param-guard.yml

name: Param guard

# Blocks pull requests that remove a parameter from a model that still exists.
# Removing a parameter is breaking: every Manifest user who already configured it
# loses the ability to see or change that setting.
#
# Override: a maintainer applies the `allow-param-removal` label to the PR. The
# label change re-triggers this workflow (see `types` below) and the guard step
# is skipped, leaving an auditable warning in the checks output.

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

jobs:
  no-param-removals:
    name: No parameter removals
    runs-on: ubuntu-latest
    steps:
      - name: Check out PR
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Fetch base branch
        run: git fetch --no-tags origin "${{ github.base_ref }}"

      - name: Set up Node
        uses: actions/setup-node@v4
        with:
          node-version: "20"
          cache: "npm"

      - name: Install dependencies
        run: npm ci

      - name: Guard against parameter removals
        if: ${{ !contains(github.event.pull_request.labels.*.name, 'allow-param-removal') }}
        run: npm run guard:params
        env:
          BASE_REF: "origin/${{ github.base_ref }}"

      - name: Removal override acknowledged
        if: ${{ contains(github.event.pull_request.labels.*.name, 'allow-param-removal') }}
        run: |
          echo "::warning::'allow-param-removal' label present — parameter-removal guard intentionally skipped for this PR."