assertThrows(
        IllegalArgumentException.class,
        () -> Traverser.forGraph(createDirectedGraph()).breadthFirst('a'));
  }

  /**
   * Checks that the elements of the iterable are calculated on the fly. Concretely, that means that
   * {@link SuccessorsFunction#successors(Object)} can only be called for a subset of all nodes.
   */
  @Test
  public void forGraph_breadthFirstIterable_emptyGraph() {

}

// getConstant checks that addr represents a plain constant and returns its value.
func (p *Parser) getConstant(prog *obj.Prog, op obj.As, addr *obj.Addr) int64 {
	if addr.Type != obj.TYPE_MEM || addr.Name != 0 || addr.Reg != 0 || addr.Index != 0 {
		p.errorf("%s: expected integer constant; found %s", op, obj.Dconv(prog, addr))
	}
	return addr.Offset
}

    assertThrows(
        IllegalArgumentException.class,
        () -> Traverser.forGraph(createDirectedGraph()).breadthFirst('a'));
  }

  /**
   * Checks that the elements of the iterable are calculated on the fly. Concretely, that means that
   * {@link SuccessorsFunction#successors(Object)} can only be called for a subset of all nodes.
   */
  @Test
  public void forGraph_breadthFirstIterable_emptyGraph() {

		// https://en.wikipedia.org/wiki/Copy_protection so the incoming stream
		// is always going to be in-memory as we cannot re-read from what we
		// wrote to disk - since that amounts to "copying" from a "copy"
		// instead of "copying" from source, we need the stream to be seekable
		// to ensure that we can make fan-out calls concurrently.
		buf := bytebufferpool.Get()
		defer func() {
			buf.Reset()
			bytebufferpool.Put(buf)

        assertNotNull(exception);
        assertEquals(middleCause, exception.getCause());
        assertEquals(rootCause, exception.getCause().getCause());
    }

    public void test_inheritance() {
        // Test that JobProcessingException is a FessSystemException
        final JobProcessingException exception = new JobProcessingException("Test");

        assertTrue(exception instanceof FessSystemException);

  public void testEqualsIgnoreCaseUnicodeEquivalence() {
    // Note that it's possible in future that the JDK's idea to toUpperCase() or equalsIgnoreCase()
    // may change and break assumptions in this test [*]. This is not a bug in the implementation of
    // Ascii.equalsIgnoreCase(), but it is a signal that its documentation may need updating as
    // regards edge cases.

  public void testEqualsIgnoreCaseUnicodeEquivalence() {
    // Note that it's possible in future that the JDK's idea to toUpperCase() or equalsIgnoreCase()
    // may change and break assumptions in this test [*]. This is not a bug in the implementation of
    // Ascii.equalsIgnoreCase(), but it is a signal that its documentation may need updating as
    // regards edge cases.

      public void perform(List<Integer> list) {}
    };
  }

  /** A list that mutates itself after every call to each of its {@link List} methods. */
  interface ConcurrentlyMutatedList<E> extends List<E> {
    /**
     * The elements of a {@link ConcurrentlyMutatedList} are added and removed over time. This
     * method returns every state that the list has passed through at some point.
     */
    Set<List<E>> getAllStates();

    /* It is a little awkward but prudent to pass the quering address
     * so that it may be included in the list of results. IOW we do
     * not want to create a new NbtAddress object for this particular
     * address from which the query is constructed, we want to populate
     * the data of the existing address that should be one of several
     * returned by the node status.
     */

### Transition Status