compat: support --compat in web workers (#13629)

Adds another callback to WebWorkerOptions that allows to execute
some modules before actual worker code executes. This allows to set up Node
global using std/node.

1 files changed, 18 insertions, 0 deletions

diff --git a/cli/tests/testdata/compat/worker/worker_test.mjs b/cli/tests/testdata/compat/worker/worker_test.mjs
new file mode 100644
index 000000000..215605487
--- /dev/null
+++ b/cli/tests/testdata/compat/worker/worker_test.mjs
@@ -0,0 +1,18 @@
+import { deferred } from "../../../../../test_util/std/async/deferred.ts";
+
+const promise = deferred();
+const url = new URL("./worker.mjs", import.meta.url);
+const worker = new Worker(url.href, { type: "module", deno: true });
+
+worker.onmessage = (e) => {
+    const pid = e.data.pid;
+    if (typeof pid != "number") {
+        throw new Error("pid is not a number");
+    }
+    console.log("process.pid from worker:", pid);
+    promise.resolve();
+};
+
+worker.postMessage("hello");
+await promise;
+worker.terminate();