MAINT: tests: Fix test for update_form_fields3

Author: PJBrs

tests/test_writer.py

@@ -1735,25 +1735,20 @@ def test_update_form_fields3():
         url = "https://github.com/user-attachments/files/21073581/CERERE.INMATRICULARE.form.pdf"
         name = "iss3361.pdf"
         writer = PdfWriter()
+        output = BytesIO()
         writer.append(BytesIO(get_data_from_url(url, name=name)))
         data = {
             "subsemnatul": "Σὲ γνωρίζω ἀπὸ τὴν κόψη",
             "strada": "Căpitan Nicolae Licăreț",
             "adresa_judet": "Конференция",
         }
-        writer.update_page_form_field_values(writer.pages[0], data, auto_regenerate=False)
-        apstream_object = (writer.pages[0]["/Annots"][0]["/AP"]["/N"].get_data())
-        found_hex = "".join(re.findall(r"<(.*?)>", apstream_object.decode()))
-        expected_hex = data["subsemnatul"].encode("utf-16-be").hex()
-        assert expected_hex in found_hex
-        apstream_object = (writer.pages[0]["/Annots"][7]["/AP"]["/N"].get_data())
-        found_hex = re.findall(r"<(.*?)>", apstream_object.decode())
-        expected_hex = data["strada"].encode("utf-16-be").hex()
-        assert expected_hex in found_hex
-        apstream_object = (writer.pages[0]["/Annots"][9]["/AP"]["/N"].get_data())
-        found_hex = re.findall(r"<(.*?)>", apstream_object.decode())
-        expected_hex = data["adresa_judet"].encode("utf-16-be").hex()
-        assert expected_hex in found_hex
+        writer.update_page_form_field_values(writer.pages[0], data, auto_regenerate=False, flatten=True)
+        writer.write(output)
+        output.seek(0)
+        reader = PdfReader(output)
+        extracted_text = reader.pages[0].extract_text()
+        for expected_value in data.values():
+            assert expected_value in extracted_text
 
 
 @pytest.mark.enable_socket