new IntegerDiv10(11), "eleven",
            new IntegerDiv10(35), "thirty five",
            new IntegerDiv10(12), "twelve");

    assertThrows(IllegalArgumentException.class, () -> ImmutableSortedMap.copyOf(original));
  }

  public void testImmutableMapCopyOfImmutableSortedMap() {
    IntegerDiv10 three = new IntegerDiv10(3);
    IntegerDiv10 eleven = new IntegerDiv10(11);

    }

    /**
     * Adds {@code element} to the {@code ImmutableList}.
     *
     * @param element the element to add
     * @return this {@code Builder} object
     * @throws NullPointerException if {@code element} is null
     */
    @CanIgnoreReturnValue
    @Override
    public Builder<E> add(E element) {
      super.add(element);
      return this;
    }

    /**

    public void test_getCause_withNestedExceptions() {
        // Test deeply nested exception causes
        Exception level3 = new Exception("Level 3: Database connection failed");
        Exception level2 = new Exception("Level 2: User lookup failed", level3);
        Exception level1 = new Exception("Level 1: Authentication service error", level2);
        SsoProcessException topLevel = new SsoProcessException("SSO process failed", level1);

  }

  /**
   * Returns {@code element} cast to {@code E}, if it actually is a nonnull E. Otherwise, throws
   * either a NullPointerException or a ClassCastException as appropriate.
   */
  private void checkIsE(Object element) {
    checkNotNull(element);
    if (!isActuallyE(element)) {
      throw new ClassCastException("Expected an " + type + " but got " + element);
    }
  }

  @Override

        // Verify that the stack trace contains this test method
        boolean foundTestMethod = false;
        for (StackTraceElement element : exception.getStackTrace()) {
            if (element.getMethodName().equals("test_stackTrace") && element.getClassName().equals(this.getClass().getName())) {
                foundTestMethod = true;
                break;
            }
        }

   *
   * @throws IllegalArgumentException if {@code node} is not an element of this network
   */
  int outDegree(N node);

  /**
   * Returns the nodes which are the endpoints of {@code edge} in this network.
   *
   * @throws IllegalArgumentException if {@code edge} is not an element of this network
   */
  EndpointPair<N> incidentNodes(E edge);

  /**

        Throwable middleCause = new IllegalStateException("Middle cause", rootCause);
        ScheduledJobException exception = new ScheduledJobException("Top level error", middleCause);

        assertEquals("Top level error", exception.getMessage());
        assertEquals(middleCause, exception.getCause());
        assertEquals("Middle cause", exception.getCause().getMessage());

    MinMaxPriorityQueue<Element> queue = MinMaxPriorityQueue.create();
    int range = Element.values().length;
    for (int iter = 0; iter < reduceIterationsIfGwt(1000); iter++) {
      for (int i = 0; i < 100; i++) {
        Element element = Element.values()[random.nextInt(range)];
        elements.add(element);
        queue.add(element);
      }

    }

    /**
     * Adds {@code element} to the {@code ImmutableSortedSet}. If the {@code ImmutableSortedSet}
     * already contains {@code element}, then {@code add} has no effect. (only the previously added
     * element is retained).
     *
     * @param element the element to add
     * @return this {@code Builder} object
     * @throws NullPointerException if {@code element} is null
     */
    @CanIgnoreReturnValue

        assertTrue(exception.getStackTrace().length > 0);

        // Verify the stack trace contains this test method
        boolean foundTestMethod = false;
        for (StackTraceElement element : exception.getStackTrace()) {
            if (element.getMethodName().equals("test_stackTrace")) {
                foundTestMethod = true;
                break;
            }
        }
        assertTrue(foundTestMethod);
    }