asdf.sh

# Checkout the PR branch
echo "Checking out PR branch"
git checkout -q "${{ github.event.pull_request.head.ref }}"
echo "Github head ref is ${{ github.event.pull_request.head.ref }}"

# Find current branch name
echo "Finding current branch name"
CURRENT_BRANCH=$(git branch | grep ^\* | cut -d "*" -f 2 | cut -d " " -f 2)
echo "Current branch is $CURRENT_BRANCH"

# Find hash of commit most common ancestor, e.g. where branch began
echo "Finding hash of commit most common ancestor, e.g. where branch began"
BRANCH_MERGE_BASE=$(git merge-base ${BASE_BRANCH} ${CURRENT_BRANCH})
echo "Branch merge base is $BRANCH_MERGE_BASE"

# Find all commits since common ancestor
echo "Finding all commits since common ancestor"
BRANCH_COMMITS=$(git rev-list ${BRANCH_MERGE_BASE}..HEAD)
echo "Branch commits are $BRANCH_COMMITS"

# Find first commit, extract commit message and then Jira ticket number
FIRST_COMMIT=$(echo $BRANCH_COMMITS | head -n 1)
echo "First commit is $FIRST_COMMIT"

FIRST_COMMIT_MESSAGE=$(git log --max-count=1 --format=%B "$FIRST_COMMIT" | awk 'NF')
echo "First commit message is $FIRST_COMMIT_MESSAGE"

NORMALIZED_FIRST_COMMIT_MESSAGE=$(echo $FIRST_COMMIT_MESSAGE | tr '[:lower:]' '[:upper:]')
echo "Normalized first commit message is $NORMALIZED_FIRST_COMMIT_MESSAGE"

JIRA_TICKET=$(echo $NORMALIZED_FIRST_COMMIT_MESSAGE | grep -o -E '^[A-Z]{2,}-[0-9]+' || true)
echo "Jira ticket is $JIRA_TICKET"