#!/usr/bin/env python3

# fsmonitor-run-tests.py - Run Mercurial tests with fsmonitor enabled

#

# Copyright 2017 Facebook, Inc.

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

#

# This is a wrapper around run-tests.py that spins up an isolated instance of

# Watchman and runs the Mercurial tests against it. This ensures that the global

# version of Watchman isn't affected by anything this test does.

import argparse

import contextlib

import json

import os

import shutil

import subprocess

import sys

import tempfile

import uuid

osenvironb = getattr(os, 'environb', os.environ)

if sys.version_info > (3, 5, 0):

    PYTHON3 = True

    xrange = range  # we use xrange in one place, and we'd rather not use range

    def _sys2bytes(p):

        return p.encode('utf-8')

elif sys.version_info >= (3, 0, 0):

    print(

        '%s is only supported on Python 3.5+ and 2.7, not %s'

        % (sys.argv[0], '.'.join(str(v) for v in sys.version_info[:3]))

    )

    sys.exit(70)  # EX_SOFTWARE from `man 3 sysexit`

else:

    PYTHON3 = False

    # In python 2.x, path operations are generally done using

    # bytestrings by default, so we don't have to do any extra

    # fiddling there. We define the wrapper functions anyway just to

    # help keep code consistent between platforms.

    def _sys2bytes(p):

        return p

def getparser():

    """Obtain the argument parser used by the CLI."""

    parser = argparse.ArgumentParser(

        description='Run tests with fsmonitor enabled.',

        epilog='Unrecognized options are passed to run-tests.py.',

    )

    # - keep these sorted

    # - none of these options should conflict with any in run-tests.py

    parser.add_argument(

        '--keep-fsmonitor-tmpdir',

        action='store_true',

        help='keep temporary directory with fsmonitor state',

    )

    parser.add_argument(

        '--watchman',

        help='location of watchman binary (default: watchman in PATH)',

        default='watchman',

    )

    return parser

@contextlib.contextmanager

def watchman(args):

    basedir = tempfile.mkdtemp(prefix='hg-fsmonitor')

    try:

        # Much of this configuration is borrowed from Watchman's test harness.

        cfgfile = os.path.join(basedir, 'config.json')

        # TODO: allow setting a config

        with open(cfgfile, 'w') as f:

            f.write(json.dumps({}))

        logfile = os.path.join(basedir, 'log')

        clilogfile = os.path.join(basedir, 'cli-log')

        if os.name == 'nt':

            sockfile = '\\\\.\\pipe\\watchman-test-%s' % uuid.uuid4().hex

        else:

            sockfile = os.path.join(basedir, 'sock')

        pidfile = os.path.join(basedir, 'pid')

        statefile = os.path.join(basedir, 'state')

        argv = [

            args.watchman,

            '--sockname',

            sockfile,

            '--logfile',

            logfile,

            '--pidfile',

            pidfile,

            '--statefile',

            statefile,

            '--foreground',

            '--log-level=2',  # debug logging for watchman

        ]

        envb = osenvironb.copy()

        envb[b'WATCHMAN_CONFIG_FILE'] = _sys2bytes(cfgfile)

        with open(clilogfile, 'wb') as f:

            proc = subprocess.Popen(

                argv, env=envb, stdin=None, stdout=f, stderr=f

            )

            try:

                yield sockfile

            finally:

                proc.terminate()

                proc.kill()

    finally:

        if args.keep_fsmonitor_tmpdir:

            print('fsmonitor dir available at %s' % basedir)

        else:

            shutil.rmtree(basedir, ignore_errors=True)

def run():

    parser = getparser()

    args, runtestsargv = parser.parse_known_args()

    with watchman(args) as sockfile:

        osenvironb[b'WATCHMAN_SOCK'] = _sys2bytes(sockfile)

        # Indicate to hghave that we're running with fsmonitor enabled.

        osenvironb[b'HGFSMONITOR_TESTS'] = b'1'

        runtestdir = os.path.dirname(__file__)

        runtests = os.path.join(runtestdir, 'run-tests.py')

        blacklist = os.path.join(runtestdir, 'blacklists', 'fsmonitor')

        runtestsargv.insert(0, runtests)

        runtestsargv.extend(

            [

                '--extra-config',

                'extensions.fsmonitor=',

                # specify fsmonitor.mode=paranoid always in order to force

                # fsmonitor extension execute "paranoid" code path

                #

                # TODO: make fsmonitor-run-tests.py accept specific options

                '--extra-config',

                'fsmonitor.mode=paranoid',

                '--blacklist',

                blacklist,

            ]

        )

        return subprocess.call(runtestsargv)

if __name__ == '__main__':

    sys.exit(run())