tests/test-duplicateoptions.py

merge-tools: allow marking a mergetool as completely disabled

Very often in my life I'm finding that the only configured merge tool
present on the system is vimdiff[0], and it's currently impossible (as
far as I can tell) short of specifying `ui.merge = `[1] to actually
*disable* a merge tool. This allows vimdiff-haters to put:

  [merge-tools]
  vimdiff.disable = yes

in their ~/.hgrc and never see vimdiff again. I'm stopping short of
putting this as a commented out entry in the sample new user hgrc
(seen when a user runs `hg config --edit` with no ~/.hgrc) for now,
but I might come back and do that later.

0: vimdiff is at an awkward intersection: it's usually installed by
the vim package which is often installed as a vi substitute, so it's
mere presence doesn't imply me wanting it, unlike (say) kdiff3.

1: There's a related problem I ran into today where specifying
`ui.merge = :merge` failed because :merge isn't a command, which I
think is a regression. I'll try and figure that out and at least file
a bug.

import os
from mercurial import ui, commands, extensions

ignore = set(['highlight', 'win32text', 'factotum'])

if os.name != 'nt':
    ignore.add('win32mbcs')

disabled = [ext for ext in extensions.disabled().keys() if ext not in ignore]

hgrc = open(os.environ["HGRCPATH"], 'w')
hgrc.write('[extensions]\n')

for ext in disabled:
    hgrc.write(ext + '=\n')

hgrc.close()

u = ui.ui()
extensions.loadall(u)

globalshort = set()
globallong = set()
for option in commands.globalopts:
    option[0] and globalshort.add(option[0])
    option[1] and globallong.add(option[1])

for cmd, entry in commands.table.iteritems():
    seenshort = globalshort.copy()
    seenlong = globallong.copy()
    for option in entry[1]:
        if (option[0] and option[0] in seenshort) or \
           (option[1] and option[1] in seenlong):
            print "command '" + cmd + "' has duplicate option " + str(option)
        seenshort.add(option[0])
        seenlong.add(option[1])