*  Fix: Forbid spaces in header names.
 *  Fix: Don't offer to do gzip if the request is partial.
 *  Fix: MockWebServer is now usable with JUnit 5. That update [broke the rules][junit_5_rules].
 *  New: Support `Expect: 100-continue` as a request header. Callers can use this header to
    pessimistically hold off on transmitting a request body until a server gives the go-ahead.

    val executeAtNanos = System.nanoTime()
    assertFailsWith<StreamResetException> {
      call.execute()
    }.also { expected ->
      assertThat(expected.message).isEqualTo(
        "stream was reset: PROTOCOL_ERROR",
      )
    }
    val elapsedUntilFailure = System.nanoTime() - executeAtNanos
    assertThat(TimeUnit.NANOSECONDS.toMillis(elapsedUntilFailure).toDouble())
      .isCloseTo(1000.0, 250.0)

      if (pos == limit) {
        // Empty path: keep the base path as-is.
        return
      }
      val c = input[pos]
      if (c == '/' || c == '\\') {
        // Absolute path: reset to the default "/".
        encodedPathSegments.clear()
        encodedPathSegments.add("")
        pos++
      } else {
        // Relative path: clear everything after the last '/'.

    sink1.writeUtf8("abc")
    assertFailsWith<IOException> {
      sink2.writeUtf8("abc")
      sink2.flush()
    }.also { expected ->
      assertThat(expected.message).isEqualTo("stream was reset: REFUSED_STREAM")
    }
    sink1.writeUtf8("def")
    sink1.close()
    assertFailsWith<ConnectionShutdownException> {
      connection.newStream(headerEntries("c", "cola"), true)
    }