The Disco Blog

As I’ve mentioned before, JUnit tests written in Groovy (against a Java application) are sometimes easier to write than in plain-Jane Java because of Groovy’s relaxed syntax. And fewer imports, fewer type declarations, and no semi-colons are just the tip of the iceberg too, man.

Running Groovy JUnit tests through an existing build process managed by Ant or Maven is simple too- especially when a project already has existing hip Java JUnit tests. Ideally, in this scenario, the difference between a Java test and a Groovy one should be seamless- having two different tasks that run each platform’s tests seems like overkill- why not run the Groovy ones with the Java ones?

Groovy bundles a TestSuite type dubbed AllTestSuite, which facilitates running Groovy JUnit scripts from within an IDE and of course, a build process that already runs normal Java JUnit tests. The copasetic class works by looking for System properties which delineate where Groovy tests reside and a naming pattern (such as tests/groovy and **/*Test.groovy).

What I find most effective; however, is to create my own dynomite TestSuite type, set the System properties in a static block and then override the suite method and call AllTestSuite’s suite like so:

package test.com.acme.sda;

import groovy.util.AllTestSuite;
import junit.framework.Test;
import junit.framework.TestSuite;

public class AllGroovySuite extends TestSuite {	

 static {
  System.setProperty(AllTestSuite.SYSPROP_TEST_DIR, "./test/groovy");
  System.setProperty(AllTestSuite.SYSPROP_TEST_PATTERN, "**/*Test.groovy");
 }

 public static void main(String[] args) {
  junit.textui.TestRunner.run(AllTestSuite.suite());
 }	

 public static Test suite() {
  return AllTestSuite.suite();
 }
}

Note how AllGroovySuite is written in normal Java and provides values for Groovy’s AllTestSuite‘s SYSPROP_TEST_DIR and SYSPROP_TEST_PATTERN. When this class is run via a JUnit runner, the SYSPROP_TEST_DIR directory is scanned and any file matching the SYSPROP_TEST_PATTERN pattern is loaded by AllTestSuite and run.

By adopting this technique, I can run Groovy test scripts in an IDE, like Eclipse (and of course, see the green bar); furthermore, existing test tasks in Ant or goals in Maven can pick this class up and run it (which then runs all Groovy tests). Pretty groovy, eh?