From 92276a720e92a51ea657b96df24fc4a411a5d497 Mon Sep 17 00:00:00 2001
From: dusk <y.bera003.06@protonmail.com>
Date: Fri, 24 Jan 2025 04:13:06 +0900
Subject: [PATCH] refactor(command_parser): remove the Empty token, we don't
 need it

---
 crates/command_parser/src/command.rs |  2 +-
 crates/command_parser/src/token.rs   |  8 --------
 crates/command_parser/src/tree.rs    | 12 +++---------
 crates/commands/src/main.rs          |  6 +++---
 4 files changed, 7 insertions(+), 21 deletions(-)

diff --git a/crates/command_parser/src/command.rs b/crates/command_parser/src/command.rs
index b7fd65ce..6810a82d 100644
--- a/crates/command_parser/src/command.rs
+++ b/crates/command_parser/src/command.rs
@@ -30,7 +30,7 @@ impl Command {
                     parse_flags_before = idx;
                     was_parameter = true;
                 }
-                Token::Empty | Token::Value { .. } => {
+                Token::Value { .. } => {
                     if was_parameter {
                         break;
                     }
diff --git a/crates/command_parser/src/token.rs b/crates/command_parser/src/token.rs
index 79300279..b737a8cd 100644
--- a/crates/command_parser/src/token.rs
+++ b/crates/command_parser/src/token.rs
@@ -6,10 +6,6 @@ use crate::parameter::{Parameter, ParameterKind, ParameterValue};
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub enum Token {
-    /// Token used to represent a finished command (i.e. no more parameters required)
-    // todo: this is likely not the right way to represent this
-    Empty,
-
     /// A bot-defined command / subcommand (usually) (eg. "member" in `pk;member MyName`)
     Value {
         name: SmolStr,
@@ -69,8 +65,6 @@ impl Token {
             None => {
                 // short circuit on:
                 return match self {
-                    // empty token
-                    Self::Empty => Some(Ok(None)),
                     // missing paramaters
                     Self::Parameter(param) => Some(Err(TokenMatchError::MissingParameter {
                         name: param.name().into(),
@@ -85,7 +79,6 @@ impl Token {
 
         // try actually matching stuff
         match self {
-            Self::Empty => None,
             Self::Value { name, aliases } => (aliases.iter().chain(std::iter::once(name)))
                 .any(|v| v.eq(input))
                 .then(|| TokenMatchValue::new_match(input))
@@ -104,7 +97,6 @@ impl Token {
 impl Display for Token {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
-            Self::Empty => write!(f, ""),
             Self::Value { name, .. } => write!(f, "{name}"),
             Self::Parameter(param) => param.kind().format(f, param.name()),
         }
diff --git a/crates/command_parser/src/tree.rs b/crates/command_parser/src/tree.rs
index 53057a69..9b1466a3 100644
--- a/crates/command_parser/src/tree.rs
+++ b/crates/command_parser/src/tree.rs
@@ -28,14 +28,8 @@ impl TreeBranch {
                 .entry(token)
                 .or_insert_with(TreeBranch::default);
         }
-        // when we're out of tokens, add an Empty branch with the callback and no sub-branches
-        current_branch.branches.insert(
-            Token::Empty,
-            TreeBranch {
-                branches: OrderMap::new(),
-                current_command: Some(command),
-            },
-        );
+        // when we're out of tokens add the command to the last branch
+        current_branch.current_command = Some(command);
     }
 
     pub fn command(&self) -> Option<Command> {
@@ -61,7 +55,7 @@ impl TreeBranch {
         for branch in self.branches.values() {
             if let Some(command) = branch.current_command.as_ref() {
                 commands = box_iter(commands.chain(std::iter::once(command)));
-                // we dont need to look further if we found a command (only Empty tokens have commands)
+                // we dont need to look further if we found a command
                 continue;
             }
             commands = box_iter(commands.chain(branch.possible_commands(max_depth - 1)));
diff --git a/crates/commands/src/main.rs b/crates/commands/src/main.rs
index 2c863447..376d2469 100644
--- a/crates/commands/src/main.rs
+++ b/crates/commands/src/main.rs
@@ -1,6 +1,6 @@
 #![feature(iter_intersperse)]
 
-use command_parser::{token::Token, Tree};
+use command_parser::Tree;
 use commands::COMMAND_TREE;
 
 fn main() {
@@ -32,8 +32,8 @@ fn print_tree(tree: &Tree, depth: usize) {
             print!("-");
         }
         print!("> {token:?}");
-        if matches!(token, Token::Empty) {
-            println!(": {}", branch.command().unwrap().cb)
+        if let Some(command) = branch.command() {
+            println!(": {}", command.cb)
         } else {
             print_tree(branch, depth + 1)
         }