Siddharth Agarwal <sid0@fb.com> [Sun, 11 Oct 2015 20:47:14 -0700] rev 26611
filemerge: break overall filemerge into separate premerge and merge steps
This means that in ms.resolve we must call merge after calling premerge. This
doesn't yet mean that all premerges happen before any merges -- however, this
does get us closer to our goal.
The output differences are because we recompute the merge tool. The only
user-visible difference caused by this patch is that if the tool is missing
we'll print the warning twice. Not a huge deal, though.
Siddharth Agarwal <sid0@fb.com> [Sun, 11 Oct 2015 20:04:40 -0700] rev 26610
filemerge: only copy to backup during premerge step
The premerge might leave the original file in an unclean state. Therefore it's
important to only copy the file in the beginning.
Siddharth Agarwal <sid0@fb.com> [Sun, 11 Oct 2015 20:02:53 -0700] rev 26609
filemerge: only print out "merging f" output at premerge step
We're soon going to call this function twice, once for premerge and once for
merge. This makes sure the "merging" output only gets printed during the
premerge step.