Handle different declaration types

boa-dev · Mar 17, 2021 · 4749c3a · 4749c3a
1 parent 25a55c1
commit 4749c3a
Showing 1 changed file with 22 additions and 12 deletions.
diff --git a/boa/src/syntax/ast/node/declaration/mod.rs b/boa/src/syntax/ast/node/declaration/mod.rs
@@ -61,18 +61,28 @@ impl Executable for DeclarationList {
                 (_, Some(init)) => init.run(context)?,
                 (_, None) => Value::undefined(),
             };
-            context
-                .realm_mut()
-                .environment
-                .create_mutable_binding(
-                    decl.name().to_owned(),
-                    false,
-                    match &self.declaration_type {
-                        Var => VariableScope::Function,
-                        _ => VariableScope::Block,
-                    },
-                )
-                .map_err(|e| e.to_error(context))?;
+
+            let environment = &mut context.realm_mut().environment;
+
+            if self.declaration_type == Var && environment.has_binding(decl.name()) {
+                environment
+                    .set_mutable_binding(decl.name(), val, true)
+                    .map_err(|e| e.to_error(context))?;
+                return Ok(Value::undefined());
+            }
+
+            match &self.declaration_type {
+                Const => environment
+                    .create_immutable_binding(decl.name().to_owned(), false, VariableScope::Block)
+                    .map_err(|e| e.to_error(context))?,
+                Let => environment
+                    .create_mutable_binding(decl.name().to_owned(), false, VariableScope::Block)
+                    .map_err(|e| e.to_error(context))?,
+                Var => environment
+                    .create_mutable_binding(decl.name().to_owned(), false, VariableScope::Function)
+                    .map_err(|e| e.to_error(context))?,
+            }
+
             context
                 .realm_mut()
                 .environment