add test case for moving modules and chunks between runtimes

test/helpers/createFakeWorker.js

@@ -62,14 +62,20 @@ require(${JSON.stringify(path.resolve(outputDirectory, file))});
 			this.worker = new (require("worker_threads").Worker)(workerBootstrap, {
 				eval: true
 			});
+
+			this._onmessage = undefined;
 		}
 
 		set onmessage(value) {
-			this.worker.on("message", data => {
-				value({
-					data
-				});
-			});
+			if (this._onmessage) this.worker.off("message", this._onmessage);
+			this.worker.on(
+				"message",
+				(this._onmessage = data => {
+					value({
+						data
+					});
+				})
+			);
 		}
 
 		postMessage(data) {

test/hotCases/worker/move-between-runtime/chunk.js

@@ -0,0 +1 @@
+export default "chunk";

test/hotCases/worker/move-between-runtime/chunkS.js

@@ -0,0 +1 @@
+export default "chunkS";

test/hotCases/worker/move-between-runtime/index.js

@@ -0,0 +1,33 @@
+const update = () =>
+	new Promise((resolve, reject) => {
+		NEXT(err => {
+			if (err) reject(err);
+			else resolve();
+		});
+	});
+
+const expectMessage = (w, msg) =>
+	new Promise((resolve, reject) => {
+		w.onmessage = ({ data }) => {
+			if (data === msg) resolve();
+			else reject(new Error(data));
+		};
+	});
+
+const next = w => {
+	const p = expectMessage(w, "next");
+	w.postMessage("next");
+	return p;
+};
+
+it("should support hot module replacement in WebWorkers", async () => {
+	const a = new Worker(new URL("workerA.js", import.meta.url));
+	const b = new Worker(new URL("workerB.js", import.meta.url));
+	for (let i = 0; i < 7; i++) {
+		await update();
+		await next(a);
+		await next(b);
+	}
+	await a.terminate();
+	await b.terminate();
+});

test/hotCases/worker/move-between-runtime/module.js

@@ -0,0 +1 @@
+export default "module";

test/hotCases/worker/move-between-runtime/moduleA.js

@@ -0,0 +1,19 @@
+export default 0;
+---
+export default 1;
+import "./module";
+---
+export default 2;
+import "./module";
+---
+export default 3;
+---
+export default 4;
+if (Math.random() < 0) import("./chunk");
+---
+export default 5;
+if (Math.random() < 0) import("./chunk");
+---
+export default 6;
+---
+export default 7;

test/hotCases/worker/move-between-runtime/moduleAs.js

@@ -0,0 +1,19 @@
+export default 0;
+---
+export default 1;
+import "./moduleS";
+---
+export default 2;
+import "./moduleS";
+---
+export default 3;
+---
+export default 4;
+if (Math.random() < 0) import("./chunkS");
+---
+export default 5;
+if (Math.random() < 0) import("./chunkS");
+---
+export default 6;
+---
+export default 7;

test/hotCases/worker/move-between-runtime/moduleB.js

@@ -0,0 +1,19 @@
+export default 0;
+---
+export default 1;
+---
+export default 2;
+import "./module";
+---
+export default 3;
+import "./module";
+---
+export default 4;
+---
+export default 5;
+if (Math.random() < 0) import("./chunk");
+---
+export default 6;
+if (Math.random() < 0) import("./chunk");
+---
+export default 7;

test/hotCases/worker/move-between-runtime/moduleBs.js

@@ -0,0 +1,19 @@
+export default 0;
+---
+export default 1;
+---
+export default 2;
+import "./moduleS";
+---
+export default 3;
+import "./moduleS";
+---
+export default 4;
+---
+export default 5;
+if (Math.random() < 0) import("./chunkS");
+---
+export default 6;
+if (Math.random() < 0) import("./chunkS");
+---
+export default 7;

test/hotCases/worker/move-between-runtime/moduleS.js

@@ -0,0 +1 @@
+export default "moduleS";

test/hotCases/worker/move-between-runtime/test.filter.js

@@ -0,0 +1,5 @@
+var supportsWorker = require("../../../helpers/supportsWorker");
+
+module.exports = function (config) {
+	return supportsWorker();
+};

test/hotCases/worker/move-between-runtime/worker.js

@@ -0,0 +1,18 @@
+export default fn => {
+	self.onmessage = async ({ data: msg }) => {
+		try {
+			switch (msg) {
+				case "next":
+					if (!(await import.meta.webpackHot.check(true)))
+						throw new Error("No update found");
+					await fn();
+					self.postMessage("next");
+					break;
+				default:
+					throw new Error("Unexpected message");
+			}
+		} catch (e) {
+			self.postMessage("error: " + e.stack);
+		}
+	};
+};

test/hotCases/worker/move-between-runtime/workerA.js

@@ -0,0 +1,5 @@
+import worker from "./worker";
+import "./moduleA";
+worker(() => import(/* webpackChunkName: "shared" */ "./moduleAs"));
+import.meta.webpackHot.accept("./moduleA");
+import.meta.webpackHot.accept("./moduleAs");

test/hotCases/worker/move-between-runtime/workerB.js

@@ -0,0 +1,5 @@
+import worker from "./worker";
+import "./moduleB";
+worker(() => import(/* webpackChunkName: "shared" */ "./moduleBs"));
+import.meta.webpackHot.accept("./moduleB");
+import.meta.webpackHot.accept("./moduleBs");