Fix issue with trending order when user has chosen languages (#33557)

app/models/trends/links.rb

@@ -16,7 +16,7 @@ class Trends::Links < Trends::Base
   class Query < Trends::Query
     def to_arel
       scope = PreviewCard.joins(:trend).reorder(score: :desc)
-      scope = scope.merge(language_order_clause) if preferred_languages.present?
+      scope = scope.reorder(language_order_clause, score: :desc) if preferred_languages.present?
       scope = scope.merge(PreviewCardTrend.allowed) if @allowed
       scope = scope.offset(@offset) if @offset.present?
       scope = scope.limit(@limit) if @limit.present?
@@ -25,8 +25,8 @@ class Trends::Links < Trends::Base
 
     private
 
-    def language_order_clause
+    def trend_class
-      language_order_for(PreviewCardTrend)
+      PreviewCardTrend
     end
   end
 

app/models/trends/query.rb

@@ -94,11 +94,14 @@ class Trends::Query
     to_arel.to_a
   end
 
-  def language_order_for(trend_class)
+  def language_order_clause
+    Arel::Nodes::Case.new.when(language_is_preferred).then(1).else(0).desc
+  end
+
+  def language_is_preferred
     trend_class
-      .reorder(nil)
+      .arel_table[:language]
-      .in_order_of(:language, [preferred_languages], filter: false)
+      .in(preferred_languages)
-      .order(score: :desc)
   end
 
   def preferred_languages

app/models/trends/statuses.rb

@@ -15,7 +15,7 @@ class Trends::Statuses < Trends::Base
   class Query < Trends::Query
     def to_arel
       scope = Status.joins(:trend).reorder(score: :desc)
-      scope = scope.merge(language_order_clause) if preferred_languages.present?
+      scope = scope.reorder(language_order_clause, score: :desc) if preferred_languages.present?
       scope = scope.merge(StatusTrend.allowed) if @allowed
       scope = scope.not_excluded_by_account(@account).not_domain_blocked_by_account(@account) if @account.present?
       scope = scope.offset(@offset) if @offset.present?
@@ -25,8 +25,8 @@ class Trends::Statuses < Trends::Base
 
     private
 
-    def language_order_clause
+    def trend_class
-      language_order_for(StatusTrend)
+      StatusTrend
     end
   end
 

app/models/trends/tags.rb

@@ -16,7 +16,7 @@ class Trends::Tags < Trends::Base
   class Query < Trends::Query
     def to_arel
       scope = Tag.joins(:trend).reorder(score: :desc)
-      scope = scope.merge(language_order_clause) if preferred_languages.present?
+      scope = scope.reorder(language_order_clause, score: :desc) if preferred_languages.present?
       scope = scope.merge(TagTrend.allowed) if @allowed
       scope = scope.offset(@offset) if @offset.present?
       scope = scope.limit(@limit) if @limit.present?
@@ -25,8 +25,8 @@ class Trends::Tags < Trends::Base
 
     private
 
-    def language_order_clause
+    def trend_class
-      language_order_for(TagTrend)
+      TagTrend
     end
   end
 

spec/models/trends/links_spec.rb

@@ -24,6 +24,20 @@ RSpec.describe Trends::Links do
               .to eq([lower_score.preview_card, higher_score.preview_card])
           end
         end
+
+        context 'when account has chosen languages' do
+          let!(:lang_match_higher_score) { Fabricate :preview_card_trend, score: 10, language: 'is' }
+          let!(:lang_match_lower_score) { Fabricate :preview_card_trend, score: 1, language: 'da' }
+          let(:user) { Fabricate :user, chosen_languages: %w(da is) }
+          let(:account) { Fabricate :account, user: user }
+
+          before { subject.filtered_for!(account) }
+
+          it 'returns results' do
+            expect(subject.records)
+              .to eq([lang_match_higher_score.preview_card, lang_match_lower_score.preview_card, higher_score.preview_card, lower_score.preview_card])
+          end
+        end
       end
     end
   end

spec/models/trends/statuses_spec.rb

@@ -66,6 +66,20 @@ RSpec.describe Trends::Statuses do
               .to eq([lower_score.status, higher_score.status])
           end
         end
+
+        context 'when account has chosen languages' do
+          let!(:lang_match_higher_score) { Fabricate :status_trend, score: 10, language: 'is' }
+          let!(:lang_match_lower_score) { Fabricate :status_trend, score: 1, language: 'da' }
+          let(:user) { Fabricate :user, chosen_languages: %w(da is) }
+          let(:account) { Fabricate :account, user: user }
+
+          before { subject.filtered_for!(account) }
+
+          it 'returns results' do
+            expect(subject.records)
+              .to eq([lang_match_higher_score.status, lang_match_lower_score.status, higher_score.status, lower_score.status])
+          end
+        end
       end
     end
   end

spec/models/trends/tags_spec.rb

@@ -50,6 +50,20 @@ RSpec.describe Trends::Tags do
               .to eq([lower_score.tag, higher_score.tag])
           end
         end
+
+        context 'when account has chosen languages' do
+          let!(:lang_match_higher_score) { Fabricate :tag_trend, score: 10, language: 'is' }
+          let!(:lang_match_lower_score) { Fabricate :tag_trend, score: 1, language: 'da' }
+          let(:user) { Fabricate :user, chosen_languages: %w(da is) }
+          let(:account) { Fabricate :account, user: user }
+
+          before { subject.filtered_for!(account) }
+
+          it 'returns results' do
+            expect(subject.records)
+              .to eq([lang_match_higher_score.tag, lang_match_lower_score.tag, higher_score.tag, lower_score.tag])
+          end
+        end
       end
     end
   end