@Override
                public boolean apply(Method method) {
                  return method.getName().startsWith("test")
                      && Modifier.isPublic(method.getModifiers())
                      && method.getParameterTypes().length == 0;
                }
Returns a test suite for testing file methods with a variety of {@code HeapDisk}
configurations.
jimfs/src/test/java/com/google/common/jimfs/RegularFileTest.java