resolveBuildRefs.yml

name: Resolve build refs

# Reusable workflow that resolves which Expensify/App and Expensify/Mobile-Expensify commits a build should check out.
#
# App head ref (APP_REF):
#   - The head SHA of the App PR (APP_PULL_REQUEST_URL), if provided.
#   - Otherwise, empty — callers fall back to the triggering ref (push commit / dispatch branch).
#
# Mobile-Expensify head ref (MOBILE_EXPENSIFY_REF), resolution order:
#   1. An explicit Mobile-Expensify PR URL (MOBILE_EXPENSIFY_PULL_REQUEST_URL), if provided.
#   2. Otherwise, if MOBILE_EXPENSIFY_MAIN is true, empty — callers build against Mobile-Expensify main.
#   3. Otherwise, a `MOBILE-EXPENSIFY: <pr-url>` entry in the body of the App PR (APP_PULL_REQUEST_URL),
#      If that PR is already merged, its head commit is stale, so Mobile-Expensify main (which contains the change) is used instead.
#   4. Otherwise, empty — callers fall back to the pinned submodule commit.
# Providing both MOBILE_EXPENSIFY_PULL_REQUEST_URL and MOBILE_EXPENSIFY_MAIN fails the run.
on:
  workflow_call:
    inputs:
      APP_PULL_REQUEST_URL:
        description: The Expensify/App pull request URL. Its description is scanned for a MOBILE-EXPENSIFY entry. Ignored if a Mobile-Expensify PR URL is provided.
        required: false
        type: string
        default: ''
      MOBILE_EXPENSIFY_PULL_REQUEST_URL:
        description: The Expensify/Mobile-Expensify pull request URL. Overrides MOBILE-EXPENSIFY set in the App PR description.
        required: false
        type: string
        default: ''
      MOBILE_EXPENSIFY_MAIN:
        description: Whether the caller builds against Mobile-Expensify main. Overrides MOBILE-EXPENSIFY set in the App PR description, and cannot be combined with MOBILE_EXPENSIFY_PULL_REQUEST_URL.
        required: false
        type: boolean
        default: false
    outputs:
      APP_PR_NUMBER:
        description: PR number extracted from the App PR URL (empty if none).
        value: ${{ jobs.resolve.outputs.APP_PR_NUMBER }}
      APP_REF:
        description: Resolved Expensify/App head SHA (empty to use the triggering ref).
        value: ${{ jobs.resolve.outputs.APP_REF }}
      MOBILE_EXPENSIFY_PR:
        description: Resolved Mobile-Expensify PR number (empty if none, including when MOBILE_EXPENSIFY_MAIN is true).
        value: ${{ jobs.resolve.outputs.MOBILE_EXPENSIFY_PR }}
      MOBILE_EXPENSIFY_REF:
        description: Resolved Mobile-Expensify head SHA, or `main` when the PR from the App PR description is already merged (empty to use the pinned submodule commit).
        value: ${{ jobs.resolve.outputs.MOBILE_EXPENSIFY_REF }}
    secrets:
      OS_BOTIFY_TOKEN:
        description: Token with read access to Expensify/Mobile-Expensify, used to resolve the PR head ref.
        required: true

jobs:
  resolve:
    name: Resolve build refs
    runs-on: 'blacksmith-4vcpu-ubuntu-2404'
    outputs:
      APP_PR_NUMBER: ${{ steps.extractAppPRNumber.outputs.PR_NUMBER }}
      APP_REF: ${{ steps.getAppHeadRef.outputs.REF }}
      MOBILE_EXPENSIFY_PR: ${{ steps.getHeadRef.outputs.PR }}
      MOBILE_EXPENSIFY_REF: ${{ steps.getHeadRef.outputs.REF }}
    steps:
      - name: Validate Mobile-Expensify inputs
        if: ${{ inputs.MOBILE_EXPENSIFY_PULL_REQUEST_URL != '' && inputs.MOBILE_EXPENSIFY_MAIN }}
        run: |
          echo "::error::❌ MOBILE_EXPENSIFY_PULL_REQUEST_URL and MOBILE_EXPENSIFY_MAIN cannot be used together. Provide a Mobile-Expensify PR URL to build against that PR, or set MOBILE_EXPENSIFY_MAIN to build against Mobile-Expensify main."
          exit 1

      - name: Extract App PR number from URL
        id: extractAppPRNumber
        if: ${{ inputs.APP_PULL_REQUEST_URL != '' }}
        run: |
          PR_NUMBER=$(echo '${{ inputs.APP_PULL_REQUEST_URL }}' | sed -E 's|.*/pull/([0-9]+).*|\1|')
          if ! [[ "$PR_NUMBER" =~ ^[0-9]+$ ]]; then
            echo "::error::❌ Could not extract PR number from the App PR URL. Please provide a valid GitHub PR URL (e.g., https://github.com/Expensify/App/pull/12345)"
            exit 1
          fi
          echo "PR_NUMBER=$PR_NUMBER" >> "$GITHUB_OUTPUT"

      - name: Resolve App head ref from PR number
        id: getAppHeadRef
        if: ${{ steps.extractAppPRNumber.outputs.PR_NUMBER != '' }}
        run: |
          set -e
          echo "REF=$(gh pr view ${{ steps.extractAppPRNumber.outputs.PR_NUMBER }} -R Expensify/App --json headRefOid --jq '.headRefOid')" >> "$GITHUB_OUTPUT"
        env:
          GITHUB_TOKEN: ${{ github.token }}

      - name: Extract Mobile-Expensify PR number from URL
        id: extractMobilePRNumber
        if: ${{ inputs.MOBILE_EXPENSIFY_PULL_REQUEST_URL != '' }}
        run: |
          PR_NUMBER=$(echo '${{ inputs.MOBILE_EXPENSIFY_PULL_REQUEST_URL }}' | sed -E 's|.*/pull/([0-9]+).*|\1|')
          if ! [[ "$PR_NUMBER" =~ ^[0-9]+$ ]]; then
            echo "::error::❌ Could not extract PR number from the Mobile-Expensify PR URL. Please provide a valid GitHub PR URL (e.g., https://github.com/Expensify/Mobile-Expensify/pull/12345)"
            exit 1
          fi
          echo "PR_NUMBER=$PR_NUMBER" >> "$GITHUB_OUTPUT"

      - name: Resolve which Mobile-Expensify PR to use
        id: mobileExpensifyPR
        # v8
        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd
        with:
          github-token: ${{ github.token }}
          result-encoding: string
          script: |
            // An explicit Mobile-Expensify PR URL takes precedence over the App PR description
            if ('${{ steps.extractMobilePRNumber.outputs.PR_NUMBER }}') {
              core.setOutput('SOURCE', 'url');
              return '${{ steps.extractMobilePRNumber.outputs.PR_NUMBER }}';
            }

            // Building against Mobile-Expensify main was requested explicitly, so it takes precedence over the App PR description
            if (${{ inputs.MOBILE_EXPENSIFY_MAIN }}) {
              return '';
            }

            if (!'${{ steps.extractAppPRNumber.outputs.PR_NUMBER }}') {
              return '';
            }

            const pullRequest = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: '${{ steps.extractAppPRNumber.outputs.PR_NUMBER }}',
            });

            const body = pullRequest.data.body ?? '';
            const regex = /MOBILE-EXPENSIFY:\s*https:\/\/github.com\/Expensify\/Mobile-Expensify\/pull\/(?<prNumber>\d+)/;
            const found = body.match(regex)?.groups?.prNumber || "";

            core.setOutput('SOURCE', 'description');
            return found.trim();

      - name: Resolve Mobile-Expensify head ref from PR number
        id: getHeadRef
        if: ${{ steps.mobileExpensifyPR.outputs.result != '' }}
        run: |
          set -e
          PR_INFO=$(gh pr view "$PR_NUMBER" -R Expensify/Mobile-Expensify --json state,headRefOid --jq '"\(.state) \(.headRefOid)"')
          read -r STATE REF <<< "$PR_INFO"

          # A merged PR's head commit is stale compared to main, and the pinned submodule of the App PR branch may predate the merge, so build against main, which contains the change
          if [[ "$SOURCE" == 'description' && "$STATE" == 'MERGED' ]]; then
            echo "::notice::Mobile-Expensify PR #$PR_NUMBER from the App PR description is already merged, so Mobile-Expensify main is used instead."
            echo "REF=main" >> "$GITHUB_OUTPUT"
            exit 0
          fi

          echo "PR=$PR_NUMBER" >> "$GITHUB_OUTPUT"
          echo "REF=$REF" >> "$GITHUB_OUTPUT"
        env:
          PR_NUMBER: ${{ steps.mobileExpensifyPR.outputs.result }}
          SOURCE: ${{ steps.mobileExpensifyPR.outputs.SOURCE }}
          GITHUB_TOKEN: ${{ secrets.OS_BOTIFY_TOKEN }}