Earlier quoted context omitted.
>The IDE should do that for you. Fail. IDE dependence is an anti-pattern and a programmer-smell.
Either the IDE/editor is able to assist you or you have to consult the documentation regularly. That's just how it is. JS' standard library, for example, is really tiny but I haven't memorized all of it. If the editor can't clue me in, I have to check the docs.
Nothing wrong with doing any of it, as long as its a dependency you can manage while also maintaining productivity... but such is the life of a Javascript developer.