Typescript, unit testing
How can i make a unit tests for my middleware ? I'm using Jest.

```typescript
export const checkUUID: Application.Middleware<State, Context> = async (
  context,
  next
) => {
  const uuid = new RegExp(
    /^[0-9A-F]{8}-[0-9A-F]{4}-[0-9A-F]{4}-[0-9A-F]{4}-[0-9A-F]{12}$/i
  )
  if (context.query.id && context.query.id.match(uuid)) {
    await next()
  } else {
    context.status = 403
  }
}
```

```typescript
export const parseBody: Application.Middleware<State, Context> = async (
  context,
  next
) => {
  const body = await coBody.json(context.req, { limit: '1mb' })

  if (body) {
    context.update = body
    await next()
  } else {
    context.status = 418
  }
}
```

```typescript
const app = new Application<State>()

app.use(checkUUID)
app.use(parseBody)
app.use(context => {
  if (!context.headerSent) {
    context.body = 'OK'
  }
})

export { app }
```
