miscs (Interro02) : horizontal cutting resolution

tests/test_splitting_geometry.py

@@ -0,0 +1,92 @@
+"""Compare extracted answers against the same Poppler view used for labels."""
+
+import tempfile
+import unittest
+from pathlib import Path
+
+import numpy as np
+import pymupdf
+from pdf2image import convert_from_path
+
+from copienator.commands.splitting_int import _render_split_outputs
+
+
+class SplittingGeometryTests(unittest.TestCase):
+    def make_source(self, path, rotation, cropped=True):
+        with pymupdf.open() as document:
+            page = document.new_page(width=800, height=1000)
+            # Asymmetric colours exercise both translation and orientation.
+            for row in range(20):
+                for column in range(8):
+                    colour = (row / 20, column / 8, (row + column) % 7 / 7)
+                    page.draw_rect(
+                        pymupdf.Rect(column * 100, row * 50,
+                                     (column + 1) * 100, (row + 1) * 50),
+                        color=None, fill=colour,
+                    )
+            page.insert_text((200, 500), "Middle of the answer")
+            if cropped:
+                page.set_cropbox(pymupdf.Rect(20, 80, 760, 920))
+            page.set_rotation(rotation)
+            document.save(path)
+
+    def assert_matches_preview(self, answer, preview, bounds):
+        actual = np.asarray(convert_from_path(answer, dpi=72)[0]).astype(float)
+        expected = np.asarray(preview.crop(bounds)).astype(float)
+        self.assertEqual(actual.shape, expected.shape)
+        self.assertLess(np.abs(actual - expected).mean(), 0.5)
+
+    def test_cropped_and_uncropped_pages_at_every_rotation(self):
+        visible = {
+            0: (20, 80, 760, 920),
+            90: (80, 20, 920, 760),
+            180: (40, 80, 780, 920),
+            270: (80, 40, 920, 780),
+        }
+        for rotation in (0, 90, 180, 270):
+            for cropped in (False, True):
+                for full_answer in (False, True):
+                    with self.subTest(rotation=rotation, cropped=cropped, full=full_answer):
+                        with tempfile.TemporaryDirectory() as temporary:
+                            root = Path(temporary)
+                            source = root / "copy.pdf"
+                            self.make_source(source, rotation, cropped)
+                            before = source.read_bytes()
+                            preview = convert_from_path(source, dpi=72, use_cropbox=False)[0]
+                            width, height = preview.size
+                            bounds = visible[rotation] if cropped else (0, 0, width, height)
+                            if full_answer:
+                                coordinates = [("A", 0, 0, 10, 0, 100)]
+                            else:
+                                coordinates = [("A", 0, 250, 260, 0, 100),
+                                               ("_", 0, 711, 721, 0, 100)]
+                                bounds = (bounds[0], max(bounds[1], height // 4),
+                                          bounds[2], min(bounds[3], height * 3 // 4))
+                            _render_split_outputs(source, coordinates, root)
+                            self.assert_matches_preview(root / "A.pdf", preview, bounds)
+                            self.assertEqual(source.read_bytes(), before)
+
+    def test_answer_continues_to_bottom_then_next_page(self):
+        with tempfile.TemporaryDirectory() as temporary:
+            root = Path(temporary)
+            source = root / "copy.pdf"
+            first = root / "first.pdf"
+            second = root / "second.pdf"
+            self.make_source(first, 180)
+            self.make_source(second, 0)
+            with pymupdf.open() as document:
+                for path in (first, second):
+                    with pymupdf.open(path) as part:
+                        document.insert_pdf(part)
+                document.save(source)
+            previews = convert_from_path(source, dpi=72, use_cropbox=False)
+            _render_split_outputs(source, [("A", 0, 700, 720, 0, 100),
+                                           ("_", 1, 211, 230, 500, 600)], root)
+            rendered = convert_from_path(root / "A.pdf", dpi=72)
+            self.assertEqual(len(rendered), 2)
+            for actual, preview, bounds in zip(rendered, previews,
+                                               [(40, 700, 780, 920), (20, 80, 760, 250)]):
+                expected = np.asarray(preview.crop(bounds)).astype(float)
+                actual = np.asarray(actual).astype(float)
+                self.assertEqual(actual.shape, expected.shape)
+                self.assertLess(np.abs(actual - expected).mean(), 0.5)