The following command: breakpoint modify 1 -c "(BOOL)[$rdi isKindOfClass:[NSTextView class]]" always stops execution, even when not clicking on anything.
Just switching to the Xcode window will stop execution and I cannot get to the NSTextViewSubClass
Xcode 8.3.2
What is the output of the lldb console?
What I did was to
(lldb) continue
Util I could hit the code area, then I did this. 
I hope this helps.
The hitTest: now gets called even when you hover your mouse over a NSView in Xcode. To get around this, you can have Terminal be the main responder then cmd + click on Xcode while it’s behind the Terminal window.