Promise (await) never resolved, tests timeout

[peschee]

Hi

I'm using AVA to test a custom server (nodejs). I'm starting the server in each test and I'd like to extract that into a function. However, when I do that, the async function never seems to resolve in the await.

Here's an example:

const startServer = async (port, cliArgs = [], execaOptions = {}) => {
  console.log('start server…');
  const subprocess = execa(SERVER_BIN_PATH, ['--port', port, SERVER_FIXTURES_DIR, ...cliArgs], execaOptions);

  // Wait for server to start before continuing
  // @see https://github.com/avajs/ava/issues/2625#issuecomment-747273810
  let connected = false;
  while (!connected) {
    connected = await isPortReachable(port, { host: 'localhost' });
  }

  // This runs…
  console.log('connected…', connected);
  return subprocess;
};

test.before(async t => {
  const subprocess = await startServer(DEFAULT_SERVER_PORT);
  // This never runs and the tests timeout…
  console.log('awaited…');

  t.context.server = subprocess;
});

if I write the before hook like this, everything works as expected:

test.before(async t => {
  const subprocess = execaNode(SERVER_BIN_PATH, ['--port', DEFAULT_SERVER_PORT, SERVER_FIXTURES_DIR]);

  // Wait for server to start before continuing
  // @see https://github.com/avajs/ava/issues/2625#issuecomment-747273810
  let connected = false;
  while (!connected) {
    connected = await isPortReachable(DEFAULT_SERVER_PORT, { host: 'localhost' });
  }

  t.context.server = subprocess;
});

Any ideas why this might be happening?

[novemberborn]

execa returns a promise for when the subprocess exits, which means await startServer() never completes.

[peschee]

You‘re right, I missed that one. Thanks!

[peschee]

@novemberborn Is there a good way to rewrite this without having to have

let connected = false;
while (!connected) {
  connected = await isPortReachable(port, { host: 'localhost' });
}

externalized?

[peschee]

This seems to work:

const startServer = async (port = DEFAULT_SERVER_PORT, cliArgs = [], execaOptions = {}) => {
  const subprocess = execaNode(SERVER_BIN_PATH, ['--port', port, SERVER_FIXTURES_DIR, ...cliArgs], execaOptions);

  let connected = false;
  while (!connected) {
    connected = await isPortReachable(port, { host: 'localhost' });
  }

  return {
    subprocess,
  };
};

and then

const { subprocess } = await startServer();