获取周数的问题

Question

在获取周数时会出现一个令人费解的现象。

请参阅随附的来源。

在步骤 0 中，可以根据 ISO8601 获得正确的星期数。
在步骤 1 中，通过更改 minimumDaysInFirstWeek，可以获得新的（正确的）周数。
在第 2 步中，如果我重新设置第一个工作日，由于某种原因，周数会恢复为原始值，即使该值没有更改。

Step2 不应该为 weekOfMonth 和 weekOfYear 返回 1 吗？

我已经用 XCode 13.4 游乐场验证了这一点。

提前致谢。

import Foundation

var calendar = Calendar(identifier: .iso8601)
let date = calendar.date(from: DateComponents(year: 2022, month: 1, day: 1))

print("*** Step 0 ***")
print("firstWeekday : \(calendar.firstWeekday)")
print("minimumDaysInFirstWeek : \(calendar.minimumDaysInFirstWeek)")
print("weekOfMonth : \(calendar.component(.weekOfMonth, from: date!))")
print("weekOfYear : \(calendar.component(.weekOfYear, from: date!))")

print("\n*** Step 1 ***")
calendar.minimumDaysInFirstWeek = 1
print("firstWeekday : \(calendar.firstWeekday)")
print("minimumDaysInFirstWeek : \(calendar.minimumDaysInFirstWeek)")
print("weekOfMonth : \(calendar.component(.weekOfMonth, from: date!))")
print("weekOfYear : \(calendar.component(.weekOfYear, from: date!))")

print("\n*** Step 2 ***")
calendar.firstWeekday = 2
print("firstWeekday : \(calendar.firstWeekday)")
print("minimumDaysInFirstWeek : \(calendar.minimumDaysInFirstWeek)")
print("weekOfMonth : \(calendar.component(.weekOfMonth, from: date!))")
print("weekOfYear : \(calendar.component(.weekOfYear, from: date!))")

结果

*** Step 0 ***
firstWeekday : 2
minimumDaysInFirstWeek : 4
weekOfMonth : 0
weekOfYear : 52

*** Step 1 ***
firstWeekday : 2
minimumDaysInFirstWeek : 1
weekOfMonth : 1
weekOfYear : 1

*** Step 2 ***
firstWeekday : 2
minimumDaysInFirstWeek : 1
weekOfMonth : 0
weekOfYear : 52