Vitest shows provider as undefined for browsers even though provided in config

[NaviTheCoderboi]

Describe the bug

When use vitest browser mode, it gives such error even i have provided correct config as mentioned in docs - https://main.vitest.dev/guide/browser/#configuration

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Unhandled Errors ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯

Vitest caught 1 unhandled error during the test run.
This might cause false positive tests. Resolve unhandled errors to make sure your tests 
are not affected.

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Unhandled Error ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
TypeError: Cannot read properties of undefined (reading 'provider')
 ❯ executeTests node_modules/.pnpm/@vitest+browser@3.0.2_@types+node@22.10.6_playwright@1.49.1_typescript@5.7.3_vite@6.0.7_@type_do4ccanmhzjdyssuzidjwadwgi/node_modules/@vitest/browser/dist/index.js:2997:30
 ❯ runWorkspaceTests node_modules/.pnpm/@vitest+browser@3.0.2_@types+node@22.10.6_playwright@1.49.1_typescript@5.7.3_vite@6.0.7_@type_do4ccanmhzjdyssuzidjwadwgi/node_modules/@vitest/browser/dist/index.js:3083:13
 ❯ executeTests node_modules/.pnpm/vitest@3.0.2_@types+node@22.10.6_@vitest+browser@3.0.2_happy-dom@16.5.3_msw@2.7.0_@types+node@22.10.6_typescript@5.7.3_/node_modules/vitest/dist/chunks/resolveConfig.DATSOo7x.js:7720:5
 ❯ node_modules/.pnpm/vitest@3.0.2_@types+node@22.10.6_@vitest+browser@3.0.2_happy-dom@16.5.3_msw@2.7.0_@types+node@22.10.6_typescript@5.7.3_/node_modules/vitest/dist/chunks/cli-api.B7hOUwun.js:12524:11

my config

import { svelte } from '@sveltejs/vite-plugin-svelte';
import { configDefaults, defineConfig } from 'vitest/config';

export default defineConfig({
    plugins: [svelte()],
    cacheDir: './.cache/vitest',
    test: {
        exclude: configDefaults.exclude,
        workspace: [
            {
                test: {
                    // include: ['packages/**/*.@(svelte.)test.ts'],
                    name: 'browser',
                    browser: {
                        provider: 'playwright',
                        enabled: true,
                        instances: [
                            {
                                browser: 'chromium'
                            }
                        ]
                    }
                }
            }
        ]
    }
});

Reproduction

https://github.com/NaviTheCoderboi/vitest-repro

System Info

System:
    OS: Windows 10 10.0.19045
    CPU: (4) x64 Intel(R) Core(TM) i5-6500T CPU @ 2.50GHz  
    Memory: 2.05 GB / 7.88 GB
  Binaries:
    Node: 23.2.0 - ~\scoop\apps\nodejs\current\node.EXE    
    npm: 10.9.0 - ~\scoop\apps\nodejs\current\npm.CMD      
    pnpm: 9.15.2 - ~\scoop\apps\nodejs\current\bin\pnpm.CMD
    bun: 1.1.34 - ~\scoop\shims\bun.EXE
  Browsers:
    Edge: Chromium (117.0.2045.31)
    Internet Explorer: 11.0.19041.3636
  npmPackages:
    @vitest/browser: ^3.0.2 => 3.0.2 
    vitest: ^3.0.2 => 3.0.2

Used Package Manager

pnpm

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

[ranisalt]

I am having the same issue and it started with v3.0.0 (v3.0.1 also has the same problem). It is working as expected with v2.1.8, I suppose this issue was introduced with the changed configuration structure from name to instances

[jfairley]

I noticed that running my entire suite works. It's only when I call out my browser workspace that it fails.

This led to find that excluding the other workspaces works. 🤯

For me, that's --project !unit.

[NaviTheCoderboi]

I noticed that running my entire suite works. It's only when I call out my browser workspace that it fails.

This led to find that excluding the other workspaces works. 🤯

For me, that's --project !unit.

I have only browser tests , so I can't exclude them , 😂

[hatai]

I am having the same issue...

Error logs

❯ pnpm run test:component

> [email protected] test:component /Users/taigen.hamada/projects/icare/vue3/app/frontend
> vitest --project component

WARN No story files found for the specified pattern: pages/**/*.stories.ts

 DEV  v3.0.3 /Users/taigen.hamada/projects/icare/vue3/app/frontend

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Vitest caught 1 unhandled error during the test run.
This might cause false positive tests. Resolve unhandled errors to make sure your tests are not affected.

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ Unhandled Error ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
TypeError: Cannot read properties of undefined (reading 'provider')
 ❯ getThreadsCount ../../node_modules/.pnpm/@[email protected]_@[email protected][email protected][email protected][email protected]_@ty_rsjsyalurh3tlejngvzgbhp4yi/node_modules/@vitest/browser/dist/index.js:3089:46
 ❯ executeTests ../../node_modules/.pnpm/@[email protected]_@[email protected][email protected][email protected][email protected]_@ty_rsjsyalurh3tlejngvzgbhp4yi/node_modules/@vitest/browser/dist/index.js:2996:26
 ❯ runWorkspaceTests ../../node_modules/.pnpm/@[email protected]_@[email protected][email protected][email protected][email protected]_@ty_rsjsyalurh3tlejngvzgbhp4yi/node_modules/@vitest/browser/dist/index.js:3083:13
 ❯ executeTests ../../node_modules/.pnpm/[email protected]_@[email protected]_@[email protected][email protected][email protected]_jsdom@25._wa7qawb64or6limf5r55rud6za/node_modules/vitest/dist/chunks/resolveConfig.9CnFfuqj.js:7720:5
 ❯ ../../node_modules/.pnpm/[email protected]_@[email protected]_@[email protected][email protected][email protected]_jsdom@25._wa7qawb64or6limf5r55rud6za/node_modules/vitest/dist/chunks/cli-api.BaY17YBo.js:12524:11
 ❯ Vitest.runFiles ../../node_modules/.pnpm/[email protected]_@[email protected]_@[email protected][email protected][email protected]_jsdom@25._wa7qawb64or6limf5r55rud6za/node_modules/vitest/dist/chunks/cli-api.BaY17YBo.js:12551:12
 ❯ Vitest.start ../../node_modules/.pnpm/[email protected]_@[email protected]_@[email protected][email protected][email protected]_jsdom@25._wa7qawb64or6limf5r55rud6za/node_modules/vitest/dist/chunks/cli-api.BaY17YBo.js:12431:21
 ❯ startVitest ../../node_modules/.pnpm/[email protected]_@[email protected]_@[email protected][email protected][email protected]_jsdom@25._wa7qawb64or6limf5r55rud6za/node_modules/vitest/dist/chunks/cli-api.BaY17YBo.js:13563:7
 ❯ start ../../node_modules/.pnpm/[email protected]_@[email protected]_@[email protected][email protected][email protected]_jsdom@25._wa7qawb64or6limf5r55rud6za/node_modules/vitest/dist/chunks/cac.Cfe6a4o8.js:1571:17

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 Test Files   (1)
      Tests  no tests
     Errors  1 error
   Start at  18:27:57
   Duration  4.57s (transform 0ms, setup 0ms, collect 0ms, tests 0ms, environment 0ms, prepare 0ms)

System Info

  System:
    OS: macOS 15.2
    CPU: (8) arm64 Apple M3
    Memory: 111.20 MB / 24.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 18.20.2 - ~/.local/share/mise/installs/node/18.20.2/bin/node
    npm: 10.5.0 - ~/.local/share/mise/installs/node/18.20.2/bin/npm
    pnpm: 9.15.1 - ~/.local/share/mise/installs/node/18.20.2/bin/pnpm
  Browsers:
    Chrome: 131.0.6778.265
    Edge: 132.0.2957.115
    Safari: 18.2
  npmPackages:
    @vitejs/plugin-legacy: ^6.0.0 => 6.0.0 
    @vitejs/plugin-vue: ^5.2.1 => 5.2.1 
    @vitest/browser: ^3.0.3 => 3.0.3 
    vite: ^6.0.11 => 6.0.11 
    vitest: ^3.0.3 => 3.0.3 

[sheremet-va]

This is the same issue as #7308

Please wait for a fix in #7313