rails 3.1 inflection problem

Question

I have a Rails 3.1 app with the following 2 models

class Listing < ActiveRecord::Base
  has_many :listing_saves
end

class Team < ActiveRecord::Base
  has_many :listing_saves
  has_many :saved_listings, through: :listing_saves, source: 'listing'
end

The Join model looks like this

class ListingSave < ActiveRecord::Base
  belongs_to :team
  belongs_to :listing
end

Mow I think that there is an inflection problem because whenever I try to run my tests I get the following error (this is an example of an error and the test that caused it)

it "should return the listing saves associated with the team" do
  save = Factory :listing_save, listing: @listing, saver: @user, team: @team
  @team.listing_saves.should include save
end

Failures:

  1) Team listing_saves associations should return the listing saves associated with the team
     Failure/Error: @team.listing_saves.should include save
     NameError:
       uninitialized constant Team::ListingSafe
     # ./spec/models/team_spec.rb:55:in `block (3 levels) in <top (required)>'

as if Rails is singularizing listing_saves into listing_safe

Here are some custom inflectors I have tried (not all at the same time) (none of them work)

# config/initializers/inflections.rb
ActiveSupport::Inflector.inflections do |inflect|
  inflect.plural 'saved_listing', 'saved_listings'
  inflect.singular 'saved_listings', 'saved_listing'
  inflect.plural 'listing_save', 'listing_saves'
  inflect.singular 'listing_saves', 'listing_save'
  inflect.singular 'listing_safes', 'listing_safe'
  inflect.plural 'listing_safe', 'listing_safes'
  inflect.irregular 'listing_save', 'listing_saves'
  inflect.irregular 'saved_listing', 'saved_listings'
end

What can I do next?

Note: I found the this similar question but the answer doesn't seem to solve my problem

Edit I followed the answer below so that I now have the following in my config/initializers/inflections.rb

ActiveSupport::Inflector.inflections do |inflect|
  inflect.irregular 'listing_save', 'listing_saves'
end

When I open up a console session and run "listing saves".singularize I get "listing_save" as I would hope. However, it seems that at least part of my application doesn't get it, my tests still fail in the same way as before. (I swear I'm restarting my server and spork before I test/run the application!).

Edit 2 I wrote some tests for inflections in my app:

describe "inflection" do
  it "should singularize listing_saves properly" do
    "listing_saves".singularize.should == "listing_save"
  end

  it "should pluralize listing_save properly" do
    "listing_save".pluralize.should == "listing_saves"
  end
end

Now I have a situation where these tests pass fine, but other tests still fail with the same error I was having before

NameError:
       uninitialized constant User::ListingSafe

Same app, same spork instance, same files loaded. Something weird is going on here!??

Answer 1

You need to define an irregular inflection:

# Test your inflections!
> "listing_save".pluralize
=> "listing_saves" # OK!
> "listing_saves".singularize
=> "listing_safe"  # Ouch :(

# Make it smarter
ActiveSupport::Inflector.inflections { |i| 
  i.irregular 'listing_save', 'listing_saves' 
}

# Test again
> "listing_saves".singularize
=> "listing_save"  # Yay!

Ruby docs:

------------------------ ActiveSupport::Inflector::Inflections#irregular
     irregular(singular, plural)
------------------------------------------------------------------------
     Specifies a new irregular that applies to both pluralization and
     singularization at the same time. This can only be used for
     strings, not regular expressions. You simply pass the irregular in
     singular and plural form.

     Examples:

       irregular 'octopus', 'octopi'
       irregular 'person', 'people'

Edit:

Some further investigation - and it looks like others have stumbled upon this same problem also (inflections not working as expected with associations). So in the meantime you can set the class name manually:

has_many :listing_saves, :class_name => "ListingSave"

Someone else with the same problem, and an additional inflections tweak. Personally I'd go with the :class_name setting instead though:

Issue with custom inflections in Ruby on Rails 3.0.3