[petebacondarwin]

Backports #15290 to Vite plugin v1, stacked on #16543's published runtime update.

With server.ws: false, Vite installs no HMR upgrade handler and v1 leaves the browser's raw socket pending. Pass Vite's WebSocket setting into the plugin's upgrade handler and close unclaimed HMR sockets. Preserve enabled HMR, Vite DevTools and Sandbox/Worker WebSocket routing. The source/test diff applies to v1, with the optional argument default kept enabled so preview and other callers that omit it retain their existing handoff; the existing stack contains no equivalent fix. Includes the original plugin patch changeset and tests for enabled, disabled and unspecified HMR.

Validation: Node 22.22.1/pnpm 10.33.0; pnpm check (build, types, lint, format; all 58 tasks) and the WebSocket/container-server suites pass. The first test command accidentally ran the whole plugin suite concurrently with a clean build, which removed generated Worker files mid-test; rerunning affected suites after build completion passes. Parent #16543 validates the published dependency graph and asset/WebSocket dev/preview playgrounds.

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• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows:
  • Additional testing not necessary because:
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: this fixes existing server.ws behavior; the plugin changeset describes it.

Note

This is a contribution from an AI agent: Codex, under the authorized v1 backport automation.

[changeset-bot]

🦋 Changeset detected

Latest commit: ee13faa

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@cloudflare/vite-plugin	Patch

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[workers-devprod]

Codeowners approval required for this PR:

• ✅ @cloudflare/wrangler

[petebacondarwin]

@edmundhung (original author) @petebacondarwin (verified human ant-core approver): please check this v1 backport of #15290 and approve it if it looks good. The original plugin source/tests apply directly to v1, closing raw HMR upgrades when server.ws is disabled while preserving other upgrade owners. It is stacked on #16543, which already supplies the published runtime graph. Build/types/checks and the WebSocket/container-server suites pass.

[clanky-the-clanker]

✅ Approved — This pull request correctly closes HMR upgrades that nothing will handle when server.ws is disabled. It includes tests and a changeset, and no issues were found.

_{The decision is advisory: this comment never approves, blocks or requests changes on the pull request.}

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✅ All checks passed

📋 Code Quality: ✅ LGTM

handleWebSocket destroys a socket only when the upgrade is a Vite HMR request, is not a Sandbox request, and viteWebSocketEnabled is false. DevTools upgrades still go to their own handler. dev.ts passes server.ws !== false, which matches how Vite treats the setting. When the argument is omitted, the default true keeps the existing handoff. The tests check the disabled, enabled and unspecified cases, and also check that dispatchFetch is never called.

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📝 Documentation: ✅ LGTM

The changeset describes the user-facing fix, and the inline comment explains why the socket is destroyed.

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_{Reviewed commit: ee13faab}

[pkg-pr-new]

npm i https://pkg.pr.new/@cloudflare/vite-plugin@16578

commit: ee13faa

[workers-devprod]

Codeowners reviews satisfied