dependabot-news-md-autofill.yaml

name: Dependabot NEWS.md autofill

on:
pull_request:
  branches: [main]
  types: [opened, synchronize, reopened, edited]

permissions:
  contents: write
  pull-requests: read

jobs:
  add-news-entry:
    if: github.actor == 'dependabot[bot]'
    runs-on: ubuntu-latest

    steps:
      - name: Checkout base branch
        uses: actions/checkout@v6
        with:
          ref: main
          fetch-depth: 0

      - name: Compute NEWS.md entry from Dependabot title
        id: news
        shell: bash
        env:
          TITLE: ${{ github.event.pull_request.title }}
        run: |
          set -euo pipefail

          sanitize() {
            printf '%s' "$1" \
              | tr -d '\r\n' \
              | tr -cd '[:alnum:][:space:].,_@%:/+-' \
              | sed 's/[[:space:]]\+/ /g'
          }

          if [[ "$TITLE" =~ ^Bump[[:space:]]+(.+)[[:space:]]+from[[:space:]]+([^[:space:]]+)[[:space:]]+to[[:space:]]+([^[:space:]]+)$ ]]; then
            RAW_PKG="${BASH_REMATCH[1]}"
            RAW_FROM="${BASH_REMATCH[2]}"
            RAW_TO="${BASH_REMATCH[3]}"

            PKG="$(sanitize "$RAW_PKG")"
            FROM="$(sanitize "$RAW_FROM")"
            TO="$(sanitize "$RAW_TO")"

            ENTRY="* dependabot updating package ${PKG} from version ${FROM} to version ${TO} new"
          else
            ENTRY="* dependabot updating dependencies new"
          fi

          {
            echo "entry<<EOF"
            echo "$ENTRY"
            echo "EOF"
          } >> "$GITHUB_OUTPUT"

      - name: Update NEWS.md
        id: update
        shell: bash
        run: |
          set -euo pipefail

          ENTRY="${{ steps.news.outputs.entry }}"

          if [[ ! -f NEWS.md ]]; then
            echo "::error file=NEWS.md,line=1,col=1::NEWS.md not found."
            exit 1
          fi

          if grep -Fqx "$ENTRY" NEWS.md; then
            echo "changed=false" >> "$GITHUB_OUTPUT"
            exit 0
          fi

          tmp="$(mktemp)"

          awk -v entry="$ENTRY" '
            BEGIN { inserted=0 }
            {
              print $0
              if ($0 ~ /^##[[:space:]]+Features[[:space:]]*$/ && inserted == 0) {
                print entry
                inserted=1
              }
            }
            END {
              if (inserted == 0) {
                print ""
                print entry
              }
            }
          ' NEWS.md > "$tmp"

          mv "$tmp" NEWS.md

          echo "changed=true" >> "$GITHUB_OUTPUT"

      - name: Commit and push to PR branch
        if: steps.update.outputs.changed == 'true'
        shell: bash
        run: |
          set -euo pipefail

          git fetch origin "${{ github.event.pull_request.head.ref }}"
          git checkout "${{ github.event.pull_request.head.ref }}"

          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

          git add NEWS.md
          git commit -m "Update NEWS.md for Dependabot PR"
          git push origin HEAD