setUp(parameters.first, parameters.second)
    while (taskFaker.isIdle()) {
      set("a", "a", "a")
      set("b", "b", "b")
    }

    // Cause the rebuild action to fail.
    filesystem.setFaultyRename(cacheDir / DiskLruCache.JOURNAL_FILE_BACKUP, true)
    taskFaker.runNextTask()

    // Don't allow edits under any circumstances.
    assertThat(cache.edit("a")).isNull()