From c0bfe06e4b19ec7eff7efddd164f65bf0e695eec Mon Sep 17 00:00:00 2001
From: Octavia Togami <octavia.togami@gmail.com>
Date: Sun, 21 Jun 2020 18:55:29 -0700
Subject: [PATCH] Set ES6 compat flag for Rhino

(cherry picked from commit 849a515d4a5c02c083e5ab343db40d7eb05b2f51)
---
 .../sk89q/worldedit/scripting/RhinoContextFactory.java    | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/scripting/RhinoContextFactory.java b/worldedit-core/src/main/java/com/sk89q/worldedit/scripting/RhinoContextFactory.java
index b61edb0d3..04f7cb399 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/scripting/RhinoContextFactory.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/scripting/RhinoContextFactory.java
@@ -35,6 +35,14 @@ public class RhinoContextFactory extends ContextFactory {
     @Override
     protected Context makeContext() {
         RhinoContext cx = new RhinoContext(this);
+        try {
+            // Try to set ES6 compat flag (since 1.7.7)
+            Context.class.getDeclaredField("VERSION_ES6");
+            cx.setLanguageVersion(RhinoContext.VERSION_ES6);
+        } catch (NoSuchFieldException e) {
+            // best we can do, compatible with 1.7R2 that many people probably use
+            cx.setLanguageVersion(Context.VERSION_1_7);
+        }
         cx.setInstructionObserverThreshold(10000);
         return cx;
     }