merge-kernel: Add support for reverts to apply as part of merge
In some cases, it may be necessary to revert one or more patches as part
of a merge. This can happen, for example, if bug fixes in the merged
branches conflict with each other, or if an API is changed differently
in both branches. This feature should only be used if reverts can not be
handled as separate commits.
BUG=b:183621345
TEST=Use script
Change-Id: Id31cb999b844a6007f3541d9df24d1530e1bec65
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/1733909
Reviewed-by: William K Lin <wklin@google.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Commit-Queue: Guenter Roeck <groeck@chromium.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
diff --git a/contrib/merge-kernel b/contrib/merge-kernel
index 94c6a06..6b99cf5 100755
--- a/contrib/merge-kernel
+++ b/contrib/merge-kernel
@@ -34,6 +34,8 @@
deadline=3 # Feedback deadline (in days, default 3).
changes=() # List of uncommitted CLs to be applied prior to merge.
patches=() # List of patches to apply before committing merge.
+reverts=() # List of patches to revert as part of merge, after merge
+prereverts=() # List of patches to revert as part of merge, prior to merge
dependency="" # No dependency
Subject="" # default subject
@@ -82,6 +84,10 @@
Must be existing local branch. Will be pushed into gerrit
as part of the merge process if not already available in
gerrit, and has to follow gerrit commit rules.
+ -P sha Revert patch <sha> as part of merge, pre-merge
+ May be repeated multiple times.
+ -R sha Revert patch <sha> as part of merge, post-merge
+ May be repeated multiple times.
-s Simulate, or dry-run. Don't actually push anything into
gerrit, and don't send e-mails.
-S subject Replace default subject line with provided string
@@ -162,7 +168,7 @@
local option
local vtag
- while getopts "b:c:d:fhl:npq:r:st:uS:x:" option; do
+ while getopts "b:c:d:fhl:nP:pq:r:R:st:uS:x:" option; do
case ${option} in
b) bugs="${OPTARG}" ;;
c) changeid="Change-Id: ${OPTARG}" ;;
@@ -177,6 +183,8 @@
p) prepare=1 ;;
q) dependency="${OPTARG}" ;;
r) rbranch="${OPTARG}" ;;
+ P) prereverts+=("${OPTARG}") ;;
+ R) reverts+=("${OPTARG}") ;;
t) tbranch="${OPTARG}" ;;
s) do_dryrun=1 ;;
S) Subject="${OPTARG}" ;;
@@ -615,6 +623,19 @@
done
}
+# Apply reverts from list of SHAs from merge branch prior to
+# the actual merge
+do_apply_reverts() {
+ local revert
+
+ for revert in $*; do
+ echo "Reverting commit ${revert}"
+ if ! git revert --no-commit "${revert}"; then
+ die "Failed to revert commit ${revert} in merge branch."
+ fi
+ done
+}
+
# Do the merge.
# - Create merge branch.
# - Merge.
@@ -628,6 +649,7 @@
local patch
local file
local files
+ local revert
git branch -D "${mbranch}" >/dev/null 2>&1
if ! git checkout -b "${mbranch}" "${ocbranch}"; then
@@ -640,6 +662,10 @@
xbranch="${chromeos}/${obranch}"
fi
+ if [[ -n "${prereverts[@]}" ]]; then
+ do_apply_reverts ${prereverts[@]}
+ fi
+
do_apply_changes
ref=$(git rev-parse HEAD)
@@ -682,6 +708,13 @@
die "Failed to commit merge."
fi
+ if [[ -n "${reverts[@]}" ]]; then
+ do_apply_reverts ${reverts[@]}
+ if ! git commit --amend --no-edit; then
+ die "Failed to commit merge after post-commit reverts."
+ fi
+ fi
+
# Update commit message.
( echo "${Subject}"
@@ -701,6 +734,19 @@
) >> "${tmpfile}"
fi
+ # Add reverts to description.
+ if [[ -n "${prereverts[@]}${reverts[@]}" ]]; then
+ (
+ echo "The following patches have been reverted as part of the merge"
+ echo "to remove code which is obsolete or no longer applicable."
+ echo
+ for revert in ${prereverts[@]} ${reverts[@]}; do
+ echo " $(git show --oneline --no-decorate -s ${revert})"
+ done
+ echo
+ ) >> "${tmpfile}"
+ fi
+
if [[ -n "$(git log --oneline "${tag}..${obranch}")" ]]; then
( echo "Changes applied on top of '${tag}' prior to merge:"
git log --oneline --no-decorate "${tag}..${obranch}" | \
