I try the following (in Pseudocode):
tester = new WicketTester();
tester.assertModelValue("test","hello"); --> throws
java.lang.IllegalArgumentException: Component is not a container and so does not contain the path test.
Funny as it is, to make this work, you have to do the following assertion:
The error lies in
public Component getComponentFromLastRenderedPage(String path,
final boolean wantVisibleInHierarchy)
in Line: path = startComponent.getId() + ":" + path;
I will provide a patch this evening.