fail(msg):
        fails.append((test, msg))
        if not options.nodiff:
            print "\nERROR: %s %s" % (test, msg)
        return None

    vlog("# Test", test)

    # create a fresh hgrc
    hgrc = file(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')
    hgrc.close()

    err = os.path.join(TESTDIR, test+".err")
    ref = os.path.join(TESTDIR, test+".out")
    testpath = os.path.join(TESTDIR, test)

    if os.path.exists(err):
        os.remove(err)       # Remove any previous output files

    # Make a tmp subdirectory to work in
    tmpd = os.path.join(HGTMP, test)
    os.mkdir(tmpd)
    os.chdir(tmpd)

    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':
        cmd = '%s "%s"' % (PYTHON, testpath)
    elif lctest.endswith('.bat'):
        # do not run batch scripts on non-windows
        if os.name != 'nt':
            return skip("batch script")
        # To reliably get the error code from batch files on WinXP,
        # the "cmd /c call" prefix is needed. Grrr
        cmd = 'cmd /c call "%s"' % testpath
    else:
        # do not run shell scripts on windows
        if os.name == 'nt':
            return skip("shell script")
        # do not try to run non-executable programs
        if not os.path.exists(testpath):
            return fail("does not exist")
        elif not os.access(testpath, os.X_OK):
            return skip("not executable")
        cmd = '"%s"' % testpath

    if options.timeout > 0:
        signal.alarm(options.timeout)

    vlog("# Running", cmd)
    ret, out = run(cmd, options)
    vlog("# Ret was:", ret)

    if options.timeout > 0:
        signal.alarm(0)

    mark = '.'

    skipped = (ret == SKIPPED_STATUS)
    # If reference output file exists, check test output against it
    if os.path.exists(ref):
        f = open(ref, "r")
        refout = splitnewlines(f.read())
        f.close()
    else:
        refout = []
    if skipped:
        mark = 's'
        missing, failed = parsehghaveoutput(out)
        if not missing:
            missing = ['irrelevant']
        if failed:
            fail("hghave failed checking for %s" % failed[-1])
            skipped = False
        else:
            skip(missing[-1])
    elif out != refout:
        mark = '!'
        if ret:
            fail("output changed and returned error code %d" % ret)
        else:
            fail("output changed")
        if not options.nodiff:
            showdiff(refout, out)
        ret = 1
    elif ret:
        mark = '!'
        fail("returned error code %d" % ret)

    if not options.verbose:
        sys.stdout.write(mark)
        sys.stdout.flush()

    if ret != 0 and not skipped:
        # Save errors to a file for diagnosis
        f = open(err, "wb")
        for line in out:
            f.write(line)
        f.close()

    # Kill off any leftover daemon processes
    try:
        fp = file(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

    os.chdir(TESTDIR)
    if not options.keep_tmpdir:
        shutil.rmtree(tmpd, 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
    if optcopy['with_hg'] is None:
        optcopy['with_hg'] = os.path.join(BINDIR, "hg")
    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)]
        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)
    failures = 0
    tested, skipped, failed = 0, 0, 0
    skips = []
    fails = []
    while fps:
        pid, status = os.wait()
        fp = fps.pop(pid)
        l = fp.read().splitlines()
        test, skip, fail = map(int, l[:3])
        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
    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)
    sys.exit(failures != 0)

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.timeout > 0:
            try:
                signal.signal(signal.SIGALRM, alarmed)
                vlog('# Running each test with %d second timeout' %
                     options.timeout)
            except AttributeError:
                print 'WARNING: cannot run tests with timeouts'
                options.timeout = 0

        tested = 0
        failed = 0
        skipped = 0

        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

        skips = []
        fails = []
        for test in tests:
            if options.retest and not os.path.exists(test + ".err"):
                skipped += 1
                continue
            ret = runone(options, test, skips, fails)
            if ret is None:
                skipped += 1
            elif not ret:
                if options.interactive:
                    print "Accept this change? [n] ",
                    answer = sys.stdin.readline().strip()
                    if answer.lower() in "y yes".split():
                        rename(test + ".err", test + ".out")
                        tested += 1
                        fails.pop()
                        continue
                failed += 1
                if options.first:
                    break
            tested += 1

        if options.child:
            fp = os.fdopen(options.child, 'w')
            fp.write('%d\n%d\n%d\n' % (tested, skipped, failed))
            for s in skips:
                fp.write("%s %s\n" % s)
            for s in fails:
                fp.write("%s %s\n" % s)
            fp.close()
        else:
            print
            for s in skips:
                print "Skipped %s: %s" % s
            for s in fails:
                print "Failed %s: %s" % s
            _checkhglib("Tested")
            print "# Ran %d tests, %d skipped, %d failed." % (
                tested, skipped, 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()

    # Reset some environment variables to well-known values so that
    # the tests produce repeatable output.
    os.environ['LANG'] = os.environ['LC_ALL'] = 'C'
    os.environ['TZ'] = 'GMT'
    os.environ["EMAIL"] = "Foo Bar <foo.bar@example.com>"
    os.environ['CDPATH'] = ''

    global TESTDIR, HGTMP, INST, BINDIR, PYTHONDIR, COVERAGE_FILE
    TESTDIR = os.environ["TESTDIR"] = os.getcwd()
    HGTMP = os.environ['HGTMP'] = os.path.realpath(tempfile.mkdtemp('', 'hgtests.',
                                                   options.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('PYTHONPATH')
        if oldpypath:
            pypath.append(oldpypath)
        os.environ['PYTHONPATH'] = os.pathsep.join(pypath)

    COVERAGE_FILE = os.path.join(TESTDIR, ".coverage")

    if len(args) == 0:
        args = os.listdir(".")
        args.sort()

    tests = []
    for test in args:
        if (test.startswith("test-") and '~' not in test and
            ('.' not in test or test.endswith('.py') or
             test.endswith('.bat'))):
            tests.append(test)
    if not tests:
        print "# Ran 0 tests, 0 skipped, 0 failed."
        return

    vlog("# Using TESTDIR", TESTDIR)
    vlog("# Using HGTMP", HGTMP)
    vlog("# Using PATH", os.environ["PATH"])
    vlog("# Using PYTHONPATH", os.environ["PYTHONPATH"])

    try:
        if len(tests) > 1 and options.jobs > 1:
            runchildren(options, tests)
        else:
            runtests(options, tests)
    finally:
        cleanup(options)

main()
