Clarify OCaml version constraint

[talex5]

ocaml-base-compiler is version 5.0.0~alpha1 but ocaml itself is just 5.0.0.

(spotted by @kit-ty-kate in ocaml/opam-repository#21935)

[kit-ty-kate]

could you also add the "@runtest" {with-test & os != "macos"} for eio-main too?

[talex5]

could you also add the "@runtest" {with-test & os != "macos"} for eio-main too?

I don't think so. That bit is generated by dune.

[kit-ty-kate]

you can always stop generating the opam file by dune. It’s fairly useless and more bothersome than anything once first generated IMO

[talex5]

It would be better to disable just the network tests. I can disable them on macos (I think) by changing the dune file to:

(mdx
  (package eio_main)
  (packages eio_main)
  (files (:standard \ "network.md")))

(mdx
  (package eio_main)
  (packages eio_main)
  (enabled_if (<> %{system} "macos"))
  (files "network.md"))

However, that disables the tests even outside of the opam sandbox, which isn't what we want.

A better option might be to add a way to skip blocks in MDX if some condition is met. Then we could e.g. skip the IPv6 tests if binding to ::1 raises an exception.

[talex5]

Merging this part for now. I've opened #275 to track the test problem.