private static JimfsOutputStream newOutputStream(boolean append) {
    RegularFile file = regularFile(0);
    return new JimfsOutputStream(
        file, append, new FileSystemState(new FakeFileTimeSource(), Runnables.doNothing()));
  }
Tests for {@link JimfsOutputStream}.

@author Colin Decker
jimfs/src/test/java/com/google/common/jimfs/JimfsOutputStreamTest.java