tests/test-ancestor.py

revert: properly back up added files with local modification

These files were previously not backed up because the backup mechanism was not
smart enough. This leads to data lose for the user since uncommitted contents
were discarded.

We now properly move the modified version to <filename>.orig before deleting it.

We have to use a small hack to do a different action if "--no-backup" is
specified. This is needed because the backup process is actually a move (not a
copy) so the file is already missing when we backup. The internet kitten is a
bit disapointed about that, but such is life.

This patch concludes the "lets refactor revert" phases. We can now open the
"Lets find stupid bug with renames and merge" phases.

I'm sure that now that the code is clearer we could do it in another simpler
way, but I consider the current improvement good enough for now.

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()