tests/test-lrucachedict.py

blackbox: add backup bundle paths to blackbox logs

Writes the backup bundle paths to the blackbox so it's easy to see which
backup bundle is associated with which command when you are debugging an
issue.

Example output:

2013/03/13 10:39:56 durham> strip tip
2013/03/13 10:39:59 durham> saved backup bundle to /data/users/durham/www-hg/.hg/strip-backup/e5fac262363a-backup.hg
2013/03/13 10:40:03 durham> strip tip exited 0 after 7.97 seconds

from mercurial import util

def printifpresent(d, xs):
    for x in xs:
        present = x in d
        print "'%s' in d: %s" % (x, present)
        if present:
            print "d['%s']: %s" % (x, d[x])

def test_lrucachedict():
    d = util.lrucachedict(4)
    d['a'] = 'va'
    d['b'] = 'vb'
    d['c'] = 'vc'
    d['d'] = 'vd'

    # all of these should be present
    printifpresent(d, ['a', 'b', 'c', 'd'])

    # 'a' should be dropped because it was least recently used
    d['e'] = 've'
    printifpresent(d, ['a', 'b', 'c', 'd', 'e'])

    # touch entries in some order (get or set).
    d['e']
    d['c'] = 'vc2'
    d['d']
    d['b'] = 'vb2'

    # 'e' should be dropped now
    d['f'] = 'vf'
    printifpresent(d, ['b', 'c', 'd', 'e', 'f'])

if __name__ == '__main__':
    test_lrucachedict()