Re: Linux/Clang/Libobjc2 failure part 2 (ng)

[David Chisnall]

Hi Fred,

Sorry for the late reply:

On 1 Jul 2018, at 22:39, Fred Kiefer <fredkiefer@gmx.de> wrote:
> 
> I finally got around to tests this and commented out most of the subclass 
> methods in GSString (apart from the length and characterAtIndex: and a few 
> that where raising an exception in an intermediate class, plus one 
> deprecated, which gets delegated from the abstract class to the concrete 
> one). Even with all these missing the test, extended with our additional test 
> code, worked correctly on my machine. Maybe you could give me an additional 
> hint where you see the unicode bugs?

I found that there was some inconsistent handling of 
-rangeOfComposedCharacterSequenceAtIndex: between NSString and GSString that 
were causing failures when the NSConstantString implementation was using the 
NSString version.  Looking at the code in the newabi branch of -base, where I 
was experimenting with using ICU for this, I think that’s the thing that was at 
the root of all of the test failures that I was seeing.

This method is slightly complicated by the fact that Cocoa and the unicode 
standard disagree on whether CR LF is a single composed character (Cocoa says 
no, unicode says yes).  

David