worker: enable transferring WASM modules

Enable in-memory transfer of WASM modules without recompilation.

Previously, the serialization step worked, but deserialization failed
because we did not explicitly enable decoding inline WASM modules,
and so the message was not successfully received.

PR-URL: https://github.com/nodejs/node/pull/25314
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

2 files changed, 29 insertions, 2 deletions

diff --git a/test/parallel/test-worker-message-port-wasm-module.js b/test/parallel/test-worker-message-port-wasm-module.js
new file mode 100644
index 0000000000..43c12a8519
--- /dev/null
+++ b/test/parallel/test-worker-message-port-wasm-module.js
@@ -0,0 +1,19 @@
+// Flags: --experimental-worker
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const fixtures = require('../common/fixtures');
+
+const { Worker } = require('worker_threads');
+const wasmModule = new WebAssembly.Module(fixtures.readSync('test.wasm'));
+
+const worker = new Worker(`
+const { parentPort } = require('worker_threads');
+parentPort.once('message', ({ wasmModule }) => {
+  const instance = new WebAssembly.Instance(wasmModule);
+  parentPort.postMessage(instance.exports.addTwo(10, 20));
+});
+`, { eval: true });
+
+worker.once('message', common.mustCall((num) => assert.strictEqual(num, 30)));
+worker.postMessage({ wasmModule });
diff --git a/test/parallel/test-worker-message-port-wasm-threads.js b/test/parallel/test-worker-message-port-wasm-threads.js
index 6d4f21d728..891da80e30 100644
--- a/test/parallel/test-worker-message-port-wasm-threads.js
+++ b/test/parallel/test-worker-message-port-wasm-threads.js
@@ -32,15 +32,23 @@ assert(buffer instanceof SharedArrayBuffer);
   // stopped when we exit.
   const worker = new Worker(`
   const { parentPort } = require('worker_threads');
+
+  // Compile the same WASM module from its source bytes.
   const wasmSource = new Uint8Array([${wasmSource.join(',')}]);
   const wasmModule = new WebAssembly.Module(wasmSource);
   const instance = new WebAssembly.Instance(wasmModule);
   parentPort.postMessage(instance.exports.memory);
+
+  // Do the same thing, except we receive the WASM module via transfer.
+  parentPort.once('message', ({ wasmModule }) => {
+    const instance = new WebAssembly.Instance(wasmModule);
+    parentPort.postMessage(instance.exports.memory);
+  });
   `, { eval: true });
-  worker.once('message', common.mustCall(({ buffer }) => {
+  worker.on('message', common.mustCall(({ buffer }) => {
     assert(buffer instanceof SharedArrayBuffer);
     worker.buf = buffer; // Basically just keep the reference to buffer alive.
-  }));
+  }, 2));
   worker.once('exit', common.mustCall());
   worker.postMessage({ wasmModule });
 }