[Feature] Tests for types

[colbyfayock]

Feature Request

Is your feature request related to a problem? Please describe.

Like would want to consider doing this for top-level types only? this is mostly a safety measure in my mind in case build configurations somehow break type exports

Options:

• https://vitest.dev/guide/testing-types.html
• https://github.com/JoshuaKGoldberg/eslint-plugin-expect-type
• https://github.com/mmkal/expect-type
• https://github.com/TypeStrong/ts-expect
• https://github.com/tsdjs/tsd

[mrazauskas]

Please also consider TSTyche, https://github.com/tstyche/tstyche

It can test using different versions of TypeScript (tstyche --target 4.8,5.2); is lightweight (~225kB); has --watch mode; and much more (for instance, documentation website: https://tstyche.org/guide/introduction).