SwiftUI ZStack对齐错误

这是一个简单的代码，可产生奇怪的顶部对齐并缩小ZStack中第二个元素的文本。

BUT if you change the second text a bit (replace text2 by text2Alt1 or by text2Alt2) making it longer or shorter everything becomes correct.

这种行为的原因是什么？

struct VCardView: View {
    let text: String
    let color: UIColor

    var body: some View {
        VStack {
            Rectangle()
                .fill(Color(self.color))
                .frame(idealWidth: 800, idealHeight: 500)
                .aspectRatio(contentMode: .fit)

            Text(self.text)
        }
    }
}

struct ContentView: View {
    var body: some View {
        ZStack(alignment: .topLeading) {
            VCardView(text: text1, color: .blue)
                .frame(width: 180, height: nil)
                .alignmentGuide(.leading) { _ in 180 }
                .alignmentGuide(.top) { _ in 0 }

            //Replace text2 by text2Alt1 or text2Alt2 here:
            VCardView(text: text2, color: .green)
                .frame(width: 180, height: nil)
                .alignmentGuide(.leading) { _ in 0 }
                .alignmentGuide(.top) { _ in 0 }
        }
    }

    let text1 = "1Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec quam felis, ultricies nec, pellentesque eu, pretium quis, sem. Nulla consequat massa quis enim. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. In enim justo, rhoncus ut, imperdiet a, venenatis vitae, justo. Nullam dictum felis eu pede mollis pretium. Integer tincidu!"

    let text2 = "2Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis nat!"


    let text2Alt1 = "2Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. C"

    let text2Alt2 = "2Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Aenean commodo ligula eget dolor. Aenean massa. Cum sociis nat! Cum sociis nat!"
}

Also, you could replace Rectangle() by Image() with appropriate proportions because it was the initial state. Rectangle with the ideal size is just for demonstration.

XCode 11.5 iOS 13.5

Bug demonstration

Correct appearance