# This workflow checks that there is either a 'pr/no-changelog' label applied to a PR
# or there is a changelog/<pr number>.txt file associated with a PR for a changelog entry

name: Check Changelog

on:
  pull_request:
    types: [opened, synchronize, labeled, unlabeled]
    # Runs on PRs to main
    branches:
      - main

jobs:
  # checks that a changelog entry is present for a PR
  changelog-check:
    # If there  a `pr/no-changelog` label we ignore this check
    if: "!contains(github.event.pull_request.labels.*.name, 'pr/no-changelog')"
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2
        with:
          ref: ${{ github.event.pull_request.head.sha }}
          fetch-depth: 0 # by default the checkout action doesn't checkout all branches
      - name: Check for changelog entry in diff
        run: |
          # check if there is a diff in the changelog directory
          changelog_files=$(git --no-pager diff --name-only HEAD "$(git merge-base HEAD "origin/${{ github.event.pull_request.base.ref }}")" -- changelog/${{ github.event.pull_request.number }}.txt)

          # If we do not find a file matching the PR # in changelog/, we fail the check
          if [ -z "$changelog_files" ]; then
            echo "Did not find a changelog entry named ${{ github.event.pull_request.number }}.txt"
            echo "If your changelog file is correct, skip this check with the 'pr/no-changelog' label"
            echo "Reference - https://github.com/hashicorp/vault/pull/10363 and https://github.com/hashicorp/vault/pull/11894"
            exit 1
          elif grep -q ':enhancement$' $changelog_files; then
            # "Enhancement is not a valid type of changelog entry, but it's a common mistake.
            echo "Found invalid type (enhancement) in changelog - did you mean improvement?"
            exit 1
          elif grep -q ':bugs$' $changelog_files; then
            echo "Found invalid type (bugs) in changelog - did you mean bug?"
            exit 1
          elif ! grep -q '```release-note:' $changelog_files; then
            # People often make changelog files like ```changelog:, which is incorrect.
            echo "Changelog file did not contain 'release-note' heading - check formatting."
            exit 1
          else
            echo "Found changelog entry in PR!"
          fi