svoid test_getTypeArgumentAsClass() {
  class X {
    LS bla;
    L x;
  }
  
  Type type = genericFieldType(X.class, 'bla);
  assertEqualsVerbose(S.class, getTypeArgumentAsClass(type));
  assertEqualsVerbose(null, getTypeArgumentAsClass(genericFieldType(X.class, 'x)));
}