}
        };
    EscaperAsserts.assertBasic(escaper);
    assertThat(escaper.escape("\tFish & Chips\n")).isEqualTo("<tab>Fish <and> Chips<newline>");

    // Verify that everything else is left unescaped.
    String safeChars = "\0\u0100\uD800\uDC00\uFFFF";
    assertThat(escaper.escape(safeChars)).isEqualTo(safeChars);

    // Ensure that Unicode escapers behave correctly wrt badly formed input.

  public static Escaper xmlAttributeEscaper() {
    return XML_ATTRIBUTE_ESCAPER;
  }
  private static final Escaper XML_CONTENT_ESCAPER;
  private static final Escaper XML_ATTRIBUTE_ESCAPER;

  static {
    Escapers.Builder builder = Escapers.builder();
    // The char values \uFFFE and \uFFFF are explicitly not allowed in XML

    Escaper escaper = Escapers.builder().setSafeRange('a', 'z').build();
    assertThat(escaper.escape("The Quick Brown Fox")).isEqualTo("The Quick Brown Fox");
  }

  public void testBuilderInitialStateNoneUnsafe() {
    // No characters are unsafe by default (safeMin == 0, safeMax == 0xFFFF).
    Escaper escaper = Escapers.builder().setUnsafeReplacement("X").build();
    assertThat(escaper.escape("\0\uFFFF")).isEqualTo("\0\uFFFF");

 * As such sharing this data structure between escaper instances is the primary goal of this class.
 *
 * @author David Beaumont
 * @since 15.0
 */
@GwtCompatible
public final class ArrayBasedEscaperMap {
  /**
   * Returns a new ArrayBasedEscaperMap for creating ArrayBasedCharEscaper or
   * ArrayBasedUnicodeEscaper instances.
   *
   * @param replacements a map of characters to their escaped representations
   */

 * UTF-8.
 *
 * <p><b>Note:</b> This escaper produces <a
 * href="https://url.spec.whatwg.org/#percent-encode">uppercase</a> hexadecimal sequences.
 *
 * @author David Beaumont
 * @since 15.0
 */
@GwtCompatible
public final class PercentEscaper extends UnicodeEscaper {

  // In some escapers spaces are escaped to '+'
  private static final char[] plusSign = {'+'};

  public void testAddEscapes() {
    char[] cs = {'a', 'b', 'c'};
    CharEscaperBuilder builder = new CharEscaperBuilder().addEscapes(cs, "Z");
    Escaper escaper = builder.toEscaper();
    assertThat(escaper.escape("abcdef")).isEqualTo("ZZZdef");
  }

          destIndex += charsSkipped;
        }
        if (escaped.length > 0) {
          System.arraycopy(escaped, 0, dest, destIndex, escaped.length);
          destIndex += escaped.length;
        }
        // If we dealt with an escaped character, reset the unescaped range.
        unescapedChunkStart = nextIndex;
      }
      index = nextEscapeIndex(s, nextIndex, end);
    }

    }
    return result;
  }

  /**
   * Convert this builder into a char escaper which is just a decorator around the underlying array
   * of replacement char[]s.
   *
   * @return an escaper that escapes based on the underlying array.
   */
  public Escaper toEscaper() {
    return new CharArrayDecorator(toArray());
  }

public abstract class CharEscaper extends Escaper {
  /** Constructor for use by subclasses. */
  protected CharEscaper() {}

  /**
   * Returns the escaped form of a given literal string.
   *
   * @param string the literal string to be escaped
   * @return the escaped form of {@code string}
   * @throws NullPointerException if {@code string} is null
   */
  @Override
  public String escape(String string) {

    assertUnicodeEscaping(e, "%F4%8F%BF%BF", '\uDBFF', '\uDFFF');

    // simple string tests
    assertEquals("", e.escape(""));
    assertEquals("safestring", e.escape("safestring"));
    assertEquals("embedded%00null", e.escape("embedded\0null"));
    assertEquals("max%EF%BF%BFchar", e.escape("max\uffffchar"));
  }

  /** Tests the various ways that the space character can be handled */
  public void testPlusForSpace() {