that are trusted to sign a server's certificate chain. `HandshakeCertificates` also works with
    mutual TLS where these roles are reversed.

    These classes make it possible to enable HTTPS in MockWebServer in [just a few lines of
    code][https_server_sample].

 *  **OkHttp now supports prior knowledge cleartext HTTP/2.** Enable this by setting
    `Protocol.H2_PRIOR_KNOWLEDGE` as the lone protocol on an `OkHttpClient.Builder`. This mode

    Assumptions.assumeFalse(windows) // Can't deleteContents while the journal is open.

    filesystem.deleteRecursively(cacheDir)
    assertThat(cache["a"]).isNull()
  }

  /**
   * We had a long-lived bug where [DiskLruCache.trimToSize] could infinite loop if entries
   * being edited required deletion for the operation to complete.
   */
  @ParameterizedTest
  @ArgumentsSource(FileSystemParamProvider::class)