Add tests for resize_png()

Author: mhhd2020

tests/unit/test_helpers.py

@@ -1,9 +1,51 @@
+from io import BytesIO
 from pathlib import Path
 
+import pytest
+from PIL import Image
+
 from sketch_map_tool import helpers
 
 
 def test_get_project_root():
     expected = Path(__file__).resolve().parent.parent.parent.resolve()
     result = helpers.get_project_root()
     assert expected == result
+
+
+@pytest.mark.parametrize(
+    ("max_length", "width_exp", "height_exp"),
+    [
+        (1450, 1450, 1232),  # One dimension too big
+        (1000, 1000, 850),  # Both dimensions too big
+        (1456, 1456, 1238),  # Not too big, exactly limit
+        (1600, 1456, 1238),  # Not too big, smaller than limit
+    ],
+)
+def test_resize_png(map_frame_buffer, max_length, width_exp, height_exp):
+    img = Image.open(map_frame_buffer)
+    img_rotated = img.rotate(90, expand=1)
+    width, height = img.width, img.height
+    width_rotated, height_rotated = img_rotated.width, img_rotated.height
+    assert width == 1456 and height == 1238
+    assert width_rotated == 1238 and height_rotated == 1456
+
+    img_rotated_buffer = BytesIO()
+    img_rotated.save(img_rotated_buffer, format="png")
+    img_rotated_buffer.seek(0)
+
+    img_resized_buffer = helpers.resize_png(map_frame_buffer, max_length=max_length)
+    img_rotated_resized_buffer = helpers.resize_png(
+        img_rotated_buffer, max_length=max_length
+    )
+    img_resized = Image.open(img_resized_buffer)
+    img_rotated_resized = Image.open(img_rotated_resized_buffer)
+
+    width_resized, height_resized = img_resized.width, img_resized.height
+    width_rotated_resized, height_rotated_resized = (
+        img_rotated_resized.width,
+        img_rotated_resized.height,
+    )
+
+    assert width_resized == width_exp and height_resized == height_exp
+    assert width_rotated_resized == height_exp and height_rotated_resized == width_exp