`FontCaps` not working?

[louistiti]

I'm trying to know whether a text is capitalized.

I found the layer.layerFrame.layerProperties.textProperties.ResourceDict.StyleSheetSet.StyleSheetData.FontCaps property but it is always set to 0.
Whereas on Photoshop, the text is correctly set to capitalized:

Is there anyone who can help to point out where I can get the correct property to see if a text is capitalized or not? 😄