console view breaks during forced builds

[exarkun]

After forcing builds simultaneously on many builders, the console view fails to render with this traceback appearing in the logs:

2010-02-13 09:15:45-0500 [Broker,0,] Peer will receive following PB traceback:
2010-02-13 09:15:45-0500 [Broker,0,] Unhandled Error
        Traceback (most recent call last):
          File "/srv/bb-master/Projects/Twisted/branches/distrib-large-write-3212/twisted/spread/banana.py", line 153, in gotItem
            self.callExpressionReceived(item)
          File "/srv/bb-master/Projects/Twisted/branches/distrib-large-write-3212/twisted/spread/banana.py", line 116, in callExpressionReceived
            self.expressionReceived(obj)
          File "/srv/bb-master/Projects/Twisted/branches/distrib-large-write-3212/twisted/spread/pb.py", line 514, in expressionReceived
            method(*sexp[1:])
          File "/srv/bb-master/Projects/Twisted/branches/distrib-large-write-3212/twisted/spread/pb.py", line 826, in proto_message
            self._recvMessage(self.localObjectForID, requestID, objectID, message, answerRequired, netArgs, netKw)
        --- <exception caught here> ---
          File "/srv/bb-master/Projects/Twisted/branches/distrib-large-write-3212/twisted/spread/pb.py", line 840, in _recvMessage
            netResult = object.remoteMessageReceived(self, message, netArgs, netKw)
          File "/srv/bb-master/Projects/Twisted/branches/distrib-large-write-3212/twisted/spread/flavors.py", line 114, in remoteMessageReceived
            state = method(*args, **kw)
          File "/srv/bb-master/Projects/Twisted/branches/distrib-large-write-3212/twisted/web/distrib.py", line 241, in remote_request
            result = res.render(request)
          File "/srv/bb-master/.local/lib/python2.5/site-packages/buildbot/status/web/base.py", line 304, in render
            data = self.content(request)
          File "/srv/bb-master/.local/lib/python2.5/site-packages/buildbot/status/web/base.py", line 387, in content
            data += self.body(request)
          File "/srv/bb-master/.local/lib/python2.5/site-packages/buildbot/status/web/console.py", line 793, in body
            debugInfo)
          File "/srv/bb-master/.local/lib/python2.5/site-packages/buildbot/status/web/console.py", line 412, in getAllBuildsForRevision
            debugInfo)
          File "/srv/bb-master/.local/lib/python2.5/site-packages/buildbot/status/web/console.py", line 332, in getBuildsForRevision
            builder.getBuild(-1), revision)
          File "/srv/bb-master/.local/lib/python2.5/site-packages/buildbot/status/web/console.py", line 342, in getChangeForBuild
            if not build.getChanges(): # Forced build
        exceptions.AttributeError: 'NoneType' object has no attribute 'getChanges'

After most of the forced builds have completed (but before all of them have), the problem goes away.

[exarkun]

The same thing happens if builds are triggered by a change source, rather than forced.

[Dustin J. Mitchell]

Don't fail if getChangeForBuild gets None for a build

I'm not sure why this would happen, but this change should prevent it from crashing. Fixes #705, hopefully.

Changeset: 71a80fdfd4ebfe28bfa4f6db04661a6e2a1bd190

[Dustin J. Mitchell]

Don't fail if getChangeForBuild gets None for a build

I'm not sure why this would happen, but this change should prevent it from crashing. Fixes #705, hopefully.

Changeset: 71a80fdfd4ebfe28bfa4f6db04661a6e2a1bd190