Rule suggestion - Prevent using built-in prototype properties on an object

Prevent use of built-in prototype properties on an object as these won’t work on objects without a prototype, eg. object created with Object.create(null). You never know when you’ll get an object like that, so better be safe than sorry. This rule would have prevented #2688.

Should prevent the use of these:

Object.getOwnPropertyNames(Object.prototype);
//=> ["constructor", "toString", "toLocaleString", "valueOf", "hasOwnProperty", "isPrototypeOf", "propertyIsEnumerable", "__defineGetter__", "__lookupGetter__", "__defineSetter__", "__lookupSetter__", "__proto__"]

Example of misuse:

var obj = {};
obj.foo = true;
obj.hasOwnProperty('foo');
//=> true

Which will fail here:

var obj = Object.create(null);
obj.foo = true;
obj.hasOwnProperty('foo');
//=> 'Uncaught TypeError: obj.hasOwnProperty is not a function'

Instead this should be used:

var obj = Object.create(null);
obj.foo = true;
Object.prototype.hasOwnProperty.call(obj, 'foo');
//=> 'foo'

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[mysticatea]

Yes: http://eslint.org/blog/2016/05/eslint-v2.11.0-released#new-rules

[ilyavolodin]

I’ll support this. It’s a pretty important rule rule that’s hard for new users to understand without learning more about prototypical inheritance. So I think it can save people from creating a lot of errors.