This is not necessarily a bug, but something I would consider an undocumented feature. Before https://github.com/nock/nock/pull/1754/files#diff-503754c07b5098227646f913eee85885R58 it was possible to use enableNetConnect with a function, which greatly improved the flexibility of this mechanism.

As an example use case, we used to have a constantly changing Set of allowed hostnames which tests could add to. This is still possible to achieve by constructing a RegExp but it is much more awkward. There may be other use cases which cannot be converted to a RegExp at all.

What is the expected behavior?

This used to work:

const allowedOutsideHosts = [/* some hosts */];
nock.enableNetConnect({
  test: host => allowedOutsideHosts.includes(host), // or any function
});

What is the actual behavior?

You can no longer use "RegExp-like" objects (with a test function) to filter hosts for enableNetConnect(). It now defaults to a wildcard match matching anything.

Possible solutions

1. Revert back to checking for a test function?
2. Allow passing an explicit object with a test function

How to reproduce the issue

Runkit: 11.7.0
Runkit: 11.7.2

Versions

I would be willing to submit a PR for this over the next few days if you agree that it should be done. I personally think that option 2 might be the best as it would retain the proper typechecks.

Thank you!