Resolving git conflicts for chained PRs after squash/merge commit

git-chain-conflicts.md

Assuming that there was a:

• PR1 based on branch main
• PR2 based on PR1

And after squash-merging PR1 into the main branch, sometimes we can't just merge PR2 due to a conflicts arising from the commits in PR1 being squashed.

Here's the step-by-step explanation of the Git workflow to resolve this issue:

1. git switch PR1 # if branch was deleted - restore it
2. Create a patch file that captures the changes made in PR2 relative to the state of the PR1, prior to merging it into main branch:

   git diff PR1..PR2 --full-index --binary > /tmp/diff.patch
   

3. Create a new branch resolve-conflicts:

   git switch -c resolve-conflicts
   

4. Apply the changes from PR2 to the resolve-conflicts branch:

   git apply /tmp/diff.patch
   

5. Create a single commit that combines all the changes from PR2:

   git commit -a -m "Merge commit"
   

6. git switch PR2
7. Merge the single commit created in step 5, which contains the changes from PR2, into the PR2 branch:

   git merge resolve-conflicts
   

After completing these steps, the actual main branch should now be mergeable into PR2 without conflicts.