From 068aa6c746d618c1ab149d65bcd323203b6004cc Mon Sep 17 00:00:00 2001
From: raskad <32105367+raskad@users.noreply.github.com>
Date: Tue, 19 Mar 2024 03:09:45 +0100
Subject: [PATCH] Add missing environment creation in initial iteration of for
 loop

---
 core/engine/src/bytecompiler/statement/loop.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/core/engine/src/bytecompiler/statement/loop.rs b/core/engine/src/bytecompiler/statement/loop.rs
index 4af3de4bff1..71c6f453e3f 100644
--- a/core/engine/src/bytecompiler/statement/loop.rs
+++ b/core/engine/src/bytecompiler/statement/loop.rs
@@ -59,6 +59,20 @@ impl ByteCompiler<'_> {
         }
 
         self.push_empty_loop_jump_control(use_expr);
+
+        if let Some((let_binding_indices, env_index)) = &let_binding_indices {
+            for index in let_binding_indices {
+                self.emit_with_varying_operand(Opcode::GetName, *index);
+            }
+
+            self.emit_opcode(Opcode::PopEnvironment);
+            self.emit_with_varying_operand(Opcode::PushDeclarativeEnvironment, *env_index);
+
+            for index in let_binding_indices.iter().rev() {
+                self.emit_with_varying_operand(Opcode::PutLexicalValue, *index);
+            }
+        }
+
         let initial_jump = self.jump();
         let start_address = self.next_opcode_location();