TST: Add a test for FT2Image

QuLogic · QuLogic · commit 2c3cae2c610e · 2024-08-24T03:32:38.000-04:00
The only externally-available API here is `draw_rect_filled` and
conversion to NumPy arrays via the buffer protocol.
diff --git a/lib/matplotlib/tests/test_ft2font.py b/lib/matplotlib/tests/test_ft2font.py
@@ -1,6 +1,8 @@
-from pathlib import Path
+import itertools
 import io
+from pathlib import Path
 
+import numpy as np
 import pytest
 
 from matplotlib import ft2font
@@ -9,6 +11,24 @@
 import matplotlib.pyplot as plt
 
 
+def test_ft2image_draw_rect_filled():
+    width = 23
+    height = 42
+    for x0, y0, x1, y1 in itertools.product([1, 100], [2, 200], [4, 400], [8, 800]):
+        im = ft2font.FT2Image(width, height)
+        im.draw_rect_filled(x0, y0, x1, y1)
+        a = np.asarray(im)
+        assert a.dtype == np.uint8
+        assert a.shape == (height, width)
+        if x0 == 100 or y0 == 200:
+            # All the out-of-bounds starts should get automatically clipped.
+            assert np.sum(a) == 0
+        else:
+            # Otherwise, ends are clipped to the dimension, but are also _inclusive_.
+            filled = (min(x1 + 1, width) - x0) * (min(y1 + 1, height) - y0)
+            assert np.sum(a) == 255 * filled
+
+
 def test_fallback_errors():
     file_name = fm.findfont('DejaVu Sans')
 
