The request from msw cannot be returned normally in browser mode when using vi.mock

[e7h4n]

Describe the bug

When a request is intercepted by msw, the result returned by msw should be accessible in the test. However, if vi.mock is used in the test, the request intercepted by msw will be hung in the browser. This issue only exists in browser mode.

I am not sure if this issue is the same as #6540 and #6766, but it seems to be somewhat related.

update 1:
#6766 exactly the same problem, and there is another issue thread in msw

Reproduction

• StackBlitz
• Minimal reproducation repo

Reproduction is simple, just use vi.mock to ANY module will prevent msw return response.

The following codes will not work:

export const worker = setupWorker(
  http.get("https://example.com/user", () => {
    return HttpResponse.text("ok");
  })
);

it("should work with msw", async () => {
  await worker.start();
  vi.mock("empty-npm-package"); // this line will prevent msw return response

  const resp = await fetch("https://example.com/user");
  expect(resp.ok).toBeTruthy();
});

System Info

System:
    OS: macOS 15.1
    CPU: (10) arm64 Apple M1 Max
    Memory: 18.92 GB / 64.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 22.6.0 - /opt/homebrew/bin/node
    Yarn: 1.22.4 - /opt/homebrew/bin/yarn
    npm: 10.8.2 - /opt/homebrew/bin/npm
    pnpm: 9.14.4 - /opt/homebrew/bin/pnpm
  Browsers:
    Chrome: 131.0.6778.265
    Safari: 18.1
  npmPackages:
    @vitest/browser: ^3.0.2 => 3.0.2 
    vitest: ^3.0.2 => 3.0.2

Used Package Manager

pnpm

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