feat: list commands when no command is called

shell/src/ash.rs

@@ -3,7 +3,6 @@ use std::env;
 use std::process::Command as stdCommand;
 use std::io::{self, Write, ErrorKind};
 use std::path::Path;
-use std::fmt;
 
 pub struct Ash;
 

src/boxcmd.rs

@@ -13,6 +13,9 @@ impl Command for Boxcmd {
             registry.execute(cmd);
             return;
         }
-        println!("No command provided.");
+        println!(
+            "No command provided. Included commands:\n{}",
+            registry.list().join(", ")
+        );
     }
 }

utils/src/registry.rs

@@ -16,6 +16,14 @@ impl CommandRegistry {
         self.commands.insert(name.to_string(), command);
     }
 
+    pub fn list(&self) -> Vec<String> {
+        let mut bufvec = Vec::new();
+        for (key, _value) in self.commands.iter() {
+            bufvec.push(String::from(key))
+        }
+        bufvec
+    }
+
     pub fn get(&self, name: &str) -> Option<&Box<dyn Command>> {
         self.commands.get(name)
     }