No easy way to use a RetainPtr as a key in a HashMap using object (rather than pointer) equality

A HashMap<RetainPtr<NSObject>, ValueType> uses pointer hashing and pointer equality rather than -hash and -isEqual:.

Created attachment 188429 [details]
Patch

[Benjamin Poulain]

View in context: https://bugs.webkit.org/attachment.cgi?id=188429&action=review

> Source/WTF/wtf/RetainPtr.h:310
> +        static void constructDeletedValue(RetainPtr<P>& slot) { new (&slot) RetainPtr<P>(AdoptCF, reinterpret_cast<P *>(-1)); }
> +        static bool isDeletedValue(const RetainPtr<P>& value) { return value.get() == reinterpret_cast<P *>(-1); }

I would prefer something using an explicit constructor, like we do in RefPtr.

(In reply to comment #2)
> View in context: https://bugs.webkit.org/attachment.cgi?id=188429&action=review
> 
> > Source/WTF/wtf/RetainPtr.h:310
> > +        static void constructDeletedValue(RetainPtr<P>& slot) { new (&slot) RetainPtr<P>(AdoptCF, reinterpret_cast<P *>(-1)); }
> > +        static bool isDeletedValue(const RetainPtr<P>& value) { return value.get() == reinterpret_cast<P *>(-1); }
> 
> I would prefer something using an explicit constructor, like we do in RefPtr.

Done!

Fixed in <http://trac.webkit.org/r142924>.