1 files changed, 34 insertions, 0 deletions
diff --git a/js/src/tests/test262/built-ins/TypedArray/prototype/findLastIndex/length.js b/js/src/tests/test262/built-ins/TypedArray/prototype/findLastIndex/length.js
new file mode 100644
index 0000000000..9586c335a5
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+++ b/js/src/tests/test262/built-ins/TypedArray/prototype/findLastIndex/length.js
@@ -0,0 +1,34 @@
+// Copyright (C) 2021 Microsoft. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-%typedarray%.prototype.findlastindex
+description: >
+  %TypedArray%.prototype.findLastIndex.length is 1.
+info: |
+  %TypedArray%.prototype.findLastIndex (predicate [ , thisArg ] )
+
+  17 ECMAScript Standard Built-in Objects:
+    Every built-in Function object, including constructors, has a length
+    property whose value is an integer. Unless otherwise specified, this
+    value is equal to the largest number of named arguments shown in the
+    subclause headings for the function description, including optional
+    parameters. However, rest parameters shown using the form “...name”
+    are not included in the default argument count.
+
+    Unless otherwise specified, the length property of a built-in Function
+    object has the attributes { [[Writable]]: false, [[Enumerable]]: false,
+    [[Configurable]]: true }.
+includes: [propertyHelper.js, testTypedArray.js]
+features: [TypedArray, array-find-from-last]
+---*/
+
+assert.sameValue(TypedArray.prototype.findLastIndex.length, 1);
+
+verifyProperty(TypedArray.prototype.findLastIndex, "length", {
+  enumerable: false,
+  writable: false,
+  configurable: true
+});
+
+reportCompare(0, 0);