trydiff: move check for quietness out of diffline()
By moving the condition out of diffline(), the call site becomes
clearer and diffline() no longer closes on any variables.
Note that this changes the value of the header variable from [''] to
[], but there is no difference in how these two are treated by the
following code. The new value seems more natural anyway.
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'])
d.clear()
printifpresent(d, ['b', 'c', 'd', 'e', 'f'])
if __name__ == '__main__':
test_lrucachedict()