Description Moritz Eysholdt 2012-10-03 10:50:36 EDT

Created attachment 221840 [details]
runner_ui_extensionpoint_v01

I'm proposing to contribute an extension point which allows to customize the JUnit View for specific JUnit runner implementations. 

JUnit has this great concept of custom runners which are responsible for executing a set of test cases. This brings a lot of flexibility: The runner can load test data (from files, Java classes, etc.) and decide what a "test case" actually is (A Java method, a text snippet, etc.) and how often a test case should be invoked with which test data. 

However, the current JUnit view has some limitations:
- The test's label in the tree view must begin with the Java method's name
- Navigating to Java methods (double click on the tree item or context menu) only works when the Java method has no parameters.
- Navigation to test data (for example in *.csv files) is not possible.
- Visualization of test failures is restricted to stack traces and the diff dialog. 

The extensions point I'm proposing allows to register a handler class for a specific JUnit runner. This handler class may:
- specify the label of the test (-case/-suite) as shown in the tree view
- add items to the context menu for tree view items
- handle double-clicks on tree view items. 

This is an example for the "Theories" runner form JUnit itself (see also bug 200403):


-------- A JUnit test using theories ----------
@RunWith(Theories.class)
public class TheorieTest {

	@DataPoint
	public static String a = "a";

	@DataPoint
	public static String b = "bb";

	@DataPoint
	public static String c = "ccc";

	@Theory
	public void stringTest(String x, String y) {
		Assert.assertTrue(x.length() >= 1);
		System.out.println(x + " " + y);
	}
}
---------------------------------------------


---------- Example extension ----------------
<extension point="org.eclipse.jdt.junit.runners.junitRunnerUI">
  <junitRunnerUIHandler
    handlerClass="de.itemis.junit.theories.ui.TheoriesRunnerUIHandler"
    runnerClass="org.junit.experimental.theories.Theories">
  </junitRunnerUIHandler>
</extension>
----------------------------------------------


----------- Extension implementation ---------
public class TheoriesRunnerUIHandler implements IRunnerUIHandler {

  @Override
  public boolean contextMenuAboutToShow(ViewPart part, ITestElement element, IMenuManager menu) {
    if (element instanceof TestCaseElement) {
      menu.add(new OpenTestTheoryAction((TestRunnerViewPart) part, (TestCaseElement) element));
      return true;
    }
    return false;
  }

  @Override
  public boolean handleDoubleClick(ViewPart part, ITestElement element) {
    if (element instanceof TestCaseElement) {
      Action action = new OpenTestTheoryAction((TestRunnerViewPart) part, (TestCaseElement) element);
      if (action.isEnabled()) {
        action.run();
        return true;
      }
    }
    return false;
  }

  @Override
  public String getSimpleLabel(ViewPart part, ITestElement element) {
    if (element instanceof ITestCaseElement)
      return ((ITestCaseElement) element).getTestMethodName() + " theory";
    if (element instanceof ITestSuiteElement)
      return ((ITestSuiteElement) element).getSuiteTypeName();
    return "unknown";
  }

}
--------------------------------------------


The current implementation (see attached or at https://github.com/meysholdt/eclipse_jdt_junit_runners) is quite hacky (base on Java reflection). 

I'm posting this to see if an extension point like this is thinkable, to get feedback, and to gather with others interested in this feature.