Problem with parent-child relations in tests

[obrie]

Dennis Theisen opened this issue

1. Ok, I have a Blog which has Articles which has Comments (all ActiveRecord).

2. The StateMachine is used in the comments (for moderation/trash/spam states).

3. When running the following BlogTest, I get a strange exception (at least for me it’s strange):

   @@@ ruby
   assert Blog.create(:title => ’hey’)
   @@@

This is the exception:

@NoMethodError: undefined method `create’ for PluginAWeek::StateMachine::Event:Class
method log in event.rb at line 31
method send in association_collection.rb at line 259
method method_missing in association_collection.rb at line 259
method with_scope in base.rb at line 1841@

The statemachine isn’t used in the Blog at all, only in comments which is a second class child. I also tried to install the @plugin_test_helper@ (which is only needed for running the StateMachineTests themselves anyway, I guess)

Do you have any tip, what I am doing wrong? Or is this really a bug?

original LH ticket

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[obrie]

Dennis Theisen commented

It is also not possible for me to use
@@@ ruby
Article.create
@@@

anymore, it throws the same kind of exception:

@NoMethodError: undefined method `create’ for PluginAWeek::StateMachine::Event:Class@

I am really going crazy over this, I have no clue what I am doing wrong. But it seems, like it’s only me, as I have found no one else having this kind of problem... :(

[obrie]

Hi soleone,

Thanks for reporting the problem. It sounds like #create is getting called from within an event block like so:

@@@ ruby
state_machine do
event :do_something do
create :id => 1 # or something like that
...
end
end
@@@

Is this a problem you’re still running into or has it since been resolved?

[obrie]

Dennis Theisen commented

Hey Aaron,

unfortunately I forgot to update this ticket, because the problem is resolved.

There was a namespace clash: in our system we also had an Event class with a create() method, which was listening for Blogs and Comments creation. But somehow because the StateMachine’s Event-Class was used in one of the child classes, whenever a Blog got created, it tried to call Event.create (of our Event class), but ended up calling StateMachine::Event.create - which obviously wasn’t there.

I fixed the problem by changing the Listener in our system from Event.create to ::Event.create

Sorry for wasting your time, I thought I already updated this ticket.

Greetings, Dennis

[obrie]

Dennis Theisen commented

Btw, it seems I screwed up the layout because there is an unclosed code-tag. I tried to close it with this post :)

[obrie]

Thanks for the update. It turns out this actually is a problem which could affect other plugins here as well. I didn’t think about the fact that including PluginAWeek::StateMachine in ActiveRecord would cause all model references to Event/Machine/Transition to point to those classes under the PluginAWeek::StateMachine namespace instead of the top-level namespace. A very interesting problem!

A fix for this problem should be available within the next few days or so, at which point you should no longer need to use ::Event instead of Event :)

[obrie]

(from [a3cbd33]) Change how the base module is included to prevent namespacing conflicts [#1 state:resolved] http://github.com/pluginaweek/state_machine/commit/a3cbd3308f37deb083d277c1b253837e93e3407a