}

  private void expectReturnsTrue(Target target) {
    String message = Platform.format("retainAll(%s) should return true", target);
    assertTrue(message, collection.retainAll(target.toRetain));
  }

  private void expectReturnsFalse(Target target) {
    String message = Platform.format("retainAll(%s) should return false", target);
    assertFalse(message, collection.retainAll(target.toRetain));
  }

          fail("Expected DecodingException");
        } catch (DecodingException expected) {
          // Don't assert on the expectedMessage; the messages for exceptions thrown from the
          // decoding stream may differ from the messages for the decode methods.
        } catch (IOException e) {
          fail("Expected DecodingException but got: " + e);
        }
      }
    },
    CAN_DECODE {

        List<E> resultsForStrategy = new ArrayList<>();
        strategy.forEach(spliteratorSupplier.get(), resultsForStrategy::add);

        // TODO(cpovirk): better failure messages
        if ((characteristics & Spliterator.NONNULL) != 0) {
          assertFalse(resultsForStrategy.contains(null));
        }
        if ((characteristics & Spliterator.SORTED) != 0) {

  static final Integer NODE_NOT_IN_GRAPH = 1000;

  // TODO(user): Consider separating Strings that we've defined here to capture
  // identifiable substrings of expected error messages, from Strings that we've defined
  // here to provide error messages.
  // TODO(user): Some Strings used in the subclasses can be added as static Strings
  // here too.
  static final String ERROR_MODIFIABLE_SET = "Set returned is unexpectedly modifiable";

          fail("Expected DecodingException");
        } catch (DecodingException expected) {
          // Don't assert on the expectedMessage; the messages for exceptions thrown from the
          // decoding stream may differ from the messages for the decode methods.
        } catch (IOException e) {
          fail("Expected DecodingException but got: " + e);
        }
      }
    },
    CAN_DECODE {

  }

  private void expectReturnsTrue(Target target) {
    String message = Platform.format("retainAll(%s) should return true", target);
    assertTrue(message, collection.retainAll(target.toRetain));
  }

  private void expectReturnsFalse(Target target) {
    String message = Platform.format("retainAll(%s) should return false", target);
    assertFalse(message, collection.retainAll(target.toRetain));
  }

  private static final String E44 = "4-4";
  private static final int NODE_COUNT = 20;
  private static final int EDGE_COUNT = 20;
  // TODO(user): Consider adding both error messages from here and {@link AbstractNetworkTest}
  // in one class (may be a utility class for error messages).
  private static final String ERROR_PARALLEL_EDGE = "connected by a different edge";
  private static final String ERROR_NEGATIVE_COUNT = "is non-negative";

      return conflictingStackTrace;
    }

    /**
     * Appends the chain of messages from the {@code conflictingStackTrace} to the original {@code
     * message}.
     */
    @Override
    public String getMessage() {
      // requireNonNull is safe because ExampleStackTrace sets a non-null message.
      StringBuilder message = new StringBuilder(requireNonNull(super.getMessage()));

 *
 * @param <K> the type of keys used by the maps under test
 * @param <V> the type of mapped values used the maps under test
 * @author George van den Driessche
 */
// TODO: Descriptive assertion messages, with hints as to probable fixes.
// TODO: Add another constructor parameter indicating whether the class under test is ordered, and
// check the order if so.
// TODO: Refactor to share code with SetTestBuilder etc.

  static final String EDGE_NOT_IN_GRAPH = "edgeNotInGraph";

  // TODO(user): Consider separating Strings that we've defined here to capture
  // identifiable substrings of expected error messages, from Strings that we've defined
  // here to provide error messages.
  // TODO(user): Some Strings used in the subclasses can be added as static Strings
  // here too.
  static final String ERROR_PARALLEL_EDGE = "connected by a different edge";