comparison mercurial/revlogutils/deltas.py @ 39520:5aef5afa8654

snapshot: refine candidate snapshot base upward

Once we found a suitable snapshot base it is useful to check if it has a
"children" snapshot that would provide a better diff. This is useful when base
not directly related to stored revision are picked. In those case, we "jumped"
to this new chain at an arbitrary point, checking if a higher point is more
appropriate will help to provide better results and increase snapshot reuse.

39519:e4d4361d0bcd

            previous = good
            base = revlog.deltaparent(good)
            if base == nullrev:
                break
            good = yield (base,)
    # we have found nothing
    yield None

def _rawgroups(revlog, p1, p2, cachedelta):
    """Provides group of revision to be tested as delta base

39520:5aef5afa8654

            previous = good
            base = revlog.deltaparent(good)
            if base == nullrev:
                break
            good = yield (base,)
        # refine snapshot up
        #
        # XXX the _findsnapshots call can be expensive and is "duplicated" with
        # the one done in `_rawgroups`. Once we start working on performance,
        # we should make the two logics share this computation.
        snapshots = collections.defaultdict(list)
        _findsnapshots(revlog, snapshots, good + 1)
        previous = None
        while good != previous:
            previous = good
            children = tuple(sorted(c for c in snapshots[good]))
            good = yield children

    # we have found nothing
    yield None

def _rawgroups(revlog, p1, p2, cachedelta):
    """Provides group of revision to be tested as delta base