name: Dynamic Runner Selection

on:
  pull_request:

jobs:
  build:
    runs-on: >-
      ${{ 
        github.base_ref == 'test1' && 'ubuntu-24.04' ||
        github.base_ref == 'test2' && 'ubuntu-22.04' ||
        github.base_ref == 'test3' && 'ubuntu-20.04' ||
        'ubuntu-latest'
      }}
      
    steps:
    - name: Checkout code
      uses: actions/checkout@v3

    - name: Run a sample command
      run: echo "Running on ${{ runner.os }} ${{ runner.name }}"