Minor macOS code fixups (#1346)

* CreateNixVolume: use constant for darwin-store service label

* BootstrapLaunchctlService: remove exit code 37 check

This is returned with the message "Operation already in progress".
However, `print` doesn't actually start anything, so I highly doubt this
can ever trigger. This has existed since the beginning of this file, but
I believe it's a relic of some leftover testing with `launchctl load` /
`launchctl unload` / `launchctl bootstrap` / `launchctl bootout`, which
likely could return this.

Author: cole-h

src/action/macos/bootstrap_launchctl_service.rs

@@ -41,7 +41,7 @@ impl BootstrapLaunchctlService {
                 .await
                 .map_err(|e| Self::error(ActionErrorKind::command(&command, e)))?;
             // We presume that success means it's found
-            command_output.status.success() || command_output.status.code() == Some(37)
+            command_output.status.success()
         };
 
         let is_disabled = service_is_disabled(DARWIN_LAUNCHD_DOMAIN, &service)

src/action/macos/create_nix_volume.rs

@@ -19,6 +19,7 @@ use super::{
 };
 
 pub const NIX_VOLUME_MOUNTD_DEST: &str = "/Library/LaunchDaemons/org.nixos.darwin-store.plist";
+pub const NIX_VOLUME_MOUNTD_NAME: &str = "org.nixos.darwin-store";
 
 /// Create an APFS volume
 #[derive(Debug, serde::Deserialize, serde::Serialize, Clone)]
@@ -88,7 +89,7 @@ impl CreateNixVolume {
 
         let setup_volume_daemon = CreateVolumeService::plan(
             NIX_VOLUME_MOUNTD_DEST,
-            "org.nixos.darwin-store",
+            NIX_VOLUME_MOUNTD_NAME,
             name.clone(),
             "/nix",
             encrypt,
@@ -97,11 +98,11 @@ impl CreateNixVolume {
         .map_err(Self::error)?;
 
         let bootstrap_volume =
-            BootstrapLaunchctlService::plan("org.nixos.darwin-store", NIX_VOLUME_MOUNTD_DEST)
+            BootstrapLaunchctlService::plan(NIX_VOLUME_MOUNTD_NAME, NIX_VOLUME_MOUNTD_DEST)
                 .await
                 .map_err(Self::error)?;
         let kickstart_launchctl_service =
-            KickstartLaunchctlService::plan(DARWIN_LAUNCHD_DOMAIN, "org.nixos.darwin-store")
+            KickstartLaunchctlService::plan(DARWIN_LAUNCHD_DOMAIN, NIX_VOLUME_MOUNTD_NAME)
                 .await
                 .map_err(Self::error)?;
         let enable_ownership = EnableOwnership::plan("/nix").await.map_err(Self::error)?;