Extract scoping

src/twopass.rs

@@ -66,6 +66,12 @@ mod scope {
 		scope: HashMap<ast::Ident, Ident>,
 	}
 
+	#[derive(Debug, Clone, Default)]
+	pub struct ScopeInfo {
+		pub locals: Vec<ast::Ident>,
+		pub upvalues: Vec<(ast::Ident, Ident)>,
+	}
+
 	impl Scope {
 		pub fn new_toplevel() -> Self {
 			Self {
@@ -77,6 +83,13 @@ mod scope {
 			}
 		}
 
+		pub fn finish(self) -> ScopeInfo {
+			ScopeInfo {
+				locals: self.locals,
+				upvalues: self.upvalues,
+			}
+		}
+
 		pub fn lookup(&self, name: &ast::Ident) -> Option<Ident> {
 			self.scope.get(name).copied()
 		}
@@ -210,11 +223,12 @@ fn build_function(parent: &BuildContext<'_>, code: &ast::Function) -> Function {
 			}
 		}
 	}
+	let scope = scope.scope.into_inner().finish();
 	Function {
 		name: code.name.clone(),
 		args: code.args.clone(),
-		locals: vec![],
-		upvalues: vec![],
+		locals: scope.locals,
+		upvalues: scope.upvalues,
 		body,
 		ret: Box::new(Expression::Constant(ast::Constant::Nil)),
 	}