BUG: append() fails when articles do not have /T

pypdf/_writer.py

@@ -3085,7 +3085,11 @@ def add_filtered_articles(
         for p in pages.values():
             pp = p.original_page
             for a in pp.get("/B", ()):
-                thr = a.get_object()["/T"]
+                thr = a.get_object().get("/T")
+                if thr is None:
+                    continue
+                else:
+                    thr = thr.get_object()
                 if thr.indirect_reference.idnum not in self._id_translated[
                     id(reader)
                 ] and fltr.search(thr["/I"]["/Title"]):

tests/test_writer.py

@@ -1589,3 +1589,13 @@ def test_missing_info():
 
     writer = PdfWriter(clone_from=reader)
     assert len(writer.pages) == len(reader.pages)
+
+
+@pytest.mark.enable_socket()
+def test_no_t_in_articles():
+    """Cf #2078"""
+    url = "https://github.com/py-pdf/pypdf/files/12311735/bad.pdf"
+    name = "iss2078.pdf"
+    reader = PdfReader(BytesIO(get_data_from_url(url, name=name)))
+    writer = PdfWriter()
+    writer.append(reader)