[Bye bye Spree] Bring models taxon and taxonomy from spree_core

[luisramos0]

What? Why?

Continues #4826
Here we move the following files to OFN:

• core/app/models/spree/classification.rb MERGED WITH DECORATOR
• core/app/models/spree/taxonomy.rb COPY
• spec/models/spree/taxonomy_spec.rb COPY
• core/app/models/spree/taxon.rb MERGED WITH DECORATOR
• spec/models/spree/taxon_spec.rb MERGED WITH OFN VERSION

No code changes were made, here we only move the code from spree, adapt the specs if needed and improve the code a little with rubocop and transpec.

What should we test?

We need to verify if everything related to these changes is still working. I'd run the following verifications:

• Backoffice Taxonomies feature - make sure you can manage taxonomies and taxons in them as before.
• Make sure the changes in the taxonomy are reflected in the product categories both when editing the product and also when buying it in the shopfront.
• Verify the filters by category in the shopfront are working

I am not sure what else to test related to taxonomies. Any other point we should check here?

Release notes

Changelog Category: Changed
Brought code needed in OFN from Spree so that we can make OFN independent of Spree.

[sauloperez]

There are a few easy to fix Code Climate issues. Other than that 👍

[luisramos0]

I am not sure about the "Useless assignment to variable - name"... so I dont change it.

I fixed the long lines 👍

[sauloperez]

I'm moving it to test ready because it's a fairly simple merge and it looks 👍

[filipefurtad0]

Hi @luisramos0,

Checked the following:

i) Verified previously existing Taxons were working as correctly
ii) as Superadmin, created a new Taxon/Class. Created Subclasses.
iii) as Admin - created a new products with the newly created taxons - these appear alphabetically, when editing/creating a product. Placed them on the shopfront.
iv) as User - visited the shopfront and searched for the new product (using the search field) and filtered the results using the "Filter by", using the respective newly created taxon
v) Deleting Taxons is possible, as long as they are not attributed to a product.

Not introduced by this PR:

Error observed on test case ii) but no unusual behavior was seen on the app:

https://openfoodnetwork.slack.com/archives/G010VN35QU9/p1600101520000100

Error observed on test case v) if Taxons are attributed to a product:

https://openfoodnetwork.slack.com/archives/G010VN35QU9/p1600103192000600

I could not verify issue #5252 after staging this PR, so maybe this solves it? Would that make sense? I'll comment on that issue.

This is good to go! 🎉

[filipefurtad0]

I verified #5252 now: it only affects main classes. Renaming sub-classes works both in back- and frontoffice.

[luisramos0]

Nice, thanks Filipe. We could create an issue for that JS error (last_rollback), there's some rollback logic in the JS that maybe we dont need.

re #5252 👍

[filipefurtad0]

Hey @luisramos0, thanks. Opened tech-debt #6030 concerning the removal of the rollback logic and issue #6033 on the observed errors while deleting taxons (bug-s4 I'd say).