From 49a40e7178598f958436d83c876d3e73c273b2d3 Mon Sep 17 00:00:00 2001
From: Damien Elmes <gpg@ankiweb.net>
Date: Sat, 30 Jan 2021 21:09:11 +1000
Subject: [PATCH] add missing check for on_done==None in with_progress()

---
 qt/aqt/taskman.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/qt/aqt/taskman.py b/qt/aqt/taskman.py
index 6f976838b..fa103199f 100644
--- a/qt/aqt/taskman.py
+++ b/qt/aqt/taskman.py
@@ -73,7 +73,8 @@ class TaskManager(QObject):
 
         def wrapped_done(fut):
             self.mw.progress.finish()
-            on_done(fut)
+            if on_done:
+                on_done(fut)
 
         self.run_in_background(task, wrapped_done)