intermock VS ts-to-zod

Yep, I felt the same. I'd been using the builder functions this produces for a while to at least speed up test writing but thought it should be easy to automate so went looking. Turns out there is a tool out there, Intermock, and, while fantastic, it is command line only. Our tool is built on top of that to provide a way to run it in VSCode with a couple of other niceties added.

Whenever I found myself creating another mock object for testing I kept looking at my Typescript types and thinking, can’t something look at that and do it for me? This sent me down a search for a solution and I was so stoked to find intermock which is a command line tool that does just that. While it is still a work in progress and has some limitations I have found it super helpful when writing tests.

I found Intermock a little while ago when I was looking for something similar. It looks relatively inactive, but I didn't even try it out or look into it any further.

My most recent Inception Week has helped me grow significantly as a developer as I worked on an application outside of the browser for the first time in my career. Building on the work of the awesome folks who built intermock, I adapted their tool to be used within the VSCode IDE with the extension Emulative (coming soon to a marketplace near you!). In doing so, I am hoping to do my (very) small part to improve the lives of my fellow developers by building upon the tool chain that so many others have built in order to make the work we do easier and more rewarding.

You could use something like this https://github.com/fabien0102/ts-to-zod

YES! I've introduced ts-to-zod into my codebase only yesterday, and it's served my needs exactly. It doesn't handle generics or mapped types, but that's a fair price to pay.

It also works the other way, you can define a zod schema and you can infer types for your data from it.

https://github.com/fabien0102/ts-to-zod

The closest that I know of (and I have not used this) is zod-fast-check. It generates fast-check “arbitraries” (test data generators) for property-based testing based on zod schemas. Of course, this requires that you use zod to define your types, which has some downsides. Fortunately there is another tool, ts-to-zod, (which I also have not used) which will codegen zod schemas based on TS type definitions. If you thread these four libraries together you should end up with the ability to write random tests on generated data with very little overhead. In theory.

Okay, that's an improvement! We can use TypeScript's native type syntax to define the interface, and augment it with JSDoc comments for any properties that can't be natively expressed. So, to use this with Zod, we need to convert it from the TypeScript syntax to the Zod syntax. Luckily, Fabien Bernard has spearheaded the excellent ts-to-zod project, which looks through interfaces defined in a file and outputs the equivalent Zod schemata for them.