Refactor Milestone.for_projects_and_groups

Refactored to use Rails 5 ActiveRecord `or` so that it can handle ids,
objects, array of objects, or relations properly.

2 files changed, 8 insertions, 7 deletions

diff --git a/app/finders/issuable_finder.rb b/app/finders/issuable_finder.rb
index a144db9fcd1..1a69ec85d18 100644
--- a/app/finders/issuable_finder.rb
+++ b/app/finders/issuable_finder.rb
@@ -155,7 +155,7 @@ class IssuableFinder
     elsif group
       [group]
     elsif current_user
-      Gitlab::GroupHierarchy.new(current_user.authorized_groups, current_user.groups).all_groups
+      Gitlab::ObjectHierarchy.new(current_user.authorized_groups, current_user.groups).all_objects
     else
       []
     end
diff --git a/app/models/milestone.rb b/app/models/milestone.rb
index 30b5884d405..7c397f3499f 100644
--- a/app/models/milestone.rb
+++ b/app/models/milestone.rb
@@ -38,13 +38,14 @@ class Milestone < ActiveRecord::Base
   scope :closed, -> { with_state(:closed) }
   scope :for_projects, -> { where(group: nil).includes(:project) }
 
-  scope :for_projects_and_groups, -> (project_ids, group_ids) do
-    conditions = []
+  scope :for_projects_and_groups, -> (projects, groups) do
+    projects = projects.compact if projects.is_a? Array
+    projects = [] if projects.nil?
 
-    conditions << arel_table[:project_id].in(project_ids) if project_ids&.compact&.any?
-    conditions << arel_table[:group_id].in(group_ids) if group_ids&.compact&.any?
+    groups = groups.compact if groups.is_a? Array
+    groups = [] if groups.nil?
 
-    where(conditions.reduce(:or))
+    where(project: projects).or(where(group: groups))
   end
 
   scope :order_by_name_asc, -> { order(Arel::Nodes::Ascending.new(arel_table[:title].lower)) }
@@ -132,7 +133,7 @@ class Milestone < ActiveRecord::Base
 
   def self.upcoming_ids(projects, groups)
     rel = unscoped
-            .for_projects_and_groups(projects&.map(&:id), groups&.map(&:id))
+            .for_projects_and_groups(projects, groups)
             .active.where('milestones.due_date > NOW()')
 
     if Gitlab::Database.postgresql?