iOS 15 SwiftUI AttributedString with Markdown doesn't render line spaces

Originator:rwgrier
Number:rdar://FB9190672 Date Originated:June 18, 2021, 10:45 AM
Status:Open Resolved:
Product:Foundation Product Version:Xcode 13 beta 1 / iOS 15 beta
Classification:Incorrect/Unexpected Behavior Reproducible:Always
 
This is using Xcode 13 beta 1 and iOS 15 beta. 

If I use an AttributedString initializer with Markdown to create a Text object in SwiftUI, any and all line spaces will be removed from the resulting view. However, if I create a Text object with markdown directly in the string, it will render the line space as expected. 

In the screenshot, the top (Hello World) line includes the AttributedString. The line breaks are not rendered at all here. The bottom line includes markdown directly in the Text initializer and renders the line break without issue. 

I've included a simple Xcode project to demonstrate this.  

Project Github Repo: https://github.com/rwgrier/feedback-FB9190672

Comments

My response to Apple

Thank you so much for getting back to me. I’ve tried this approach in Xcode 13 beta 2 without any success. I’ve included an updated Sample project. Am I still doing this wrong?

The options I am passing in are this:

AttributedString.MarkdownParsingOptions(interpretedSyntax: .inlineOnlyPreservingWhitespace)

Thank you! Ryan

By rwgrier at June 26, 2021, 12:14 a.m. (reply...)

Response from Apple

The difference in behavior you are experiencing is expected. The AttributedString(markdown:) initializer applies semantic attributes to ranges of text, it does not insert any additional characters to “render” the text. According to the CommonMark specification that we are following here, the AttributedString created with the markdown initializer does not contain newline characters and instead contains separate paragraph attributes denoting the start and end of paragraphs. On the contrary, SwiftUI’s Text view uses the MarkdownParsingOptions.InterpretedSyntax.inlineOnlyPreservingWhitespace option when parsing text input as markdown, causing all whitespace characters (including newlines) to be preserved in the output. If you were to use the .inlineOnlyPreservingWhitespace option, the whitespace in their AttributedString would be preserved in the same way that Text preserves whitespace.

By rwgrier at June 26, 2021, 12:13 a.m. (reply...)

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