# check-macros.yml
#
# Verifies that every chapter-level copy of a macro file is byte-identical
# to its canonical version in macros/. Runs scripts/sync-macros.sh and
# fails the job if the script produced any change that was not already
# committed.
#
# Rationale: the repo ships one copy of each macro file per chapter so
# that each chapter directory remains self-contained on GitHub. Those
# copies are derived artifacts; macros/*.S is the single source of
# truth. This check turns "copies are in sync" from a convention into
# a machine-enforced invariant, so drift cannot sneak into main.
#
# To fix a failure locally:
#     ./scripts/sync-macros.sh
#     git add -u
#     git commit --amend --no-edit    # or a new commit, whichever you prefer

name: Check macro sync

on:
  push:
    branches: [main]
  pull_request:

jobs:
  check-macros:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Run sync script
        run: ./scripts/sync-macros.sh

      - name: Fail if any chapter copy drifted from canonical
        run: |
          if ! git diff --exit-code; then
            echo "::error::Chapter macro copies drifted from the canonical files in macros/."
            echo "::error::Run ./scripts/sync-macros.sh locally and commit the result."
            exit 1
          fi