feat(prompt): null handling and help command

2 files changed, 25 insertions, 5 deletions

diff --git a/src/prompt/builtins.rs b/src/prompt/builtins.rs
index dbbe3de..1c8389f 100644
--- a/src/prompt/builtins.rs
+++ b/src/prompt/builtins.rs
@@ -7,6 +7,8 @@ pub enum BuiltIn {
   Echo,
   History,
   Exit,
+  Null,
+  Help,
 }
 impl FromStr for BuiltIn {
   type Err = ();
@@ -16,6 +18,8 @@ impl FromStr for BuiltIn {
       "echo" => Ok(BuiltIn::Echo),
       "history" => Ok(BuiltIn::History),
       "exit" => Ok(BuiltIn::Exit),
+      "null" => Ok(BuiltIn::Null),
+      "help" => Ok(BuiltIn::Help),
       _ => Err(()),
     }
   }
@@ -27,8 +31,18 @@ pub fn builtin_echo(args: &[String]) -> i32 {
 }
 
 pub fn builtin_history(history: Vec<String>) -> i32 {
-  for cmd in history {
-    println!("{}", cmd.trim());
+  let mut index = 0;
+  for cmd in &history {
+    index += 1;
+    println!("{}  {}", index, cmd.trim());
   }
   0
 }
+
+pub fn builtin_help() -> i32 {
+  println!(
+    "echo    - display a line of text\nhistory - manipulate the history list\nexit    - end the \
+     application"
+  );
+  0
+}
diff --git a/src/prompt/mod.rs b/src/prompt/mod.rs
index d62db10..47a65e5 100644
--- a/src/prompt/mod.rs
+++ b/src/prompt/mod.rs
@@ -9,7 +9,7 @@ use std::{io, io::Write, str::FromStr};
 use crate::{
   config::Config,
   prompt::{
-    builtins::{builtin_echo, builtin_history, BuiltIn},
+    builtins::{builtin_echo, builtin_help, builtin_history, BuiltIn},
     structure::Command,
   },
 };
@@ -43,7 +43,11 @@ impl Prompt {
       .read_line(&mut input)
       .expect("failed to read command from stdin");
 
-    self.history.push(input.clone());
+    if input.len() > 2 {
+      self.history.push(input.clone());
+    } else {
+      input = "null".to_string();
+    }
 
     input
   }
@@ -64,8 +68,10 @@ impl Prompt {
       Ok(BuiltIn::Echo) => builtin_echo(&c.args),
       Ok(BuiltIn::Exit) => std::process::exit(0),
       Ok(BuiltIn::History) => builtin_history(history),
+      Ok(BuiltIn::Null) => 0,
+      Ok(BuiltIn::Help) => builtin_help(),
       _ => {
-        println!("{}: command not found", &c.keyword);
+        println!("wsh: command not found: {}", &c.keyword);
         1
       }
     }