comparison mercurial/revset.py @ 23787:678f53865c68

revset: use localrepo revbranchcache for branch name filtering

Branch name filtering in revsets was expensive. For every rev it created a
changectx and called .branch() which retrieved the branch name from the
changelog.

Instead, use the revbranchcache.

The revbranchcache is used read-only. The revset implementation with generators
and callbacks makes it hard to figure out when we are done using/updating the
cache and could write it back. It would also be 'tricky' to lock the repo for
writing from within a revset execution. Finally, the branchmap update will
usually make sure that the cache is updated before any revset can be run.
The revbranchcache is used without any locking but is short-lived and used in a
tight loop where we can assume that the changelog doesn't change ... or where
it not is relevant to us if it does.

perfrevset 'branch(mobile)' on mozilla-central.
Before:
! wall 10.989637 comb 10.970000 user 10.940000 sys 0.030000 (best of 3)
After, no cache:
! wall 7.368656 comb 7.370000 user 7.360000 sys 0.010000 (best of 3)
After, with cache:
! wall 0.528098 comb 0.530000 user 0.530000 sys 0.000000 (best of 18)

The performance improvement even without cache come from being based on
branchinfo on the changelog instead of using ctx.branch().

Some tests are added to verify that the revbranchcache works and keep an eye on
when the cache files actually are updated.

23786:7d63398fbfd1

    If `string` starts with `re:`, the remainder of the name is treated as
    a regular expression. To match a branch that actually starts with `re:`,
    use the prefix `literal:`.
    """
    try:
        b = getstring(x, '')
    except error.ParseError:
        # not a string, but another revspec, e.g. tip()
        pass

        kind, pattern, matcher = _stringmatcher(b)
        if kind == 'literal':
            # note: falls through to the revspec case if no branch with
            # this name exists
            if pattern in repo.branchmap():
                return subset.filter(lambda r: matcher(repo[r].branch()))
        else:
            return subset.filter(lambda r: matcher(repo[r].branch()))

    s = getset(repo, spanset(repo), x)
    b = set()
    for r in s:
        b.add(repo[r].branch())
    c = s.__contains__
    return subset.filter(lambda r: c(r) or repo[r].branch() in b)

def bumped(repo, subset, x):
    """``bumped()``
    Mutable changesets marked as successors of public changesets.

23787:678f53865c68

    If `string` starts with `re:`, the remainder of the name is treated as
    a regular expression. To match a branch that actually starts with `re:`,
    use the prefix `literal:`.
    """
    import branchmap
    urepo = repo.unfiltered()
    ucl = urepo.changelog
    getbi = branchmap.revbranchcache(urepo).branchinfo

    try:
        b = getstring(x, '')
    except error.ParseError:
        # not a string, but another revspec, e.g. tip()
        pass

        kind, pattern, matcher = _stringmatcher(b)
        if kind == 'literal':
            # note: falls through to the revspec case if no branch with
            # this name exists
            if pattern in repo.branchmap():
                return subset.filter(lambda r: matcher(getbi(ucl, r)[0]))
        else:
            return subset.filter(lambda r: matcher(getbi(ucl, r)[0]))

    s = getset(repo, spanset(repo), x)
    b = set()
    for r in s:
        b.add(getbi(ucl, r)[0])
    c = s.__contains__
    return subset.filter(lambda r: c(r) or getbi(ucl, r)[0] in b)

def bumped(repo, subset, x):
    """``bumped()``
    Mutable changesets marked as successors of public changesets.