Junio C Hamano[PATCH] git-merge: preserve and merge local changes when doing fast forward
The idea and the logic are identical to what "checkout -m" does when switching the branches. Instead of refusing the two-way merge, perform the three-way merge between the old head, the working tree and the new head, and leave the (potentially conflicted) merge result in the working tree.
If this turns out to be a sane thing to do, we probably should make the common logic between "checkout -m" and this into a built-in command.
Signed-off-by: Junio C Hamano <junkio@cox.net> ---
* I am not sure if this is worth doing in general; it can leave a huge mess if the conflict with the merge and the local change is too extensive and does not give a good way to recover from it, and that is why we require an explicit "-m" to "git checkout" for this behaviour. Perhaps we would want a new option to git-merge to allow preserving the local changes, but the obvious candidate -m is taken for something else per recent popular request X-<...
git-merge.sh | 42 +++++++++++++++++++++++++++++++++++++++++- 1 files changed, 41 insertions(+), 1 deletions(-)
Show changes to git-merge.sh +41 −1
diff --git a/git-merge.sh b/git-merge.sh index 75af10d..324991f 100755 --- a/git-merge.sh +++ b/git-merge.sh @@ -91,6 +91,46 @@ finish () { esac } +merge_local_changes () { + merge_error=$(git-read-tree -m -u $1 $2 2>&1) || ( + # Match the index to the working tree, and do a three-way. + git diff-files --name-only | + git update-index --remove --stdin && + work=`git write-tree` && + git read-tree --reset -u $2 && + git read-tree -m -u --aggressive $1 $2 $work || exit + + echo >&2 "Carrying local changes forward." + if result=`git write-tree 2>/dev/null` + then + echo >&2 "Trivially automerged." + else + git merge-index -o git-merge-one-file -a + fi + + # Do not register the cleanly merged paths in the index + # yet; this is not a real merge before committing, but + # just carrying the working tree changes along. + unmerged=`git ls-files -u` + git read-tree --reset $2 + case "$unmerged" in + '') ;; + *) + ( + z40=0000000000000000000000000000000000000000 + echo "$unmerged" | + sed -e 's/^[0-7]* [0-9a-f]* /'"0 $z40 /" + echo "$unmerged" + ) | git update-index --index-info + + echo >&2 "Conflicts in locally modified files:" + git diff --name-only --diff-filter=U >&2 + ;; + esac + exit 0 + ) +} + case "$#" in 0) usage ;; esac rloga= have_message= @@ -264,7 +304,7 @@ f,*) echo "Updating $(git-rev-parse --short $head)..$(git-rev-parse --short $1)" git-update-index --refresh 2>/dev/null new_head=$(git-rev-parse --verify "$1^0") && - git-read-tree -u -v -m $head "$new_head" && + merge_local_changes $head $new_head && finish "$new_head" "Fast forward" dropsave exit 0
-- 1.4.4.1.gc419
