vitest/browser fails to run when the dependent package has chai v5 about vitest HOT 4 OPEN

Chai 5 is not supported at the moment.

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I have the same issue after upgrading to v1.3.1 from v1.2.1, regardless the presence of chai 5.

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I think this is yet another case of missing optimizeDeps of Vitest cjs dependencies though I'm not really sure why this manifests on when there are multiple chai versions.
(EDIT: I think this is because when a project has its own chai dependency, there will be two node_modules/chai and node_modules/@vitest/expect/node_modules/chai.)

In your reproduction, adding this should should help for the time being.

import { defineConfig } from "vitest/config";

export default defineConfig({
  optimizeDeps: {
    include: ["vitest > @vitest/expect > chai"]
  },
  test: { ... }
});

As mentioned in #5332 (comment), currently Vitest uses chai v4, so same chai instance won't be shared when using it like below. But I suppose the issue is not expecting such use case, so probably we can fix optimizeDeps.include.

import * as chai from "chai"; // project uses chai v5 
import { expect } from "vitest"; // internally uses a different copy of chai v4

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Hmm, maybe this might be tricky since loupe is in optimizeDeps.exclude #5082 and this is happening when I add vitest > @vitest/expect > chai in optimizeDeps.include and run test/browser:

[vite] Internal server error: Failed to resolve import "loupe" from "node_modules/.vite/deps/chunk-R6V3PAXC.js?v=d4c039b0". Does the file exist?
  Plugin: vite:import-analysis
  File: /home/hiroshi/code/others/vitest/test/browser/node_modules/.vite/deps/chunk-R6V3PAXC.js?v=d4c039b0:3:48
  1  |  const __vi_inject__ = { [Symbol.toStringTag]: "Module" };
  2  |  import { __vi_inject__ as __vi_esm_0__ } from './chunk-5YJXGM4D.js'
  3  |  import { __vi_inject__ as __vi_esm_1__ } from 'loupe'

Maybe original reproduction works only because of flat node modules, so loupe is always visible from node_modules/.vite/deps. If it were on pnpm, probably it'll still break.

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