I’m not sure how strict this project is about undefined types in general, but I found it confusing that the documentation advised to use expect(…).toBeTruthy() on a function (emitted( 'foo' )) that was typed to always return an array (i. e., always truthy).

It might be better to only add the |undefined to the overload with an event name, not to the overload that returns all events at once… not sure.

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I suppose in theory it’s a breaking change? People who previously assigned the result of .emitted() to a variable with an explicit type might now get a type error. The expected use, inline within expect(), should be fine, though.

Calls like .emitted().foo[0] or .emitted('foo')[0] may also need to be updated, depending on TypeScript config – in the tests, I’ve used the non-null assertion operator.

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