[users at bb.net] StopIteration Exceptions in LineConsumerLogObserver

[Yngve N. Pettersen]

Hi,

We are using a class based on steps.ShellCommandNewStyle to process log  
output using LineConsumerLogObserver from a number of tests.

After the v2.10 upgrade (from v2.7) I have noticed several cases of  
Exceptions being thrown and being registered as such in the Build status  
information. One such case, missing handling of GeneratorExit, has been  
fixed.

But today a lot of these test runs started failing (next on todo list is  
finding out why), and was reported terminated due to an exception.

The exception turns out to be due to a StopIteration from  
LineConsumerLogObserver.headerLineReceived (at least in the case I  
investigated). My guess is that the "problem line" is one of the two last  
lines in the log, which reports the exit status of the task.

The log handler function is written like the logConsumer function in  
<http://docs.buildbot.net/current/developer/cls-logobserver.html#buildbot.process.logobserver.LineConsumerLogObserver>

Based on what I've quickly skimmed about StopIteration, it should be  
handled by the caller of the logConsumer function. This suggests that  
LineConsumerLogObserver or its caller need to be updated.


BTW, this is not new in v2.10, this exception also happened in v2.7 based  
on my grep of the log files. I guess the reason it is now showing up as an  
issue is that these exceptions are reported upwards to the step.


-- 
Sincerely,
Yngve N. Pettersen
Vivaldi Technologies AS