Weird issue with inner class not being covered via Test Class?

Question

I have a test class that is basically covering a class which has structure like

  public class classA {
    public class classB implements Triggers.Handler {
       public void handle(){
         ---some code----
    }
  }
  }

I have a trigger on object, something like

 trigger someTrigger on someObject(before insert, before update) {

new Triggers()

    .bind(Triggers.Evt.beforeInsert, new classA.classB())        

    .manage();
 }

I am inserting someObject in the test class and I also see its going into the ClassB in debug logs, but the code coverage for classA is showing as 0%. I have no idea what the issue is. Any thoughts or help??

Answer 1

There is a known issue http://success.salesforce.com/issues_view?id=a1p30000000Rle5AAC that was apparently fixed in Summer '12 but looks like there was a regression.

I ran into this problem before and was able to workaround it by creating an instance of the Outer class in the test.

@isTest
private class TestClassA {
  static {
    // This should get code coverage on inner class
    new ClassA();
  }

  @isTest static void testSomethingInClassB() {
    ClassA.ClassB b = new ClassA.ClassB();
    b.handle();
  }
}