/**
 * @author David Beaumont
 */
@GwtCompatible
@NullUnmarked
public class EscapersTest extends TestCase {
  public void testNullEscaper() throws IOException {
    Escaper escaper = Escapers.nullEscaper();
    EscaperAsserts.assertBasic(escaper);
    String s = "\0\n\t\\az09~\uD800\uDC00\uFFFF";
    assertWithMessage("null escaper should have no effect").that(escaper.escape(s)).isEqualTo(s);
  }

 * your own escapers, use {@link CharEscaperBuilder}, or extend {@code CharEscaper} or {@code
 * UnicodeEscaper}.
 *
 * @author David Beaumont
 * @since 15.0
 */
@DoNotMock("Use Escapers.nullEscaper() or another methods from the *Escapers classes")
@GwtCompatible
@SuppressWarnings("EscapedEntity") // We do mean for the user to see "<" etc.
public abstract class Escaper {

   */
  public static Escaper nullEscaper() {
    return NULL_ESCAPER;
  }

  // An Escaper that efficiently performs no escaping.
  // Extending CharEscaper (instead of Escaper) makes Escapers.compose() easier.
  private static final Escaper NULL_ESCAPER =
      new CharEscaper() {
        @Override
        public String escape(String string) {