[iOS] Fixes right border stretching when the left side has a corner while the right side does not

[zhongwuzw]

Summary:

Fixes #46801. If the left side has a corner while the right side does not, it seems that iOS stretches the right border. Therefore, we can add 1 point to create a gap between the stretchable region and the border.

Changelog:

[IOS] [FIXED] - Fixes right border stretching when the left side has a corner while the right side does not

Test Plan:

Repro please see #46801

[zhongwuzw]

@joevilches Hi, can you help me to review this? Thanks :)

[joevilches]

@zhongwuzw Hey thanks for the ping! I chatted with @jorge-cab who is more of an expert at borders than I am, and he thinks there might be other cases that cause this and would want to look into it a bit further and try to find a different repro. Ultimately he feels we can solve this in a more general sense. I'll contact him and let him know about this PR!

[jorge-cab]

@zhongwuzw I've run into this issue before and I don't think this solution deals with every case where the issue happens, its not only with decimals on borderWidth but also with decimals on borderRadius corners and can happen on any side of a View

With your changes we still run into this with topleft and topright corners for example

I'd say we need a better understanding of why this happens so we can confidently accept a fix for this, because otherwise we might end up just covering up the issue with hacky fixes without addressing the root problem

[zhongwuzw]

@jorge-cab Thanks for your review. The bottom border stretching can also be fixed by adding 1 point. Actually, I debugged the drawing logic and did not find any issues, it seems the drawing logic is right. :)

[jorge-cab]

@zhongwuzw I think we need more thorough testing for this, since I can still find ways to trigger the bug.

I think to accept a fix we need:

• Understand what logic is causing the bug (It can be on Apple's side of things) or at least what API
• Find exactly what triggers it. Right now we only know sometimes it is triggered by decimals on either borderWidth, or borderRadius. But what specific combinations trigger it? Does the radius have to be greater than half of the width/height of the view? Maybe it has something to do with the scaling we do with overlapping radii?

I'm not a fan of adding arbitrary pixels without a deeper understanding of the issue

[react-native-bot]

This PR is stale because it has been open 180 days with no activity. Remove stale label or comment or this will be closed in 7 days.

[react-native-bot]

This PR is stale because it has been open for 180 days with no activity. It will be closed in 7 days unless you comment on it or remove the "Stale" label.

[react-native-bot]

This PR is stale because it has been open 180 days with no activity. Remove stale label or comment or this will be closed in 7 days.

[react-native-bot]

This PR was closed because it has been stalled for 7 days with no activity.