Bug: Add simple helper script for commiting a change to multiple branches
Status: Patch Available
Priority: Low
Created: 31/Mar/23 15:02

This is just a simple additional script which committers can use to help them merge commits, especially if the change applies to multiple Cassandra versions.

For example, for CASSANDRA-18153, which applies to 3.0..trunk, it generates the following commands, which then can be run manually:

{noformat}
git fetch origin
git fetch jacek-lewandowski



# jacek-lewandowski/CASSANDRA-18153-3.0 -> cassandra-3.0
# --------------------------------------------------------------------------------------------------------
git switch cassandra-3.0
git reset --hard origin/cassandra-3.0
git cherry-pick e7e9b42559 # e7e9b42559 Save host id to system.local and flush immediately after startup
git cherry-pick -n 99e96a4f95 && git commit -a --amend --no-edit # 99e96a4f95 fixes
git cherry-pick -n c63e3f29f1 && git commit -a --amend --no-edit # c63e3f29f1 DO NOT MERGE - CircleCI config
grep 'CASSANDRA-18153' CHANGES.txt || sed -E -i '/^[0-9]+\.[0-9]+/{s/.*/&\n\ * Save host id to system.local and flush immediately after startup (CASSANDRA-18153)/;:a;n;ba}' CHANGES.txt
git diff CHANGES.txt
git add CHANGES.txt
git commit --amend --no-edit
(git diff origin/cassandra-3.0..HEAD -- .circleci/ | git apply -R --index) && git commit -a --amend --no-edit # Remove all changes in .circleci directory if you need to
git diff --name-only origin/cassandra-3.0..HEAD # print a list of all changes files



# jacek-lewandowski/CASSANDRA-18153-3.11 -> cassandra-3.11
# --------------------------------------------------------------------------------------------------------
git switch cassandra-3.11
git reset --hard origin/cassandra-3.11
git merge -s ours --log --no-edit cassandra-3.0
git cherry-pick -n 79e7b90c8f && git commit -a --amend --no-edit # 79e7b90c8f Save host id to system.local and flush immediately after startup
git cherry-pick -n bdca4c384b && git commit -a --amend --no-edit # bdca4c384b fixes
git cherry-pick -n 45078e6793 && git commit -a --amend --no-edit # 45078e6793 DO NOT MERGE - CircleCI config
grep 'CASSANDRA-18153' CHANGES.txt || sed -E -i '/^Merged from 3.0/{s/.*/&\n\ * Save host id to system.local and flush immediately after startup (CASSANDRA-18153)/;:a;n;ba}' CHANGES.txt
git diff CHANGES.txt
git add CHANGES.txt
git commit --amend --no-edit
(git diff origin/cassandra-3.11..HEAD -- .circleci/ | git apply -R --index) && git commit -a --amend --no-edit # Remove all changes in .circleci directory if you need to
git diff --name-only origin/cassandra-3.11..HEAD # print a list of all changes files



# jacek-lewandowski/CASSANDRA-18153-4.0 -> cassandra-4.0
# --------------------------------------------------------------------------------------------------------
git switch cassandra-4.0
git reset --hard origin/cassandra-4.0
git merge -s ours --log --no-edit cassandra-3.11
git cherry-pick -n 2227c5c7af && git commit -a --amend --no-edit # 2227c5c7af Save host id to system.local and flush immediately after startup
git cherry-pick -n a71d4e3408 && git commit -a --amend --no-edit # a71d4e3408 DO NOT MERGE - CircleCI config
git cherry-pick -n 6dc53f4e97 && git commit -a --amend --no-edit # 6dc53f4e97 fixes
grep 'CASSANDRA-18153' CHANGES.txt || sed -E -i '/^Merged from 3.0/{s/.*/&\n\ * Save host id to system.local and flush immediately after startup (CASSANDRA-18153)/;:a;n;ba}' CHANGES.txt
git diff CHANGES.txt
git add CHANGES.txt
git commit --amend --no-edit
(git diff origin/cassandra-4.0..HEAD -- .circleci/ | git apply -R --index) && git commit -a --amend --no-edit # Remove all changes in .circleci directory if you need to
git diff --name-only origin/cassandra-4.0..HEAD # print a list of all changes files



# jacek-lewandowski/CASSANDRA-18153-4.1 -> cassandra-4.1
# --------------------------------------------------------------------------------------------------------
git switch cassandra-4.1
git reset --hard origin/cassandra-4.1
git merge -s ours --log --no-edit cassandra-4.0
git cherry-pick -n 3584d17b36 && git commit -a --amend --no-edit # 3584d17b36 Save host id to system.local and flush immediately after startup
git cherry-pick -n e7b2ca37e6 && git commit -a --amend --no-edit # e7b2ca37e6 DO NOT MERGE - CircleCI config
git cherry-pick -n 85f3049e90 && git commit -a --amend --no-edit # 85f3049e90 fixes
grep 'CASSANDRA-18153' CHANGES.txt || sed -E -i '/^Merged from 3.0/{s/.*/&\n\ * Save host id to system.local and flush immediately after startup (CASSANDRA-18153)/;:a;n;ba}' CHANGES.txt
git diff CHANGES.txt
git add CHANGES.txt
git commit --amend --no-edit
(git diff origin/cassandra-4.1..HEAD -- .circleci/ | git apply -R --index) && git commit -a --amend --no-edit # Remove all changes in .circleci directory if you need to
git diff --name-only origin/cassandra-4.1..HEAD # print a list of all changes files



# jacek-lewandowski/CASSANDRA-18153 -> trunk
# --------------------------------------------------------------------------------------------------------
git switch trunk
git reset --hard origin/trunk
git merge -s ours --log --no-edit cassandra-4.1
git cherry-pick -n 3b9fa1653e && git commit -a --amend --no-edit # 3b9fa1653e DO NOT MERGE - CircleCI config
git cherry-pick -n e1389f6196 && git commit -a --amend --no-edit # e1389f6196 Save host id to system.local and flush immediately after startup
grep 'CASSANDRA-18153' CHANGES.txt || sed -E -i '/^Merged from 3.0/{s/.*/&\n\ * Save host id to system.local and flush immediately after startup (CASSANDRA-18153)/;:a;n;ba}' CHANGES.txt
git diff CHANGES.txt
git add CHANGES.txt
git commit --amend --no-edit
(git diff origin/trunk..HEAD -- .circleci/ | git apply -R --index) && git commit -a --amend --no-edit # Remove all changes in .circleci directory if you need to
git diff --name-only origin/trunk..HEAD # print a list of all changes files



git push --atomic origin cassandra-3.0 cassandra-3.11 cassandra-4.0 cassandra-4.1 trunk -n
{noformat}

The generated script takes into account the following:
- a change can span multiple commits - all of the will be properly squashed (when running a script, you can comment out the commits you don't want to include)
- when commits leave .circleci directory modified, one of the last commands for each branch reverts those changes
- the script does its best to update CHANGED.txt properly, to confirm, it always displays the diff for CHANGES.txt

Note that, the script does not push anything, it just generates the script to be manually run by the committer. 

I'll appreciate if someone can run it on Mac so we know if there are some fixes needed for MacOS.