1 files changed, 56 insertions, 0 deletions
diff --git a/js/src/tests/test262/built-ins/Iterator/from/iterable-primitives.js b/js/src/tests/test262/built-ins/Iterator/from/iterable-primitives.js
new file mode 100644
index 0000000000..e441136b91
--- /dev/null
+++ b/js/src/tests/test262/built-ins/Iterator/from/iterable-primitives.js
@@ -0,0 +1,56 @@
+// |reftest| shell-option(--enable-iterator-helpers) skip-if(!this.hasOwnProperty('Iterator')||!xulRuntime.shell) -- iterator-helpers is not enabled unconditionally, requires shell-options
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iterator.from
+description: >
+  Iterator.from does not respect the iterability of any primitive except Strings
+info: |
+  Iterator.from ( O )
+
+  1. If O is a String, set O to ! ToObject(O).
+  2. Let iteratorRecord be ? GetIteratorFlattenable(O).
+
+includes: [compareArray.js]
+features: [iterator-helpers]
+flags: []
+---*/
+
+function* g() {
+  yield 0;
+}
+
+Number.prototype[Symbol.iterator] = function* () {
+  let i = 0;
+  let target = this >>> 0;
+  while (i < target) {
+    yield i;
+    ++i;
+  }
+};
+
+assert.compareArray(Array.from(5), [0, 1, 2, 3, 4]);
+
+assert.throws(TypeError, function () {
+  Iterator.from(5);
+});
+
+assert.compareArray(Array.from(Iterator.from(new Number(5))), [0, 1, 2, 3, 4]);
+
+assert.compareArray(Array.from(Iterator.from('string')), ['s', 't', 'r', 'i', 'n', 'g']);
+
+const originalStringIterator = String.prototype[Symbol.iterator];
+let observedType;
+Object.defineProperty(String.prototype, Symbol.iterator, {
+  get() {
+    'use strict';
+    observedType = typeof this;
+    return originalStringIterator;
+  }
+});
+Iterator.from('');
+assert.sameValue(observedType, 'string');
+Iterator.from(new String(''));
+assert.sameValue(observedType, 'object');
+
+reportCompare(0, 0);