form.setFieldValue based on previous value

[twiddler]

Hey everyone! 👋

I would like to set the value of a field foo based on the value it currently has. This is currently possible by using

form.setValues(prev => ({ foo: prev.foo + 1 }))

but (to the best of my knowledge) not by something like

form.setFieldValue("foo", prev => prev + 1)

I thought I'd give it a shot to make this a proper pull request, but I am facing type issues in the test I added:

Parameter 'prev' implicitly has an 'any' type. ts(7006)

I would really appreciate if someone could take it from here. Thanks! 🙏

[rtivital]

Please fix test errors

[twiddler]

I ran npm run prettier:write to fix the prettier errors. The type error that now shows is the one that I do not know how to solve. I'd appreciate any help. 🙏

[twiddler]

Thanks @Pr0gramWizard! 🙏

[rtivital]

Thanks!