tests/test-ancestor.py

hgweb: fix empty navigation detection

For some obscure reason, changelog.node(0) returns nullid if changelog is empty.
this break empty navigation detection. We fix this code by using the length of
the changelog.

Using the length have some issue with revision filtering but this is a small
step in the right direction. Proper fix comes in later changeset.

from mercurial import ancestor

# 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])

    # 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])

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