foolscap internal error on Windows buildslave

[zooko]

​https://tahoe-lafs.org/buildbot-tahoe-lafs/builders/FreeStorm%20WinXP-x86%20py2.6/builds/90/steps/test/logs/test.log

2012-06-02 04:28:31.593Z [Negotiation,client] got banana ERROR from remote side: internal server error, see logs
2012-06-02 04:28:31.593Z [Negotiation,client] got banana ERROR from remote side: internal server error, see logs
2012-06-02 04:28:31.593Z [Negotiation,client] got banana ERROR from remote side: internal server error, see logs
2012-06-02 04:28:31.593Z [Negotiation,client] Unhandled Error
	Traceback (most recent call last):
	  File "c:\python26\lib\site-packages\twisted\trial\unittest.py", line 1269, in _wait
	    reactor.run()
	  File "c:\python26\lib\site-packages\twisted\internet\base.py", line 1169, in run
	    self.mainLoop()
	  File "c:\python26\lib\site-packages\twisted\internet\base.py", line 1181, in mainLoop
	    self.doIteration(t)
	  File "c:\python26\lib\site-packages\twisted\internet\selectreactor.py", line 144, in doSelect
	    _logrun(selectable, _drdw, selectable, method, dict)
	--- <exception caught here> ---
	  File "c:\python26\lib\site-packages\twisted\python\log.py", line 84, in callWithLogger
	    return callWithContext({"system": lp}, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\log.py", line 69, in callWithContext
	    return context.call({ILogContext: newCtx}, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\context.py", line 118, in callWithContext
	    return self.currentContext().callWithContext(ctx, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\context.py", line 81, in callWithContext
	    return func(*args,**kw)
	  File "c:\python26\lib\site-packages\twisted\internet\selectreactor.py", line 155, in _doReadOrWrite
	    self._disconnectSelectable(selectable, why, method=="doRead")
	  File "c:\python26\lib\site-packages\twisted\internet\posixbase.py", line 263, in _disconnectSelectable
	    selectable.connectionLost(f)
	  File "c:\python26\lib\site-packages\twisted\internet\tcp.py", line 433, in connectionLost
	    Connection.connectionLost(self, reason)
	  File "c:\python26\lib\site-packages\twisted\internet\tcp.py", line 277, in connectionLost
	    protocol.connectionLost(reason)
	  File "c:\python26\lib\site-packages\twisted\protocols\tls.py", line 460, in connectionLost
	    ProtocolWrapper.connectionLost(self, reason)
	  File "c:\python26\lib\site-packages\twisted\protocols\policies.py", line 123, in connectionLost
	    self.wrappedProtocol.connectionLost(reason)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\broker.py", line 253, in connectionLost
	    self.tub.connectionDropped(self)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\pb.py", line 1070, in connectionDropped
	    self._allConnectionsAreDisconnected.fire(self)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\observer.py", line 42, in fire
	    assert not self._fired
	exceptions.AssertionError: 
	
2012-06-02 04:28:31.937Z [Negotiation,client] got banana ERROR from remote side: internal server error, see logs
2012-06-02 04:28:31.937Z [Negotiation,client] got banana ERROR from remote side: internal server error, see logs
2012-06-02 04:28:31.937Z [Negotiation,client] Unhandled Error
	Traceback (most recent call last):
	  File "c:\python26\lib\site-packages\twisted\trial\unittest.py", line 1269, in _wait
	    reactor.run()
	  File "c:\python26\lib\site-packages\twisted\internet\base.py", line 1169, in run
	    self.mainLoop()
	  File "c:\python26\lib\site-packages\twisted\internet\base.py", line 1181, in mainLoop
	    self.doIteration(t)
	  File "c:\python26\lib\site-packages\twisted\internet\selectreactor.py", line 144, in doSelect
	    _logrun(selectable, _drdw, selectable, method, dict)
	--- <exception caught here> ---
	  File "c:\python26\lib\site-packages\twisted\python\log.py", line 84, in callWithLogger
	    return callWithContext({"system": lp}, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\log.py", line 69, in callWithContext
	    return context.call({ILogContext: newCtx}, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\context.py", line 118, in callWithContext
	    return self.currentContext().callWithContext(ctx, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\context.py", line 81, in callWithContext
	    return func(*args,**kw)
	  File "c:\python26\lib\site-packages\twisted\internet\selectreactor.py", line 155, in _doReadOrWrite
	    self._disconnectSelectable(selectable, why, method=="doRead")
	  File "c:\python26\lib\site-packages\twisted\internet\posixbase.py", line 263, in _disconnectSelectable
	    selectable.connectionLost(f)
	  File "c:\python26\lib\site-packages\twisted\internet\tcp.py", line 433, in connectionLost
	    Connection.connectionLost(self, reason)
	  File "c:\python26\lib\site-packages\twisted\internet\tcp.py", line 277, in connectionLost
	    protocol.connectionLost(reason)
	  File "c:\python26\lib\site-packages\twisted\protocols\tls.py", line 460, in connectionLost
	    ProtocolWrapper.connectionLost(self, reason)
	  File "c:\python26\lib\site-packages\twisted\protocols\policies.py", line 123, in connectionLost
	    self.wrappedProtocol.connectionLost(reason)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\broker.py", line 253, in connectionLost
	    self.tub.connectionDropped(self)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\pb.py", line 1070, in connectionDropped
	    self._allConnectionsAreDisconnected.fire(self)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\observer.py", line 42, in fire
	    assert not self._fired
	exceptions.AssertionError: 
	
2012-06-02 04:28:31.953Z [Negotiation,client] Unhandled Error
	Traceback (most recent call last):
	  File "c:\python26\lib\site-packages\twisted\trial\unittest.py", line 1269, in _wait
	    reactor.run()
	  File "c:\python26\lib\site-packages\twisted\internet\base.py", line 1169, in run
	    self.mainLoop()
	  File "c:\python26\lib\site-packages\twisted\internet\base.py", line 1181, in mainLoop
	    self.doIteration(t)
	  File "c:\python26\lib\site-packages\twisted\internet\selectreactor.py", line 144, in doSelect
	    _logrun(selectable, _drdw, selectable, method, dict)
	--- <exception caught here> ---
	  File "c:\python26\lib\site-packages\twisted\python\log.py", line 84, in callWithLogger
	    return callWithContext({"system": lp}, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\log.py", line 69, in callWithContext
	    return context.call({ILogContext: newCtx}, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\context.py", line 118, in callWithContext
	    return self.currentContext().callWithContext(ctx, func, *args, **kw)
	  File "c:\python26\lib\site-packages\twisted\python\context.py", line 81, in callWithContext
	    return func(*args,**kw)
	  File "c:\python26\lib\site-packages\twisted\internet\selectreactor.py", line 155, in _doReadOrWrite
	    self._disconnectSelectable(selectable, why, method=="doRead")
	  File "c:\python26\lib\site-packages\twisted\internet\posixbase.py", line 263, in _disconnectSelectable
	    selectable.connectionLost(f)
	  File "c:\python26\lib\site-packages\twisted\internet\tcp.py", line 433, in connectionLost
	    Connection.connectionLost(self, reason)
	  File "c:\python26\lib\site-packages\twisted\internet\tcp.py", line 277, in connectionLost
	    protocol.connectionLost(reason)
	  File "c:\python26\lib\site-packages\twisted\protocols\tls.py", line 460, in connectionLost
	    ProtocolWrapper.connectionLost(self, reason)
	  File "c:\python26\lib\site-packages\twisted\protocols\policies.py", line 123, in connectionLost
	    self.wrappedProtocol.connectionLost(reason)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\broker.py", line 253, in connectionLost
	    self.tub.connectionDropped(self)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\pb.py", line 1070, in connectionDropped
	    self._allConnectionsAreDisconnected.fire(self)
	  File "C:\buildbot_tahoe\FreeStorm_WinXP-x86_py2_6\build\support\Lib\site-packages\foolscap-0.6.3-py2.6.egg\foolscap\observer.py", line 42, in fire
	    assert not self._fired
	exceptions.AssertionError: 

I rebuilt the exact same version of the Tahoe-LAFS code and this time it got no error:

​https://tahoe-lafs.org/buildbot-tahoe-lafs/builders/FreeStorm%20WinXP-x86%20py2.6/builds/91

[davidsarah]

This might be related to #1768, in particular note that the traceback in 1768#comment:1 asserts at the same point (as well as triggering errors similar to the original report of #1768).

[zooko]

I think this is a duplicate of #1768.