Hi Jaromir,

short change of my mind regarding #testTerminateInTerminate: Is this really the behavior we want? Your example is of a rather theroretical nature, but if I imagine that I would start up the termination of a process but then after some time, redecide that I do not want this, then enforcing to complete the termination sounds like an unnecessary restriction to me. Especially because in your test, the actual unwinding phase has not started yet but the process has only been suspended. That '[] ensure: ["all the logic"]' scares me a bit. :D

I think a better test could look like this: Start the terminator, terminate the terminator half-way (ideally from one of the unwind contexts), assert that the process is not yet terminated, start a second terminator, and then assert that the process has been terminated. Maybe also assert that every unwind block has been evaluated exactly one time. Based on such a test, we could use the #ensure: blocks in Process >> #terminate in a more cautious way.

What do you think of this? Or which particular scenarios were you having in mind when you wrote this test? :-)

Best,
Christoph

---
Sent from Squeak Inbox Talk

On 2021-05-29T02:34:13-05:00, m at jaromir.net wrote:

> Hi Christoph,
> 
> 
> Christoph Thiede wrote
> > Hi Jaromir,
> > 
> > thanks for writing these tests! Just a few comments here:
> > 
> > - #testTerminateInEnsure uses underscore assignments. This is a deprecated
> > syntax and apparently, in current Trunk images even disabled by default.
> > Without turning on my #allowUnderscoreAsAssignment preference, I cannot
> > even run the test in my image. Could you please convert this to modern
> > `:=` assignments?
> 
> Thanks for noticing! That's a shame ;) I must have uploaded the original
> Cuis version I was testing (Juan brought my attention to the test). I'm
> testing #terminate in parallel in both Squeak and Cuis to catch potential
> irregularities (unfortunately Pharo diverged a bit too much for an "easy"
> parallel implementation).
> 
> 
> Christoph Thiede wrote
> > - Also, there is no guarantee that in #testTerminateInEnsure, process will
> > not have completed earlier, is it? This totally depends on the speed &
> > implementation of the VM. We don't want this test to fail when running on
> > a NSA machine or on your coffee machine in 2050, do we? ;P Did you
> > consider using semaphores instead? :-)
> 
> This is the original Martin McClure's test, I didn't do any refinements yet
> but I share your concerns ;)
> 
> Christoph Thiede wrote
> > - #testTerminateInTerminate is very fancy. :D
> 
> Well, it gave me a real scare when I realized what happens when termination
> is interrupted and terminated in the middle. Fortunately the fix is so easy
> :)
> 
> Thanks very much for your comments,
> best,
> 
> > Best,
> > Christoph
> 
> 
> 
> 
> 
> 
> -----
> ^[^ Jaromir
> --
> Sent from: http://forum.world.st/Squeak-Dev-f45488.html
> 
> 
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