'Test the _write_sheet_data() method'

def test_assemble_xml_file(self):

    string_table = SharedStringTable()
    index = string_table._get_shared_string_index('neptune')
    self.assertEqual(index, 0)
    index = string_table._get_shared_string_index('neptune')
    self.assertEqual(index, 0)
    index = string_table._get_shared_string_index('neptune')
    self.assertEqual(index, 0)
    index = string_table._get_shared_string_index('mars')
    self.assertEqual(index, 1)
    index = string_table._get_shared_string_index('venus')
    self.assertEqual(index, 2)
    index = string_table._get_shared_string_index('mars')
    self.assertEqual(index, 1)
    index = string_table._get_shared_string_index('venus')
    self.assertEqual(index, 2)
    string_table._sort_string_data()
    fh = StringIO()
    sharedstrings = SharedStrings()
    sharedstrings._set_filehandle(fh)
    sharedstrings.string_table = string_table
    sharedstrings._assemble_xml_file()
    exp = _xml_to_list('\n                                                                <?xml    version="1.0"    encoding="UTF-8"    standalone="yes"?>\n                                                                <sst    xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"    count="7"    uniqueCount="3">\n                                                                        <si>\n                                                                                <t>neptune</t>\n                                                                        </si>\n                                                                        <si>\n                                                                                <t>mars</t>\n                                                                        </si>\n                                                                        <si>\n                                                                                <t>venus</t>\n                                                                        </si>\n                                                                </sst>\n                                                                ')
    got = _xml_to_list(fh.getvalue())
    self.assertEqual(got, exp)
