CI broken, due to MSRV of home crate.

[michaelkirk]

CI is currently broken, due to an MSRV bump of the home crate.

Our direct dependency proj has a transitive dependency on the which crate, which in turn depends on this home crate.

Someone recently opened harryfei/which-rs#104, which well summarizes the issue

home is not intended for external use (outside of cargo). home has cargo's automatic MSRV-3 policy, which causes build failures for downstream dependants who check against their MSRV and where the package resolver is not MSRV-aware.

They proposed a fix just yesterday: harryfei/which-rs#105

env-home is a better solution:

• it is intended for external users
• it is the proof of concept to replace env::home_dir: ACP: env::home_dir replacement rust-lang/libs-team#372
• it has a much lower MSRV
• it is MIT or Apache 2.0 licensed (like home)

As a side note, I just learned that rust 2024 intends to have an MSRV aware package resolution, yay!

We can either:

• wait to see if this fix gets merged soon
• pin to an older version of home
• abandon our 6+ month MSRV support window (not my preferred option)

All this to read a couple of env vars 😆

[urschrei]

Let's give it a few days, but I can't see a fix landing before Christmas

[michaelkirk]

#1285 was merged, which works around the problem, but I'm going to leave this issue open as a reminder that ultimately we should remove the dev-dependency specification for home.

Plausible resolutions are:

• Switch to env_home crate harryfei/which-rs#105 gets merged
• or we wait long enough that our MSRV is recent enough for home

[Xaeroxe]

which 7.0.1 is now released which should resolve this problem.

[michaelkirk]

Oh geeze, turns out bindgen removed the which crate a while back.

Sorry for the noise @Xaeroxe, but thanks for the quick response anyway.

For us, the next steps are:

• update bindgen in proj-sys: update bindgen proj#210
• release proj-sys
• update proj's proj-sys dependency
• release proj
• update geo's proj dependency
• Finally, delete our optional home dependency in geo.