# test

Gro integrates [`Vitest`](https://vitest.dev/) for tests:

```bash
gro test # run all tests with Gro's default `.test.` pattern
gro test thing.test somedir test/a.b # run tests matching patterns
```

> Running `gro test [...args]` calls Vitest
> inside Gro's normal [task context](/src/docs/task.md).
> Vitest has native TypeScript support and excellent performance.

Like other tasks, use `--help` to see the args info:

```bash
gro test --help
```

outputs:

```
gro test: run tests with vitest

[...args]  Array<string>  ['.test.']  file patterns to test
dir        string         '/home/desk/dev/gro/src/'       working directory for tests
```

[`gro test`](/src/lib/test.task.ts) runs all `*.test.ts`
files in your project by default using the pattern `".test."`.
So to add a new test, create a new file:

```ts
// by convention, create `src/lib/thing.ts`
// to test `src/lib/thing.test.ts`
import {test, expect} from 'vitest';

import {thing} from './thing.ts';

test('the thing', async () => {
	expect(thing).toEqual({expected: true});
});
```

See [the Vitest docs](https://vitest.dev/) for more.