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.
#require symlink
$ origdir=`pwd`
$ hg init repo
$ cd repo
$ ln -s nothing dangling
avoid tar warnings about old timestamp
$ hg ci -d '2000-01-01 00:00:00 +0000' -qAm 'add symlink'
$ hg archive -t files ../archive
$ hg archive -t tar -p tar ../archive.tar
$ hg archive -t zip -p zip ../archive.zip
files
$ cd "$origdir"
$ cd archive
$ readlink.py dangling
dangling -> nothing
tar
$ cd "$origdir"
$ tar xf archive.tar
$ cd tar
$ readlink.py dangling
dangling -> nothing
zip
$ cd "$origdir"
$ unzip archive.zip > /dev/null 2>&1
$ cd zip
$ readlink.py dangling
dangling -> nothing
$ cd ..