feat(vitest-pool-workers): add vite pre-bundling support

Author: edmundhung

fixtures/vitest-pool-workers-examples/external-package-resolution/src/index.ts

@@ -1,4 +1,10 @@
 import { Toucan } from "toucan-js";
+// Test pre-bundling dependency relies on exports field without a default entrypoint
+// @see https://github.com/cloudflare/workers-sdk/issues/6591
+import "discord-api-types/v10";
+// Test pre-bundling dependencies with browser field mapping
+// @see https://github.com/cloudflare/workers-sdk/issues/6581
+import "@microlabs/otel-cf-workers";
 
 export default {
 	async fetch(): Promise<Response> {

fixtures/vitest-pool-workers-examples/external-package-resolution/vitest.config.ts

@@ -2,6 +2,14 @@ import { defineWorkersProject } from "@cloudflare/vitest-pool-workers/config";
 
 export default defineWorkersProject({
 	test: {
+		deps: {
+			optimizer: {
+				ssr: {
+					enabled: true,
+					include: ["discord-api-types/v10", "@microlabs/otel-cf-workers"],
+				},
+			},
+		},
 		poolOptions: {
 			workers: {
 				wrangler: { configPath: "./wrangler.toml" },

fixtures/vitest-pool-workers-examples/package.json

@@ -13,13 +13,16 @@
 	"devDependencies": {
 		"@cloudflare/vitest-pool-workers": "workspace:*",
 		"@cloudflare/workers-types": "^4.20250204.0",
+		"@microlabs/otel-cf-workers": "1.0.0-rc.45",
 		"@types/node": "catalog:default",
+		"discord-api-types": "0.37.98",
 		"ext-dep": "file:./internal-module-resolution/vendor/ext-dep",
 		"jose": "^5.2.2",
 		"miniflare": "workspace:*",
 		"run-script-os": "^1.1.6",
-		"toucan-js": "^3.3.1",
+		"toucan-js": "3.4.0",
 		"typescript": "catalog:default",
+		"vite": "catalog:default",
 		"vitest": "catalog:default",
 		"wrangler": "workspace:*"
 	},

package.json

@@ -49,7 +49,7 @@
 		"tree-kill": "^1.2.2",
 		"turbo": "^2.2.3",
 		"typescript": "catalog:default",
-		"vite": "^5.0.12",
+		"vite": "catalog:default",
 		"vitest": "catalog:default"
 	},
 	"packageManager": "[email protected]",

packages/vitest-pool-workers/src/config/index.ts

@@ -1,6 +1,7 @@
 import assert from "node:assert";
 import crypto from "node:crypto";
 import fs from "node:fs/promises";
+import { builtinModules } from "node:module";
 import path from "node:path";
 import { MessageChannel, receiveMessageOnPort } from "node:worker_threads";
 import type {
@@ -110,6 +111,13 @@ function ensureArrayExcludes<T>(array: T[], items: T[]) {
 const requiredConditions = ["workerd", "worker", "browser"];
 const requiredMainFields = ["browser", "module", "jsnext:main", "jsnext"];
 
+const cloudflareBuiltInModules = [
+	"cloudflare:email",
+	"cloudflare:sockets",
+	"cloudflare:workers",
+	"cloudflare:workflows",
+];
+
 function createConfigPlugin(): Plugin<WorkersConfigPluginAPI> {
 	// Use a unique ID for each `cloudflare:test` module so updates in one `main`
 	// don't trigger re-runs in all other projects, just the one that changed.
@@ -147,6 +155,17 @@ function createConfigPlugin(): Plugin<WorkersConfigPluginAPI> {
 			// https://github.com/vitejs/vite/blob/v5.1.4/packages/vite/src/node/plugins/resolve.ts#L175
 			config.ssr.target = "webworker";
 
+			// Pre-bundling dependencies with vite
+			config.test.deps ??= {};
+			config.test.deps.optimizer ??= {};
+			config.test.deps.optimizer.ssr ??= {};
+			config.test.deps.optimizer.ssr.enabled ??= true;
+			config.test.deps.optimizer.ssr.exclude ??= [];
+			ensureArrayIncludes(config.test.deps.optimizer.ssr.exclude, [
+				...cloudflareBuiltInModules,
+				...builtinModules.concat(builtinModules.map((m) => `node:${m}`)),
+			]);
+
 			// Ideally, we would force `pool` to be @cloudflare/vitest-pool-workers here,
 			// but the tests in `packages/vitest-pool-workers` define `pool` as "../..".
 			config.test.pool ??= "@cloudflare/vitest-pool-workers";

packages/vitest-pool-workers/src/pool/module-fallback.ts

@@ -41,6 +41,19 @@ function trimSuffix(suffix: string, value: string) {
 	return value.substring(0, value.length - suffix.length);
 }
 
+/**
+ * When pre-bundling is enabled, Vite will add a hash to the end of the file path
+ * e.g. `/node_modules/.vite/deps/my-dep.js?v=f3sf2ebd`
+ *
+ * @see https://vite.dev/guide/features.html#npm-dependency-resolving-and-pre-bundling
+ * @see https://github.com/cloudflare/workers-sdk/pull/5673
+ */
+const versionHashRegExp = /\?v=[0-9a-f]+$/;
+
+function trimViteVersionHash(filePath: string) {
+	return filePath.replace(versionHashRegExp, "");
+}
+
 // RegExp for path suffix to force loading module as specific type.
 // (e.g. `/path/to/module.wasm?mf_vitest_force=CompiledWasm`)
 // This suffix will be added by the pool when fetching a module that matches a
@@ -323,7 +336,8 @@ async function viteResolve(
 		//       (Specifically, the "tinyrainbow" module imports `node:tty` as `tty`)
 		return id;
 	}
-	return resolved.id;
+
+	return trimViteVersionHash(resolved.id);
 }
 
 type ResolveMethod = "import" | "require";

packages/workers-editor-shared/package.json

@@ -42,7 +42,7 @@
 		"eslint": "^8.49.0",
 		"react": "^18.3.1",
 		"react-dom": "^18.3.1",
-		"vite": "^5.0.12",
+		"vite": "catalog:default",
 		"vite-plugin-dts": "^4.0.1"
 	},
 	"peerDependencies": {