merge: use operation-provided labels (ex: dest/source) in several merge-tools
Tools that did not use labels already, used only one, or used some label other
than the exact strings of "local" or "other" were unmodified. Cases that used
the label "base" were modified as well, if they were otherwise changed in this
CL; "merged" was *not* changed.
There are other possible changes we might want to make, but I didn't:
- bcompare (linux and osx) uses the labels "parent1" and "parent2" instead of
"local" and "other", so it was left alone, even though beyondcompare3
(windows) *was* changed.
- araxis used the labels "Other", "Base", and "Local :$local", so it was also
left alone.
- UltraCompare didn't provide a label for 'local', just for 'base' and 'other',
so it was left alone.
Differential Revision: https://phab.mercurial-scm.org/D2012
#require execbit
$ hg init repo
$ cd repo
$ echo foo > foo
$ chmod 644 foo
$ hg ci -qAm '644'
$ chmod 755 foo
$ hg ci -qAm '755'
reverting to rev 0
$ hg revert -a -r 0
reverting foo
$ hg st
M foo
$ hg diff --git
diff --git a/foo b/foo
old mode 100755
new mode 100644
$ cd ..