[bugfix] Do not pass None to Timestamp.fromtimestampformat()

Bug: T354281
Change-Id: I1e612266e0f5b7b6a55cc99eb56e72bca3861261
---
M pywikibot/pagegenerators/_factory.py
1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/pywikibot/pagegenerators/_factory.py b/pywikibot/pagegenerators/_factory.py
index 80c8081..4de0b08 100644
--- a/pywikibot/pagegenerators/_factory.py
+++ b/pywikibot/pagegenerators/_factory.py
@@ -1,6 +1,6 @@
 """GeneratorFactory module wich handles pagegenerators options."""
 #
-# (C) Pywikibot team, 2008-2023
+# (C) Pywikibot team, 2008-2024
 #
 # Distributed under the terms of the MIT license.
 #
@@ -413,14 +413,13 @@
                             'positive int.'.format(start))
             return None
 
-        try:
-            end = pywikibot.Timestamp.fromtimestampformat(end)
-        except ValueError as err:
-            pywikibot.error(
-                f'{err}. End parameter has wrong format!')
-            return None
-        except TypeError:  # end is None
-            pass
+        if end is not None:
+            try:
+                end = pywikibot.Timestamp.fromtimestampformat(end)
+            except ValueError as err:
+                pywikibot.error(
+                    f'{err}. End parameter has wrong format!')
+                return None
 
         if start or end:
             pywikibot.info('Fetching log events in range: {} - {}.'

