/** The snapshot to return from [next]. Null if we haven't computed that yet. */
      private var nextSnapshot: Snapshot? = null

      /** The snapshot to remove with [remove]. Null if removal is illegal. */
      private var removeSnapshot: Snapshot? = null

      override fun hasNext(): Boolean {
        if (nextSnapshot != null) return true

        synchronized(this@DiskLruCache) {

      Headers.Builder()
        .addUnsafeNonAscii("header1", "valué1")
        .build()
    assertThat(headers.toString()).isEqualTo("header1: valué1\n")
  }

  // Fails on JS, ClassCastException: Illegal cast
  @Test fun ofMapThrowsOnNull() {
    assertFailsWith<NullPointerException> {
      (mapOf("User-Agent" to null) as Map<String, String>).toHeaders()
    }
  }

  @Test fun toMultimapGroupsHeaders() {

    if (unknownValues) return false

    // If the server returned a value for client_max_window_bits, fail the web socket.
    if (clientMaxWindowBits != null) return false

    // If the server returned an illegal server_max_window_bits, fail the web socket.
    if (serverMaxWindowBits != null && serverMaxWindowBits !in 8..15) return false

    // Success.
    return true
  }

  @Throws(IOException::class)