checks: warn instead of error if environment checks fail

Author: NotAShelf

src/checks.rs

@@ -2,6 +2,7 @@ use std::{cmp::Ordering, env};
 
 use color_eyre::{eyre, Result};
 use semver::Version;
+use tracing::warn;
 
 use crate::util;
 
@@ -48,12 +49,13 @@ pub fn check_nix_version() -> Result<()> {
     match current.cmp(&required) {
         Ordering::Less => {
             let binary_name = if is_lix_binary { "Lix" } else { "Nix" };
-            Err(eyre::eyre!(
-                "{} version {} is too old. Minimum required version is {}",
+            warn!(
+                "Warning: {} version {} is older than the recommended minimum version {}. You may encounter issues.",
                 binary_name,
                 version,
                 min_version
-            ))
+            );
+            Ok(())
         }
         _ => Ok(()),
     }

src/main.rs

@@ -21,22 +21,25 @@ const NH_VERSION: &str = env!("CARGO_PKG_VERSION");
 const NH_REV: Option<&str> = option_env!("NH_REV");
 
 fn main() -> Result<()> {
-    let do_warn = checks::setup_environment()?;
-
     let args = <crate::interface::Main as clap::Parser>::parse();
+
+    // Set up logging
     crate::logging::setup_logging(args.verbose)?;
     tracing::debug!("{args:#?}");
     tracing::debug!(%NH_VERSION, ?NH_REV);
 
-    if do_warn {
+    // Verify the Nix environment before running commands
+    checks::verify_nix_environment()?;
+
+    // Once we assert required Nix features, validate NH environment checks
+    // For now, this is just NH_* variables being set. More checks may be
+    // added to setup_environment in the future.
+    if checks::setup_environment()? {
         tracing::warn!(
             "nh {NH_VERSION} now uses NH_FLAKE instead of FLAKE, please modify your configuration"
         );
     }
 
-    // Verify the Nix environment before running commands
-    checks::verify_nix_environment()?;
-
     args.command.run()
 }