info in oj.copyProperty is undefined

[Zemke]

The info variable in the oj.copyProperty method is occasionally undefined causing the whole app to stop.

I worked around it this way:

oj.copyProperty = function(dest, source, propName) {
        var info;
        info = Object.getOwnPropertyDescriptor(source, propName);
        if (info === undefined) {
            info = {
                value: [],
                enumerable: false,
                writable: false,
                configurable: true
            };
        }

        if (info.value != null) {
            info.value = _clone(info.value);
        }
        return Object.defineProperty(dest, propName, info);
    };

https://github.com/ojjs/oj/blob/master/src/oj.js#L344

[evanmoran]

Thanks for writing this. I honestly didn't think getOwnPropertyDescriptor could fail. Good catch, and I'll be sure to put it in the next release.

[evanmoran]

@Zemke Did you have a repro for this? It appears getOwnPropertyDescriptor doesn't walk the prototype chain.. Is that where you are running into this? Trying to decide if it is worth creating a recursive helper for getOwnPropertyDescriptor and if empty array, [], is the best default.

[Zemke]

I have no public repository for this. I don't know if the issue had anything to do with the prototype chain. If you want I will reproduce this and get you more information.

[evanmoran]

@Zemke If you can repro it that would be greatly appreciated=). I'm mostly trying to write a unit test and wondering where the issue is coming from; copyProperty is used in oj.createType's inheritance mechanism, so maybe there are special cases to inheritance I'm missing. I definitely agree some sort of defaulting is needed here.

Secondly, I'm wondering why you chose value: [].

[Zemke]

I will reproduce it. Expect an answer on the weekend.

I chose value: [] because I had seen it was assigned that every now and then when Object.getOwnPropertyDescriptor wasn't returning undefined. Moreover it just worked.

[evanmoran]

Thanks man. I'll probably submit your fix in 0.2.2 just so no one else runs into this in the mean time. If you repro it I'll add a unit test and maybe adjust the fix depending on what is causing it.

[Zemke]

Hmm... can't figure out the problem. I can't jump into the function. It returns undefined on its fourth call when propName is "after".

[evanmoran]

I added your fix in v0.2.2. Let me know if it works for you!

[Zemke]

Great! I will report back soon.