/**
 * Static utility methods pertaining to {@link Escaper} instances.
 *
 * @author Sven Mawson
 * @author David Beaumont
 * @since 15.0
 */
@GwtCompatible
public final class Escapers {
  private Escapers() {}

  /**
   * Returns an {@link Escaper} that does no escaping, passing all character data through unchanged.
   */
  public static Escaper nullEscaper() {
    return NULL_ESCAPER;
  }

  /**
   * Returns an {@link Escaper} instance that escapes strings so they can be safely included in <a
   * href="https://url.spec.whatwg.org/#syntax-url-path-segment">URL path segments</a>. The returned
   * escaper escapes all non-ASCII characters, even though <a
   * href="https://url.spec.whatwg.org/#url-code-points">many of these are accepted in modern
   * URLs</a>. (<a href="https://url.spec.whatwg.org/#path-state">If the escaper were to leave these

   */
  public static Escaper xmlContentEscaper() {
    return XML_CONTENT_ESCAPER;
  }

  /**
   * Returns an {@link Escaper} instance that escapes special characters in a string so it can
   * safely be included in XML document as an attribute value. See section <a
   * href="http://www.w3.org/TR/2008/REC-xml-20081126/#AVNormalize">3.3.3</a> of the XML
   * specification.
   *

    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();

  /**
   * Returns an {@link Escaper} instance that escapes strings so they can be safely included in <a
   * href="https://url.spec.whatwg.org/#syntax-url-path-segment">URL path segments</a>. The returned
   * escaper escapes all non-ASCII characters, even though <a
   * href="https://url.spec.whatwg.org/#url-code-points">many of these are accepted in modern
   * URLs</a>. (<a href="https://url.spec.whatwg.org/#path-state">If the escaper were to leave these

@GwtCompatible
@NullUnmarked
final class UrlEscaperTesting {
  /**
   * Helper to assert common expected behaviour of uri escapers. You should call
   * assertBasicUrlEscaper() unless the escaper explicitly does not escape '%'.
   */
  static void assertBasicUrlEscaperExceptPercent(UnicodeEscaper e) {
    // URL escapers should throw null pointer exceptions for null input
    try {
      e.escape((String) null);

 * 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 {

/**
 * A {@code UnicodeEscaper} that escapes some set of Java characters using a UTF-8 based percent
 * encoding scheme. The set of safe characters (those which remain unescaped) can be specified on
 * construction.
 *
 * <p>This class is primarily used for creating URI escapers in {@link UrlEscapers} but can be used
 * directly if required. While URI escapers impose specific semantics on which characters are

  private EscaperAsserts() {}

  /**
   * Asserts that an escaper behaves correctly with respect to null inputs.
   *
   * @param escaper the non-null escaper to test
   */
  public static void assertBasic(Escaper escaper) throws IOException {
    // Escapers operate on characters: no characters, no escaping.
    Assert.assertEquals("", escaper.escape(""));
    // Assert that escapers throw null pointer exceptions.
    try {

  private EscaperAsserts() {}

  /**
   * Asserts that an escaper behaves correctly with respect to null inputs.
   *
   * @param escaper the non-null escaper to test
   */
  public static void assertBasic(Escaper escaper) throws IOException {
    // Escapers operate on characters: no characters, no escaping.
    Assert.assertEquals("", escaper.escape(""));
    // Assert that escapers throw null pointer exceptions.
    try {