Added history command.

src/shell/cmd/handler.rs

@@ -20,6 +20,10 @@ pub fn echo(state: State, matches: &ArgMatches) -> Result<State, String> {
     writer::msg(state, &msg)
 }
 
+pub fn history(state: State, _matches: &ArgMatches) -> Result<State, String> {
+    writer::msg(state.clone(), format_list(state.history).as_str())
+}
+
 pub fn ping(state: State, _matches: &ArgMatches) -> Result<State, String> {
     writer::msg(state, "pong")
 }
@@ -28,3 +32,12 @@ pub fn quit(mut state: State, _matches: &ArgMatches) -> Result<State, String> {
     state.quit = true;
     writer::msg(state, "\nQuitting ...\n")
 }
+
+// Private functions
+
+fn format_list(mut list: Vec<String>) -> String {
+    const PREFIX: &str = "  ";
+    let mut res: Vec<String> = vec![PREFIX.to_string()];
+    res.append(&mut list);
+    format!("\n{}{}\n", PREFIX, res.join(PREFIX).trim())
+}

src/shell/cmd/mod.rs

@@ -13,6 +13,7 @@ pub fn dispatch(state: State, line: &str) -> Result<State, String> {
     match matches.subcommand() {
         Some(("banner", matches)) => handler::banner(state.clone(), matches),
         Some(("echo", matches)) => handler::echo(state.clone(), matches),
+        Some(("history", matches)) => handler::history(state.clone(), matches),
         Some(("ping", matches)) => handler::ping(state.clone(), matches),
         Some(("quit", matches)) => handler::quit(state.clone(), matches),
         Some((name, _matches)) => unimplemented!("{name}"),
@@ -55,6 +56,12 @@ fn cmd() -> Command {
                         .value_parser(value_parser!(String)),
                 ),
         )
+        .subcommand(
+            Command::new("history")
+                .alias("hist")
+                .about("Show all commands entered so far")
+                .help_template(USAGE_TEMPLATE),
+        )
         .subcommand(
             Command::new("ping")
                 .about("Check for liveliness")