fix: isFunctionshouldn't be used

[anderlaw]

Code change checklist

• Verified that there is no significant performance drop (yarn mobx test:performance)

[changeset-bot]

🦋 Changeset detected

Latest commit: 8b0393e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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mobx	Patch

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[anderlaw]

I happened to see this logic:

// Exhaust primitive checks
const type = typeof a
if (!isFunction(type) && type !== "object" && typeof b != "object") return false

But isFunctionfunction uses type of inside, there is no way to pass the string of type of result into that function.

The author said it was copied from underscore, but copy wrong, here is underscore sourcecode:

// Exhaust primitive checks
var type = typeof a;
if (type !== 'function' && type !== 'object' && typeof b != 'object') return false;
return deepEq(a, b, aStack, bStack);

[urugator]

Good catch, can you please yarn changeset?

[anderlaw]

Good catch, can you please yarn changeset?

of course

[urugator]

CI got stuck again, I will close and reopen the PR to force re-run