As the existing rule no-negated-in-lhs, it seems like it would be good to also disallow

if (!a instanceof b) // do something

since the developer certainly meant to write

if (!(a instanceof b)) // do something

instead. This prevents errors, and there's no legitimate case for the former that I can think of, so I think this could be enabled by default as with no-negated-in-lhs. I've thrown together a quick copy and paste job of no-negated-in-lhs which works; will attach PR.

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