Fix tests. Also do an image comparison test.

colour/plotting/tm3018/tests/test_report.py

@@ -1,16 +1,21 @@
 # !/usr/bin/env python
 """Define the unit tests for the :mod:`colour.plotting.tm3018.report` module."""
 
+import os
 import unittest
+from matplotlib.backends.backend_agg import FigureCanvasAgg
 from matplotlib.pyplot import Axes, Figure
+import numpy as np
 
 from colour.colorimetry import SDS_ILLUMINANTS
+from colour.io.image import read_image
 from colour.plotting.tm3018.report import (
     plot_single_sd_colour_rendition_report_full,
     plot_single_sd_colour_rendition_report_intermediate,
     plot_single_sd_colour_rendition_report_simple,
     plot_single_sd_colour_rendition_report,
 )
+from colour.utilities.array import as_array
 
 __author__ = "Colour Developers"
 __copyright__ = "Copyright 2013 Colour Developers"
@@ -103,10 +108,31 @@ def test_plot_single_sd_colour_rendition_report(self):
         figure, axes = plot_single_sd_colour_rendition_report(
             SDS_ILLUMINANTS["FL2"]
         )
-
         self.assertIsInstance(figure, Figure)
         self.assertIsInstance(axes, Axes)
 
+        canvas = FigureCanvasAgg(figure)
+        canvas.draw()
+
+        test_img = as_array(canvas.buffer_rgba()) / 255
+
+        ROOT_RESOURCES: str = os.path.join(
+            os.path.dirname(__file__), "resources"
+        )
+
+        ref_image_path = os.path.join(
+            ROOT_RESOURCES, "TM30_Report_Example.png"
+        )
+        ref_image = read_image(ref_image_path)
+
+        np.testing.assert_allclose(
+            ref_image,
+            test_img,
+            err_msg="TM30 Report Image Changed",
+            atol=1 / 255,
+            rtol=0,
+        )
+
 
 if __name__ == "__main__":
     unittest.main()