tests/test-ancestor.py

revset: don't recreate matcher for every revision

The matcher variable 'm' in checkstatus() is reset to None on each
call, so the caching of the matcher no longer happens as it was
intended. This seems to be a regression in ed7b674824a3 (revset: added
lazyset implementation to checkstatus, 2014-01-03).

Fix by moving the cached matcher into the enclosing function so it's
actually cached across calls. This speeds up

  hg log -r 'modifies(mercurial/context.py)' >/dev/null

from 7.5s to 4s.

Also see similar fix in f2aeff8a87b6 (revset: avoid recalculating
filesets, 2014-10-22).

from mercurial import ancestor, commands, hg, ui, util

# graph is a dict of child->parent adjacency lists for this graph:
# o  13
# |
# | o  12
# | |
# | | o    11
# | | |\
# | | | | o  10
# | | | | |
# | o---+ |  9
# | | | | |
# o | | | |  8
#  / / / /
# | | o |  7
# | | | |
# o---+ |  6
#  / / /
# | | o  5
# | |/
# | o  4
# | |
# o |  3
# | |
# | o  2
# |/
# o  1
# |
# o  0

graph = {0: [-1], 1: [0], 2: [1], 3: [1], 4: [2], 5: [4], 6: [4],
         7: [4], 8: [-1], 9: [6, 7], 10: [5], 11: [3, 7], 12: [9],
         13: [8]}
pfunc = graph.get

class mockchangelog(object):
    parentrevs = graph.get

def runmissingancestors(revs, bases):
    print "%% ancestors of %s and not of %s" % (revs, bases)
    print ancestor.missingancestors(revs, bases, pfunc)

def test_missingancestors():
    # Empty revs
    runmissingancestors([], [1])
    runmissingancestors([], [])

    # If bases is empty, it's the same as if it were [nullrev]
    runmissingancestors([12], [])

    # Trivial case: revs == bases
    runmissingancestors([0], [0])
    runmissingancestors([4, 5, 6], [6, 5, 4])

    # With nullrev
    runmissingancestors([-1], [12])
    runmissingancestors([12], [-1])

    # 9 is a parent of 12. 7 is a parent of 9, so an ancestor of 12. 6 is an
    # ancestor of 12 but not of 7.
    runmissingancestors([12], [9])
    runmissingancestors([9], [12])
    runmissingancestors([12, 9], [7])
    runmissingancestors([7, 6], [12])

    # More complex cases
    runmissingancestors([10], [11, 12])
    runmissingancestors([11], [10])
    runmissingancestors([11], [10, 12])
    runmissingancestors([12], [10])
    runmissingancestors([12], [11])
    runmissingancestors([10, 11, 12], [13])
    runmissingancestors([13], [10, 11, 12])

def genlazyancestors(revs, stoprev=0, inclusive=False):
    print ("%% lazy ancestor set for %s, stoprev = %s, inclusive = %s" %
           (revs, stoprev, inclusive))
    return ancestor.lazyancestors(mockchangelog, revs, stoprev=stoprev,
                                  inclusive=inclusive)

def printlazyancestors(s, l):
    print [n for n in l if n in s]

def test_lazyancestors():
    # Empty revs
    s = genlazyancestors([])
    printlazyancestors(s, [3, 0, -1])

    # Standard example
    s = genlazyancestors([11, 13])
    printlazyancestors(s, [11, 13, 7, 9, 8, 3, 6, 4, 1, -1, 0])

    # Standard with ancestry in the initial set (1 is ancestor of 3)
    s = genlazyancestors([1, 3])
    printlazyancestors(s, [1, -1, 0])

    # Including revs
    s = genlazyancestors([11, 13], inclusive=True)
    printlazyancestors(s, [11, 13, 7, 9, 8, 3, 6, 4, 1, -1, 0])

    # Test with stoprev
    s = genlazyancestors([11, 13], stoprev=6)
    printlazyancestors(s, [11, 13, 7, 9, 8, 3, 6, 4, 1, -1, 0])
    s = genlazyancestors([11, 13], stoprev=6, inclusive=True)
    printlazyancestors(s, [11, 13, 7, 9, 8, 3, 6, 4, 1, -1, 0])


# The C gca algorithm requires a real repo. These are textual descriptions of
# DAGs that have been known to be problematic.
dagtests = [
    '+2*2*2/*3/2',
    '+3*3/*2*2/*4*4/*4/2*4/2*2',
]
def test_gca():
    u = ui.ui()
    for i, dag in enumerate(dagtests):
        repo = hg.repository(u, 'gca%d' % i, create=1)
        cl = repo.changelog
        if not util.safehasattr(cl.index, 'ancestors'):
            # C version not available
            return

        commands.debugbuilddag(u, repo, dag)
        # Compare the results of the Python and C versions. This does not
        # include choosing a winner when more than one gca exists -- we make
        # sure both return exactly the same set of gcas.
        for a in cl:
            for b in cl:
                cgcas = sorted(cl.index.ancestors(a, b))
                pygcas = sorted(ancestor.ancestors(cl.parentrevs, a, b))
                if cgcas != pygcas:
                    print "test_gca: for dag %s, gcas for %d, %d:" % (dag, a, b)
                    print "  C returned:      %s" % cgcas
                    print "  Python returned: %s" % pygcas

if __name__ == '__main__':
    test_missingancestors()
    test_lazyancestors()
    test_gca()