WIP: add a test

Tests/test_file_cur.py

@@ -19,3 +19,12 @@ def test_invalid_file():
 
     with pytest.raises(SyntaxError, match="No images were found"):
         CurImagePlugin.CurImageFile("Tests/images/no_cursors.cur")
+
+
+def test_1bit_transparency():
+    with Image.open("Tests/images/cur_259.cur") as im:
+        assert im.size == (32, 32) and im.mode == "RGBA"
+        assert im.getpixel((0, 0)) == (0, 0, 0, 255)  # pointy bit is black
+        assert im.getpixel((1, 0)) == (0, 0, 0, 255)  # and its neighbor is black
+        assert im.getpixel((2, 0)) == (0, 0, 0, 0)  # third pixel in the upper row is transparent though
+        assert im.getpixel((1, 1)) == (255, 255, 255, 255)  # cursor body is white