Using @RunWith(Enclosed.class) to nest tests
This makes it easier to identify and isolate the tests for each method from the others.
It works as long as the nested classes are static classes.  Using @RunWith(Enclosed.class) checks for this, but also seems to have the side effect of showing a doubled ignored test for each pass/fail test.
Removing @RunWith(Enclosed.class) still runs the tests as a whole suite, but only allows you to run one nested class at a time in Eclipse.
For further nesting levels, the Enclosed test runner seems to miss some tests when running in Eclipse.
HierarchicalContextRunner works better for mixed nesting levels.
Sterring clear of empty test classes, which produce odd atomic-test behavior in Description.
Test for getChildren / run