assertThat(stringPrep("\u2029")).isNull()
    assertThat(stringPrep("\ud834\udd7a")).isNull() // Note that this is one code point.
  }

  @Test fun prohibitionPrivateUse() {
    assertThat(stringPrep("\uf8ff")).isNull()
    assertThat(stringPrep("\udbff\udffd")).isNull() // Note that this is one code point.
  }

  @Test fun prohibitionNonCharacter() {
    assertThat(stringPrep("\ufdd0")).isNull()

    ) {
    }
  }

  companion object {
    /** Arbitrary code point that's 2 bytes in UTF-8 and valid in IdnaMappingTable.txt. */
    private const val UNICODE_2 = 0x1a5

    /** Arbitrary code point that's 3 bytes in UTF-8 and valid in IdnaMappingTable.txt. */
    private const val UNICODE_3 = 0x2202

    /** Arbitrary code point that's 4 bytes in UTF-8 and valid in IdnaMappingTable.txt. */

  }

  @Test fun `point with only x set`() {
    val bytes = "3003800109".decodeHex()
    val point = Point(9L, null)
    assertThat(Point.ADAPTER.fromDer(bytes)).isEqualTo(point)
    assertThat(Point.ADAPTER.toDer(point)).isEqualTo(bytes)
  }

  @Test fun `point with only y set`() {
    val bytes = "3003810109".decodeHex()
    val point = Point(null, 9L)

  }

  @Test fun outOfBounds() {
    assertFailsWith<IllegalArgumentException> {
      table.map(-1, Buffer())
    }
    table.map(0, Buffer()) // Lowest legal code point.
    table.map(0x10ffff, Buffer()) // Highest legal code point.
    assertFailsWith<IllegalArgumentException> {
      table.map(0x110000, Buffer())
    }
  }

  @Test fun binarySearchEvenSizedRange() {

 *
 * Code Points in Sections
 * =======================
 *
 * The full range of code points is 0..0x10fffe. We can represent any of these code points with 21
 * bits.
 *
 * We split each code point into a 14-bit prefix and a 7-bit suffix. All code points with the same
 * prefix are called a 'section'. There are 128 code points per section.
 *
 * Ranges Data (32,612 bytes)
 * ==========================
 *

          mappedTo.writeUtf8CodePoint(readHexadecimalUnsignedLong().toInt())
        }
      }

      TYPE_DISALLOWED, TYPE_DISALLOWED_STD3_VALID, TYPE_IGNORED, TYPE_VALID -> Unit

      else -> throw IOException("unexpected type")
    }

    skipRestOfLine()

    result +=
      Mapping(
        sourceCodePoint0.toInt(),
        sourceCodePoint1.toInt(),
        type,
        mappedTo.readByteString(),

    // appendCodePoint(). The Punycode algorithm processes code points in increasing code-point
    // order, not in increasing index order.
    val codePoints = mutableListOf<Int>()

    // consume all code points before the last delimiter (if there is one)
    //  and copy them to output, fail on any non-basic code point
    val lastDelimiter = string.lastIndexOf('-', limit)
    if (lastDelimiter >= pos) {

   * For example, the tags in this schema are 0 and 1:
   *
   * ```
   * Point ::= SEQUENCE {
   *   x [0] INTEGER OPTIONAL,
   *   y [1] INTEGER OPTIONAL
   * }
   * ```
   *
   * You may also specify a tag class like [DerHeader.TAG_CLASS_APPLICATION]. The default tag class
   * is [DerHeader.TAG_CLASS_CONTEXT_SPECIFIC].
   *
   * ```
   * Point ::= SEQUENCE {
   *   x [APPLICATION 0] INTEGER OPTIONAL,

   * operation is required.
   *
   * This is invoked at most once, even if [Call.cancel] is invoked multiple times. It may be
   * invoked at any point in a call's life, including before [callStart] and after [callEnd].
   */
  open fun canceled(call: Call) {
  }

  /**
   * Invoked when a call fails due to cache rules.

 *
 * If your authentication may be flaky and requires retries you should apply some policy
 * to limit the retries by the class of errors and number of attempts.  To get the number of
 * attempts to the current point use this function.
 *
 * ```java
 * private int responseCount(Response response) {
 *   int result = 1;
 *   while ((response = response.priorResponse()) != null) {
 *     result++;
 *   }