From 87951ab12ff2418983e248fdd774f0296186e218 Mon Sep 17 00:00:00 2001
From: Devin Bidwell <dbidwell94@biddydev.com>
Date: Mon, 29 Dec 2025 22:33:16 -0700
Subject: [PATCH] Support tuple assignment expressions and tuple assignments
 and declarations with function invocations

---
 rust_compiler/libs/parser/src/lib.rs       | 40 +++++++++++++---
 rust_compiler/libs/parser/src/test/mod.rs  | 53 ++++++++++++++++++++++
 rust_compiler/libs/parser/src/tree_node.rs | 20 ++++++++
 3 files changed, 106 insertions(+), 7 deletions(-)

diff --git a/rust_compiler/libs/parser/src/lib.rs b/rust_compiler/libs/parser/src/lib.rs
index c8b3340..1d7d0c3 100644
--- a/rust_compiler/libs/parser/src/lib.rs
+++ b/rust_compiler/libs/parser/src/lib.rs
@@ -1086,17 +1086,43 @@ impl<'a> Parser<'a> {
                     end_col: right.span.end_col,
                 };
 
+                // Check if the left side is a tuple, and if so, create a TupleAssignment
+                let node = if let Expression::Tuple(tuple_expr) = &left.node {
+                    // Extract variable names from the tuple, handling underscores
+                    let mut names = Vec::new();
+                    for item in &tuple_expr.node {
+                        if let Expression::Variable(var) = &item.node {
+                            names.push(var.clone());
+                        } else {
+                            return Err(Error::InvalidSyntax(
+                                item.span,
+                                String::from("Tuple assignment can only contain variable names"),
+                            ));
+                        }
+                    }
+                    
+                    Expression::TupleAssignment(Spanned {
+                        span,
+                        node: TupleAssignmentExpression {
+                            names,
+                            value: boxed!(right),
+                        },
+                    })
+                } else {
+                    Expression::Assignment(Spanned {
+                        span,
+                        node: AssignmentExpression {
+                            assignee: boxed!(left),
+                            expression: boxed!(right),
+                        },
+                    })
+                };
+
                 expressions.insert(
                     i,
                     Spanned {
                         span,
-                        node: Expression::Assignment(Spanned {
-                            span,
-                            node: AssignmentExpression {
-                                assignee: boxed!(left),
-                                expression: boxed!(right),
-                            },
-                        }),
+                        node,
                     },
                 );
             }
diff --git a/rust_compiler/libs/parser/src/test/mod.rs b/rust_compiler/libs/parser/src/test/mod.rs
index eb5a3fc..ce91237 100644
--- a/rust_compiler/libs/parser/src/test/mod.rs
+++ b/rust_compiler/libs/parser/src/test/mod.rs
@@ -200,3 +200,56 @@ fn test_tuple_declaration() -> Result<()> {
 
     Ok(())
 }
+#[test]
+fn test_tuple_assignment() -> Result<()> {
+    let expr = parser!("(x, y) = (1, 2);").parse()?.unwrap();
+
+    assert_eq!("((x, y) = (1, 2))", expr.to_string());
+
+    Ok(())
+}
+
+#[test]
+fn test_tuple_assignment_with_underscore() -> Result<()> {
+    let expr = parser!("(x, _) = (1, 2);").parse()?.unwrap();
+
+    assert_eq!("((x, _) = (1, 2))", expr.to_string());
+
+    Ok(())
+}
+
+#[test]
+fn test_tuple_declaration_with_function_call() -> Result<()> {
+    let expr = parser!("let (x, y) = doSomething();").parse()?.unwrap();
+
+    assert_eq!("(let (x, y) = doSomething())", expr.to_string());
+
+    Ok(())
+}
+
+#[test]
+fn test_tuple_declaration_with_function_call_with_underscore() -> Result<()> {
+    let expr = parser!("let (x, _) = doSomething();").parse()?.unwrap();
+
+    assert_eq!("(let (x, _) = doSomething())", expr.to_string());
+
+    Ok(())
+}
+
+#[test]
+fn test_tuple_assignment_with_function_call() -> Result<()> {
+    let expr = parser!("(x, y) = doSomething();").parse()?.unwrap();
+
+    assert_eq!("((x, y) = doSomething())", expr.to_string());
+
+    Ok(())
+}
+
+#[test]
+fn test_tuple_assignment_with_function_call_with_underscore() -> Result<()> {
+    let expr = parser!("(x, _) = doSomething();").parse()?.unwrap();
+
+    assert_eq!("((x, _) = doSomething())", expr.to_string());
+
+    Ok(())
+}
diff --git a/rust_compiler/libs/parser/src/tree_node.rs b/rust_compiler/libs/parser/src/tree_node.rs
index 1534c4f..3da1305 100644
--- a/rust_compiler/libs/parser/src/tree_node.rs
+++ b/rust_compiler/libs/parser/src/tree_node.rs
@@ -263,6 +263,24 @@ impl<'a> std::fmt::Display for TupleDeclarationExpression<'a> {
     }
 }
 
+#[derive(Debug, PartialEq, Eq)]
+pub struct TupleAssignmentExpression<'a> {
+    pub names: Vec<Spanned<Cow<'a, str>>>,
+    pub value: Box<Spanned<Expression<'a>>>,
+}
+
+impl<'a> std::fmt::Display for TupleAssignmentExpression<'a> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let names = self
+            .names
+            .iter()
+            .map(|n| n.node.to_string())
+            .collect::<Vec<_>>()
+            .join(", ");
+        write!(f, "(({}) = {})", names, self.value)
+    }
+}
+
 #[derive(Debug, PartialEq, Eq)]
 pub struct IfExpression<'a> {
     pub condition: Box<Spanned<Expression<'a>>>,
@@ -367,6 +385,7 @@ pub enum Expression<'a> {
     Syscall(Spanned<SysCall<'a>>),
     Ternary(Spanned<TernaryExpression<'a>>),
     Tuple(Spanned<Vec<Spanned<Expression<'a>>>>),
+    TupleAssignment(Spanned<TupleAssignmentExpression<'a>>),
     TupleDeclaration(Spanned<TupleDeclarationExpression<'a>>),
     Variable(Spanned<Cow<'a, str>>),
     While(Spanned<WhileExpression<'a>>),
@@ -413,6 +432,7 @@ impl<'a> std::fmt::Display for Expression<'a> {
                     .join(", ");
                 write!(f, "({})", items)
             }
+            Expression::TupleAssignment(e) => write!(f, "{}", e),
             Expression::TupleDeclaration(e) => write!(f, "{}", e),
             Expression::Variable(id) => write!(f, "{}", id),
             Expression::While(e) => write!(f, "{}", e),