view tests/hghave @ 20275:2123d27ff75d

backout: avoid update on simple case.

Before the changeset the backout process was:
1) go to <target>
2) revert to <target> parent
3) update back to changeset we came from

The two update steps can takes a very long time to move back and forth unrelated
file change between <target> and current working directory.

The new process is just merging current working directory with the parent of
<target> using <target> as ancestor. This give the very same result but skip
the two updates. On big repo with a lot of files and changes that save a lots of
time (x20 for one week window).

The "merge" version (hg backout --merge) is still done with upgrades. We could
imagine using in memory commit to speed it up but this is another fish.

#!/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 optparse
import sys
import hghave

checks = hghave.checks

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

def test_features():
    failed = 0
    for name, feature in checks.iteritems():
        check, _ = feature
        try:
            check()
        except Exception, 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")
parser.add_option("-q", "--quiet", action="store_true",
                  help="check features silently")

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

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

    quiet = options.quiet

    failures = 0

    def error(msg):
        global failures
        if not quiet:
            sys.stderr.write(msg + '\n')
        failures += 1

    for feature in args:
        negate = feature.startswith('no-')
        if negate:
            feature = feature[3:]

        if feature not in checks:
            error('skipped: unknown feature: ' + feature)
            sys.exit(2)

        check, desc = checks[feature]
        try:
            available = check()
        except Exception, e:
            error('hghave check failed: ' + feature)
            continue

        if not negate and not available:
            error('skipped: missing feature: ' + desc)
        elif negate and available:
            error('skipped: system supports %s' % desc)

    if failures != 0:
        sys.exit(1)