Minor: mocha never finishes because it no longer receives the --exit option

[joeytwiddle]

Description / Steps to reproduce / Feature proposal

1. On a default project, add some annoying code:

   echo "setInterval(() => console.log('nasty loop'), 60000);" \
       >> src/controllers/ping.controller.ts

2. Run npm test

Current Behavior

After the tests have passed, mocha blocks. The process never ends.

Expected Behavior

After the tests have passed, mocha should exit back to the command-line.

Additional

I guess that --exit is the desired behaviour, because I see it in packages/build/config/mocha.opts.

But it doesn't appear in generators/project/templates/test/mocha.opts (if it did then I guess that would close the issue).

The change happened somewhere between version 1.0.0 and 1.0.1 of @loopback/build

git diff @loopback/build@1.0.0 @loopback/build@1.0.1 packages/build

It looks like the new behaviour is to only use the default mocha.opts if there is no test/mocha.opts in the project.

Whether --exit is really desirable is up to you! But I feel the "default fallback" opts should be closer to the "template default".

Workaround for consumers

When I encountered this problem, I simply added --exit to our project's test/mocha.opts to fix it.

Another workaround might be to find and destroy whatever is keeping the mocha process alive. You may use why-is-node-running to help with that.

Acceptance criteria

• [ ] Add "exit": true to default Mocha options in scaffolded projects - see packages/cli/generators/project/templates/.mocharc.json

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[bajtos]

Thank you @joeytwiddle for reporting the problem! I vaguely remember that some of LB connectors may be keeping the process running because of the connection pool they use in background (and don't unref it as they should).

I think it will be best to add --exit to the mocha opts file template we use for new projects. Would you like to contribute this change?

@strongloop/loopback-maintainers any objections or other proposals?

[simlt]

Hi, I am currently having a similar problem on a loopback project when using the mssql connector, so I wanted to contribute. I can confirm that enabling the exit option for mocha solved the problem.

I'm leaving a comment just to let others know that I want to take care of this issue.

[dhmlau]

Thanks @simlt. Let me assign it to you.

[bajtos]

closing as done via #6475