comparison mercurial/scmutil.py @ 16390:4df76d5506a9

scmutil: speed up revrange

This improves the performance of "hg log -l1" from 0.21 seconds to
0.07 on a Linux kernel tree.

Ideally we could use xrange instead of range on the most common
path, and thus avoid a ton of allocation, but xrange doesn't support
slice-based indexing.

16389:79fecd735d26

            return defval
        return repo[val].rev()

    seen, l = set(), []
    for spec in revs:
        # attempt to parse old-style ranges first to deal with
        # things like old-tag which contain query metacharacters
        try:
            if isinstance(spec, int):
                seen.add(spec)

            if _revrangesep in spec:
                start, end = spec.split(_revrangesep, 1)
                start = revfix(repo, start, 0)
                end = revfix(repo, end, len(repo) - 1)
                step = start > end and -1 or 1
                for rev in xrange(start, end + step, step):
                    if rev in seen:
                        continue
                    seen.add(rev)
                    l.append(rev)
                continue
            elif spec and spec in repo: # single unquoted rev
                rev = revfix(repo, spec, None)
                if rev in seen:
                    continue

16390:4df76d5506a9

            return defval
        return repo[val].rev()

    seen, l = set(), []
    for spec in revs:
        if l and not seen:
            seen = set(l)
        # attempt to parse old-style ranges first to deal with
        # things like old-tag which contain query metacharacters
        try:
            if isinstance(spec, int):
                seen.add(spec)

            if _revrangesep in spec:
                start, end = spec.split(_revrangesep, 1)
                start = revfix(repo, start, 0)
                end = revfix(repo, end, len(repo) - 1)
                step = start > end and -1 or 1
                if not seen and not l:
                    # by far the most common case: revs = ["-1:0"]
                    l = range(start, end + step, step)
                    # defer syncing seen until next iteration
                    continue
                newrevs = set(xrange(start, end + step, step))
                if seen:
                    newrevs.difference_update(seen)
                    seen.union(newrevs)
                else:
                    seen = newrevs
                l.extend(sorted(newrevs, reverse=start > end))
                continue
            elif spec and spec in repo: # single unquoted rev
                rev = revfix(repo, spec, None)
                if rev in seen:
                    continue