070F; SYRIAC ABBREVIATION MARK
   180E; MONGOLIAN VOWEL SEPARATOR
   200C; ZERO WIDTH NON-JOINER
   200D; ZERO WIDTH JOINER
   2028; LINE SEPARATOR
   2029; PARAGRAPH SEPARATOR
   2060; WORD JOINER
   2061; FUNCTION APPLICATION
   2062; INVISIBLE TIMES
   2063; INVISIBLE SEPARATOR
   206A-206F; [CONTROL CHARACTERS]
   FEFF; ZERO WIDTH NO-BREAK SPACE
   FFF9-FFFC; [CONTROL CHARACTERS]

 * Each connection can carry a varying number of streams, depending on the underlying protocol being
 * used. HTTP/1.x connections can carry either zero or one streams. HTTP/2 connections can carry any
 * number of streams, dynamically configured with `SETTINGS_MAX_CONCURRENT_STREAMS`. A connection
 * currently carrying zero streams is an idle stream. We keep it alive because reusing an existing
 * connection is typically faster than establishing a new one.
 *

    // hair space
    assertThat(parse("http://h/\u200a").encodedPath).isEqualTo("/%E2%80%8A")
    // zero-width space
    assertThat(parse("http://h/\u200b").encodedPath).isEqualTo("/%E2%80%8B")
    // zero-width non-joiner
    assertThat(parse("http://h/\u200c").encodedPath).isEqualTo("/%E2%80%8C")
    // zero-width joiner
    assertThat(parse("http://h/\u200d").encodedPath).isEqualTo("/%E2%80%8D")
    // left-to-right mark

   */
  internal var allocationLimit = 1
    private set

  /** Current calls carried by this connection. */
  val calls = mutableListOf<Reference<RealCall>>()

  /** Timestamp when `allocations.size()` reached zero. Also assigned upon initial connection. */
  var idleAtNs = Long.MAX_VALUE

  /**
   * Returns true if this is an HTTP/2 connection. Such connections can be used in multiple HTTP
   * requests simultaneously.
   */

    assertThat("Thu, 01 Jan 1970 00:00 GMT".toHttpDateOrNull()).isNull()
    // Extra spaces treated as bad.
    assertThat("Thu,  01 Jan 1970 00:00 GMT".toHttpDateOrNull()).isNull()
    // Missing leading zero treated as bad.
    assertThat("Thu, 1 Jan 1970 00:00 GMT".toHttpDateOrNull()).isNull()

    // RFC 850, obsoleted by RFC 1036 with any TZ.
    assertThat("Thursday, 01-Jan-1970 00:00:00 GMT-01:00".toHttpDateOrNull()!!.time)

2000..200A    ; disallowed_STD3_mapped ; 0020          # 1.1  EN QUAD..HAIR SPACE
200B          ; ignored                                # 1.1  ZERO WIDTH SPACE
200C..200D    ; deviation              ;               # 1.1  ZERO WIDTH NON-JOINER..ZERO WIDTH JOINER
200E..200F    ; disallowed                             # 1.1  LEFT-TO-RIGHT MARK..RIGHT-TO-LEFT MARK

      assertThat(header.constructed).isFalse()
      assertThat(header.length).isEqualTo(201)
    }

    assertThat(derReader.hasNext()).isFalse()
  }

  @Test fun `decode length encoded with leading zero byte`() {
    val buffer =
      Buffer()
        .writeByte(0b00000010)
        .writeByte(0b10000010)
        .writeByte(0b00000000)
        .writeByte(0b01111111)

    val derReader = DerReader(buffer)

   2002; EN SPACE
   2003; EM SPACE
   2004; THREE-PER-EM SPACE
   2005; FOUR-PER-EM SPACE
   2006; SIX-PER-EM SPACE
   2007; FIGURE SPACE
   2008; PUNCTUATION SPACE
   2009; THIN SPACE
   200A; HAIR SPACE
   200B; ZERO WIDTH SPACE
   202F; NARROW NO-BREAK SPACE
   205F; MEDIUM MATHEMATICAL SPACE

    `BufferedSource.toResponseBody()` to `BufferedSource.asResponseBody()`. If the returned value
    is a view of what created it, we use _as_.
 *  Fix: Permit response codes of zero for compatibility with OkHttp 3.x.
 *  Fix: Change the return type of `MockWebServer.takeRequest()` to be nullable.
 *  Fix: Make `Call.clone()` public to Kotlin callers.


## Version 4.0.0-RC1

_2019-06-03_

  }

  /** For example, empty Protobuf RPC messages end up as a zero-length POST.  */
  @Test
  fun zeroLengthPost() {
    zeroLengthPayload("POST")
  }

  @Test
  fun zeroLengthPost_HTTP_2() {
    enableProtocol(Protocol.HTTP_2)
    zeroLengthPost()
  }

  /** For example, creating an Amazon S3 bucket ends up as a zero-length POST.  */
  @Test
  fun zeroLengthPut() {