jre_minimal: add basic test

[raboof]

Motivation for this change

Adds a very basic test for jre_minimal.

This is a rather crude starting point, I'd welcome feedback!

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[roberth]

This is a good starting point for testing the correctness of jre_minimal. And I'd be happy to merge it.

Perhaps this is the wrong place to ask, but what about its validity? I couldn't find a use for jre_minimal. For instance, openapi-generator-cli needed some xml-related module.

If we don't have a practical application for jre_minimal, this is still a useful smoke test for Nixpkgs' jlink glue. In that case we should make the purpose clear though.

[raboof]

This is a good starting point for testing the correctness of jre_minimal. And I'd be happy to merge it.

Perhaps this is the wrong place to ask, but what about its validity? I couldn't find a use for jre_minimal. For instance, openapi-generator-cli needed some xml-related module.

If we don't have a practical application for jre_minimal, this is still a useful smoke test for Nixpkgs' jlink glue. In that case we should make the purpose clear though.

Indeed I think it should not be used inside of nixpkgs itself, but be available for easy access to the 'jlink glue' for more "closed-world" downstream projects. I've added a test showing that off and amended it to this PR.

[roberth]

Aha! It didn't occur to me that you could override the set of modules. It's documented in the manual though, so 👍 .

More than enough reason to include these tests. Just one nitpick and this is good to go.

[roberth]

Thanks!