Browser Mode doesn't work

[LostKobrakai]

Describe the bug

When running
npx vitest run

Error: Cannot define a nested project for a chrome browser. The project name "chrome" was already defined. If you have multiple instances for the same browser, make sure to define a custom "name". All projects in a workspace should have unique names. Make sure your configuration is correct.

config:

 test: {
      // globals: true,
      // setupFiles: ["node_modules/@testing-library/jest-dom/vitest"],
      // if you have few tests, try commenting this
      // out to improve performance:
      isolate: false,
      coverage: {
        provider: "istanbul", // or 'v8'
        enabled: true,
        reporter: ["html"],
        include: ["js/*", "js/**"],
        exclude: ["js/storybook.js"],
      },
      browser: {
        enabled: true,
        provider: "webdriverio",
        headless: true,
        instances: [{ browser: "chrome" }],
      },
    }

I'm not using workspaces. Also the project name is whatever I put as name of the browser instance - the function simply seems to be called multiple times, by definitions putting the same key in the set names set twice.

Reproduction

https://stackblitz.com/edit/vitest-dev-vitest-91sxljov?file=vite.config.ts seems to be related to the solid plugin, without the plugin things work.

System Info

System:
    OS: macOS 15.1.1
    CPU: (14) arm64 Apple M4 Pro
    Memory: 1.70 GB / 48.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 20.13.1 - ~/.local/share/mise/installs/node/20.13.1/bin/node
    npm: 10.5.2 - ~/.local/share/mise/installs/node/20.13.1/bin/npm
  Browsers:
    Chrome: 131.0.6778.265
    Safari: 18.1.1
  npmPackages:
    @vitest/browser: 3.0.x => 3.0.4
    @vitest/coverage-istanbul: 3.0.x => 3.0.4
    vite: 6.0.x => 6.0.11
    vitest: 3.0.x => 3.0.4

Used Package Manager

npm

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.
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• The provided reproduction is a minimal reproducible example of the bug.

[github-actions]

Hello @LostKobrakai. Please provide a minimal reproduction using a GitHub repository or StackBlitz (you can also use examples). Issues marked with needs reproduction will be closed if they have no activity within 3 days.

[kettanaito]

The error seems to suggest that your vite.config.ts is run twice. You can confirm this by giving your browser config a name. It will be included in the error message despite you defining it once (naturally, Solid plugin doesn't know your unique name).

You can confirm this by logging out the resolved config:

export default defineConfig({
  plugins: [
    solidPlugin(),
+    {
+      name: 'debug',
+      enforce: 'post',
+      configResolved(config) {
+        console.log(config.test?.browser);
+      },
+    },
  ],

And seeing this in test.browser:

{
  enabled: true,
  provider: 'webdriverio',
  headless: true,
  instances: [
    { browser: 'chrome', name: 'chrome' },
    { browser: 'chrome', name: 'chrome' }
  ]
}

Upon further investigation, you can find a bug already reported to vite-plugin-solid: solidjs/vite-plugin-solid#170 (comment).

This isn't an issue with Vitest. The Solid plugin returns a full { test } object again, which causes your configuration to repeat, resulting in the error.

[hi-ogawa]

@kettanaito Thanks for looking into this 👍 Closing this one in favor of solid's issue (also the duplicate of #7284)