tests/hghave

dirstate: do not write an empty dirstate just for backup

This will get in the way when we get more strict about holding the lock when
writing the dirstate.

Instead, we simply don't copy dirstate files around if there are None at backup
time.

A couple of tests are impacted they no longer need to backup such "empty"
dirstate.

#!/usr/bin/env python
"""Test the running system for features availability. Exit with zero
if all features are there, non-zero otherwise. If a feature name is
prefixed with "no-", the absence of feature is tested.
"""


import hghave
import optparse
import os
import sys

checks = hghave.checks


def list_features():
    for name, feature in sorted(checks.items()):
        desc = feature[1]
        print(name + ':', desc)


def test_features():
    failed = 0
    for name, feature in checks.items():
        check, _ = feature
        try:
            check()
        except Exception as e:
            print("feature %s failed:  %s" % (name, e))
            failed += 1
    return failed


parser = optparse.OptionParser("%prog [options] [features]")
parser.add_option(
    "--test-features", action="store_true", help="test available features"
)
parser.add_option(
    "--list-features", action="store_true", help="list available features"
)


def _loadaddon():
    if 'TESTDIR' in os.environ:
        # loading from '.' isn't needed, because `hghave` should be
        # running at TESTTMP in this case
        path = os.environ['TESTDIR']
    else:
        path = '.'

    if not os.path.exists(os.path.join(path, 'hghaveaddon.py')):
        return

    sys.path.insert(0, path)
    try:
        import hghaveaddon

        assert hghaveaddon  # silence pyflakes
    except BaseException as inst:
        sys.stderr.write(
            'failed to import hghaveaddon.py from %r: %s\n' % (path, inst)
        )
        sys.exit(2)
    sys.path.pop(0)


if __name__ == '__main__':
    options, args = parser.parse_args()
    _loadaddon()
    if options.list_features:
        list_features()
        sys.exit(0)

    if options.test_features:
        sys.exit(test_features())

    hghave.require(args)