return Part(headers, body)
      }

      @JvmStatic
      fun createFormData(
        name: String,
        value: String,
      ): Part = createFormData(name, null, value.toRequestBody())

      @JvmStatic
      fun createFormData(
        name: String,
        filename: String?,
        body: RequestBody,
      ): Part {

        # possibly modified.
        #
        # NB: a `for` loop captures its iteration list before it begins, so
        # changing the positional parameters here affects neither the number of
        # iterations, nor the values presented in `arg`.
        shift                   # remove old arg
        set -- "$@" "$arg"      # push replacement arg
    done
fi

    API. Requests made with OkUrlFactory will continue to have a default user
    agent.
 *  New: Guava-like API to create headers:

    ```java
    Headers headers = Headers.of(name1, value1, name2, value2, ...).
    ```

 *  New: Make the content-type header optional for request bodies.
 *  New: `Response.isSuccessful()` is a convenient API to check response codes.

    val instant: Instant? = headers.getInstant("")
    val size: Int = headers.size
    val name: String = headers.name(0)
    val value: String = headers.value(0)
    val names: Set<String> = headers.names()
    val values: List<String> = headers.values("")
    val byteCount: Long = headers.byteCount()
    val builder: Headers.Builder = headers.newBuilder()

 *    default to their previous value.
 *
 * Every [edit] call must be matched by a call to [Editor.commit] or [Editor.abort]. Committing is
 * atomic: a read observes the full set of values as they were before or after the commit, but never
 * a mix of values.
 *
 * Clients call [get] to read a snapshot of an entry. The read will observe the value at the time

  fun assertRequestMethod(method: String) =
    apply {
      assertThat(request.method).isEqualTo(method)
    }

  fun assertRequestHeader(
    name: String,
    vararg values: String,
  ) = apply {
    assertThat(request.headers(name)).containsExactly(*values)
  }

  fun assertCode(expectedCode: Int) =
    apply {
      assertThat(response!!.code).isEqualTo(expectedCode)
    }

  fun assertSuccessful() =
    apply {

 * The range goes until the beginning of the next range.
 *
 * When b2 and b3 are unused, their values are set to 0x2d ('-').
 *
 * Section Index (1,240 bytes)
 * ===========================
 *
 * Each entry is 4 bytes, and represents all the code points that share a 14-bit prefix. Entries are
 * sorted by this 14-bit prefix.
 *
 * We define these values:
 *
 *  * **b0b1s7**: (b0 << 14) + (b1 << 7)
 *  * **b2b3s2**: (b2 << 9) + (b3 << 2)

  COMPRESSION_ERROR(9),

  CONNECT_ERROR(0xa),

  ENHANCE_YOUR_CALM(0xb),

  INADEQUATE_SECURITY(0xc),

  HTTP_1_1_REQUIRED(0xd),
  ;

  companion object {
    fun fromHttp2(code: Int): ErrorCode? = values().find { it.httpCode == code }
  }

  /**
   * Returns an early guess of the next response, used for policy on how an incoming request should
   * be received. The default implementation returns an empty response. Mischievous implementations
   * can return other values to test HTTP edge cases, such as unhappy socket policies or throttled
   * request bodies.
   */
  open fun peek(): MockResponse {
    return MockResponse(socketPolicy = KeepOpen)
  }

  /**

  /** Identifies which member in the ASN.1 schema the field holds. */
  var tag: Long,
  /**
   * If the constructed bit is set it indicates that the value is composed of other values that have
   * their own headers.
   *
   * This value is encoded in bit 6 of the first byte of each value.
   *
   * ```
   * 0bxx0xxxxx Primitive
   * 0bxx1xxxxx Constructed
   * ```
   */
  var constructed: Boolean,