Cure APFS/Fstabs on Mac

[Hoverbear]

Description

Create the CreateFstabEntry action how to accept a planned CreateApfsVolume and, using that, decide if it should skip updating the fstab.

Teaches CreateFstabEntry to recognize and edit existing /nix based fstab entries to correct them.

Checklist

• Formatted with cargo fmt
• Built with nix build
• Ran flake checks with nix flake check
• Added or updated relevant tests (leave unchecked if not applicable)
• Added or updated relevant documentation (leave unchecked if not applicable)
• Linked to related issues (leave unchecked if not applicable)

Validating with install.determinate.systems

If a maintainer has added the upload to s3 label to this PR, it will become available for installation via install.determinate.systems:

curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix/pr/$PR_NUMBER | sh -s -- install

[Hoverbear]

I need to do some thorough testing on this.

[Hoverbear]

Doing this has made me want a tracing_revert_synopsis as well...

[Hoverbear]

We now report that we are about to update an entry:

However, the volume handling needs to improve:

[Hoverbear]

I'll rebase this on top #296 once it merges and it should be r4r

[cole-h]

.....this seems wrong. Am I wrong?

[Hoverbear]

YOu're right, oh my goodness. Wait, how did the tests pass?

[cole-h]

That's a great question.

We should probably make a Command wrapper that will automatically trace the commands being run locally, so we could see if this appeared in the logs...

But I think that's because the command spawned properly (so the .map_err into ActionError::command(...) never happened), but that it was just an error -- and in that case all we do is mark it uncompleted. The lack of a format! would have just made this unconditionally false (and thus always uncompleted).

[Hoverbear]

We do have this -- however it also gobbles some errors we don't necessarily want it to (such as in this case):

nix-installer/src/lib.rs

Lines 94 to 104 in f9ab680

	async fn execute_command(command: &mut Command) -> Result<Output, ActionError> {
	tracing::trace!("Executing `{:?}`", command.as_std());
	let output = command
	.output()
	.await
	.map_err(|e| ActionError::command(command, e))?;
	match output.status.success() {
	true => Ok(output),
	false => Err(ActionError::command_output(command, output)),
	}
	}

[Hoverbear]

@cole-h If you could help me know which 0o100644 you are referring to, I'd love to fix it! I don't see it anywhere in the branch.

harmonic on  hoverbear/ds-676-curable-fstabapfs-on-mac [$] is 📦 v0.4.0 via 🦀 v1.67.1 via ❄️  impure (nix-install-shell-env) 
❯ rg "0o100644"

harmonic on  hoverbear/ds-676-curable-fstabapfs-on-mac [$] is 📦 v0.4.0 via 🦀 v1.67.1 via ❄️  impure (nix-install-shell-env) 

[cole-h]

..........embarrassing. I was looking at an old commit.

You saw nothing.