From fde1eec1668b8d3b2d1e9b6b1fc2b7c6175f0885 2018-10-13 15:56:42
From: Matthias Bussonnier <bussonniermatthias@gmail.com>
Date: 2018-10-13 15:56:42
Subject: [PATCH] support simple prompt

---

diff --git a/IPython/terminal/prompts.py b/IPython/terminal/prompts.py
index 6b7b7cc..a108ca7 100644
--- a/IPython/terminal/prompts.py
+++ b/IPython/terminal/prompts.py
@@ -14,6 +14,8 @@ class Prompts(object):
         self.shell = shell
 
     def vi_mode(self):
+        if not hasattr(self.shell.pt_app, 'editing_mode'):
+            return ''
         if self.shell.pt_app.editing_mode == 'VI':
             return '['+str(self.shell.pt_app.app.vi_state.input_mode)[3:6]+'] '
         return ''