return getDelegate().getProjectDirectory();
    }

    /**
     * @return the model id as {@code groupId:artifactId:packaging:version}
     */
    public String getId() {
        StringBuilder id = new StringBuilder( 64 );

        id.append( ( getGroupId() == null ) ? "[inherited]" : getGroupId() );
        id.append( ":" );
        id.append( getArtifactId() );
        id.append( ":" );

                doneSignal.countDown();
              }
            });
    thread.start();

    boolean done = doneSignal.await(1, TimeUnit.SECONDS);
    if (!done) {
      StringBuilder builder = new StringBuilder();
      for (StackTraceElement trace : thread.getStackTrace()) {
        builder.append("\tat ").append(trace).append('\n');
      }
      fail(builder.toString());
    }
  }

                doneSignal.countDown();
              }
            });
    thread.start();

    boolean done = doneSignal.await(1, TimeUnit.SECONDS);
    if (!done) {
      StringBuilder builder = new StringBuilder();
      for (StackTraceElement trace : thread.getStackTrace()) {
        builder.append("\tat ").append(trace).append('\n');
      }
      fail(builder.toString());
    }
  }

    }

    @Override
    public String toString() {
      if (areEqual()) {
        return "equal";
      }

      StringBuilder result = new StringBuilder("not equal");
      if (!onlyOnLeft.isEmpty()) {
        result.append(": only on left=").append(onlyOnLeft);
      }
      if (!onlyOnRight.isEmpty()) {