Keep empty answers in the final individual outputs.

tests/test_annotation_modifications.py

@@ -115,6 +115,29 @@ class ModificationTests(unittest.TestCase):
         self.assertFalse((self.output / "Empty.jpg").exists())
         self.assertFalse(read_json(self.output / "info.json")["Empty"]["not_empty"])
 
+    def test_retained_empty_scan_stays_empty_after_unrelated_edits_and_can_be_replaced(self):
+        self.images["Empty"] = Image.new("RGB", (100, 60), "white")
+        self.heights["Empty"] = 10
+        self.info["Empty"]["present"] = True
+        self.seed()
+        self.apply("Copie43 Ex 1 -> Ex 2|")
+        info = read_json(self.output / "info.json")
+        self.assertTrue((self.output / "Empty.jpg").is_file())
+        self.assertEqual(info["Empty"], self.info["Empty"])
+        with Image.open(self.output / "Concat.jpg") as image:
+            self.assertEqual(image.height, 120 + 180 + 40)
+        self.apply("Copie43 Ex 1 -> Empty")
+        self.assertTrue(read_json(self.output / "info.json")["Empty"]["not_empty"])
+        self.apply()
+        self.assertEqual(read_json(self.output / "info.json")["Empty"], self.info["Empty"])
+
+    def test_removed_body_is_absent_and_not_exported_as_an_empty_scan(self):
+        self.apply("Copie43 Ex 1 x> Ex 2")
+        info = read_json(self.output / "info.json")["Ex 1"]
+        self.assertFalse(info["present"])
+        self.assertFalse(info["not_empty"])
+        self.assertFalse((self.output / "Ex 1.jpg").exists())
+
     def test_invalid_file_does_not_apply_valid_first_instruction(self):
         before = {p.name: p.read_bytes() for p in self.output.iterdir() if p.is_file()}
         with self.assertRaises(CliError):

tests/test_answer_returns.py

@@ -57,8 +57,8 @@ class AnswerReturnTests(unittest.TestCase):
             ), patch.object(annotating, "make_base_image", side_effect=self.supplement):
                 publish_answer_returns(self.root, self.source, self.destination)
                 files = sorted((self.destination / "answers").glob("*.jpg"))
-                self.assertEqual([p.name for p in files], ["Ex 1.jpg", "Ex 2.jpg"])
-                with Image.open(files[0]) as image:
+                self.assertEqual([p.name for p in files], ["Empty.jpg", "Ex 1.jpg", "Ex 2.jpg"])
+                with Image.open(self.destination / "answers" / "Ex 1.jpg") as image:
                     self.assertEqual(image.size, (100, 30 + 20 * sum((context, question, solution))))
                     colors = []
                     if context:
@@ -212,7 +212,7 @@ class AnswerReturnTests(unittest.TestCase):
         )
         self.assertEqual(
             sorted(path.name for path in answers.iterdir()),
-            ["Ex 1.jpg", "Ex 2.jpg"],
+            ["Empty.jpg", "Ex 1.jpg", "Ex 2.jpg"],
         )
 
 
@@ -304,7 +304,7 @@ class CompiledMembershipTests(unittest.TestCase):
                 self.assertEqual(info["Empty"], {"present": True, "not_empty": False, "touched": False, "score": "0"})
                 self.assertEqual(info["Absent"], {"present": False, "not_empty": False, "touched": False, "score": ""})
                 self.assertEqual(info["Perfect"], {"present": True, "not_empty": True, "touched": False, "score": "4"})
-                self.assertNotIn("Empty", rendered)
+                self.assertIn("Empty", rendered)
                 for label in rendered:
                     self.assertTrue((output / f"{label}.jpg").is_file())
                 # Selective redo keeps unselected saved answers in the PDF,
@@ -316,6 +316,76 @@ class CompiledMembershipTests(unittest.TestCase):
                 self.assertTrue(read_json(output / "info.json")["Perfect"]["touched"])
                 self.assertFalse(read_json(output / "info.json")["Empty"]["not_empty"])
 
+    def test_real_empty_pdf_is_published_in_all_annotation_modes(self):
+        import fitz
+        from copienator.commands import reading_annotations as standard
+        for mode in ("Anot", "Bnot", "BGnot"):
+            with self.subTest(mode=mode), tempfile.TemporaryDirectory() as directory:
+                root = Path(directory)
+                workspace = EvaluationWorkspace(root)
+                (root / "labels").write_text("Empty\nAbsent\n")
+                pdf = root / "answer.pdf"
+                with fitz.open() as document:
+                    page = document.new_page(width=200, height=60)
+                    page.insert_text((10, 30), "Copied question only")
+                    document.save(pdf)
+                data = {"01": {"Empty": {"pdf_path": pdf, "coordinates": (0, 0),
+                    "result": {"score": 0, "error": "empty-answer", "feedback": []}}}}
+                if mode == "Anot":
+                    status = annotating.process_student("01", data["01"], root, ["Empty", "Absent"], True)
+                    self.assertEqual(status, "success")
+                elif mode == "Bnot":
+                    status = standard.apply_actions_and_regenerate(
+                        workspace, data, "01", [], None, ["Empty", "Absent"])
+                    self.assertEqual(status, 0)
+                else:
+                    status, _ = reader.apply_actions_and_regenerate_grouped(
+                        workspace, data, "01", [], {}, ["Empty", "Absent"])
+                    self.assertEqual(status, 0)
+                output = root / mode / "Copie01"
+                destination = root / "return"
+                destination.mkdir()
+                with patch.multiple(configuration, RETURN_ANSWERS_ENABLED=True,
+                                    RETURN_ANSWERS_CONTEXT=False, RETURN_ANSWERS_QUESTION=False,
+                                    RETURN_ANSWERS_SOLUTION=False):
+                    publish_answer_returns(root, output, destination)
+                self.assertEqual([p.name for p in (destination / "answers").iterdir()], ["Empty.jpg"])
+                with Image.open(destination / "answers" / "Empty.jpg") as image:
+                    self.assertGreater(image.height, 0)
+                    self.assertLess(image.convert("L").getextrema()[0], 100)
+                self.assertFalse(read_json(destination / "info.json")["Empty"]["not_empty"])
+                self.assertFalse((output / "Concat.jpg").exists())
+                self.assertFalse((output / "Concat_F.pdf").exists())
+
+    def test_bnot_recovers_empty_scans_missing_from_review_layout(self):
+        from copienator.commands import reading_annotations as standard
+        for only_empty in (False, True):
+            with self.subTest(only_empty=only_empty), tempfile.TemporaryDirectory() as directory:
+                workspace = EvaluationWorkspace(Path(directory))
+                output = workspace.root / "Bnot" / "Copie01"
+                output.mkdir(parents=True)
+                answer = workspace.root / "answer.pdf"
+                answer.touch()
+                labels = {"Empty": {"pdf_path": answer, "coordinates": (0, 0),
+                                    "result": {"score": 0, "error": "empty-answer"}}}
+                if not only_empty:
+                    labels["Full"] = {"pdf_path": answer, "coordinates": (0, 0),
+                                      "result": {"score": 4}}
+                    atomic_write_json(output / "bnote.json", {"images": [
+                        {"label": "Full", "hmin": 0, "hmax": 50, "header_height": 0}]})
+                with patch.object(annotating, "make_base_image", return_value=(None, 0, 0)), patch.object(
+                    annotating, "compose_label_image", return_value=(Image.new("RGB", (100, 50)), 0)
+                ) as render:
+                    status = standard.apply_actions_and_regenerate(
+                        workspace, {"01": labels}, "01", [], None, [*labels, "Absent"])
+                self.assertEqual(status, 0)
+                self.assertTrue(all(call.kwargs["with_empty"] for call in render.call_args_list))
+                self.assertTrue((output / "Empty.jpg").is_file())
+                self.assertFalse((output / "Absent.jpg").exists())
+                self.assertFalse(read_json(output / "info.json")["Empty"]["not_empty"])
+                self.assertEqual((output / "Concat.jpg").exists(), not only_empty)
+                self.assertFalse((output / "Concat_F.jpg").exists())
+
     def test_all_empty_removes_stale_concat_and_records_false(self):
         with tempfile.TemporaryDirectory() as directory:
             workspace = EvaluationWorkspace(Path(directory))
@@ -325,10 +395,17 @@ class CompiledMembershipTests(unittest.TestCase):
                 (output / name).write_bytes(b"stale")
             atomic_write_json(output / "touched.json", {"Empty": True})
             atomic_write_json(output / "answer_labels.json", ["Empty"])
-            status, _ = reader.apply_actions_and_regenerate_grouped(
-                workspace, {"01": {"Empty": {"result": {"score": 0, "error": "empty-answer"}}}},
-                "01", [], {}, ["Empty"]
-            )
+            answer = workspace.root / "answer.pdf"
+            answer.touch()
+            with patch.object(annotating, "make_base_image", return_value=(Image.new("RGB", (100, 50)), 0, 0)), patch.object(
+                annotating, "compose_label_image", return_value=(Image.new("RGB", (100, 50)), 0)
+            ):
+                status, _ = reader.apply_actions_and_regenerate_grouped(
+                    workspace, {"01": {"Empty": {"result": {"score": 0, "error": "empty-answer"},
+                        "pdf_path": answer, "coordinates": (0, 0)}}},
+                    "01", [], {}, ["Empty"]
+                )
+            self.assertTrue((output / "Empty.jpg").is_file())
             self.assertEqual(status, 0)
             self.assertEqual(read_json(output / "info.json"), {
                 "Empty": {"present": True, "not_empty": False, "touched": False, "score": "0"}