Remove Ubuntu from CI workflow, using only macOS for testing

[meatball133]

Due to the Ubuntu ci have a tendency to fail (this is due to a dependency which has this as known issue). It is intended to be solved with the next version which seems to be stalled atm. So I decide to disable them for now.

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[BNAndras]

Can we just use the test runner image inside the Linux CI? Otherwise, the CI is testing solutions only on macOS but the test runner is Linux. That doesn’t make a lot of sense.

[IsaacG]

Is can we use a different Linux distro? Is there some specific issue with the runner we could work around? Could we backport the fix?

[BNAndras]

If can we use a different Linux distro? Is there some specific issue with the runner we could work around? Could we backport the fix?:

The issue is with this GHA we’re using to install Swift 6.0 and 6.1: swift-actions/setup-swift#710.

[IsaacG]

Is there a prior version of that GHA that wasn't broken?

[BNAndras]

https://github.com/swift-actions/setup-swift/releases/tag/v2.2.0 predates when the GPG issue was reported in April (swift-actions/setup-swift#694). That wouldn’t support Swift 6.1 which the test runner targets unfortunately.

[BNAndras]

Since the issue seems to be getting Swift easily installed, https://hub.docker.com/_/swift/tags?name=6.1 shows several Docker images that would already have it installed.

[glennj]

Can we just use the test runner image inside the Linux CI? Otherwise, the CI is testing solutions only on macOS but the test runner is Linux. That doesn’t make a lot of sense.

8th does this. https://github.com/exercism/8th/blob/main/.github/workflows/test.yml

There is some admin work required, as there's a secret to be stored.

This also means that development cannot happen in forks (due to access to the secret): you must use branches in the central repo. This reduces the number of potential developers.

[glennj]

my 2 cents: I would suggest that, as this is "just" for CI, not the test runner, we shouldn't be too worried about the efficiency of the infrastructure. (Unless it's easy to add a docker image into a github CI workflow)

[meatball133]

Can we just use the test runner image inside the Linux CI? Otherwise, the CI is testing solutions only on macOS but the test runner is Linux. That doesn’t make a lot of sense.

Prior to the Swift 6 update which was released last month. It was only macOS testing and it worked totally fine. Also worth mentioning is that I use Linux to make the patches (and I think the other quite active contributor also do) so some Linux testing already occurs. This was mostly intended as a quick temporary fix until the library updates to fix this.