Feedback #330

	name: Enforce Semi-Linear Git History

	on:
	pull_request:
	types:
	- synchronize
	- opened
	- reopened

	jobs:
	check-semi-linear:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	with:
	ref: ${{ github.event.pull_request.head.sha }}
	fetch-depth: 0

	- name: Check if PR branches off from target-branch's latest commit
	run: \|
	# Get the target branch name
	TARGET_BRANCH=$(gh pr view ${PR_NUMBER} --json baseRefName -q '.baseRefName')

	# Script below is based on: https://stackoverflow.com/a/75369041/19221602
	# Check that all commits in TARGET_BRANCH..PR_BRANCH are descendants of TARGET_BRANCH
	BOUNDARY=$(git rev-list --boundary origin/${TARGET_BRANCH}..HEAD \| grep -e '^-')
	WANTED=$(git rev-parse origin/${TARGET_BRANCH})
	WANTED="-$WANTED"

	if [ "$BOUNDARY" != "$WANTED" ]; then
	echo "Error: You need to rebase on top of upstream/${TARGET_BRANCH}."
	exit 1
	fi

	echo "Your branch is properly rebased on top of upstream/${TARGET_BRANCH}."
	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
	PR_NUMBER: ${{ github.event.pull_request.number }}

Provide feedback