export class UtilService { public static addMonths(date: Date, months: number): Date { const d = date.getDate(); date.setMonth(date.getMonth() + +months); if (date.getDate() != d) { date.setDate(0); } return date; } public static getErrorMessage(error: unknown) { if (error instanceof Error) return error.message return String(error) } public static circleSafeStringify(obj: any) { let cache: any[] = []; let str = JSON.stringify(obj, function(key, value) { if (typeof value === "object" && value !== null) { if (cache.indexOf(value) !== -1) { // Circular reference found, discard key return; } // Store value in our collection cache.push(value); } return value; }); cache = []; // reset the cache return str; } }