feat: Show error if no clusters are found in repo

src/main.rs

@@ -6,15 +6,26 @@ use crete::cluster::get_clusters;
 use crete::environment::PathEnvironment;
 use crete::set_repo_path;
 use minijinja::context;
+use thiserror::Error;
 
 use crate::cli::{Cli, Commands, GlobalOpts};
 
-fn generate(opts: &GlobalOpts) {
+#[derive(Debug, Error)]
+enum Error {
+    #[error("No clusters where found")]
+    NoClustersFound,
+}
+
+fn generate(opts: &GlobalOpts) -> Result<(), Error> {
     set_repo_path(&opts.repo);
 
     let patch_env = PathEnvironment::new_patches();
     let clusters = get_clusters(&patch_env);
 
+    if clusters.is_empty() {
+        return Err(Error::NoClustersFound);
+    }
+
     let path = opts.repo.join("rendered");
     if path.exists() {
         std::fs::remove_dir_all(&path).unwrap();
@@ -34,18 +45,22 @@ fn generate(opts: &GlobalOpts) {
 
         std::fs::write(path.join(template_name), content).unwrap();
     }
+
+    Ok(())
 }
 
-fn main() {
+fn main() -> Result<(), Error> {
     let cli = Cli::parse();
 
     match cli.command {
-        Commands::Generate => generate(&cli.global_opts),
+        Commands::Generate => generate(&cli.global_opts)?,
         Commands::ShellCompletions => generate_complete(
             Shell::from_env().unwrap_or(Shell::Bash),
             &mut Cli::command(),
             "crete",
             &mut std::io::stdout(),
         ),
-    }
+    };
+
+    Ok(())
 }