| 1 | import unittest |
| 2 | |
| 3 | import numpy as np |
| 4 | |
| 5 | from compare_scroll import compare |
| 6 | |
| 7 | |
| 8 | class ScrollTests(unittest.TestCase): |
| 9 | def test_overlap_ignores_blank_rows_and_survives_a_changed_caret(self): |
| 10 | page = np.full((120, 20, 3), 255, dtype=np.uint8) |
| 11 | for y in range(0, len(page), 3): |
| 12 | page[y, 2:8] = [y, 40, 80] |
| 13 | before, after = page[:90].copy(), page[30:].copy() |
| 14 | after[20:25, 12] = 0 |
| 15 | result = compare(before, after, 20) |
| 16 | self.assertEqual(result['scroll_y'], 30) |
| 17 | self.assertFalse(result['ambiguous']) |
| 18 | self.assertGreater(result['candidates'][0]['foreground_equal_fraction'], 0.95) |
| 19 | |
| 20 | def test_repeated_foreground_has_no_unique_offset(self): |
| 21 | image = np.full((40, 20, 3), 255, dtype=np.uint8) |
| 22 | image[::4, 2:8] = 0 |
| 23 | result = compare(image, image, 20) |
| 24 | self.assertTrue(result['ambiguous']) |
| 25 | self.assertIsNone(result['scroll_y']) |
| 26 | |
| 27 | def test_blank_or_unrelated_images_cannot_establish_scroll(self): |
| 28 | white = np.full((40, 20, 3), 255, dtype=np.uint8) |
| 29 | with self.assertRaises(ValueError): |
| 30 | compare(white, white, 20) |
| 31 | before, after = white.copy(), white.copy() |
| 32 | before[:, 2:8] = [30, 40, 80] |
| 33 | after[:, 2:8] = [31, 40, 80] |
| 34 | with self.assertRaises(ValueError): |
| 35 | compare(before, after, 20) |
| 36 | with self.assertRaises(ValueError): |
| 37 | compare(before, after[:-1], 20) |
| 38 | |
| 39 | |
| 40 | if __name__ == '__main__': |
| 41 | unittest.main() |