From 0456cf77fdbffa15c0c23aa16d7096fc2c994ee1 Mon Sep 17 00:00:00 2001
From: pubpub-zz <4083478+pubpub-zz@users.noreply.github.com>
Date: Tue, 5 Sep 2023 22:02:27 +0200
Subject: [PATCH] BUG : cope with extra space

closes #1903
---
 pypdf/_writer.py     |  1 +
 tests/test_writer.py | 14 ++++++++++++++
 2 files changed, 15 insertions(+)

diff --git a/pypdf/_writer.py b/pypdf/_writer.py
index dc132349e..5a197bff3 100644
--- a/pypdf/_writer.py
+++ b/pypdf/_writer.py
@@ -862,6 +862,7 @@ def _update_text_field(self, field: DictionaryObject) -> None:
         # Extract font information
         da = cast(str, field[AA.DA])
         font_properties = da.replace("\n", " ").replace("\r", " ").split(" ")
+        font_properties = [x for x in font_properties if x != ""]
         font_name = font_properties[font_properties.index("Tf") - 2]
         font_height = float(font_properties[font_properties.index("Tf") - 1])
         if font_height == 0:
diff --git a/tests/test_writer.py b/tests/test_writer.py
index 0d06f3f17..7c0af2049 100644
--- a/tests/test_writer.py
+++ b/tests/test_writer.py
@@ -1783,3 +1783,17 @@ def test_viewerpreferences():
     assert reader.viewer_preferences is None
     writer = PdfWriter(clone_from=reader)
     assert writer.viewer_preferences is None
+
+
+def test_extra_spaces_in_da_text(caplog):
+    writer = PdfWriter(clone_from=RESOURCE_ROOT / "form.pdf")
+    t = writer.pages[0]["/Annots"][0].get_object()["/DA"]
+    t = t.replace("/Helv", "/Helv   ")
+    writer.pages[0]["/Annots"][0].get_object()[NameObject("/DA")] = TextStringObject(t)
+    writer.update_page_form_field_values(
+        writer.pages[0], {"foo": "abcd"}, auto_regenerate=False
+    )
+    t = writer.pages[0]["/Annots"][0].get_object()["/AP"]["/N"].get_data()
+    assert "Font dictionary for  not found." not in caplog.text
+    assert b"/Helv" in t
+    assert b"(abcd)" in t