BUG: QtKernelManagerMixin does not define PyQt4-safe signals.

IPython/frontend/qt/base_kernelmanager.py

@@ -5,8 +5,8 b''
 from IPython.external.qt import QtCore
 
 # IPython imports.
-from IPython.utils.traitlets import Type
-from util import SuperQObject
+from IPython.utils.traitlets import HasTraits, Type
+from util import MetaQObjectHasTraits, SuperQObject
 
 
 class ChannelQObject(SuperQObject):
@@ -189,10 +189,12 b' class QtHBChannelMixin(ChannelQObject):'
         self.kernel_died.emit(since_last_heartbeat)
 
 
-class QtKernelManagerMixin(object):
+class QtKernelManagerMixin(HasTraits, SuperQObject):
     """ A KernelManager that provides signals and slots.
     """
 
+    __metaclass__ = MetaQObjectHasTraits
+
     # Emitted when the kernel manager has started listening.
     started_kernel = QtCore.Signal()
 

IPython/frontend/qt/embedded_kernelmanager.py

@@ -8,7 +8,6 b' from IPython.embedded.kernelmanager import \\'
 from IPython.utils.traitlets import Type
 from base_kernelmanager import QtShellChannelMixin, QtSubChannelMixin, \
     QtStdInChannelMixin, QtHBChannelMixin, QtKernelManagerMixin
-from util import MetaQObjectHasTraits, SuperQObject
 
 
 class QtShellEmbeddedChannel(QtShellChannelMixin, ShellEmbeddedChannel):
@@ -24,13 +23,10 b' class QtHBEmbeddedChannel(QtHBChannelMixin, HBEmbeddedChannel):'
     pass
 
 
-class QtEmbeddedKernelManager(QtKernelManagerMixin,
-                              EmbeddedKernelManager, SuperQObject):
+class QtEmbeddedKernelManager(QtKernelManagerMixin, EmbeddedKernelManager):
     """ An embedded KernelManager that provides signals and slots.
     """
 
-    __metaclass__ = MetaQObjectHasTraits
-
     sub_channel_class = Type(QtSubEmbeddedChannel)
     shell_channel_class = Type(QtShellEmbeddedChannel)
     stdin_channel_class = Type(QtStdInEmbeddedChannel)

IPython/frontend/qt/kernelmanager.py

@@ -7,7 +7,6 b' from IPython.zmq.kernelmanager import ShellSocketChannel, SubSocketChannel, \\'
     StdInSocketChannel, HBSocketChannel, KernelManager
 from base_kernelmanager import QtShellChannelMixin, QtSubChannelMixin, \
     QtStdInChannelMixin, QtHBChannelMixin, QtKernelManagerMixin
-from util import MetaQObjectHasTraits, SuperQObject
 
 
 class QtShellSocketChannel(QtShellChannelMixin, ShellSocketChannel):
@@ -23,12 +22,10 b' class QtHBSocketChannel(QtHBChannelMixin, HBSocketChannel):'
     pass
 
 
-class QtKernelManager(QtKernelManagerMixin, KernelManager, SuperQObject):
+class QtKernelManager(QtKernelManagerMixin, KernelManager):
     """ A KernelManager that provides signals and slots.
     """
 
-    __metaclass__ = MetaQObjectHasTraits
-
     sub_channel_class = Type(QtSubSocketChannel)
     shell_channel_class = Type(QtShellSocketChannel)
     stdin_channel_class = Type(QtStdInSocketChannel)

IPython/frontend/qt/util.py

@@ -56,7 +56,7 b' class SuperQObject(QtCore.QObject):'
     they don't inherit QObject.)
 
     This class is primarily useful for attaching signals to existing non-Qt
-    classes. See QtKernelManager for an example.
+    classes. See QtKernelManagerMixin for an example.
     """
 
     def __new__(cls, *args, **kw):