provision macos test runner with case sensitive filesystem

[devsnek]

its not unheard of for people to use case sensitive, and its getting more popular with the new apfs

motivation: nodejs/node#20954

[maclover7]

@devsnek Do you know what extra configuration option(s) would be needed to make the FS be case sensitive?

[devsnek]

@maclover7 i just know that case sensitivity is an option when formatting drives to APFS (and HFS+) which is presented in disk utility and during os upgrades in the UI. i don't know how that would plug into the build infra

[gibfahn]

@devsnek Do you know what extra configuration option(s) would be needed to make the FS be case sensitive?

AFAIK you need to reformat the partition from HFS Case Insensitive to HFS Case Sensitive (or the APFS equivalent, but I don't think our Macs are on APFS yet).

[mhdawson]

@gdams, can you figure out what would need to change in our ansible template to enable Case Sensitivity? We might want a variant that we can use to install 1 or more Case Sensitive instances.

[gdams]

@mhdawson this doesn't seem like the sort of thing that we could configure using ansible. Switching between HFS Case Insensitive and HFS Case Sensitive requires a complete OS reinstall which ansible wouldn't be able to handle as it requires SSH amongst many other things. I agree that it would make sense to have a mac configured in the farm that is HFS Case Sensitive but this would have to be an initial step during OS installation rather than in ansible.

[gibfahn]

@gdams while I agree it's not really something we want to manage with Ansible (and should be done on OS install instead), I guess it should technically be possible to reformat the disk, probably by partitioning the current disk, reformatting the partition, then copying everything over. It sounds a bit painful though.

Reformatting the disk you're currently running on sounds a bit dicey.

[devsnek]

you could just create one of those dynamically growing volumes formatted to case sensitive

[mhdawson]

I don't think we want to stand on our head to do it with ansible if it does not make sense. I like the idea from @devsnek where we create a new volume that is formatted appropriately, but if that is too hard through ansible then just creating instructions for the initial OS install probably makes sense.

[sam-github]

Closing as part of an OS X issue cleanup.

1. There has been no progress on this for 1.5 years
2. The motivating issue test: fix fs realpath.native test node#20954 appears to be a one-off, there have not been followon issues, either because the code is robust to case-sensitivity on OS X, or because so few are using those OS X install options that no one cares.
3. Running an entire set of 3 new test machines on our strained OS X architecture, especially ones that require custom FS formatting, strikes me as not worthwhile for such a fringe (and unrepeated) problem.

Closing for now, but if I'm wrong and someone is keen to try to provision a set of machines to address this, it can be reopened.

ATM, we don't have sufficient hardware resources to do this, though, not AFAICT.