What is the test for late filing a petition for relief from failure to file section 946.6?

The trial court agreed, primarily relying, as had plaintiff, on Lineaweaver v. Southern California Rapid Transit Dist. (1983) 139 Cal.App.3d 738. The issue in that case was whether the plaintiff had filed a petition for relief from failure to file a section 946.6 claim on time, and the court held it had not. (Id. at pp. 740-741.) In stating the facts, the appellate court noted that after the plaintiff's application for leave to file a late claim was denied, plaintiff filed his complaint before petitioning under section 946.6.