Programmatic API

[sheerun]

Hello and thank you for creating this!

A programmatic API would be useful so one can use it as part of e.g. Jest or AVA test suite without running separate binary for this and allowing for easy watch mode. API could look something like:

const tsd = require('tsd')

it('has correct type definitions', async () => {
  await tsd()
})

And tsd could raise an exception if issues are found

[SamVerschueren]

Instead of throwing, it might be more useful if it returned the list of errors? Then you can verify that it has none or do something else with them?

[sheerun]

also fine

[harrysolovay]

I agree this would be very useful. Even more so if usage was possible from the tsd-executing file:

import { expectType } from "tsd";

interface Person {
  name: string;
  friends: Person[];
}

const personA = {
  name: "Joe",
  friends: [personB],
};

const personB = {
  name: "Jack",
  friends: [personA],
};

try {
  expectType<Person>(personA);
} catch(e) {}

Internally, expectType would get its parent module path (the file from which it is executed) and add it to a shared program instance. The rest of the work––it seems––is already done. This feature would be invaluable to a project on which I'm currently working. @SamVerschueren –– any chance you see this as a good addition to the API?

[SamVerschueren]

@harrysolovay Could you create a new issue so we can discuss it separately? I feel these are two separate use cases and before I decide if we should add it, I want to discuss things as to why it would be useful.

[SamVerschueren]

@sheerun Added it. Will let you know when it's released. I actually want to fix this #39 as well in the next release.

[harrysolovay]

@SamVerschueren thank you! I'm opening the new issue right now 💯

[aqzhyi]

hi, hello, @SamVerschueren

seems this issue is close/done/finish/stable (?) and already have readme wrote at master

but await tsd() got This expression is not callable. has no call signatures at 0.9.0

may you make a dist-tag on npm? 0.10.0 or 0.9.0-beta or etc?

npm info tsd

dist-tags:
beta.2: 0.6.5-beta.2  beta: 0.6.5-beta      latest: 0.9.0         next: 0.6.0-beta.5

published 3 weeks ago

[SamVerschueren]

I wanted to ship something else in the new release as well but need more time to think some things through. Will make a new release this afternoon.

[SamVerschueren]

This feature is shipped in v0.10.0 🎉