Function isoWeekParts

packages/app-core/src/lib/template-render.ts:112–120

(date: Date)

}

function isoWeekParts(date: Date): { week: number; year: number } {
  // Shift to the Thursday of the current ISO week, working in UTC to avoid DST.
  const d = new Date(Date.UTC(date.getFullYear(), date.getMonth(), date.getDate()))
  const dayNum = d.getUTCDay() || 7 // Sunday -> 7
  d.setUTCDate(d.getUTCDate() + 4 - dayNum)
  const yearStart = new Date(Date.UTC(d.getUTCFullYear(), 0, 1))
  const week = Math.ceil(((d.getTime() - yearStart.getTime()) / 86_400_000 + 1) / 7)
  return { week, year: d.getUTCFullYear() }
}

/** ISO 8601 week number (1-53) for the given date. */
export function getISOWeek(date: Date): number {