This PR is a follow-up to #8039, which provides an intuitive syntax for writing unit tests for interactive CLI commands.
The heart of this is the new `await expect(stream).toOutput(test)` custom Jest matcher, which is intended for use with the mock Client `stdout` and `stderr` stream properties. The `test` is a string that will wait for the stream to output via "data" events until a match is found, or it will timeout (after 3 seconds by default). The timeout error has nice Jest-style formatting so that you can easily identify what was output:
<img width="553" alt="Screen Shot 2022-06-29 at 10 33 06 PM" src="https://user-images.githubusercontent.com/71256/176600324-cb1ebecb-e891-42d9-bdc9-4864d3594a8c.png">
Below is an example of a unit test that was added for an interactive `vc login` session:
```typescript
it('should allow login via email', async () => {
const user = useUser();
const exitCodePromise = login(client);
// Wait for login interactive prompt
await expect(client.stderr).toOutput(`> Log in to Vercel`);
// Move down to "Email" option
client.stdin.write('\x1B[B'); // Down arrow
client.stdin.write('\x1B[B'); // Down arrow
client.stdin.write('\x1B[B'); // Down arrow
client.stdin.write('\r'); // Return key
// Wait for email input prompt
await expect(client.stderr).toOutput('> Enter your email address:');
// Write user email address into prompt
client.stdin.write(`${user.email}\n`);
// Wait for login success message
await expect(client.stderr).toOutput(
`Success! Email authentication complete for ${user.email}`
);
// Assert that the `login()` command returned 0 exit code
await expect(exitCodePromise).resolves.toEqual(0);
});
```
**Note:** as a consequence of this PR, prompts are now written to stderr instead of stdout, so this change _may_ be considered a breaking change, in which case we should tag it for major release.
* Migrate ava cli dev tests to jest
* remove outdated test
* update tests
* Update utils
* update stdio to fix stalling
* test stdio tests
* add debug logs
* more logs
* use strip ansi
* update
* add exit flag and fix next dev test
* update timeout for mac ci
* update cancel
* update cancel tests.yml -> test.yml
* update other ids -> names
* remove outdated test
* de-dupe scripts
* remove redwood dev test due to size
