Make Admin::UsersController work with Ruby 2.6

Ruby 2.6 introduced `Enumerable#filter`, which takes no arguments.
Attempting to call `filter` on an `ActiveRecord::Relation` with a scope
will fail with a `wrong number of arguments (given 1, expected 0)`
message because the `Enumerable#filter` implementation overrides the
delegated `ActiveRecord::Relation#filter` method.

To make Admin::UsersController compatible with Ruby 2.6, rename
`User.filter` to `User.filter_items`.

1 files changed, 14 insertions, 0 deletions

diff --git a/spec/controllers/admin/users_controller_spec.rb b/spec/controllers/admin/users_controller_spec.rb
index c934db9e237..cb24a6ef142 100644
--- a/spec/controllers/admin/users_controller_spec.rb
+++ b/spec/controllers/admin/users_controller_spec.rb
@@ -8,6 +8,20 @@ describe Admin::UsersController do
     sign_in(admin)
   end
 
+  describe 'GET #index' do
+    it 'retrieves all users' do
+      get :index
+
+      expect(assigns(:users)).to match_array([user, admin])
+    end
+
+    it 'filters by admins' do
+      get :index, params: { filter: 'admins' }
+
+      expect(assigns(:users)).to eq([admin])
+    end
+  end
+
   describe 'GET :id' do
     it 'finds a user case-insensitively' do
       user = create(:user, username: 'CaseSensitive')