Can\'t find one under
Xcode ▶ Preferences/Text Editing ▶ \"Code Folding Ribbon\" box.
Concurring with comment by @strangetimes, I submitted to Apple Bug Reporter the following, in the new SUGGESTION format. Please feel free to pile on to Apple with your own:
35237858 : Code Folding in Xcode 9.1 Only does Entire Functions/Methods
UPDATE, A YEAR LATER…
This is fixed in Xcode 10. Code folding is back. Thanks to all those who piled on to the bug report or whatever.
The new, improved code folding in Xcode 9 or 9.1 seems to only work on an entire function or method. (I'm working in Objective-C today.) This is not very useful. You know, functions or methods are only one curly bracket deep. It is easy to eyeball them. Where I need code folding is for long control flow blocks – if, else, switch, do, while, or just loose blocks. Please bring it back so I can use code folding as it worked in Xcode 8.
The ribbon thing, although I thought it was good, others didn't – I can live without it. But code folding needs to work on all curly-bracket code blocks please.