1 files changed, 93 insertions, 0 deletions
diff --git a/app/finders/merge_requests/by_approvals_finder.rb b/app/finders/merge_requests/by_approvals_finder.rb
new file mode 100644
index 00000000000..e6ab1467f06
--- /dev/null
+++ b/app/finders/merge_requests/by_approvals_finder.rb
@@ -0,0 +1,93 @@
+# frozen_string_literal: true
+
+module MergeRequests
+  # Used to filter MergeRequest collections by approvers
+  class ByApprovalsFinder
+    attr_reader :usernames, :ids
+
+    # We apply a limitation to the amount of elements that can be part of the filter condition
+    MAX_FILTER_ELEMENTS = 5
+
+    # Initialize the finder
+    #
+    # @param [Array<String>] usernames
+    # @param [Array<Integers>] ids
+    def initialize(usernames, ids)
+      # rubocop:disable CodeReuse/ActiveRecord
+      @usernames = Array(usernames).map(&:to_s).uniq.take(MAX_FILTER_ELEMENTS)
+      @ids = Array(ids).uniq.take(MAX_FILTER_ELEMENTS)
+      # rubocop:enable CodeReuse/ActiveRecord
+    end
+
+    # Filter MergeRequest collections by approvers
+    #
+    # @param [ActiveRecord::Relation] items the activerecord relation
+    def execute(items)
+      if by_no_approvals?
+        without_approvals(items)
+      elsif by_any_approvals?
+        with_any_approvals(items)
+      elsif ids.present?
+        find_approved_by_ids(items)
+      elsif usernames.present?
+        find_approved_by_names(items)
+      else
+        items
+      end
+    end
+
+    private
+
+    # Is param using special condition: "None" ?
+    #
+    # @return [Boolean] whether special condition "None" is being used
+    def by_no_approvals?
+      includes_special_label?(IssuableFinder::Params::FILTER_NONE)
+    end
+
+    # Is param using special condition: "Any" ?
+    #
+    # @return [Boolean] whether special condition "Any" is being used
+    def by_any_approvals?
+      includes_special_label?(IssuableFinder::Params::FILTER_ANY)
+    end
+
+    # Check if we have the special label in ids or usernames field
+    #
+    # @param [String] label the special label
+    # @return [Boolean] whether ids or usernames includes the special label
+    def includes_special_label?(label)
+      ids.first.to_s.downcase == label || usernames.map(&:downcase).include?(label)
+    end
+
+    # Merge Requests without any approval
+    #
+    # @param [ActiveRecord::Relation] items
+    def without_approvals(items)
+      items.without_approvals
+    end
+
+    # Merge Requests with any number of approvals
+    #
+    # @param [ActiveRecord::Relation] items the activerecord relation
+    def with_any_approvals(items)
+      items.select_from_union([
+        items.with_approvals
+      ])
+    end
+
+    # Merge Requests approved by given usernames
+    #
+    # @param [ActiveRecord::Relation] items the activerecord relation
+    def find_approved_by_names(items)
+      items.approved_by_users_with_usernames(*usernames)
+    end
+
+    # Merge Requests approved by given user IDs
+    #
+    # @param [ActiveRecord::Relation] items the activerecord relation
+    def find_approved_by_ids(items)
+      items.approved_by_users_with_ids(*ids)
+    end
+  end
+end