[jakelazaroff]

How would that catch a misspelled prop name?

[mikewhy]

You would end up defining PropTypes, and ESLint is capable of keeping you in check there.

It's much worse than just using TypeScript (only at runtime, PropTypes aren't that useful anywhere else, PropType syntax doesn't match Flow, TS, or jsdoc, ESLint can't check any PropTypes you spread in), but it can get you by in a pinch.

[ngerrity]

linting wouldn't, but if you're writing unit tests, that kind of problem would be caught pretty quickly.

[mikewhy]

This also works in TypeScript's favor. Meaning you can skip writing tests that simply check you're giving the correct props.

[nailer]

I don't think anyone /does/ write tests that simply check they're giving the correct props. They write unit tests, and props are part of that.

[eyelidlessness]

This also works in TypeScript's favor. You get test coverage which you would never write. A "simple" component that doesn't have any logic and doesn't warrant a test still checks its prop types, and you don't have to do anything other than make the compiler pass.