Writing Unit Tests

Recommended resources

• JUnit homepage
• JUnit Cookbook (Eric Gamma, Kent Beck)
• JUnit: A Cook's Tour (Eric Gamma, Kent Beck)
• JUnitTest Infected: Programmers Love Writing Tests

• Put your test classes in src/test.

• Add the ant task that executes your test to src/targets/test-build.xml.

Most tests will need a publication in the install (servlet container) directory. To provide a predictable test publication, the clean default publication from the build directory is copied to the test publication in the installation directory.

In the test buildfile, the test publication is setup by the test.pub.prepare target. The directory {{${install.dir}/lenya/pubs/test}} is deleted (so that the files created by former tests are removed), and the default publication is copied to this directory. Add this target to the depends attribute of your test target if you need the test publication.

To simplify the acces to a publication you can use the class org.apache.lenya.cms.PublicationHelper. It provides the following methods:

    /**
     * Initializes the object with the first parameters from the command
     * line arguments <code>args</code>. The remainder of the array is returned.
     * @param args The command line arguments of the test.
     * @return The remainder of the arguments after the publication
     * parameters are extracted.
     */
    public static String[] extractPublicationArguments(String args[]);

    /**
     * Returns the publication.
     * @return A publication object.
     */
    public static Publication getPublication();

The extractPublicationArguments(String[]) method extracts the first two strings from the args parameter. The first one is the servlet context path, the second is the publication ID.

To make use of the PublicationHelper, you have to call the extractPublicationArguments(String[]) method in the main(String()) method of your TestCase class. This initializes the PublicationHelper:

    public static void main(String[] args) {

        // extract the arguments needed for setting up the publication
        // only the remaining arguments are returned
        args = PublicationHelper.extractPublicationArguments(args);

        ...
    }

public class MyTest extends TestCase {

    // static fields to store test parameters
    private File configFile;
    ...
    
    /** Constructor. */
    public MyTest(String test) {
        super(test);
    }

    /**
     * The main program.
     * The parameters are set from the command line arguments.
     *
     * @param args The command line arguments.
     */
    public static void main(String[] args) {
        args = PublicationHelper.extractPublicationArguments(args);
        setConfigFile(args[0]);
        TestRunner.run(getSuite());
    }

    /** Returns the test suite. */
    public static Test getSuite() {
        return new TestSuite(MyTest.class);
    }

    /** Tests whatever you want. */
    public void testSomething() {
        ...
    }

    /** Sets a parameter value. */
    protected static void setConfigFile(String fileName) {
        assertNotNull(string);
        File publicationDirectory
            = PublicationHelper.getPublication().getDirectory();
        configFile = new File(publicationDirectory, fileName);
        assertTrue(configFile.exists());
    }

    /** Returns a parameter value. */
    protected static File getConfigFile() {
        return configFile;
    }
}

For debugging, it might be desired to run the test from an API. In this case, the main(String[]) method is never executed.

To provide the parameters, you can hardcode them as fallback in the TestCase.setup() method that is called before the test is invoked:

    /** @see junit.framework.TestCase#setUp() */
    protected void setUp() throws Exception {
        if (getConfigFile() == null) {
            String args[] = {
                "D:\\Development\\build\\tomcat-4.1.24\\webapps\\lenya",
                "test"
            };
            PublicationHelper.extractPublicationArguments(args);
            setConfigFile("config/something.xconf");
        }
    }

The test buildfile is located at src/targets/test-build.xml. It contains the following common targets:

• test - Runs all tests.

• tests.junit - Runs the JUnit tests.

• tests.anteater - Runs the Anteater tests.

• tests.prepare - Prepares the tests, e.g. compiles test classes.

• test.pub.prepare - Prepares the test publication.

To add your test to the buildfile, you create a target called test.<name>.

If you use assertions (Java assertions, not the JUnit ones) in your test, it is important to enable them using the -ea or -enableassertions argument.

  <target name="test.my" depends="test.pub.prepare">
    <!-- My Test -->
    <java fork="yes" classname="org.apache.lenya.cms.mypackage.MyTest">
      <jvmarg value="-enableassertions"/>

      <arg value="${install.dir}"/>           // PublicationHelper
      <arg value="test"/>                     // PublicationHelper
      <arg value="config/something.xconf"/>   // MyTest

      <classpath refid="classpath"/>

      <classpath>
        <pathelement location="${build.test}" />
        <pathelement path="${build.root}/lenya/webapp/WEB-INF/classes" />
        <fileset dir="${build.root}/lenya/webapp/WEB-INF/lib">
          <include name="ant**.jar"/>
        </fileset>

      </classpath>
    </java>
  </target>

Finally, you have to add the test to the tests.junit target:

<target name="tests.junit" depends="init, tests.prepare, ..., test.my">

Now you can run the tests:

$LENYA_HOME > build test

If you want to call your test independently, you have to call the preparation targets before:

$LENYA_HOME > build init
$LENYA_HOME > build tests.prepare
$LENYA_HOME > build test.my