From a3a78ce6f540900ae9f069cfb55a9a0d9a841949 Mon Sep 17 00:00:00 2001
From: Jack Works <zjwpeter@gmail.com>
Date: Sat, 28 Sep 2019 10:49:40 +0800
Subject: [PATCH] fix: getPrototypeOf trap get called in safari

---
 src/scopeHandler.js         | 12 ++++++++++--
 test/module/scopeHandler.js |  5 +++--
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/scopeHandler.js b/src/scopeHandler.js
index 2bfae5e..db60667 100644
--- a/src/scopeHandler.js
+++ b/src/scopeHandler.js
@@ -8,7 +8,7 @@ import { throwTantrum } from './utilities';
  */
 const alwaysThrowHandler = new Proxy(freeze({}), {
   get(target, prop) {
-    throwTantrum(`unexpected scope handler trap called: ${prop}`);
+    throwTantrum(`unexpected scope handler trap called: ${String(prop)}`);
   }
 });
 
@@ -25,6 +25,8 @@ const alwaysThrowHandler = new Proxy(freeze({}), {
  * - route all other property lookups at the safeGlobal.
  * - hide the unsafeGlobal which lives on the scope chain above the 'with'.
  * - ensure the Proxy invariants despite some global properties being frozen.
+ *
+ * @returns {ProxyHandler<any> & Record<string, any>}
  */
 export function createScopeHandler(unsafeRec, safeGlobal, sloppyGlobals) {
   const { unsafeGlobal, unsafeEval } = unsafeRec;
@@ -79,7 +81,6 @@ export function createScopeHandler(unsafeRec, safeGlobal, sloppyGlobals) {
       return undefined;
     },
 
-    // eslint-disable-next-line class-methods-use-this
     set(target, prop, value) {
       // todo: allow modifications when target.hasOwnProperty(prop) and it
       // is writable, assuming we've already rejected overlap (see
@@ -134,6 +135,13 @@ export function createScopeHandler(unsafeRec, safeGlobal, sloppyGlobals) {
       }
 
       return false;
+    },
+
+    // note: this is likely a bug of safari
+    // https://bugs.webkit.org/show_bug.cgi?id=195534
+
+    getPrototypeOf() {
+      return null;
     }
   };
 }
diff --git a/test/module/scopeHandler.js b/test/module/scopeHandler.js
index cf7c1e5..af6f9cb 100644
--- a/test/module/scopeHandler.js
+++ b/test/module/scopeHandler.js
@@ -9,7 +9,9 @@ test('scope handler traps', t => {
 
   const handler = createScopeHandler({});
 
-  ['has', 'get', 'set'].forEach(trap => t.doesNotThrow(() => handler[trap]));
+  ['has', 'get', 'set', 'getPrototypeOf'].forEach(trap =>
+    t.doesNotThrow(() => handler[trap])
+  );
 
   [
     'apply',
@@ -17,7 +19,6 @@ test('scope handler traps', t => {
     'defineProperty',
     'delteProperty',
     'getOwnProperty',
-    'getPrototypeOf',
     'isExtensible',
     'ownKeys',
     'preventExtensions',