[PATCH] mergetool--lib: specialize diff options for emerge and ecmerge

The ecmerge documentation mentions the following form:

	ecmerge --mode=diff2 $1 $2

Since git-difftool is about diffing, we should use that
instead of --mode=merge2.  Likewise, this drops the
$MERGED argument to emerge, as discussed on the git list
($gmane/117930).

Signed-off-by: David Aguilar <redacted>
---

I tested the emacs (emerge) bit, but I'm not an emacs
user and I didn't really see any difference with or
without the patch.  Dropping $MERGED seems like the
right thing to do nonetheless.

In emerge/emacs mode, we still end up seeing the
merge pane.  My emacs-fu is not sophisticated
enough to know how to inhibit the merge pane
(if that's even something we'd want to do).


Regarding ecmerge:  I found the --mode=diff2
flag by reading their documenation:

http://www.elliecomputing.com/OnlineDoc/ecmerge_EN/52335623.asp

I don't have ecmerge installed at all, so I'm just
going by the book on this one.  It *looks* correct,
and probably is, but let it be known that I
haven't tested the ecmerge snippet myself.

 git-mergetool--lib.sh |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index a16a279..8b5e6a8 100644
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh

@@ -228,8 +228,8 @@ run_merge_tool () {
 			fi
 			check_unchanged
 		else
-			"$merge_tool_path" "$LOCAL" "$REMOTE" \
-				--default --mode=merge2 --to="$MERGED"
+			"$merge_tool_path" --default --mode=diff2 \
+				"$LOCAL" "$REMOTE"
 		fi
 		;;
 	emerge)

@@ -248,7 +248,7 @@ run_merge_tool () {
 			status=$?
 		else
 			"$merge_tool_path" -f emerge-files-command \
-				"$LOCAL" "$REMOTE" "$(basename "$MERGED")"
+				"$LOCAL" "$REMOTE"
 		fi
 		;;
 	tortoisemerge)

-- 
1.6.3.rc3.40.g75b44