Fixed an issue: ko.isWriteableObservable incorrectly returns false for computed observables in the mapping context.

[fsoikin]

The withProxyDependentObservable function replaces ko.dependentObservable, but does not replace ko.isWriteableObservable, which causes the latter to always return false for computeds.
At the same time, the mapping plugin itself uses isWriteableObservable a lot in the mapping process to determine whether it should use the existing observable or replace it with a new, writeable one. Since all computeds look like non-writeable at this point, the mapping procedure will replace all computeds with new observables, thus screwing up the viewmodel inner mechanics.

The solution is simple: when replacing ko.dependentObservable with a proxy, also replace ko.isWriteableObservable.

[simeyla]

This doesn't work - you get infinite recursion

Should be
var isWriteable = localIWO(o);

instead of
var isWriteable = ko.isWriteableObservable(o);

(inside the ko.isWriteableObservable function)

[fsoikin]

Indeed.
But this request is so old, and I'm not even sure it's into the right repository anymore.
Is anybody even interested in this?
I've stopped using ko.mapping a long time ago.

[simeyla]

It's a shame the mapping seems to have been neglected - it definitely has some issues and I wish it had been maintained - but I'm stuck with using it for now :-)

The reason I needed this change was I'd created a simple writeable observable to auto-convert a string or date to a proper Date object and I wanted it to work with the mapper. Making the change I suggested is working just fine.

[fsoikin]

Well, glad to be of help. Good luck.