Following a discussion about the topic of venv activation scripts:

I think someone just needs to validate and pull in those upstream changes [from virtualenv package] into our virtual environment activation scripts. Ideally, we'd have some test coverage that makes it apparent we're resolving the problem.

-- originally from #14917 (comment)

Then in #15272:

What are the requirements of the requested test(s)? I added a nushell activation test. Do you want more tests for all other supported shell(s)? I'm of the impression that nushell needed a test to detect breakages because nushell is still in v0.x. I have only ever used bash and pwsh (with much reluctance).

It'd be ideal to have test coverage for them all, but I don't think it's necessary to do here! Especially if you're reluctant :) We can open an issue to track it.

Let this be the issue to track adding integration/unit tests for activating venv in variously supported shells.

Proposed idea

An aggregated discussion between zanieb and myself across the aforementioned threads:

I see now that integration tests are written directly in the CI.yml workflow (an overwhelmingly long file). While unconventional per rust standards, this makes writing integration tests easier.

we could do another testing strategy within our test suite, e.g., we'd add a new test-nushell feature then assume nushell is available and add a snapshot test for the activation script that's gated by the feature. Then, we'd install nushell in the Linux cargo test run.