qtconsole: fix race-cond, handle multiple exec

	fix race condition in qtconsole due to a race condition beween the population
	of the magic menu and the first prompt request. Resolved by upgrading the
	logic of the console to handle several executions request in parallel.

	Some namedTuple might still carry redundent information but the fix is the
	first priority

	fixes  #1057 , introduced by  #956

IPython/frontend/qt/console/frontend_widget.py

@@ -138,6 +138,7 b' class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):'
         self._input_splitter = self._input_splitter_class(input_mode='cell')
         self._kernel_manager = None
         self._request_info = {}
+        self._request_info['execute'] = {};
         self._callback_dict = {}
 
         # Configure the ConsoleWidget.
@@ -199,7 +200,7 b' class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):'
         See parent class :meth:`execute` docstring for full details.
         """
         msg_id = self.kernel_manager.shell_channel.execute(source, hidden)
-        self._request_info['execute'] = self._ExecutionRequest(msg_id, 'user')
+        self._request_info['execute'][msg_id] = self._ExecutionRequest(msg_id, 'user')
         self._hidden = hidden
         if not hidden:
             self.executing.emit(source)
@@ -343,7 +344,7 b' class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):'
         msg_id = self.kernel_manager.shell_channel.execute('',
             silent=True, user_expressions={ local_uuid:expr })
         self._callback_dict[local_uuid] = callback
-        self._request_info['execute'] = self._ExecutionRequest(msg_id, 'silent_exec_callback')
+        self._request_info['execute'][msg_id] = self._ExecutionRequest(msg_id, 'silent_exec_callback')
 
     def _handle_exec_callback(self, msg):
         """Execute `callback` corresonding to `msg` reply, after ``_silent_exec_callback``
@@ -373,12 +374,14 b' class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):'
         """ Handles replies for code execution.
         """
         self.log.debug("execute: %s", msg.get('content', ''))
-        info = self._request_info.get('execute')
+        info_list = self._request_info.get('execute')
+        msg_id = msg['parent_header']['msg_id']
+        if msg_id in info_list:
+            info = info_list[msg_id]
         # unset reading flag, because if execute finished, raw_input can't
         # still be pending.
         self._reading = False
-        if info and info.id == msg['parent_header']['msg_id'] and \
-                info.kind == 'user' and not self._hidden:
+        if info and info.kind == 'user' and not self._hidden:
             # Make sure that all output from the SUB channel has been processed
             # before writing a new prompt.
             self.kernel_manager.sub_channel.flush()
@@ -400,8 +403,8 b' class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):'
 
             self._show_interpreter_prompt_for_reply(msg)
             self.executed.emit(msg)
-        elif info and info.id == msg['parent_header']['msg_id'] and \
-                info.kind == 'silent_exec_callback' and not self._hidden:
+            info_list.pop(msg_id)
+        elif info and info.kind == 'silent_exec_callback' and not self._hidden:
             self._handle_exec_callback(msg)
         else:
             super(FrontendWidget, self)._handle_execute_reply(msg)
@@ -559,7 +562,7 b' class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):'
         """
         if self._executing:
             self._executing = False
-            self._request_info['execute'] = None
+            self._request_info['execute'] = {}
         self._reading = False
         self._highlighter.highlighting_on = False
 

IPython/frontend/qt/console/history_console_widget.py

@@ -211,18 +211,20 b' class HistoryConsoleWidget(ConsoleWidget):'
                 'hlen':'len(get_ipython().history_manager.input_hist_raw)',
                 }
             )
-        self._request_info['execute'] = self._ExecutionRequest(msg_id, 'save_magic')
+        self._request_info['execute'][msg_id] = self._ExecutionRequest(msg_id, 'save_magic')
 
     def _handle_execute_reply(self, msg):
         """ Handles replies for code execution, here only session history length
         """
-        info = self._request_info.get('execute')
-        if info and info.id == msg['parent_header']['msg_id'] and \
-                info.kind == 'save_magic' and not self._hidden:
-            content = msg['content']
-            status = content['status']
-            if status == 'ok':
-                self._max_session_history=(int(content['user_expressions']['hlen']))
+        info_list = self._request_info.get('execute')
+        msg_id = msg['parent_header']['msg_id']
+        if msg_id in info_list:
+            info = info_list.pop(msg_id)
+            if info.kind == 'save_magic' and not self._hidden:
+                content = msg['content']
+                status = content['status']
+                if status == 'ok':
+                    self._max_session_history=(int(content['user_expressions']['hlen']))
 
     def save_magic(self):
         # update the session history length

IPython/frontend/qt/console/ipython_widget.py

@@ -165,11 +165,14 b' class IPythonWidget(FrontendWidget):'
     def _handle_execute_reply(self, msg):
         """ Reimplemented to support prompt requests.
         """
-        info = self._request_info.get('execute')
-        if info and info.id == msg['parent_header']['msg_id']:
+        info_list = self._request_info.get('execute')
+        msg_id = msg['parent_header']['msg_id']
+        if msg_id in info_list:
+            info = info_list[msg_id]
             if info.kind == 'prompt':
                 number = msg['content']['execution_count'] + 1
                 self._show_interpreter_prompt(number)
+                info_list.pop(msg_id)
             else:
                 super(IPythonWidget, self)._handle_execute_reply(msg)
 
@@ -358,7 +361,7 b' class IPythonWidget(FrontendWidget):'
         if number is None:
             msg_id = self.kernel_manager.shell_channel.execute('', silent=True)
             info = self._ExecutionRequest(msg_id, 'prompt')
-            self._request_info['execute'] = info
+            self._request_info['execute'][msg_id] = info
             return
 
         # Show a new prompt and save information about it so that it can be

IPython/frontend/qt/console/mainwindow.py

@@ -629,6 +629,9 b' class MainWindow(QtGui.QMainWindow):'
         self.pop = QtGui.QAction("&Update All Magic Menu ",
             self, triggered=self.update_all_magic_menu)
         self.add_menu_action(self.all_magic_menu, self.pop)
+        # we need to populate the 'Magic Menu' once the kernel has answer at
+        # least once let's do it immedialy, but it's assured to works
+        self.pop.trigger()
 
         self.reset_action = QtGui.QAction("&Reset",
             self,

IPython/frontend/qt/console/qtconsoleapp.py

@@ -452,9 +452,6 b' class IPythonQtConsoleApp(BaseIPythonApplication):'
         self.window.add_tab_with_frontend(self.widget)
         self.window.init_menu_bar()
 
-        # we need to populate the 'Magic Menu' once the kernel has answer at least once
-        self.kernel_manager.shell_channel.first_reply.connect(self.window.pop.trigger)
-
         self.window.setWindowTitle('Python' if self.pure else 'IPython')
 
     def init_colors(self):