1 files changed, 26 insertions, 0 deletions
diff --git a/js/src/tests/test262/harness/assert-tostring.js b/js/src/tests/test262/harness/assert-tostring.js
new file mode 100644
index 0000000000..351607b020
--- /dev/null
+++ b/js/src/tests/test262/harness/assert-tostring.js
@@ -0,0 +1,26 @@
+// Copyright (C) 2019 Alexey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: >
+  When composing a message, errors from ToString are handled.
+features: [async-functions]
+---*/
+
+var threw = false;
+var asyncFunProto = Object.getPrototypeOf(async function() {});
+
+try {
+  assert(asyncFunProto);
+} catch (err) {
+  threw = true;
+  if (err.constructor !== Test262Error) {
+    throw new Error('Expected a Test262Error, but a "' + err.constructor.name + '" was thrown.');
+  }
+}
+
+if (!threw) {
+  throw new Error('Expected a Test262Error, but no error was thrown.');
+}
+
+reportCompare(0, 0);