[bugfix] Ignore enumerable Object.prototype extensions

[ashsearle]

Several moment methods break if the Object.prototype has any additional enumerable properties.

moment().fromNow(); // "a few seconds ago"
Object.prototype.breakIt = true;
moment().fromNow(); // "Invalid date"

This is fixed by patching a few for (prop in object) loops so they only act on the object's own properties (using hasOwnProperty.)

Fixes #4802

[coveralls]

Coverage decreased (-0.007%) to 88.393% when pulling 03b5dd9 on ashsearle:fix/4802 into 0aae724 on moment:develop.

[coveralls]

Coverage decreased (-0.007%) to 88.393% when pulling 03b5dd9 on ashsearle:fix/4802 into 0aae724 on moment:develop.

[coveralls]

Coverage decreased (-0.007%) to 88.43% when pulling 21e7522 on ashsearle:fix/4802 into c1177f4 on moment:develop.

[mouse0270]

Is there any update on this pull request. It would be nice to use Object.prototype. without momentjs breaking.

[ashsearle]

@mouse0270 You can still add things to Object.prototype without breaking moment; you just need to make sure they're not enumerable. i.e. use Object.defineProperty

[ichernev]

@ashsearle thank you for the good work!