###############################################################################
#
# Tests for XlsxWriter.
#
# SPDX-License-Identifier: BSD-2-Clause
#
# Copyright (c), 2013-2025, John McNamara, jmcnamara@cpan.org
#

import unittest
from io import StringIO

from xlsxwriter.drawing import Drawing


class TestWriteCchart(unittest.TestCase):
    """
    Test the Drawing _write_c_chart() method.

    """

    def setUp(self):
        self.fh = StringIO()
        self.drawing = Drawing()
        self.drawing._set_filehandle(self.fh)

    def test_write_c_chart(self):
        """Test the _write_c_chart() method"""

        self.drawing._write_c_chart("rId1")

        exp = """<c:chart xmlns:c="http://schemas.openxmlformats.org/drawingml/2006/chart" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships" r:id="rId1"/>"""
        got = self.fh.getvalue()

        self.assertEqual(exp, got)
