Fix passing user_ns to IPython.start_ipython()

IPython/core/shellapp.py

@@ -198,6 +198,10 b' class InteractiveShellApp(Configurable):'
     )
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC')
 
+    def __init__(self, user_ns=None, **kwargs):
+        self.user_ns = user_ns
+        super(InteractiveShellApp, self).__init__(**kwargs)
+
     def init_path(self):
         """Add current working directory, '', to sys.path"""
         if sys.path[0] != '':

IPython/terminal/ipapp.py

@@ -334,7 +334,7 b' class TerminalIPythonApp(BaseIPythonApplication, InteractiveShellApp):'
         # so the banner shows *before* all extension loading stuff.
         self.shell = TerminalInteractiveShell.instance(parent=self,
                         display_banner=False, profile_dir=self.profile_dir,
-                        ipython_dir=self.ipython_dir)
+                        ipython_dir=self.ipython_dir, user_ns=self.user_ns)
         self.shell.configurables.append(self)
 
     def init_banner(self):