title: How to set per-sub-project properties from a Gradle command line?
body: <p>I have the following:</p>
  
  <pre><code>// File: build.gradle
  subprojects {
      test {
          final testRatioOfWaitTimeToComputeTime = System.getProperty('test.ratio-of-wait-time-to-compute-time', '1') as int
          final testMaxParallelForks = (System.getProperty('test.max-parallel-forks') as Integer) ?: numberOfForks(testRatioOfWaitTimeToComputeTime)
  
          maxParallelForks testMaxParallelForks
      }
  }
  </code></pre>
  
  <p>How would I:</p>
  
  <ul>
  <li>Specify a default for <code>test.ratio-of-wait-time-to-compute-time</code> and <code>test.max-parallel-forks</code> for <strong>one</strong> specific sub-project?</li>
  <li>Specify a command-line override for <code>test.ratio-of-wait-time-to-compute-time</code> and <code>test.max-parallel-forks</code> for <strong>one</strong> specific sub-project?</li>
  </ul>
  
  <p>I've tried various combinations of <code>-P</code> and <code>-D</code> with both with and without prefixing the property with the sub-project name (eg <code>:sub-project:test.ratio-of-wait-time-to-compute-time</code>).</p>