build-microzig.yml

name: Build Microzig

on:
  push:
    branches: [main]
    paths:
      - .github/**
      - build.zig*
      - tools/**
      - core/**
      - port/**
      - examples/**
  pull_request:
    branches: [main]
    paths:
      - build.zig*
      - tools/**
      - core/**
      - port/**
      - examples/**

jobs:
  build-microzig:
    if: |
      ${{ 
        ( github.event_name == 'pull_request' && github.base_ref == 'main' ) 
        || github.ref_name == 'main' 
      }}
    name: Build
    uses: ./.github/workflows/build-base.yml
    with:
      zig-version: ${{ vars.MZ_TARGET_ZIG_VERSION }}
      get-submodules: true
      is-packaged: true
      zig-args: -Doptimize=ReleaseSmall
    secrets:
      downloads-url: ${{ secrets.DOWNLOADS_URL }}
  # If this is a push to main we want to create an automatic test against the
  # zig-master branch. To do this, we need to create a PR and while we could
  # just go directly from main to zig-master, this would mean that if the tests
  # with zig-master fail, the main branch will also display the failure (this
  # is because github action results are saved based on the commit). To solve
  # that issue, we create a new branch with a new commit in it, then create
  # the PR based on that.
  #
  # Creates the branch that we will use for the PR to zig-master
  create-branch:
    if: ${{ github.event_name == 'push' && github.ref_name == 'main' }}
    name: Create Patch Branch
    needs:
      - build-microzig
    runs-on: ubuntu-latest
    outputs:
      branch: master-patch/${{ github.sha }}
    permissions:
      contents: write
      pull-requests: write
    steps:
      # First we checkout the repository
      - uses: actions/checkout@v4
      # Check if the branch exsits. This will be used in future steps to
      # conditionally execute them.
      - id: cbe
        name: Check branch exists
        # The list remote returns nothing if the branch does not exist.
        # So, if there is nothing in the command output, it does not exist
        run: |
          if [[ -z "$(git ls-remote \
                        --heads origin master-patch/${{ github.sha }})" ]]; then
            echo "exists=false" >> "$GITHUB_OUTPUT"
          else
            echo "exists=true" >> "$GITHUB_OUTPUT"
          fi
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      # If the branch doesn't already exist, we create a new one. We use the
      # username and email of the last commit.
      - name: Create Branch
        if: steps.cbe.outputs.exists == 'false'
        run: |
          git config user.name "$(git log -1 --pretty=format:'%an')"
          git config user.email "$(git log -1 --pretty=format:'%ae')"
          git checkout -b "master-patch/${{ github.sha }}"
          git push -u origin "master-patch/${{ github.sha }}"
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      # Checkout to the new branch
      - name: checkout
        uses: actions/checkout@v4
        with:
          ref: master-patch/${{ github.sha }}
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      # Create an empty commit that will be used to save the ci results
      # against (For more details see "create-branch" comment)
      - name: add-commit
        run: |
          git config user.name "$(git log -1 --pretty=format:'%an')"
          git config user.email "$(git log -1 --pretty=format:'%ae')"
          git commit \
            --author "ZEG Github Action <>" \
            -m "chore: commit for zig master build ci" \
            --allow-empty
          git push
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
  # Now that a branch exists, we can create our PR. To do this we will use the
  # github command line tool.
  create-pr:
    if: ${{ github.event_name == 'push' && github.ref_name == 'main' }}
    name: Create Pull Request
    runs-on: ubuntu-latest
    needs: create-branch
    permissions:
      pull-requests: read
      contents: read
    steps:
      - uses: actions/checkout@v4
      # Check if the PR already exists, this will be used to conditionally
      # create the PR.
      - id: cpe
        name: check pr exists
        # github actions pr only outputs when the query find something.
        # So, if the output is empty, pr does not exist
        run: |
          gh pr list -B zig-master \
            -H "${{ needs.create-branch.outputs.branch }}" 2> check-exists-out
          if [[ -z "$(cat check-exists-out)" ]]; then 
            echo "exists=false" >> "$GITHUB_OUTPUT"
          else
            echo "exists=true" >> "$GITHUB_OUTPUT"
          fi
          cat check-exists-out
          rm check-exists-out
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      # Create the actual PR if it doesn't already exist
      - name: create pull request,
        if: steps.cpe.outputs.exists == 'false'
        run: |
          gh pr create -B zig-master -H master-patch/${{ github.sha }} \
            --title 'Testing commit ${{ github.sha }} with zig master' \
            --body 'Created by Github action'
        env:
          # We use a custom TOKEN to enable triggering other workflows.
          # See: https://docs.github.com/en/actions/writing-workflows/choosing-when-your-workflow-runs/triggering-a-workflow#triggering-a-workflow-from-a-workflow
          GITHUB_TOKEN: ${{ secrets.PR_CREATE_TOKEN }}