From a179cf23bebb09a19deb93a3386f6b047ae65ae3 Mon Sep 17 00:00:00 2001
From: Ms2ger <Ms2ger@igalia.com>
Date: Mon, 29 Sep 2025 14:53:42 +0200
Subject: [PATCH] Add assert_exception to the core test harnesses

---
 test/harness/async_index.js | 22 +++++++++++++++++++++-
 test/harness/sync_index.js  | 10 ++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/test/harness/async_index.js b/test/harness/async_index.js
index 7b4fcd1ae4..94de545dd5 100644
--- a/test/harness/async_index.js
+++ b/test/harness/async_index.js
@@ -281,6 +281,26 @@ function assert_trap(action, source) {
     .catch(_ => {});
 }
 
+function assert_exception(action, source) {
+  const test = `Test that a WebAssembly code throws an exception (${source})`;
+  const loc = new Error().stack.toString().replace("Error", "");
+  chain = Promise.all([chain, action()])
+    .then(
+      result => {
+        uniqueTest(_ => {
+          assert_true(false, loc);
+        }, test);
+      },
+      error => {
+        uniqueTest(_ => {
+          // Pass
+        }, test);
+      }
+    )
+    // Clear all exceptions, so that subsequent tests get executed.
+    .catch(_ => {});
+}
+
 function assert_return(action, source, ...expected) {
   const test = `Test that a WebAssembly code returns a specific result (${source})`;
   const loc = new Error().stack.toString().replace("Error", "");
@@ -355,7 +375,7 @@ try {
 }
 
 function assert_exhaustion(action) {
-  const test = "Test that a WebAssembly code exhauts the stack space";
+  const test = "Test that a WebAssembly code exhausts the stack space";
   const loc = new Error().stack.toString().replace("Error", "");
   chain = Promise.all([action(), chain])
     .then(
diff --git a/test/harness/sync_index.js b/test/harness/sync_index.js
index 77f601f590..a984be4964 100644
--- a/test/harness/sync_index.js
+++ b/test/harness/sync_index.js
@@ -339,6 +339,16 @@ function assert_trap(action, source) {
     }, `A wast module that must trap at runtime. (${source})`);
 }
 
+function assert_exception(action, source) {
+    let result = action();
+
+    _assert(result instanceof Result);
+
+    uniqueTest(() => {
+        assert_true(result.isError(), 'expected error result');
+    }, `A wast module that must throw an exception at runtime. (${source})`);
+}
+
 let StackOverflow;
 try { (function f() { 1 + f() })() } catch (e) { StackOverflow = e.constructor }