title: go test: only run tests that contain a build tag?
body: <p>I have a set of long running tests, defined with the build tag. For example, </p>
  
  <pre><code>// file some_test.go
  //+build func_test
  
  (rest of file with test cases)
  </code></pre>
  
  <p>And I have many other shorter running tests, without this build flag.
  Is there a way I can easily run only the tests containing the build tag "func_test"?</p>
  
  <p>Note that if I just run <code>go test -tags func_test</code>, it runs ALL tests including the ones in <code>some_test.go</code>.</p>