support DOMException via iserror from npm

[graingert]

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[graingert]

hmm probably not worth adding this until yefremov/iserror#8

You don't need an isObject check here.

[graingert]

@benvinegar what is this isObject check for? There's no way to override what Object.prototype.toString does. without being an object. (ES2016, @@toStringTag)

[mattrobenolt]

As commented: https://github.com/joyent/node/blob/aa3b4b4/lib/util.js#L560

This was just yanked from Node core, so I'm not entirely sure what this is doing. Just standing on top of giants here.

[graingert]

yeah, it's a bit mysterious. Node has moved to a special internal isError that cannot be implemented in plain JS, because objects can override the behaviour of Object.prototype.toString via @@toStringTag

Of course legacy JS could still replace Object.prototype.toString.

[LewisJEllis]

I'd rather just add a line || toString === '[object DOMException]' to our existing isError (or refactor to a switch/case) than introduce a dependency when we don't otherwise have any.

[graingert]

@LewisJEllis you already depend on json-stringify-safe

[LewisJEllis]

No we don't, we vendored it in #883 for IE8 compat, I just forgot to remove it from package.json until #917.

[graingert]

Closing in favour on #919