public void testEmpty_write_noBytesBuffers_atNonZeroPosition() throws IOException {
      file.write(5, ImmutableList.of(buffer(""), buffer(""), buffer("")));
      assertContentEquals(bytes("00000"), file);
    }
Actual test cases for testing RegularFiles.
jimfs/src/test/java/com/google/common/jimfs/RegularFileTest.java