Version in tool cache is often behind go-versions manifest's latest about setup-go

[Sergey-Murtazin]

Hi, @bdd!
Thanks for your request!

Answers to your questions:
How does /opt/hostedtoolcache get populated?
A cache of the virtual environment machine is set up by the virtual-environments team. And it isn't a "globally shared cache".

What cache gets updated by installGoVersion()?
All compilers are cached on the virtual machine image used to run your WF. For example, this is a list of all cached tools on the ubuntu-latest VM:
https://github.com/actions/virtual-environments/blob/main/images/linux/Ubuntu2004-README.md

Is checking the cache with a version spec intentional?
Yes, you are right. The "checking the cache with a version spec is intentional". It's made to reduce the go compiler installation time if the specified version matched the cached one. Or when a user doesn't specify any version and the default one is used.
If you use a fully specified version, e.g. 1.17.3, this version will be installed if there is such version in "go-versions manifest file", or on Google server.
We are considering whether to add check latest version functionality.

[brcrista]

We are considering whether to add check latest version functionality.

For more context, setup-node does this today: https://github.com/actions/setup-node/blob/d08cf222111d5c1d21b3cd4b958937f818d10d9a/docs/advanced-usage.md#check-latest-version

[dmitry-shibanov]

Hello @bdd. We released a new version and updated tag v2 with adding check-latest input. For now I'm going to close the issue. If you have any concerns feel free to ping us.