chore: Fix tests

src/cli.rs

@@ -137,7 +137,7 @@ impl BuildConfig {
 }
 
 async fn get_current_system() -> Result<System, NixCmdError> {
-    let cmd = crate::NIXCMD.get().unwrap();
+    let cmd = crate::nixcmd().await;
     let config = NixConfig::from_nix(cmd).await?;
     Ok(config.system.value)
 }

src/config.rs

@@ -45,7 +45,7 @@ impl Config {
     /// ```
     /// along with the config.
     pub async fn from_flake_url(url: &FlakeUrl) -> Result<Config> {
-        let cmd = crate::NIXCMD.get().unwrap();
+        let cmd = crate::nixcmd().await;
         let (flake_url, attr) = url.split_attr();
         let nested_attr = attr.as_list();
         let (name, selected_subflake) = match nested_attr.as_slice() {

src/lib.rs

@@ -15,11 +15,16 @@ use tracing::instrument;
 
 static NIXCMD: OnceCell<NixCmd> = OnceCell::const_new();
 
+pub async fn nixcmd() -> &'static NixCmd {
+    NIXCMD
+        .get_or_init(|| async { NixCmd::with_flakes().await.unwrap() })
+        .await
+}
+
 /// Run nixci on the given [CliArgs], returning the built outputs in sorted order.
 #[instrument(name = "nixci", skip(args))]
 pub async fn nixci(args: CliArgs) -> anyhow::Result<Vec<DrvOut>> {
     tracing::debug!("Args: {args:?}");
-    NIXCMD.set(NixCmd::with_flakes().await?)?;
     let cfg = args.command.get_config().await?;
     match args.command {
         cli::Command::Build(build_cfg) => nixci_build(args.verbose, &build_cfg, &cfg).await,

src/nix/devour_flake.rs

@@ -37,7 +37,7 @@ pub struct DrvOut(pub String);
 pub async fn devour_flake(verbose: bool, args: Vec<String>) -> Result<DevourFlakeOutput> {
     // TODO: Use nix_rs here as well
     // In the context of doing https://github.com/srid/nixci/issues/15
-    let nix = crate::NIXCMD.get().unwrap();
+    let nix = crate::nixcmd().await;
     let mut cmd = nix.command();
     let devour_flake_url = format!("{}#default", env!("DEVOUR_FLAKE"));
     cmd.args(&[

src/nix/lock.rs

@@ -5,7 +5,7 @@ use nix_rs::flake::url::FlakeUrl;
 
 /// Make sure that the `flake.lock` file is in sync.
 pub async fn nix_flake_lock_check(url: &FlakeUrl) -> Result<()> {
-    let nix = crate::NIXCMD.get().unwrap();
+    let nix = crate::nixcmd().await;
     let mut cmd = nix.command();
     cmd.args(&["flake", "lock", "--no-update-lock-file", &url.0]);
     nix_rs::command::trace_cmd(&cmd);

src/nix/system_list.rs

@@ -53,7 +53,7 @@ async fn nix_eval_impure_expr<T>(expr: String) -> Result<T, NixCmdError>
 where
     T: Default + serde::de::DeserializeOwned,
 {
-    let nix = crate::NIXCMD.get().unwrap();
+    let nix = crate::nixcmd().await;
     let v = nix
         .run_with_args_expecting_json::<T>(&["eval", "--impure", "--json", "--expr", &expr])
         .await?;