From 2c485cf046d68c232ca1f10180513bc6df6e03d4 Mon Sep 17 00:00:00 2001
From: Jeff <dev@jeffa.io>
Date: Mon, 23 Sep 2024 04:01:36 -0400
Subject: [PATCH] Implement logical and/or operators

---
 dust-lang/src/parser/mod.rs   | 63 ++++++++++++++++++++++++++++++++++-
 dust-lang/src/parser/tests.rs | 10 +++---
 dust-lang/src/vm.rs           |  2 +-
 3 files changed, 69 insertions(+), 6 deletions(-)

diff --git a/dust-lang/src/parser/mod.rs b/dust-lang/src/parser/mod.rs
index f5780a5..380efa9 100644
--- a/dust-lang/src/parser/mod.rs
+++ b/dust-lang/src/parser/mod.rs
@@ -547,7 +547,68 @@ impl<'src> Parser<'src> {
     }
 
     fn parse_logical_binary(&mut self) -> Result<(), ParseError> {
-        todo!()
+        let (left_instruction, left_position) =
+            self.chunk.pop_instruction(self.current_position)?;
+        let (push_back_left, left_is_constant, _) =
+            self.handle_binary_argument(&left_instruction)?;
+
+        let operator = self.current_token;
+        let operator_position = self.current_position;
+        let rule = ParseRule::from(&operator.kind());
+
+        let mut instruction = match operator.kind() {
+            TokenKind::DoubleAmpersand => Instruction::test(self.current_register, true),
+            TokenKind::DoublePipe => Instruction::test(self.current_register, false),
+            _ => {
+                return Err(ParseError::ExpectedTokenMultiple {
+                    expected: &[TokenKind::DoubleAmpersand, TokenKind::DoublePipe],
+                    found: operator.to_owned(),
+                    position: operator_position,
+                })
+            }
+        };
+
+        if let Operation::LoadBoolean = left_instruction.operation() {
+            self.increment_register()?;
+        }
+
+        self.advance()?;
+        self.parse(rule.precedence.increment())?;
+
+        let (mut right_instruction, right_position) =
+            self.chunk.pop_instruction(self.current_position)?;
+        let (push_back_right, right_is_constant, _) =
+            self.handle_binary_argument(&right_instruction)?;
+
+        if left_is_constant {
+            instruction.set_first_argument_to_constant();
+        }
+
+        if right_is_constant {
+            if let Operation::LoadBoolean = right_instruction.operation() {
+                right_instruction.set_second_argument_to_boolean(true);
+            }
+
+            instruction.set_second_argument_to_constant();
+        }
+
+        if push_back_left {
+            self.emit_instruction(left_instruction, left_position);
+        }
+
+        self.emit_instruction(instruction, operator_position);
+        self.emit_instruction(Instruction::jump(1, true), operator_position);
+
+        if push_back_right {
+            self.emit_instruction(right_instruction, right_position);
+        }
+
+        self.emit_instruction(
+            Instruction::r#move(self.current_register, self.current_register - 1),
+            operator_position,
+        );
+
+        Ok(())
     }
 
     fn parse_variable(
diff --git a/dust-lang/src/parser/tests.rs b/dust-lang/src/parser/tests.rs
index 525e946..e8e13fe 100644
--- a/dust-lang/src/parser/tests.rs
+++ b/dust-lang/src/parser/tests.rs
@@ -457,6 +457,7 @@ fn or() {
         parse("true || false"),
         Ok(Chunk::with_data(
             vec![
+                (Instruction::load_boolean(0, true, false), Span(0, 4)),
                 (
                     *Instruction::test(0, false)
                         .set_second_argument_to_constant()
@@ -464,8 +465,8 @@ fn or() {
                     Span(5, 7)
                 ),
                 (Instruction::jump(1, true), Span(5, 7)),
-                (Instruction::load_boolean(0, true, false), Span(0, 4)),
-                (Instruction::load_boolean(1, false, false), Span(8, 13)),
+                (Instruction::load_boolean(1, false, true), Span(8, 13)),
+                (Instruction::r#move(1, 0), Span(5, 7)),
             ],
             vec![],
             vec![]
@@ -479,6 +480,7 @@ fn and() {
         parse("true && false"),
         Ok(Chunk::with_data(
             vec![
+                (Instruction::load_boolean(0, true, false), Span(0, 4)),
                 (
                     *Instruction::test(0, true)
                         .set_second_argument_to_constant()
@@ -486,8 +488,8 @@ fn and() {
                     Span(5, 7)
                 ),
                 (Instruction::jump(1, true), Span(5, 7)),
-                (Instruction::load_boolean(0, true, false), Span(0, 4)),
-                (Instruction::load_boolean(1, false, false), Span(8, 13)),
+                (Instruction::load_boolean(1, false, true), Span(8, 13)),
+                (Instruction::r#move(1, 0), Span(5, 7)),
             ],
             vec![],
             vec![]
diff --git a/dust-lang/src/vm.rs b/dust-lang/src/vm.rs
index b30301a..dbdef8a 100644
--- a/dust-lang/src/vm.rs
+++ b/dust-lang/src/vm.rs
@@ -86,7 +86,7 @@ impl Vm {
 
                     self.insert(value, to_register, position)?;
 
-                    if boolean && skip {
+                    if skip {
                         self.ip += 1;
                     }
                 }