Running tests with a fresh bootstrapped app yields error

[madflow]

Describe the bug

When runnning test in a newly bootstrapped app, I get:

 Error when evaluating SSR module /node_modules/@sveltejs/kit/src/runtime/server/index.js: Cannot read properties of undefined (reading 'wrapDynamicImport')

The tests still run and pass.

Reproduction

npx sv create broken
[y] Svelte library (setup with svelte-package to help correctly package your library)
[y] Yes, using TypeScript syntax
What would you like to add to your project? (use arrow keys / space bar)
│  ◼ prettier (formatter - https://prettier.io)
│  ◼ eslint (linter - https://eslint.org)
│  ◼ vitest (unit testing - https://vitest.dev)
│  ◼ playwright (browser testing - https://playwright.dev)
vitest: What do you want to use vitest for?
│  ◼ unit testing
│  ◼ component testing
Which package manager do you want to install dependencies with?
│  ○ None
│  ● npm

cd broken && npm i

npm run test:unit

broken@0.0.1 test:unit
vitest

DEV v3.2.4 /private/tmp/broken

The following Vite config options will be overridden by SvelteKit:

• base
  ✓ server src/demo.spec.ts (1 test) 1ms
  12:14:50 PM [vite] (ssr) Error when evaluating SSR module /node_modules/@sveltejs/kit/src/runtime/server/index.js: Cannot read properties of undefined (reading 'wrapDynamicImport')
  at /private/tmp/broken/node_modules/@sveltejs/kit/src/runtime/app/server/event.js:9:1
  at ESModulesEvaluator.runInlinedModule (file:///private/tmp/broken/node_modules/vite/dist/node/module-runner.js:909:9)
  at SSRCompatModuleRunner.directRequest (file:///private/tmp/broken/node_modules/vite/dist/node/module-runner.js:1067:80)
  at SSRCompatModuleRunner.directRequest (file:///private/tmp/broken/node_modules/vite/dist/node/chunks/dep-BHkUv4Z8.js:18888:34)
  at SSRCompatModuleRunner.cachedRequest (file:///private/tmp/broken/node_modules/vite/dist/node/module-runner.js:973:23)
  at request (file:///private/tmp/broken/node_modules/vite/dist/node/module-runner.js:1014:76)
  at async eval (/private/tmp/broken/node_modules/@sveltejs/kit/src/runtime/server/endpoint.js:4:1)
  at async ESModulesEvaluator.runInlinedModule (file:///private/tmp/broken/node_modules/vite/dist/node/module-runner.js:909:3)
  at async SSRCompatModuleRunner.directRequest (file:///private/tmp/broken/node_modules/vite/dist/node/module-runner.js:1067:59)
  at async SSRCompatModuleRunner.directRequest (file:///private/tmp/broken/node_modules/vite/dist/node/chunks/dep-BHkUv4Z8.js:18888:22)
  ✓ client (chromium) src/routes/page.svelte.test.ts (1 test) 3ms

Test Files 2 passed (2)
Tests 2 passed (2)
Start at 12:14:49
Duration 1.39s (transform 19ms, setup 8ms, collect 95ms, tests 4ms, environment 0ms, prepare 1.58s)

### Logs

```Shell

System Info

node -v v22.14.0
npm --version 11.3.0

system_profiler SPSoftwareDataType SPHardwareDataType
Software:
    System Software Overview:

      System Version: macOS 15.5 (24F74)
      Kernel Version: Darwin 24.5.0

Hardware:

    Hardware Overview:

      Model Name: MacBook Pro
      Model Identifier: Mac16,1
      Model Number: MW2U3D/A
      Chip: Apple M4
      Total Number of Cores: 10 (4 performance and 6 efficiency)
      Memory: 16 GB
      System Firmware Version: 11881.121.1
      OS Loader Version: 11881.121.1

Severity

annoyance

Additional Information

No response

[ptrxyz]

I also ran into this. Can anyone shed some light into it and whats broken here? I don't even have an idea where to start ... :/

[madflow]

My guess is, that it is somewhere buried in the usage of vitest.

rg -u wrapDynamicImport

node_modules/@vitest/mocker/dist/node.js
407:                    const replaceString = `globalThis[${globalThisAccessor}].wrapDynamicImport(() => import(`;

node_modules/@vitest/mocker/dist/mocker.d-Ce9_ySj5.d.ts
56:     wrapDynamicImport<T>(moduleFactory: () => Promise<T>): Promise<T>;

node_modules/@vitest/mocker/dist/chunk-mocker.js
1472:           return this.wrapDynamicImport(() => import(
1573:   wrapDynamicImport(moduleFactory) {

node_modules/@vitest/browser/dist/client/__vitest_browser__/tester-BYDMHqQ9.js
3201:    return this.wrapDynamicImport(() => import(
3299:  wrapDynamicImport(moduleFactory) {
3331:  wrapDynamicImport(moduleFactory) {

node_modules/@vitest/browser/dist/client/esm-client-injector.js
21:    wrapDynamicImport: wrapModule,

node_modules/@vitest/browser/dist/index.js
875:                                    s.prepend("globalThis.__vitest_browser_runner__ = { wrapDynamicImport: f => f() };\n");

[nattarus]

for now disable vitest browser ui config seem to make this error go away ( or enable headless work too )
in vite.config.ts

				test: {
					name: 'client',
					environment: 'browser',
					browser: {
						enabled: true,
						provider: 'playwright',
						instances: [{ browser: 'chromium' }],
						// headless: true,
						ui: false
					},
					include: ['src/**/*.svelte.{test,spec}.{js,ts}'],
					exclude: ['src/lib/server/**'],
					setupFiles: ['./vitest-setup-client.ts']
				}

[eallenOP]

for now disable vitest browser ui config seem to make this error go away ( or enable headless work too ) in vite.config.ts

This (enable headless) worked for me in getting rid of the SSR error but I still get:

The following Vite config options will be overridden by SvelteKit:

- base

There is no config option with that name in vite.config.ts.

[oluijks]

I just ran into this issue as well, adding ui: false makes the error go away. Could this be a vitest issue?

[idleberg]

Setting ui: false worked for a colleague, but not for me.

We settled on this alternative workaround:

// svelte.config.js

const isTest = typeof process.env.VITEST !== 'undefined';

const config = {
	paths: {
		// ignore base path for tests
		base: isTest ? undefined : '/my-base-path',
	},
};

export default config;

[madflow]

So I did a re-retest, and with a fresh "npx sv create" I was not able to replicate the problem. I do not see any linked issues or PR I can pin this to. I would close this issue, not sure though.

[oluijks]

Perhaps this is related, after updateing the test script, no more error for me:

sveltejs/svelte#16663