Replace deprecated uniq on a Relation with distinct

app/models/milestone.rb

@@ -145,7 +145,7 @@ class Milestone < ActiveRecord::Base
   end
   def participants
-    User.joins(assigned_issues: :milestone).where("milestones.id = ?", id).uniq
+    User.joins(assigned_issues: :milestone).where("milestones.id = ?", id).distinct
   end
   def self.sort_by_attribute(method)

app/models/user.rb

@@ -1138,7 +1138,7 @@ class User < ActiveRecord::Base
     events = Event.select(:project_id)
       .contributions.where(author_id: self)
       .where("created_at > ?", Time.now - 1.year)
-      .uniq
+      .distinct
       .reorder(nil)
     Project.where(id: events)

app/services/delete_merged_branches_service.rb

@@ -24,8 +24,8 @@ class DeleteMergedBranchesService < BaseService
   # rubocop: disable CodeReuse/ActiveRecord
   def merge_request_branch_names
     # reorder(nil) is necessary for SELECT DISTINCT because default scope adds an ORDER BY
-    source_names = project.origin_merge_requests.opened.reorder(nil).uniq.pluck(:source_branch)
-    target_names = project.merge_requests.opened.reorder(nil).uniq.pluck(:target_branch)
+    source_names = project.origin_merge_requests.opened.reorder(nil).distinct.pluck(:source_branch)
+    target_names = project.merge_requests.opened.reorder(nil).distinct.pluck(:target_branch)
     (source_names + target_names).uniq
   end
   # rubocop: enable CodeReuse/ActiveRecord

app/services/labels/transfer_service.rb

@@ -40,7 +40,7 @@ module Labels
           group_labels_applied_to_merge_requests
         ])
         .reorder(nil)
-        .uniq
+        .distinct
     end
     # rubocop: enable CodeReuse/ActiveRecord

changelogs/unreleased/rails5-deprecated-uniq.yml

+---
+title: Replace deprecated uniq on a Relation with distinct
+merge_request: 22625
+author: Jasper Maes
+type: other

lib/gitlab/contributions_calendar.rb

@@ -73,7 +73,7 @@ module Gitlab
       # re-running the contributed projects query in each union is expensive, so
       # use IN(project_ids...) instead. It's the intersection of two users so
       # the list will be (relatively) short
-      @contributed_project_ids ||= projects.uniq.pluck(:id)
+      @contributed_project_ids ||= projects.distinct.pluck(:id)
       authed_projects = Project.where(id: @contributed_project_ids)
         .with_feature_available_for_user(feature, current_user)
         .reorder(nil)