refactor(ses): Use Symbol.toStringTag over toString override

endojs · Nov 3, 2023 · 20d2f80 · 20d2f80
1 parent 68805fe
commit 20d2f80
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Showing 4 changed files with 29 additions and 12 deletions.
diff --git a/packages/ses/src/compartment.js b/packages/ses/src/compartment.js
@@ -8,9 +8,13 @@ import {
   TypeError,
   WeakMap,
   assign,
+  create,
   defineProperties,
   entries,
+  getOwnPropertyDescriptors,
+  objectPrototype,
   promiseThen,
+  toStringTagSymbol,
   weakmapGet,
   weakmapSet,
 } from './commons.js';
@@ -79,7 +83,7 @@ const compartmentImportNow = (compartment, specifier) => {
   return exportsProxy;
 };
 
-export const CompartmentPrototype = {
+const CompartmentPrototypeTemplate = {
   constructor: InertCompartment,
 
   get globalThis() {
@@ -105,10 +109,6 @@ export const CompartmentPrototype = {
     return compartmentEvaluate(compartmentFields, source, options);
   },
 
-  toString() {
-    return '[object Compartment]';
-  },
-
   module(specifier) {
     if (typeof specifier !== 'string') {
       throw TypeError('first argument of module() must be a string');
@@ -168,6 +168,22 @@ export const CompartmentPrototype = {
   },
 };
 
+const CompartmentPrototypeProperties = {
+  ...getOwnPropertyDescriptors(CompartmentPrototypeTemplate),
+
+  [toStringTagSymbol]: {
+    value: 'Compartment',
+    writable: false,
+    configurable: true,
+    enumerable: false,
+  },
+};
+
+export const CompartmentPrototype = create(
+  objectPrototype,
+  CompartmentPrototypeProperties,
+);
+
 defineProperties(InertCompartment, {
   prototype: { value: CompartmentPrototype },
 });

diff --git a/packages/ses/src/permits.js b/packages/ses/src/permits.js
@@ -1500,8 +1500,7 @@ export const permitted = {
     evaluate: fn,
     globalThis: getter,
     name: getter,
-    // Should this be proposed?
-    toString: fn,
+    '@@toStringTag': 'string',
     import: asyncFn,
     load: asyncFn,
     importNow: fn,

diff --git a/packages/ses/test/test-compartment-instance.js b/packages/ses/test/test-compartment-instance.js
@@ -28,11 +28,13 @@ test('Compartment instance', t => {
   );
 
   t.is(c.toString(), '[object Compartment]', 'toString()');
-  t.is(c[Symbol.toStringTag], undefined, '"Symbol.toStringTag" property');
+  t.is(c[Symbol.toStringTag], 'Compartment', '"Symbol.toStringTag" property');
 
   t.deepEqual(Reflect.ownKeys(c), [], 'static properties');
   t.deepEqual(
-    Reflect.ownKeys(Object.getPrototypeOf(c)).sort(),
+    Reflect.ownKeys(Object.getPrototypeOf(c))
+      .filter(key => typeof key !== 'symbol')
+      .sort(),
     [
       'constructor',
       'evaluate',
@@ -42,7 +44,6 @@ test('Compartment instance', t => {
       'load',
       'module',
       'name',
-      'toString',
     ].sort(),
     'prototype properties',
   );

diff --git a/packages/ses/test/test-compartment-prototype.js b/packages/ses/test/test-compartment-prototype.js
@@ -13,7 +13,9 @@ test('Compartment prototype', t => {
   );
 
   t.deepEqual(
-    Reflect.ownKeys(Compartment.prototype).sort(),
+    Reflect.ownKeys(Compartment.prototype)
+      .filter(key => typeof key !== 'symbol')
+      .sort(),
     [
       'constructor',
       'evaluate',
@@ -23,7 +25,6 @@ test('Compartment prototype', t => {
       'load',
       'module',
       'name',
-      'toString',
     ].sort(),
     'prototype properties',
   );