various: allow specifying profiles for platform commands

src/commands.rs

@@ -22,13 +22,17 @@ static PASSWORD_CACHE: OnceLock<Mutex<HashMap<String, SecretString>>> =
 
 fn get_cached_password(host: &str) -> Option<SecretString> {
   let cache = PASSWORD_CACHE.get_or_init(|| Mutex::new(HashMap::new()));
-  let guard = cache.lock().unwrap_or_else(|e| e.into_inner());
+  let guard = cache
+    .lock()
+    .unwrap_or_else(std::sync::PoisonError::into_inner);
   guard.get(host).cloned()
 }
 
 fn cache_password(host: &str, password: SecretString) {
   let cache = PASSWORD_CACHE.get_or_init(|| Mutex::new(HashMap::new()));
-  let mut guard = cache.lock().unwrap_or_else(|e| e.into_inner());
+  let mut guard = cache
+    .lock()
+    .unwrap_or_else(std::sync::PoisonError::into_inner);
   guard.insert(host.to_string(), password);
 }
 
@@ -449,7 +453,7 @@ impl Command {
         Some(cached_password)
       } else {
         let password =
-          inquire::Password::new(&format!("[sudo] password for {}:", host))
+          inquire::Password::new(&format!("[sudo] password for {host}:"))
             .without_confirmation()
             .prompt()
             .context("Failed to read sudo password")?;
@@ -492,11 +496,11 @@ impl Command {
       for (key, action) in &self.env_vars {
         match action {
           EnvAction::Set(value) => {
-            elev_cmd = elev_cmd.arg(format!("{}={}", key, value));
+            elev_cmd = elev_cmd.arg(format!("{key}={value}"));
           },
           EnvAction::Preserve => {
             if let Ok(value) = std::env::var(key) {
-              elev_cmd = elev_cmd.arg(format!("{}={}", key, value));
+              elev_cmd = elev_cmd.arg(format!("{key}={value}"));
             }
           },
           _ => {},

src/darwin.rs

@@ -155,8 +155,13 @@ impl DarwinRebuildArgs {
     }
 
     if matches!(variant, Switch) {
+      let profile_path = self.profile.as_ref().map_or_else(
+        || std::ffi::OsStr::new(SYSTEM_PROFILE),
+        |p| p.as_os_str(),
+      );
       Command::new("nix")
-        .args(["build", "--no-link", "--profile", SYSTEM_PROFILE])
+        .args(["build", "--no-link", "--profile"])
+        .arg(profile_path)
         .arg(&out_path)
         .elevate(Some(elevation.clone()))
         .dry(self.common.dry)

src/home.rs

@@ -99,17 +99,27 @@ impl HomeRebuildArgs {
       .run()
       .wrap_err("Failed to build Home-Manager configuration")?;
 
-    let prev_generation: Option<PathBuf> = [
-      PathBuf::from("/nix/var/nix/profiles/per-user")
-        .join(env::var("USER").map_err(|_| eyre!("Couldn't get username"))?)
-        .join("home-manager"),
-      PathBuf::from(
-        env::var("HOME").map_err(|_| eyre!("Couldn't get home directory"))?,
-      )
-      .join(".local/state/nix/profiles/home-manager"),
-    ]
-    .into_iter()
-    .find(|next| next.exists());
+    let prev_generation: Option<PathBuf> = if let Some(ref profile) =
+      self.profile
+    {
+      if profile.exists() {
+        Some(profile.clone())
+      } else {
+        None
+      }
+    } else {
+      [
+        PathBuf::from("/nix/var/nix/profiles/per-user")
+          .join(env::var("USER").map_err(|_| eyre!("Couldn't get username"))?)
+          .join("home-manager"),
+        PathBuf::from(
+          env::var("HOME").map_err(|_| eyre!("Couldn't get home directory"))?,
+        )
+        .join(".local/state/nix/profiles/home-manager"),
+      ]
+      .into_iter()
+      .find(|next| next.exists())
+    };
 
     debug!("Previous generation: {prev_generation:?}");
 

src/interface.rs

@@ -228,6 +228,10 @@ pub struct OsRebuildArgs {
   /// Build the configuration to a different host over ssh
   #[arg(long)]
   pub build_host: Option<String>,
+
+  /// Path to Nix' system profile
+  #[arg(long, short = 'P')]
+  pub profile: Option<std::path::PathBuf>,
 }
 
 impl OsRebuildArgs {
@@ -285,6 +289,10 @@ pub struct OsRollbackArgs {
   /// Whether to display a package diff
   #[arg(long, short, value_enum, default_value_t = DiffType::Auto)]
   pub diff: DiffType,
+
+  /// Path to Nix' system profile for rollback
+  #[arg(long, short = 'P')]
+  pub profile: Option<std::path::PathBuf>,
 }
 
 #[derive(Debug, Args)]
@@ -514,6 +522,10 @@ pub struct HomeRebuildArgs {
   /// Move existing files by backing up with this file extension
   #[arg(long, short = 'b')]
   pub backup_extension: Option<String>,
+
+  /// Path to Home-Manager profile
+  #[arg(long, short = 'P')]
+  pub profile: Option<std::path::PathBuf>,
 }
 
 impl HomeRebuildArgs {
@@ -623,6 +635,10 @@ pub struct DarwinRebuildArgs {
   /// Don't panic if calling nh as root
   #[arg(short = 'R', long, env = "NH_BYPASS_ROOT_CHECK")]
   pub bypass_root_check: bool,
+
+  /// Path to Darwin system profile
+  #[arg(long, short = 'P')]
+  pub profile: Option<std::path::PathBuf>,
 }
 
 impl DarwinRebuildArgs {

src/nixos.rs

@@ -330,9 +330,14 @@ impl OsRebuildArgs {
         .canonicalize()
         .context("Failed to resolve output path")?;
 
+      let system_profile_path = self.profile.as_ref().map_or_else(
+        || std::ffi::OsStr::new(SYSTEM_PROFILE),
+        |p| p.as_os_str(),
+      );
       Command::new("nix")
         .elevate(elevate.then_some(elevation.clone()))
-        .args(["build", "--no-link", "--profile", SYSTEM_PROFILE])
+        .args(["build", "--no-link", "--profile"])
+        .arg(system_profile_path)
         .arg(&canonical_out_path)
         .ssh(self.target_host.clone())
         .with_required_env()
@@ -401,7 +406,11 @@ impl OsRollbackArgs {
     info!("Rolling back to generation {}", target_generation.number);
 
     // Construct path to the generation
-    let profile_dir = Path::new(SYSTEM_PROFILE).parent().unwrap_or_else(|| {
+    let system_profile_path = self
+      .profile
+      .as_deref()
+      .unwrap_or_else(|| Path::new(SYSTEM_PROFILE));
+    let profile_dir = system_profile_path.parent().unwrap_or_else(|| {
       tracing::warn!(
         "SYSTEM_PROFILE has no parent, defaulting to /nix/var/nix/profiles"
       );
@@ -469,10 +478,14 @@ impl OsRollbackArgs {
     info!("Setting system profile...");
 
     // Instead of direct symlink operations, use a command with proper elevation
+    let system_profile_path = self
+      .profile
+      .as_deref()
+      .unwrap_or_else(|| Path::new(SYSTEM_PROFILE));
     Command::new("ln")
             .arg("-sfn") // force, symbolic link
             .arg(&generation_link)
-            .arg(SYSTEM_PROFILE)
+            .arg(system_profile_path)
             .elevate(elevate.then_some(elevation.clone()))
             .message("Setting system profile")
             .with_required_env()
@@ -534,10 +547,14 @@ impl OsRollbackArgs {
           let current_gen_link =
             profile_dir.join(format!("system-{current_gen_number}-link"));
 
+          let system_profile_path = self
+            .profile
+            .as_deref()
+            .unwrap_or_else(|| Path::new(SYSTEM_PROFILE));
           Command::new("ln")
                         .arg("-sfn") // Force, symbolic link
                         .arg(&current_gen_link)
-                        .arg(SYSTEM_PROFILE)
+                        .arg(system_profile_path)
                         .elevate(elevate.then_some(elevation))
                         .message("Rolling back system profile")
                         .with_required_env()