1 files changed, 41 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/debug/onNewScript-wasm-02.js b/js/src/jit-test/tests/debug/onNewScript-wasm-02.js
new file mode 100644
index 0000000000..3586fe4c2e
--- /dev/null
+++ b/js/src/jit-test/tests/debug/onNewScript-wasm-02.js
@@ -0,0 +1,41 @@
+// |jit-test| skip-if: !wasmDebuggingEnabled()
+// Draining the job queue from an onNewScript hook reporting a streamed wasm
+// module should not deadlock.
+
+ignoreUnhandledRejections();
+
+try {
+    WebAssembly.compileStreaming();
+    // Avoid mixing the test's jobs with the debuggee's, so that
+    // automated checks can make sure AutoSaveJobQueue only
+    // suspends debuggee work.
+    drainJobQueue();
+} catch (err) {
+    assertEq(String(err).indexOf("not supported with --no-threads") !== -1, true);
+    quit();
+}
+
+var g = newGlobal({newCompartment: true});
+
+var source = new g.Uint8Array(wasmTextToBinary('(module (func unreachable))'));
+g.source = source;
+
+var dbg = new Debugger(g);
+dbg.allowWasmBinarySource = true;
+dbg.onNewScript = function (s, g) {
+  drainJobQueue();
+};
+
+// For the old code to deadlock, OffThreadPromiseRuntimeState::internalDrain
+// needs to get two Dispatchables at once when it swaps queues. A call to
+// instantiateStreaming enqueues a job that will kick off a helper thread, so to
+// make sure that two helper threads have had time to complete and enqueue their
+// Dispatchables, we put a delay in the job queue after the helper thread
+// launches.
+g.eval(`
+  WebAssembly.instantiateStreaming(source);
+  WebAssembly.instantiateStreaming(source);
+  Promise.resolve().then(() => sleep(0.1));
+`);
+
+drainJobQueue();