Polyfill Proxy in tests to throw errors for undefined chai property assertions

[crookedneighbor]

Cha now supports throwing errors on undefined properties chaijs/chai#721

IE writing

expect(foo).to.exists;

Will fail because the property should be exist

However, it requires Proxies (available in Node 6). Until we can upgrade to Node 6, we should see if we can polyfill Proxy in tests to get this behavior.

[paglias]

Maybe https://github.com/tvcutsem/harmony-reflect

[crookedneighbor]

Looks like the PR I mentioned has been merged in, but is slated for the 4.0.0 release.

[paglias]

Waiting for 4.0 release

[lemoness]

Is this still something that needs to be done?

[paglias]

Yes, it's something that would be nice to have and it's not on hold anymore but very low priority

[lemoness]

I've updated the labels on this issue!