git-revert with conflicts to behave as git-merge with conflicts

In a busy project, reverting a commit almost always results
in a conflict between one or more files (depending on the
commit being reverted).  It is useful to record this
conflict in the commit-to-be message of the resulting commit
(after the resolve).  The process now becomes:

git-revert <SHA-1>
<git complains and prints failed automatic>
<user manually resolves>
git-update-index <resolved files>
git-commit -s

And the commit message is now a merge of the revert commit
message and the conflict commit message, giving the user a
chance to edit it or add more information:

Signed-off-by: Luben Tuikov <ltuikov@yahoo.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-commit.sh

@@ -466,7 +466,7 @@ then
 elif test "$use_commit" != ""
 then
 	git-cat-file commit "$use_commit" | sed -e '1,/^$/d'
-elif test -f "$GIT_DIR/MERGE_HEAD" && test -f "$GIT_DIR/MERGE_MSG"
+elif test -f "$GIT_DIR/MERGE_MSG"
 then
 	cat "$GIT_DIR/MERGE_MSG"
 elif test -f "$GIT_DIR/SQUASH_MSG"
@@ -632,7 +632,7 @@ then
 	commit=$(cat "$GIT_DIR"/COMMIT_MSG | git-commit-tree $tree $PARENTS) &&
 	rlogm=$(sed -e 1q "$GIT_DIR"/COMMIT_MSG) &&
 	git-update-ref -m "$rloga: $rlogm" HEAD $commit "$current" &&
-	rm -f -- "$GIT_DIR/MERGE_HEAD" &&
+	rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" &&
 	if test -f "$NEXT_INDEX"
 	then
 		mv "$NEXT_INDEX" "$THIS_INDEX"

git-revert.sh

@@ -141,9 +141,18 @@ git-read-tree -m -u --aggressive $base $head $next &&
 result=$(git-write-tree 2>/dev/null) || {
     echo >&2 "Simple $me fails; trying Automatic $me."
     git-merge-index -o git-merge-one-file -a || {
+	    mv -f .msg "$GIT_DIR/MERGE_MSG"
+	    {
+		echo '
+Conflicts:
+'
+		git ls-files --unmerged |
+		sed -e 's/^[^	]*	/	/' |
+		uniq
+	    } >>"$GIT_DIR/MERGE_MSG"
 	    echo >&2 "Automatic $me failed.  After resolving the conflicts,"
 	    echo >&2 "mark the corrected paths with 'git-update-index <paths>'"
-	    echo >&2 "and commit with 'git commit -F .msg'"
+	    echo >&2 "and commit the result."
 	    case "$me" in
 	    cherry-pick)
 		echo >&2 "You may choose to use the following when making"