.github/actions/setup-bun/action.yml

name: "Setup Bun"
description: "Setup Bun with caching and install dependencies"
inputs:
  install-flags:
    description: "Additional flags to pass to 'bun install'"
    required: false
    default: ""
runs:
  using: "composite"
  steps:
    # node-gyp@latest (invoked via bunx for native install scripts) requires Node >=22;
    # some runner images ship an older system Node on PATH
    - name: Setup Node
      uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
      with:
        node-version: "24"

    - name: Get baseline download URL
      id: bun-url
      shell: bash
      run: |
        if [ "$RUNNER_ARCH" = "X64" ]; then
          V=$(node -p "require('./package.json').packageManager.split('@')[1]")
          case "$RUNNER_OS" in
            macOS)   OS=darwin ;;
            Linux)   OS=linux ;;
            Windows) OS=windows ;;
          esac
          echo "url=https://github.com/oven-sh/bun/releases/download/bun-v${V}/bun-${OS}-x64-baseline.zip" >> "$GITHUB_OUTPUT"
        fi

    - name: Setup Bun
      uses: oven-sh/setup-bun@0c5077e51419868618aeaa5fe8019c62421857d6 # v2.2.0
      with:
        bun-version-file: ${{ !steps.bun-url.outputs.url && 'package.json' || '' }}
        bun-download-url: ${{ steps.bun-url.outputs.url }}

    - name: Get cache directory
      id: cache
      shell: bash
      run: echo "dir=$(bun pm cache)" >> "$GITHUB_OUTPUT"

    - name: Restore Bun dependencies
      id: bun-cache
      uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
      with:
        path: ${{ steps.cache.outputs.dir }}
        key: ${{ runner.os }}-bun-${{ hashFiles('**/bun.lock') }}
        restore-keys: |
          ${{ runner.os }}-bun-

    - name: Install setuptools for distutils compatibility
      run: python3 -m pip install setuptools || pip install setuptools || true
      shell: bash

    - name: Install dependencies
      run: |
        # Workaround for patched peer variants
        # e.g. ./patches/ for standard-openapi
        # https://github.com/oven-sh/bun/issues/28147
        if [ "$RUNNER_OS" = "Windows" ]; then
          bun install --linker hoisted ${{ inputs.install-flags }}
        else
          bun install ${{ inputs.install-flags }}
        fi
      shell: bash

    - name: Save Bun dependencies
      if: steps.bun-cache.outputs.cache-hit != 'true' && github.event_name != 'pull_request' && github.event_name != 'pull_request_target'
      uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
      with:
        path: ${{ steps.cache.outputs.dir }}
        key: ${{ runner.os }}-bun-${{ hashFiles('**/bun.lock') }}