view tests/test-revlog-ancestry.py @ 20713:6a1a4c212d50

revset: improve head revset performance

Previously the head() revset would iterate over every item in the subset and
check if it was a head.  Since the subset is often the entire repo, this was
slow on large repos. Now we iterate over each item in the head list and check if
it's in the subset, which results in much less work.

hg log -r 'head()' on a large repo:
Before: 0.95s
After: 0.28s

import os
from mercurial import hg, ui, merge

u = ui.ui()

repo = hg.repository(u, 'test1', create=1)
os.chdir('test1')

def commit(text, time):
    repo.commit(text=text, date="%d 0" % time)

def addcommit(name, time):
    f = open(name, 'w')
    f.write('%s\n' % name)
    f.close()
    repo[None].add([name])
    commit(name, time)

def update(rev):
    merge.update(repo, rev, False, True, False)

def merge_(rev):
    merge.update(repo, rev, True, False, False)

if __name__ == '__main__':
    addcommit("A", 0)
    addcommit("B", 1)

    update(0)
    addcommit("C", 2)

    merge_(1)
    commit("D", 3)

    update(2)
    addcommit("E", 4)
    addcommit("F", 5)

    update(3)
    addcommit("G", 6)

    merge_(5)
    commit("H", 7)

    update(5)
    addcommit("I", 8)

    # Ancestors
    print 'Ancestors of 5'
    for r in repo.changelog.ancestors([5]):
        print r,

    print '\nAncestors of 6 and 5'
    for r in repo.changelog.ancestors([6, 5]):
        print r,

    print '\nAncestors of 5 and 4'
    for r in repo.changelog.ancestors([5, 4]):
        print r,

    print '\nAncestors of 7, stop at 6'
    for r in repo.changelog.ancestors([7], 6):
        print r,

    print '\nAncestors of 7, including revs'
    for r in repo.changelog.ancestors([7], inclusive=True):
        print r,

    print '\nAncestors of 7, 5 and 3, including revs'
    for r in repo.changelog.ancestors([7, 5, 3], inclusive=True):
        print r,

    # Descendants
    print '\n\nDescendants of 5'
    for r in repo.changelog.descendants([5]):
        print r,

    print '\nDescendants of 5 and 3'
    for r in repo.changelog.descendants([5, 3]):
        print r,

    print '\nDescendants of 5 and 4'
    for r in repo.changelog.descendants([5, 4]):
        print r,