Created scopes to hold reusable queries

Extracted queries from the finder, and added as scopes in merge-requests
model

ee/app/finders/merge_requests/by_approvals_finder.rb

@@ -42,37 +42,24 @@ module MergeRequests
 
     # Merge Requests without any approval
     def without_approvals(items)
-      items
-        .left_outer_joins(:approvals)
-        .joins('LEFT OUTER JOIN approvals ON approvals.merge_request_id = merge_requests.id')
-        .where(approvals: { id: nil })
+      items.without_approvals
     end
 
     # Merge Requests with any number of approvals
     def with_any_approvals(items)
       items.select_from_union([
-        items.joins(:approvals),
-        items.joins('INNER JOIN approvals ON approvals.merge_request_id = merge_requests.id')
+        items.with_approvals
       ])
     end
 
     # Merge Requests approved by given usernames
     def find_approved_by_names(items)
-      find_approved_by_query(items, :username, usernames)
+      items.approved_by_users_with_usernames(usernames)
     end
 
     # Merge Requests approved by given user IDs
     def find_approved_by_ids(items)
-      find_approved_by_query(items, :id, ids)
-    end
-
-    def find_approved_by_query(items, field, values)
-      items
-        .joins(:approvals)
-        .joins(approvals: [:user])
-        .where(users: { field => values })
-        .group('merge_requests.id')
-        .having("COUNT(users.id) = ?", values.size)
+      items.approved_by_users_with_ids(ids)
     end
   end
 end

ee/app/models/approval.rb

@@ -6,4 +6,6 @@ class Approval < ApplicationRecord
 
   validates :merge_request_id, presence: true
   validates :user_id, presence: true, uniqueness: { scope: [:merge_request_id] }
+
+  scope :with_user, -> { joins(:user) }
 end

ee/app/models/ee/merge_request.rb

@@ -41,6 +41,23 @@ module EE
       delegate :sha, to: :base_pipeline, prefix: :base_pipeline, allow_nil: true
       delegate :merge_requests_author_approval?, to: :target_project, allow_nil: true
 
+      scope :without_approvals, -> { left_outer_joins(:approvals).where(approvals: { id: nil }) }
+      scope :with_approvals, -> { joins(:approvals) }
+      scope :approved_by_users_with_ids, -> (user_ids) do
+        with_approvals
+          .merge(Approval.with_user)
+          .where(users: { id: user_ids })
+          .group(:id)
+          .having("COUNT(users.id) = ?", user_ids.size)
+      end
+      scope :approved_by_users_with_usernames, -> (usernames) do
+        with_approvals
+          .merge(Approval.with_user)
+          .where(users: { username: usernames })
+          .group(:id)
+          .having("COUNT(users.id) = ?", usernames.size)
+      end
+
       participant :participant_approvers
 
       accepts_nested_attributes_for :approval_rules, allow_destroy: true

ee/lib/ee/api/merge_requests.rb

@@ -19,7 +19,7 @@ module EE
             optional :approver_ids, types: [String, Array], array_none_any: true,
                      desc: 'Return merge requests which have specified the users with the given IDs as an individual approver'
             optional :approved_by_ids, types: [String, Array], array_none_any: true,
-                     desc: 'Return merge requests which have been approved by the specified the users with the given IDs'
+                     desc: 'Return merge requests which have been approved by the specified users with the given IDs'
           end
         end
       end