test(pdf): diagnose S01 metric mismatch without changing fidelity gates

docs/p10-entry-final/test_baseline_math.py

@@ -0,0 +1,29 @@
+import unittest
+from importlib.util import spec_from_file_location, module_from_spec
+from pathlib import Path
+spec = spec_from_file_location('baseline_math', Path(__file__).with_name('baseline-math.py'))
+module = module_from_spec(spec); spec.loader.exec_module(module)
+
+
+class BaselineMathTests(unittest.TestCase):
+    def test_metric_offset_is_not_a_baseline_shift(self):
+        result = module.compare(56, 92, 92, 67, 100/3, -250)
+        self.assertGreater(result['oldCellDeltaMm'], 2)
+        self.assertEqual(result['baselineDeltaMm'], 0)
+        self.assertAlmostEqual(result['cellFormulaResidualPx'], 0)
+
+    def test_actual_render_shift_still_exceeds_same_two_mm_bound(self):
+        result = module.compare(56, 92, 112, 87, 100/3, -250)
+        self.assertGreater(result['baselineDeltaMm'], 2)
+
+    def test_descriptor_sign_is_normalised_like_installed_pdfminer(self):
+        self.assertEqual(module.compare(56,92,92,67,100/3,250), module.compare(56,92,92,67,100/3,-250))
+
+    def test_wrong_font_cell_metadata_is_detected(self):
+        self.assertGreater(module.compare(56,92,92,60,100/3,-250)['cellFormulaResidualPx'], 1)
+
+    def test_exact_physical_unit_conversion(self):
+        self.assertAlmostEqual(module.MM_PER_PIXEL * 96, 25.4)
+
+
+if __name__ == '__main__': unittest.main(verbosity=2)