From 64806cca28d17ff11c7a92a4ca865cd0ecca55d9 2016-06-02 18:03:58
From: Thomas Kluyver <takowl@gmail.com>
Date: 2016-06-02 18:03:58
Subject: [PATCH] Merge pull request #9527 from Carreau/simple-prompt-update-layout

Don't update PTK layout if --simple-shell
---

diff --git a/IPython/terminal/ptshell.py b/IPython/terminal/ptshell.py
index 8af3627..cf7fac1 100644
--- a/IPython/terminal/ptshell.py
+++ b/IPython/terminal/ptshell.py
@@ -152,6 +152,7 @@ class TerminalInteractiveShell(InteractiveShell):
             toggle_set_term_title(False)
 
     def init_prompt_toolkit_cli(self):
+        self._app = None
         if self.simple_prompt:
             # Fall back to plain non-interactive output for tests.
             # This is very limited, and only accepts a single line.
@@ -300,7 +301,8 @@ class TerminalInteractiveShell(InteractiveShell):
         Ask for a re computation of the application layout, if for example ,
         some configuration options have changed.
         """
-        self._app.layout = create_prompt_layout(**self._layout_options())
+        if self._app:
+            self._app.layout = create_prompt_layout(**self._layout_options())
 
     def prompt_for_code(self):
         document = self.pt_cli.run(