Improve on proof of concept

dust-lang/src/chunk.rs

@@ -253,7 +253,7 @@ impl<'a> ChunkDisassembler<'a> {
         "Instructions",
         "------------",
         "OFFSET OPERATION      INFO                      POSITION",
-        "------- -------------- ------------------------- --------",
+        "------ -------------- ------------------------- --------",
     ];
 
     const CONSTANT_HEADER: [&'static str; 5] = [
@@ -312,6 +312,22 @@ impl<'a> ChunkDisassembler<'a> {
 
         disassembled.push_str(&name_line);
 
+        let info_line = center(&format!(
+            "{} instructions, {} constants, {} locals",
+            self.chunk.instructions.len(),
+            self.chunk.constants.len(),
+            self.chunk.locals.len()
+        ));
+        let styled_info_line = {
+            if self.styled {
+                info_line.bold().dimmed().to_string()
+            } else {
+                info_line
+            }
+        };
+
+        disassembled.push_str(&styled_info_line);
+
         for line in Self::INSTRUCTION_HEADER {
             disassembled.push_str(&style(center(line)));
         }
@@ -321,9 +337,9 @@ impl<'a> ChunkDisassembler<'a> {
             let operation = instruction.operation().to_string();
             let info_option = instruction.disassembly_info(Some(self.chunk));
             let instruction_display = if let Some(info) = info_option {
-                format!("{offset:<7} {operation:14} {info:25} {position:8}")
+                format!("{offset:<6} {operation:14} {info:25} {position:8}")
             } else {
-                format!("{offset:<7} {operation:14} {:25} {position:8}", " ")
+                format!("{offset:<6} {operation:14} {:25} {position:8}", " ")
             };
 
             disassembled.push_str(&center(&instruction_display));
@@ -396,14 +412,14 @@ impl<'a> ChunkDisassembler<'a> {
     /// The capacity is calculated as follows:
     ///     - Get the number of static lines, i.e. lines that are always present in the disassembly
     ///     - Get the number of dynamic lines, i.e. lines that are generated from the chunk
-    ///     - Add 1 to the width to account for the newline character
+    ///     - Add an one to the width to account for the newline character
     ///     - Multiply the total number of lines by the width of the disassembly output
     ///
     /// The result is accurate only if the output is not styled. Otherwise the extra bytes added by
     /// the ANSI escape codes will make the result too low. It still works as a lower bound in that
     /// case.
     fn predict_length(&self) -> usize {
-        const EXTRA_LINES: usize = 1; // There is one empty line after the name of the chunk
+        const EXTRA_LINES: usize = 2; // There is one empty line after the name of the chunk
 
         let static_line_count =
             Self::INSTRUCTION_HEADER.len() + Self::CONSTANT_HEADER.len() + Self::LOCAL_HEADER.len();

dust-lang/src/parser/mod.rs

@@ -223,7 +223,16 @@ impl<'src> Parser<'src> {
 
     fn parse_grouped(&mut self, _allow_assignment: bool) -> Result<(), ParseError> {
         self.parse_expression()?;
-        self.expect(TokenKind::RightParenthesis)
+
+        if self.previous_token == Token::RightParenthesis {
+            Ok(())
+        } else {
+            Err(ParseError::ExpectedToken {
+                expected: TokenKind::RightParenthesis,
+                found: self.current_token.to_owned(),
+                position: self.current_position,
+            })
+        }
     }
 
     fn parse_unary(&mut self, _allow_assignment: bool) -> Result<(), ParseError> {
@@ -256,12 +265,21 @@ impl<'src> Parser<'src> {
         self.parse(rule.precedence.increment())?;
 
         let mut push_back_right = false;
+        let mut push_back_left = false;
+        let mut right_is_constant = false;
+        let mut left_is_constant = false;
+
         let (right_instruction, right_position) =
             self.chunk.pop_instruction(self.current_position)?;
         let right = match right_instruction.operation() {
             Operation::LoadConstant => {
-                self.decrement_register()?;
+                right_is_constant = true;
 
+                self.decrement_register()?;
+                right_instruction.first_argument()
+            }
+            Operation::GetLocal => {
+                self.decrement_register()?;
                 right_instruction.first_argument()
             }
             _ => {
@@ -270,19 +288,27 @@ impl<'src> Parser<'src> {
                 self.current_register - 1
             }
         };
-        let mut push_back_left = false;
         let (left_instruction, left_position) =
             self.chunk.pop_instruction(self.current_position)?;
         let left = match left_instruction.operation() {
             Operation::LoadConstant => {
-                self.decrement_register()?;
+                left_is_constant = true;
 
+                self.decrement_register()?;
+                left_instruction.first_argument()
+            }
+            Operation::GetLocal => {
+                self.decrement_register()?;
                 left_instruction.first_argument()
             }
             _ => {
                 push_back_left = true;
 
+                if push_back_right {
                     self.current_register - 2
+                } else {
+                    self.current_register - 1
+                }
             }
         };
 
@@ -313,11 +339,11 @@ impl<'src> Parser<'src> {
             }
         };
 
-        if !push_back_left {
+        if left_is_constant {
             instruction.set_first_argument_to_constant();
         }
 
-        if !push_back_right {
+        if right_is_constant {
             instruction.set_second_argument_to_constant();
         }
 
@@ -510,7 +536,7 @@ impl<'src> Parser<'src> {
                     position: self.previous_position,
                 });
             };
-        let allow_assignment = precedence <= Precedence::Assignment;
+        let allow_assignment = precedence < Precedence::Assignment;
 
         prefix_parser(self, allow_assignment)?;
 

dust-lang/src/parser/tests.rs

@@ -2,6 +2,30 @@ use crate::Local;
 
 use super::*;
 
+#[test]
+fn add_multiply_precedence() {
+    assert_eq!(
+        parse("1 + 2 * 3"),
+        Ok(Chunk::with_data(
+            vec![
+                (
+                    *Instruction::multiply(0, 1, 2)
+                        .set_first_argument_to_constant()
+                        .set_second_argument_to_constant(),
+                    Span(6, 7)
+                ),
+                (
+                    *Instruction::add(1, 0, 0).set_first_argument_to_constant(),
+                    Span(2, 3)
+                ),
+                (Instruction::r#return(), Span(0, 9)),
+            ],
+            vec![Value::integer(1), Value::integer(2), Value::integer(3)],
+            vec![]
+        ))
+    );
+}
+
 #[test]
 fn let_statement() {
     assert_eq!(