def set_bytes(self, b: bytes) -> None:
"""
Set bytes to this data element in the form of a string.
Not all implementations may support setting bytes (writing). See the
``writable`` method.
:param b: bytes to set.
:type b: bytes
:raises ReadOnlyError: This data element can only be read from / does
not support writing.
"""
if not self._readonly:
safe_file_write(self._filepath, b)
else:
raise ReadOnlyError("This file element is read only.")
def test_safe_file_write_absolute(
self, m_NTF: mock.MagicMock, m_remove: mock.MagicMock,
m_rename: mock.MagicMock, m_scd: mock.MagicMock) -> None:
# Experimental filepath and content.
fp = '/some/absolute/dir/bar.txt'
expected_bytes = 'hello world'
# Mock return for temp file creation so we can check os.* calls.
m_file = m_NTF.return_value
test_tmp_fp = 'temp fp'
m_file.name = test_tmp_fp
safe_file_write(fp, expected_bytes)
m_scd.assert_called_once_with('/some/absolute/dir')
m_NTF.assert_called_once_with(suffix='.txt', prefix='bar.',
dir='/some/absolute/dir', delete=False)
m_file.write.assert_called_once_with(expected_bytes)
m_file.__exit__.assert_called_once_with(None, None, None)
self.assertEqual(m_remove.call_count, 0)
m_rename.assert_called_once_with(test_tmp_fp, fp)