1 files changed, 19 insertions, 0 deletions
diff --git a/testing/web-platform/tests/wasm/jsapi/instance/toString.any.js b/testing/web-platform/tests/wasm/jsapi/instance/toString.any.js
new file mode 100644
index 0000000000..547a9ca829
--- /dev/null
+++ b/testing/web-platform/tests/wasm/jsapi/instance/toString.any.js
@@ -0,0 +1,19 @@
+// META: global=window,dedicatedworker,jsshell
+// META: script=/wasm/jsapi/wasm-module-builder.js
+
+test(() => {
+  const emptyModuleBinary = new WasmModuleBuilder().toBuffer();
+  const module = new WebAssembly.Module(emptyModuleBinary);
+  const instance = new WebAssembly.Instance(module);
+  assert_class_string(instance, "WebAssembly.Instance");
+}, "Object.prototype.toString on an Instance");
+
+test(() => {
+  assert_own_property(WebAssembly.Instance.prototype, Symbol.toStringTag);
+
+  const propDesc = Object.getOwnPropertyDescriptor(WebAssembly.Instance.prototype, Symbol.toStringTag);
+  assert_equals(propDesc.value, "WebAssembly.Instance", "value");
+  assert_equals(propDesc.configurable, true, "configurable");
+  assert_equals(propDesc.enumerable, false, "enumerable");
+  assert_equals(propDesc.writable, false, "writable");
+}, "@@toStringTag exists on the prototype with the appropriate descriptor");