BUG: Fix check box value which should be name object (#3124)

Relates to #3115.

Author: stefan6419846

pypdf/_writer.py

@@ -1112,6 +1112,7 @@ def update_page_form_field_values(
                         v = NameObject("/Off")
                     # other cases will be updated through the for loop
                     annotation[NameObject(AA.AS)] = v
+                    annotation[NameObject(FA.V)] = v
                 elif (
                     parent_annotation.get(FA.FT) == "/Tx"
                     or parent_annotation.get(FA.FT) == "/Ch"

tests/test_forms.py

@@ -0,0 +1,26 @@
+"""Test form-related functionality. Separate file to keep overview."""
+
+from io import BytesIO
+
+import pytest
+
+from pypdf import PdfReader, PdfWriter
+from tests import get_data_from_url
+
+
+@pytest.mark.enable_socket
+def test_form_button__v_value_should_be_name_object():
+    url = "https://github.com/user-attachments/files/18736500/blank-form.pdf"
+    name = "issue3115.pdf"
+    reader = PdfReader(BytesIO(get_data_from_url(url, name=name)))
+    writer = PdfWriter(clone_from=reader)
+    writer.update_page_form_field_values(
+        writer.pages[0],
+        {"Other": "/On"},
+        auto_regenerate=False,
+    )
+    stream = BytesIO()
+    writer.write(stream)
+
+    # Wrong: `/V (/On)`.
+    assert b"\n/V /On\n" in stream.getvalue()

tests/test_workflows.py

@@ -1035,7 +1035,7 @@ def test_inline_images():
 
 
 @pytest.mark.enable_socket
-def test_iss():
+def test_issue1899():
     url = "https://github.com/py-pdf/pypdf/files/11801077/lv2018tconv.pdf"
     name = "lv2018tconv.pdf"
     reader = PdfReader(BytesIO(get_data_from_url(url, name=name)))