* 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
   * characters unescaped, they would be escaped by the consumer at parse time, anyway.</a>)
   * Additionally, the escaper escapes the slash character ("/"). While slashes are acceptable in

private fun Buffer.startsWith(prefix: Byte): Boolean = !exhausted() && this[0] == prefix

/**
 * Reads a double-quoted string, unescaping quoted pairs like `\"` to the 2nd character in each
 * sequence. Returns the unescaped string, or null if the buffer isn't prefixed with a
 * double-quoted string.
 */
@Throws(EOFException::class)
private fun Buffer.readQuotedString(): String? {
  require(readByte() == '\"'.code.toByte())

    try {
      e.escape((String) null);
      fail("Escaping null string should throw exception");
    } catch (NullPointerException x) {
      // pass
    }

    // All URL escapers should leave 0-9, A-Z, a-z unescaped
    assertUnescaped(e, 'a');
    assertUnescaped(e, 'z');
    assertUnescaped(e, 'A');
    assertUnescaped(e, 'Z');
    assertUnescaped(e, '0');
    assertUnescaped(e, '9');

   * 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
   * characters unescaped, they would be escaped by the consumer at parse time, anyway.</a>)
   * Additionally, the escaper escapes the slash character ("/"). While slashes are acceptable in

 * code point. An additional safe range is provided that determines whether code points without
 * specific replacements are to be considered safe and left unescaped or should be escaped in a
 * general way.
 *
 * <p>A good example of usage of this class is for HTML escaping where the replacement array
 * contains information about the named HTML entities such as {@code &amp;} and {@code &quot;} while

    try {
      e.escape((String) null);
      fail("Escaping null string should throw exception");
    } catch (NullPointerException x) {
      // pass
    }

    // All URL escapers should leave 0-9, A-Z, a-z unescaped
    assertUnescaped(e, 'a');
    assertUnescaped(e, 'z');
    assertUnescaped(e, 'A');
    assertUnescaped(e, 'Z');
    assertUnescaped(e, '0');
    assertUnescaped(e, '9');

    assertEquals("string with spaces", spaceEscaper.escape("string with spaces"));
  }

  /** Tests that if we add extra 'safe' characters they remain unescaped */
  public void testCustomEscaper() {
    UnicodeEscaper e = new PercentEscaper("+*/-", false);
    for (char c = 0; c < 128; c++) {
      if ((c >= '0' && c <= '9')
          || (c >= 'a' && c <= 'z')

    assertEquals("string with spaces", spaceEscaper.escape("string with spaces"));
  }

  /** Tests that if we add extra 'safe' characters they remain unescaped */
  public void testCustomEscaper() {
    UnicodeEscaper e = new PercentEscaper("+*/-", false);
    for (char c = 0; c < 128; c++) {
      if ((c >= '0' && c <= '9')
          || (c >= 'a' && c <= 'z')

 * {@code char} value. An additional safe range is provided that determines whether {@code char}
 * values without specific replacements are to be considered safe and left unescaped or should be
 * escaped in a general way.
 *
 * <p>A good example of usage of this class is for Java source code escaping where the replacement
 * array contains information about special ASCII characters such as {@code \\t} and {@code \\n}

      }
      return
    }

    // If the URI has more escaping than the HttpURL, check that the decoded values still match.
    val uriEscaped = uriEscapedCodePoints.indexOf(codePointString) != -1
    if (uriEscaped) {
      if (uri.toString() == httpUrl.toString()) {
        fail("Encoding $component $codePoint using $encoding")
      }
      if (component[toAndFromUri!!] != codePointString) {