@VisibleForTesting
  CommandReturn getRawDiskInfo() throws IOException {
    return ShellUtils.execCommandWithOutput("df", "-k", "-P", "-T", mJournalPath);
  }
@Test
  public void testFailedInfo() throws IOException  {
    JournalSpaceMonitor monitor = Mockito.spy(
        new JournalSpaceMonitor(Paths.get(".").toAbsolutePath().toString(), 10));
    doThrow(new IOException("couldnt run")).when(monitor).getRawDiskInfo();
    assertThrows(IOException.class, monitor::getDiskInfo);
  }