tests/test-lrucachedict.py

chg: extract gethgcmd logic to a function

gethgcmd is to get original hg (not chg) binary name. This patch extracts
the logic from execcmdserver to make it available for the following patch.

from mercurial import util

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

    d.clear()
    printifpresent(d, ['b', 'c', 'd', 'e', 'f'])

    # Now test dicts that aren't full.
    d = util.lrucachedict(4)
    d['a'] = 1
    d['b'] = 2
    d['a']
    d['b']
    printifpresent(d, ['a', 'b'])

    # test copy method
    d = util.lrucachedict(4)
    d['a'] = 'va3'
    d['b'] = 'vb3'
    d['c'] = 'vc3'
    d['d'] = 'vd3'

    dc = d.copy()

    # all of these should be present
    print "\nAll of these should be present:"
    printifpresent(dc, ['a', 'b', 'c', 'd'], 'dc')

    # 'a' should be dropped because it was least recently used
    print "\nAll of these except 'a' should be present:"
    dc['e'] = 've3'
    printifpresent(dc, ['a', 'b', 'c', 'd', 'e'], 'dc')

    # contents and order of original dict should remain unchanged
    print "\nThese should be in reverse alphabetical order and read 'v?3':"
    dc['b'] = 'vb3_new'
    for k in list(iter(d)):
        print "d['%s']: %s" % (k, d[k])

if __name__ == '__main__':
    test_lrucachedict()