Be safer about iterable.js property descriptors

diff --git a/iterable.js b/iterable.js
index 2eb9aa46120f0183796623854769d2e8f5f94cf7..7149a28fb4b836ee47f1c3a5aa7ad76a688fbb5b 100644 (file)
--- a/iterable.js
+++ b/iterable.js
@@ -9,11 +9,13 @@
 
 import { bind, call, identity } from "./function.js";
 import {
 
 import { bind, call, identity } from "./function.js";
 import {

+  defineOwnDataProperty,

   defineOwnProperty,
   getPrototype,
   objectCreate,
   defineOwnProperty,
   getPrototype,
   objectCreate,

+  setPropertyValues,

 } from "./object.js";
 } from "./object.js";

-import { ITERATOR, TO_STRING_TAG } from "./value.js";
+import { ITERATOR, TO_STRING_TAG, UNDEFINED } from "./value.js";

 
 export const {
   /**
 
 export const {
   /**


@@ -228,7 +230,7 @@ export const {
         const nextIterator = this.#nextIterator;
         if (baseIterator === null) {
           // The base iterator has already been exhausted.
         const nextIterator = this.#nextIterator;
         if (baseIterator === null) {
           // The base iterator has already been exhausted.

-          return { value: undefined, done: true };
+          return { value: UNDEFINED, done: true };

         } else if (nextIterator === null) {
           // This iterator is not currently yielding values from the
           // provided generator function, either because it doesn’t
         } else if (nextIterator === null) {
           // This iterator is not currently yielding values from the
           // provided generator function, either because it doesn’t


@@ -296,20 +298,20 @@ export const {
     objectCreate(
       iteratorPrototype,
       {
     objectCreate(
       iteratorPrototype,
       {

-        next: {
+        next: setPropertyValues(objectCreate(null), {

           configurable: true,
           enumerable: false,
           value: function next() {
             return call(iteratorNext, this, []);
           },
           writable: true,
           configurable: true,
           enumerable: false,
           value: function next() {
             return call(iteratorNext, this, []);
           },
           writable: true,

-        },
-        [TO_STRING_TAG]: {
+        }),
+        [TO_STRING_TAG]: setPropertyValues(objectCreate(null), {

           configurable: true,
           enumerable: false,
           value: stringTag,
           writable: false,
           configurable: true,
           enumerable: false,
           value: stringTag,
           writable: false,

-        },
+        }),

       },
     );
 
       },
     );
 


@@ -330,7 +332,7 @@ export const {
     stringTag = "Iterator",
   ) => {
     const prototype = makePrototype(stringTag); // intentionally cached
     stringTag = "Iterator",
   ) => {
     const prototype = makePrototype(stringTag); // intentionally cached

-    return ($, thisArg = undefined) =>
+    return ($, thisArg = UNDEFINED) =>

       new Iterator(
         prototype,
         call(makeBaseIterator, $, []),
       new Iterator(
         prototype,
         call(makeBaseIterator, $, []),


@@ -343,16 +345,20 @@ export const {
     arrayIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,
     arrayIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,

-        undefined,
+        UNDEFINED,

         [arrayIterator, arrayIteratorNext],
       ),
       "name",
         [arrayIterator, arrayIteratorNext],
       ),
       "name",

-      { value: "arrayIteratorFunction" },
+      defineOwnDataProperty(
+        objectCreate(null),
+        "value",
+        "arrayIteratorFunction",
+      ),

     ),
     generatorIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,
     ),
     generatorIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,

-        undefined,
+        UNDEFINED,

         [
           function () {
             return this();
         [
           function () {
             return this();


@@ -361,34 +367,50 @@ export const {
         ],
       ),
       "name",
         ],
       ),
       "name",

-      { value: "generatorIteratorFunction" },
+      defineOwnDataProperty(
+        objectCreate(null),
+        "value",
+        "generatorIteratorFunction",
+      ),

     ),
     mapIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,
     ),
     mapIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,

-        undefined,
+        UNDEFINED,

         [mapIterator, mapIteratorNext],
       ),
       "name",
         [mapIterator, mapIteratorNext],
       ),
       "name",

-      { value: "mapIteratorFunction" },
+      defineOwnDataProperty(
+        objectCreate(null),
+        "value",
+        "mapIteratorFunction",
+      ),

     ),
     setIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,
     ),
     setIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,

-        undefined,
+        UNDEFINED,

         [setIterator, setIteratorNext],
       ),
       "name",
         [setIterator, setIteratorNext],
       ),
       "name",

-      { value: "setIteratorFunction" },
+      defineOwnDataProperty(
+        objectCreate(null),
+        "value",
+        "setIteratorFunction",
+      ),

     ),
     stringIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,
     ),
     stringIteratorFunction: defineOwnProperty(
       bind(
         iteratorFunction,

-        undefined,
+        UNDEFINED,

         [stringIterator, stringIteratorNext],
       ),
       "name",
         [stringIterator, stringIteratorNext],
       ),
       "name",

-      { value: "stringIteratorFunction" },
+      defineOwnDataProperty(
+        objectCreate(null),
+        "value",
+        "stringIteratorFunction",
+      ),

     ),
   };
 })();
     ),
   };
 })();