undefined method `find_each' for []:Array

[adewinter]

Hi,

After installing the closure_tree gem (with bundler) and adding the acts_as_tree line to my model (and performing the associated migrations), I get the following error when attempting to create a node. (The model I'm attempting to use closure_tree with in this case is called Item):

> Item.create merchant_item_id: 1, name: "lol"
NoMethodError: undefined method `find_each' for []:Array
Did you mean?  find_all
from /Users/antondewinter/.rvm/gems/ruby-2.4.2/gems/closure_tree-6.6.0/lib/closure_tree/hierarchy_maintenance.rb:85:in `block in rebuild!'

merchant_item_id is a required field in the model (and I think is unrelated to this error). When I first tried to create a node, the item_hierarchies table was empty.

I tried to trace this error to a recent change in the closure_tree codebase, and I think it is related to this commit. Which sort of makes sense: when there are no children, an empty array is returned (instead of an AR association), meaning one cannot use #find_each; which would cause this error. When I modified Line 85 back to just using regular .each, there were no errors and I was able to create nodes.

Is this a bug or am I doing something wrong?

Thanks!

[mceachen]

Nice sleuthing!

I was going to suggest that it's a rails version issue with find_each, but that seems to be fairly stable since v3.0. Here's the PR associated with that diff.

It might be safer to apply either find_each or each, based on which method exists on the children collection--i.e., the collection is a static array, then call each, if the collection is active_record magicks, call find_each.

If you think that sounds sane, I'm more than happy to take a PR (especially if it has a breaking test!)

[adewinter]

I made a mistake. It turns out there was code in my codebase that overrode the #children method, causing these issues. Once I removed that bit of code, there were none of the errors I described above. Sorry for leading you on a goose chase!

I'm going to go ahead and close this ticket.

[nbekirov]

I was just looking into this and was about to post that it's not reproducible on Rails 5.1.4... 😃