Set.filter works in Jest test

Consider this script:

const mySet = new Set([1, 2, 3]);
mySet.filter(i => i < 3);

In the browser this code throws mySet.filter is not a function error.

Yet when this code runs in a Jest test – it works.

Does somebody know why this happens and what should I do if I want my test to detect this bug?

I know how to fix the code so it does not throw. My question is how do I make the test throw and fail on this code.


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