Exception within transition not raised

[nburt]

When writing tests for some after_transition callbacks I haven't seen exceptions being raised within the callback.

Example:

after_transition, :on => :finish, :do => :finish_it

def finish_it
  foo
end

I'd expect a NameError to be raised but the test continues execution. Is this intended behavior?

[rosskevin]

Take a look at the test cases like this one that halts a trasition. If you are seeking to disallow the transition on an action error, you need to use before_transition instead of after_transition.

Does this describe your desired behavior?

If you see something misbehaving or you would like it to yield more information (perhaps this case), submitting even just a test-only pull request is helpful as well.

[nburt]

I'm actually not expecting an exception to be thrown in the actual execution of the after_transition.

While writing the after_transition callback I defined a new method so I expected the test to fail with that exception raised. The test did fail, but due to some expectations at the end of my test. I thought it would have halted the after transition and the test would have failed earlier. Just led to some confusion on my part as I used Pry to figure out what was happening.

Does that make sense?

[rosskevin]

It does make sense, but I think the nature of a callback is that it will not fail for the execution code, but it certainly would be nice if it would at least dump to stderr if there was a problem. It looks like you are seeking a behavioral change wherein the after_transition would raise. I admit this has bitten me before.

I'm not sure of the reasoning or expectations on the after_transition, but I did find the related test (it was actually a misnamed file, I committed a fix on master).

You might redirect the stderr in the test and assert a message in the content, and submit a PR. Or, we could discuss a behavioral change. @seuros, do you have thoughts on the behavior of after_transition?

[obie]

Bump! I keep running into cases where server hangs if there's an error in a transition, with no indication as to what is happening. Wondering if anyone else has had these kinds of problems. When running standalone rails server it's not that big a deal, but when running in foreman, have to kill -9 the ruby process. Super annoying.

[stuxcrystal]

~~Bump! You really shouldn't do Pokemon Exception handling.~~

~~Nobody is perfect. Web-Applications can be huge. Both are not inductive to a bug-free program. If your code throws an exception because of a bug, you need to know about it in order to fix it and, preferably only to do some damage control or recover the state of the program.~~

~~If you silence the exception you signal the program, "everything went fine". Except it didn't and now you have to deal with incosistent state in your program and/or database because your code suppressed the exception that would have prevented commiting the new state to persistent storage.~~

~~This cannot be any type of intended behaviour.~~

Hmm. Does this error still persist?

[rafaelfranca]

Good question. Can you try to reproduce in the test suite?