*  Fix: Don't crash with a `NullPointerException` if a server sends a close while we're sending a
    ping. OkHttp had a race condition bug.


## Version 4.6.0

_2020-04-28_

 *  Fix: Follow HTTP 307 and 308 redirects on methods other than GET and POST. We're reluctant to
    change OkHttp's behavior in handling common HTTP status codes, but this fix is overdue! The new

    return Integer.MAX_VALUE
  }

  companion object {
    /**
     * How many redirects and auth challenges should we attempt? Chrome follows 21 redirects; Firefox,
     * curl, and wget follow 20; Safari follows 16; and HTTP/1.0 recommends 5.
     */
    private const val MAX_FOLLOW_UPS = 20
  }

          ConnectResult(this, nextPlan = connectTcpNextPlan, throwable = IOException("canceled"))
        }
        connectTcpNextPlan != null -> {
          events += "plan $id needs follow-up"
          ConnectResult(this, nextPlan = connectTcpNextPlan)
        }
        else -> {
          events += "plan $id TCP connected"
          connectState = ConnectState.TCP_CONNECTED

        .build()
    assertFailsWith<IOException> {
      client.newCall(Request.Builder().url(server.url("/0")).build()).execute()
    }.also { expected ->
      assertThat(expected.message).isEqualTo("Too many follow-up requests: 21")
    }
  }

  /**
   * We had a bug where we were passing a null route to the authenticator.
   * https://github.com/square/okhttp/issues/3809
   */
  @Test

      apply {
        this.authenticator = authenticator
      }

    /** Configure this client to follow redirects. If unset, redirects will be followed. */
    fun followRedirects(followRedirects: Boolean) =
      apply {
        this.followRedirects = followRedirects
      }

    /**
     * Configure this client to allow protocol redirects from HTTPS to HTTP and from HTTP to HTTPS.

   *
   * We get plan0 and plan1 from the route planner.
   * We get plan2 as a follow-up to plan1, typically retry the same IP but different TLS.
   * We get plan3 as a retry of plan0, which was canceled when it lost the race.
   *
   * This test confirms that we prefer to do the TLS follow-up (plan2) before the TCP retry (plan3).
   * It also confirms we enforce the 250 ms delay in each race.
   */
  @Test

    // Cause the cache trim job to fail.
    filesystem.setFaultyDelete(cacheDir / "a.0", true)
    taskFaker.runNextTask()

    // Confirm we still allow snapshot reads after a trim failure.
    assertValue("a", "aa", "aa")
    assertValue("b", "bb", "bbb")

    // Allow the test to clean up.
    filesystem.setFaultyDelete(cacheDir / "a.0", false)
  }

  @ParameterizedTest

 * and the last 7 bits from this byte.
 *
 * The end of the range is not encoded, but can be inferred by looking at the start of the range
 * that follows.
 *
 * b1
 * --
 *
 * This is either a mapping decision or the length of the mapped output, according to this table:
 *
 * ```
 *  0..63 : Length of the UTF-16 sequence that this range maps to. The offset is b2b3.

    server.enqueue(
      MockResponse.Builder()
        .addHeader("Allow: GET, HEAD")
        .addHeader("Last-Modified: " + formatDate(-1, TimeUnit.HOURS))
        .addHeader("Cache-Control: max-age=0")
        .body("A")
        .build(),
    )
    server.enqueue(
      MockResponse.Builder()
        .addHeader("Allow: GET, HEAD, PUT")
        .code(HttpURLConnection.HTTP_NOT_MODIFIED)

   * provides support.
   */
  QUIC("quic"),

  /**
   * HTTP/3 is the third and upcoming major version of the Hypertext Transfer Protocol used to
   * exchange information. HTTP/3 runs over QUIC, which is published as RFC 9000.
   *
   * HTTP/3 is not natively supported by OkHttp, but provided to allow a theoretical interceptor
   * that provides support.