1 files changed, 34 insertions, 0 deletions
diff --git a/app/services/branches/delete_merged_service.rb b/app/services/branches/delete_merged_service.rb
new file mode 100644
index 00000000000..9fd5964bf94
--- /dev/null
+++ b/app/services/branches/delete_merged_service.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+module Branches
+  class DeleteMergedService < BaseService
+    def async_execute
+      DeleteMergedBranchesWorker.perform_async(project.id, current_user.id)
+    end
+
+    def execute
+      raise Gitlab::Access::AccessDeniedError unless can?(current_user, :push_code, project)
+
+      branches = project.repository.merged_branch_names
+      # Prevent deletion of branches relevant to open merge requests
+      branches -= merge_request_branch_names
+      # Prevent deletion of protected branches
+      branches = branches.reject { |branch| ProtectedBranch.protected?(project, branch) }
+
+      branches.each do |branch|
+        ::Branches::DeleteService.new(project, current_user).execute(branch)
+      end
+    end
+
+    private
+
+    # 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).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
+  end
+end