[EskiMojo14]

Description

MSW v3 renames the msw/core/http entry point to msw/http, which is used by @vitest/mocker. This PR takes the more conservative approach of allowing both v2 and v3 (using Promise.any on the dynamic imports and adjusting the peer dependency), meaning that this shouldn't be a breaking change.

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[EskiMojo14]

hmm, even with the vite-ignore, vite is trying to eagerly resolve the import and failing 🤔
unless the vite-ignore isn't applying because of the ts-expect-error comment, which would be a pain

i assume a breaking change to only support v3 would be undesirable?

[fschmutz]

Tried this branch (35f0718) downstream: @vitest/mocker built from the PR and packed, vitest 5.0.3 + @vitest/browser-playwright 5.0.3, msw 3.0.2, vite 8.3.2, Node 26.3.0, pnpm 11.

• pnpm peers check: the "unmet peer msw ^2.4.9 (installed 3.0.2)" warning is gone; our 125 browser-mode tests still pass (they use the vite-plugin interceptor, not the MSW one).
• Vite's dev transform of dist/browser.js still fails with "./core/http" is not exported ... from package msw, same as the e2e jobs here. The @vite-ignore comment is stripped from the built dist, and even import(/* @vite-ignore */ 'msw/core/http') is still resolved because the specifier is a string literal. In a quick check, a non-literal specifier (const s = 'msw/core/http'; import(/* @vite-ignore */ s)) passed the transform; I did not verify its runtime behaviour with msw v2.

[EskiMojo14]

test failures are now unrelated, and appear on main as well (introduced by #11417)

related tests and typechecking are passing

[sheremet-va]

Fixed in #11482

[sxflynn]

Which release of vitest will have this change?