fix: dispose Cloudflare platform proxy when Vite servers close

.changeset/calm-proxies-close.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/adapter-cloudflare': patch
+---
+
+fix: dispose the development platform proxy when Vite servers close

packages/adapter-cloudflare/index.js

@@ -222,13 +222,26 @@ export default function (options = {}) {
  * @returns {Plugin}
  */
 function virtual_workers_module(options, stub_import) {
-	const setup = async () => {
+	/** @param {import('vite').ViteDevServer | import('vite').PreviewServer} server */
+	const setup = async (server) => {
 		if (globalThis.__sveltekit_cloudflare_platform) return;
 		const proxy = await getPlatformProxy(options);
 		// We store the platform proxy on globalThis so that our virtual workers module
 		// can access the same instance that we use here to populate `caches` and `cf` (above).
 		globalThis.__sveltekit_cloudflare_platform = proxy;
 		/** @type {any} */ (globalThis).caches = proxy.caches;
+
+		const close = server.close.bind(server);
+		/** @type {Promise<void> | undefined} */
+		let disposing;
+		server.close = async () => {
+			disposing ??= proxy.dispose().finally(() => {
+				if (globalThis.__sveltekit_cloudflare_platform === proxy) {
+					Reflect.deleteProperty(globalThis, '__sveltekit_cloudflare_platform');
+				}
+			});
+			await Promise.all([close(), disposing]);
+		};
 	};
 	return {
 		name: 'vite-plugin-sveltekit-adapter-cloudflare-virtual-workers-module',

packages/adapter-cloudflare/index.spec.js

@@ -0,0 +1,76 @@
+import { afterEach, expect, test, vi } from 'vitest';
+import { createServer } from 'vite';
+
+const dispose = vi.fn(async () => {});
+
+vi.mock('wrangler', () => ({
+	getPlatformProxy: vi.fn(() =>
+		Promise.resolve({
+			caches: {},
+			dispose
+		})
+	),
+	unstable_readConfig: vi.fn()
+}));
+
+const { default: adapter } = await import('./index.js');
+
+const get_plugin = () =>
+	/** @type {import('vite').Plugin} */ (/** @type {any} */ (adapter().vite).plugins[0]);
+
+afterEach(() => {
+	Reflect.deleteProperty(globalThis, '__sveltekit_cloudflare_platform');
+	dispose.mockClear();
+});
+
+test('disposes the platform proxy when the Vite dev server closes', async () => {
+	const server = await createServer({
+		configFile: false,
+		logLevel: 'silent',
+		plugins: [get_plugin()],
+		server: { middlewareMode: true }
+	});
+
+	expect(globalThis.__sveltekit_cloudflare_platform).toBeDefined();
+
+	await server.close();
+	await server.close();
+
+	expect(dispose).toHaveBeenCalledOnce();
+	expect(globalThis.__sveltekit_cloudflare_platform).toBeUndefined();
+});
+
+test('disposes the platform proxy when the Vite preview server closes', async () => {
+	const plugin = get_plugin();
+	const close = vi.fn();
+	const server = { close };
+
+	await /** @type {Function} */ (plugin.configurePreviewServer)(server);
+	await server.close();
+
+	expect(close).toHaveBeenCalledOnce();
+	expect(dispose).toHaveBeenCalledOnce();
+	expect(globalThis.__sveltekit_cloudflare_platform).toBeUndefined();
+});
+
+test('closes concurrently and does not clear a replacement platform proxy', async () => {
+	const plugin = get_plugin();
+	const close = vi.fn();
+	const server = { close };
+	/** @type {PromiseWithResolvers<void>} */
+	const disposal = Promise.withResolvers();
+	dispose.mockImplementationOnce(() => disposal.promise);
+
+	await /** @type {Function} */ (plugin.configurePreviewServer)(server);
+	const closing = server.close();
+
+	expect(close).toHaveBeenCalledOnce();
+	expect(dispose).toHaveBeenCalledOnce();
+
+	const replacement = /** @type {import('wrangler').PlatformProxy} */ ({});
+	globalThis.__sveltekit_cloudflare_platform = replacement;
+	disposal.resolve();
+	await closing;
+
+	expect(globalThis.__sveltekit_cloudflare_platform).toBe(replacement);
+});

packages/adapter-cloudflare/tsconfig.json

@@ -17,6 +17,7 @@
 	},
 	"include": [
 		"index.js",
+		"index.spec.js",
 		"src",
 		"utils.js",
 		"utils.spec.js",