crossval.yml

name: crossval

# Cross-validation runs the JS engine against a Python reference implementation.
# The Python sibling lives in the CPP _cpp_common skills suite (not yet
# open-source). This workflow verifies the test harness mechanically; the
# Python reference must be supplied as a workflow secret or skipped.

on:
  push:
    branches: [main, master]
  pull_request:
    branches: [main, master]
  workflow_dispatch:

jobs:
  crossval:
    name: JS-Python crossval
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-node@v4
        with:
          node-version: '20'

      - uses: actions/setup-python@v5
        with:
          python-version: '3.11'

      - name: Check for Python reference
        id: check_ref
        shell: bash
        run: |
          if [ -f "python_reference/cpm.py" ]; then
            echo "available=true" >> "$GITHUB_OUTPUT"
          else
            echo "available=false" >> "$GITHUB_OUTPUT"
            echo "::warning::Python reference (python_reference/cpm.py) not present in this repo."
            echo "::warning::Crossval will be skipped. Provide the reference to enable bit-identical parity checks."
          fi

      - name: Run crossval
        if: steps.check_ref.outputs.available == 'true'
        run: node cpm-engine.crossval.js

      - name: Verify engine version sync
        shell: bash
        run: |
          PKG_VER=$(node -p "require('./package.json').version")
          ENGINE_VER=$(node -p "require('./cpm-engine.js').ENGINE_VERSION")
          if [ "$PKG_VER" != "$ENGINE_VER" ]; then
            echo "::error::Version skew detected. package.json=$PKG_VER engine=$ENGINE_VER"
            exit 1
          fi
          echo "Versions agree: v$PKG_VER"