From e9675cd5d2e24e5a2550e92b7b40406a80a95217 Mon Sep 17 00:00:00 2001
From: Devin Bidwell <dbidwell94@biddydev.com>
Date: Fri, 22 Nov 2024 02:29:27 -0700
Subject: [PATCH] Binary expressions are buggy. Priorities are good, but the l
 and r are flipped _sometimes_

---
 src/parser/mod.rs | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/src/parser/mod.rs b/src/parser/mod.rs
index 939394f..dbf0f0a 100644
--- a/src/parser/mod.rs
+++ b/src/parser/mod.rs
@@ -4,6 +4,7 @@ use crate::tokenizer::{
     token::{Keyword, Symbol, Token, TokenType},
     Tokenizer, TokenizerBuffer, TokenizerError,
 };
+use std::io::SeekFrom;
 use thiserror::Error;
 use tree_node::*;
 
@@ -250,7 +251,6 @@ impl Parser {
             };
         }
 
-
         // We cannot use recursion here, as we need to handle the precedence of the operators
         // We need to use a loop to parse the binary expressions.
 
@@ -280,11 +280,6 @@ impl Parser {
 
         // build the expressions and operators vectors
         while token_matches!(current_token, TokenType::Symbol(s) if s.is_operator()) {
-            println!(
-                "Looped: expressions len: {}, operators len: {}",
-                expressions.len(),
-                operators.len()
-            );
             // We are guaranteed to have an operator symbol here as we checked in the while loop
             let operator = extract_token_data!(current_token, TokenType::Symbol(ref s), s.clone());
             operators.push(operator);
@@ -352,7 +347,7 @@ impl Parser {
         // Loop through operators, and build the binary expressions for addition and subtraction operators
         for (i, operator) in operators.iter().enumerate() {
             if operator == &Symbol::Plus || operator == &Symbol::Minus {
-                let left = expressions.remove(i);
+                let left = expressions.remove(min!(i, expressions.len() - 1));
                 let right = expressions.remove(min!(i, expressions.len() - 1));
 
                 match operator {
@@ -387,6 +382,11 @@ impl Parser {
             });
         }
 
+        // Edge case. If the current token is a semi-colon, we need to set current token to the previous token
+        if token_matches!(current_token, TokenType::Symbol(Symbol::Semicolon)) {
+            self.tokenizer.seek(SeekFrom::Current(-1))?;
+        }
+
         // Ensure the last expression is a binary expression
         match expressions.pop().unwrap() {
             Expression::BinaryExpression(binary) => Ok(binary),
@@ -751,6 +751,11 @@ mod tests {
         let expr = parser!("1 + 3 ^ 5").parse()?.unwrap();
         assert_eq!("(1 + (3 ^ 5))", expr.to_string());
 
+        let input = "4 ^ 2 + 3 ^ 2";
+
+        let expr = parser!(input).parse()?.unwrap();
+        println!("Original: {}\nTranscribed: {}", input, expr.to_string());
+
         let expr = parser!("12 - 1 + 3 * 5").parse()?.unwrap();
 
         assert_eq!("((12 - 1) + (3 * 5))", expr.to_string());