Improve REPL error handling

Author: garyttierney

crates/cli/src/repl.rs

@@ -6,41 +6,51 @@ use rustyline::{error::ReadlineError, DefaultEditor};
 
 use crate::Action;
 
+pub fn process_input(input: &str, dvd_bnd: &DvdBnd) -> Result<(), Box<dyn Error>> {
+    let args = shlex::split(input).ok_or("failed to parse input")?;
+
+    let command = Action::augment_subcommands(clap::Command::new("repl").no_binary_name(true));
+    let action = command
+        .clone()
+        .try_get_matches_from(args)
+        .and_then(|matches| Action::from_arg_matches(&matches))
+        .map_err(|e| e.to_string())?;
+
+    match action {
+        Action::Repl => {
+            println!("Already running repl.");
+            Ok(())
+        }
+        action => {
+            action.run(dvd_bnd)
+        }
+    }
+}
+
 pub fn begin(dvd_bnd: &DvdBnd) -> Result<(), Box<dyn Error>> {
     let mut rl = DefaultEditor::new()?;
     let _ = rl.load_history("history.txt");
 
-    let command = Action::augment_subcommands(clap::Command::new("repl").no_binary_name(true));
-
     loop {
         let readline = rl.readline(">> ");
+
         match readline {
             Ok(line) => {
                 rl.add_history_entry(line.as_str())?;
-                let args = shlex::split(&line).ok_or("failed to parse input")?;
-
-                let action = command
-                    .clone()
-                    .try_get_matches_from(args)
-                    .and_then(|matches| Action::from_arg_matches(&matches))
-                    .map_err(|e| e.to_string());
-
-                match action {
-                    Ok(Action::Repl) => {
-                        println!("Running repl inside repl doesn't make sense");
-                        continue;
-                    }
-                    Ok(action) => {
-                        let _ = action.run(dvd_bnd);
+
+                match process_input(&line, dvd_bnd) {
+                    Ok(_) => println!("Command successful"),
+                    Err(e) => {
+                        println!("{:#?}", e);
                     }
-                    Err(e) => println!("{}", e),
-                };
+                }
             }
             Err(ReadlineError::Interrupted) => {
-                println!("CTRL-C");
+                println!("^C");
+                continue;
             }
             Err(ReadlineError::Eof) => {
-                println!("CTRL-D");
+                println!("^D");
                 break;
             }
             Err(err) => {