Issue 2091: duration of task is set to a wrong and extremely big value

- Thanks to Wray Zheng.

AUTHORS

@@ -337,3 +337,4 @@ suggestions:
   tom-doerr
   ad-si
   Adrien Lemaire
+  Wray Zheng

ChangeLog

@@ -111,6 +111,8 @@
            Thanks to Chad Phillips
 - #2176    How to get the full list of tags ?
            Thanks to Adrien Lemaire
+- #2091    duration of task is set to a wrong and extremely big value
+           Thanks to Wray Zheng
 - Added 'juhannus' as a synonym for 'midsommarafton'
            Thanks to Lynoure Braakman
 - Deprecated the 'DUETODAY' virtual tag, which is a synonym for the 'TODAY'

src/feedback.cpp

@@ -170,10 +170,14 @@ std::string taskInfoDifferences (
     }
     else if (name == "start")
     {
-      out << format ("{1} deleted (duration: {2}).",
-                     Lexer::ucFirst (name),
-                     Duration (current_timestamp - last_timestamp).format ())
-          << "\n";
+      if (last_timestamp > 0)
+        out << format ("{1} deleted (duration: {2}).",
+                       Lexer::ucFirst (name),
+                       Duration (current_timestamp - last_timestamp).format ())
+            << "\n";
+      else
+        out << format ("{1} deleted.", Lexer::ucFirst (name))
+            << "\n";
     }
     else
     {