1 files changed, 51 insertions, 0 deletions
diff --git a/js/src/tests/test262/built-ins/TypedArray/prototype/findLast/BigInt/return-undefined-if-predicate-returns-false-value.js b/js/src/tests/test262/built-ins/TypedArray/prototype/findLast/BigInt/return-undefined-if-predicate-returns-false-value.js
new file mode 100644
index 0000000000..239455b309
--- /dev/null
+++ b/js/src/tests/test262/built-ins/TypedArray/prototype/findLast/BigInt/return-undefined-if-predicate-returns-false-value.js
@@ -0,0 +1,51 @@
+// Copyright (C) 2021 Microsoft. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-%typedarray%.prototype.findlast
+description: >
+  Return undefined if predicate always returns a boolean false value.
+info: |
+  %TypedArray%.prototype.findLast (predicate [ , thisArg ] )
+
+  ...
+  6. 6. Repeat, while k ≥ 0
+    ...
+    c. Let testResult be ! ToBoolean(? Call(predicate, thisArg, « kValue, 𝔽(k), O »)).
+    ...
+  7. Return undefined.
+includes: [testBigIntTypedArray.js]
+features: [BigInt, Symbol, TypedArray, array-find-from-last]
+---*/
+
+testWithBigIntTypedArrayConstructors(function(TA) {
+  var sample = new TA(3);
+  var called = 0;
+
+  var result = sample.findLast(function() {
+    called++;
+    return false;
+  });
+
+  assert.sameValue(called, 3, "predicate was called three times");
+  assert.sameValue(result, undefined);
+
+  result = sample.findLast(function() { return ""; });
+  assert.sameValue(result, undefined, "ToBoolean(empty string)");
+
+  result = sample.findLast(function() { return undefined; });
+  assert.sameValue(result, undefined, "ToBoolean(undefined)");
+
+  result = sample.findLast(function() { return null; });
+  assert.sameValue(result, undefined, "ToBoolean(null)");
+
+  result = sample.findLast(function() { return 0; });
+  assert.sameValue(result, undefined, "ToBoolean(0)");
+
+  result = sample.findLast(function() { return -0; });
+  assert.sameValue(result, undefined, "ToBoolean(-0)");
+
+  result = sample.findLast(function() { return NaN; });
+  assert.sameValue(result, undefined, "ToBoolean(NaN)");
+});
+
+reportCompare(0, 0);