--- a/eric6/E5Gui/E5PathPicker.py	Wed Jun 17 17:12:21 2020 +0200
+++ b/eric6/E5Gui/E5PathPicker.py	Wed Jun 17 20:18:54 2020 +0200
@@ -135,8 +135,10 @@
         
         @param mode picker mode
         @type E5PathPickerModes
+        @exception ValueError raised to indicate a bad parameter value
         """
-        assert mode in E5PathPickerModes
+        if mode not in E5PathPickerModes:
+            raise ValueError("Bad value for 'mode' parameter.")
         
         oldMode = self.__mode
         self.__mode = mode