Monospaced system font replaced by Times New Roman in iOS 13+

[jeffjfk]

Hello there,
First of all, thanks a lot for this library, soooo usefull :)

I'm using it in my iOS app and it works very well, even with custom fonts!

But I think I found a bug when using a monospaced system font, running on iOS 13:
in some cases, I need to use UIFont.monospacedDigitSystemFont(ofSize: 30, weight: .bold).
So, instead of using a custom font, I use a system one.
Oddly, this causes my label to be displayed with Times New Roman while I'm not using this font at all.

I found this radar which could explain what's going on: https://openradar.appspot.com/6153065

Back in the code, looking for the what line is responsible of this change...
Here is my code to set each needed styles:

let md = KwitMarkdown(string: myText)
md.setFontColorForAllStyles(with: myColor)
md.setFontSizeForAllStyles(with: myFont.pointSize)
md.setFontNameForAllStyles(with: myFont.fontName)
			
let boldFont      = kwitEmphasizedFont
md.bold.fontName  = myBoldFont.fontName
md.bold.fontSize  = myBoldFont.pointSize
md.bold.color     = myBoldColor ?? myColor

It works well for every texts in a custom font (I'm using Gilroy in my app) except for those with a system one.
It appears the font change occurs in the file SwiftyMarkdown+iOS.swift.

func font( for line : SwiftyLine, characterOverride : CharacterStyle? = nil ) -> UIFont {

//before this condition, 
//font == <UICTFont: 0x7f9dbd61fc10> font-family: "UICTFontTextStyleBody"; font-weight: normal; font-style: normal; font-size: 17.00pt
//finalSize == 30.0
//textStyle == UICTFontTextStyleBody
//existentFontName == ".SFUI-Bold"
//It seems OK

    if let customFont = UIFont(name: existentFontName, size: finalSize)  {
        //but starting here, 
        //customFont == <UICTFont: 0x7f9dbb4bf650> font-family: "Times New Roman"; font-weight: normal; font-style: normal; font-size: 30.00pt
        ...
    }
...

Looking at this WWWDC2019 video, at 2'45 it is said we should no more try to get a UIFont by it's name : https://developer.apple.com/videos/play/wwdc2019/227/

Has anyone any idead how to solve that?

[erychagov]

I made some workaround, hope it will be helpfully:

let markdown = SwiftyMarkdown(string: text)
let mutableAttributedText = NSMutableAttributedString(attributedString:  markdown.attributedString())
mutableAttributedText.enumerateAttributes(
    in: NSRange(location: 0, length: mutableAttributedText.length),
    options: NSAttributedString.EnumerationOptions.reverse
) { (attrs, range, _) in
    guard attrs.keys.contains(NSAttributedString.Key.font) else {
        return
    }
    mutableAttributedText.removeAttribute(NSAttributedString.Key.font, range: range)
    mutableAttributedText.addAttribute(NSAttributedString.Key.font, value: font, range: range)
}

The idea is just to replace all font attributes by your font