fix: preserve native dispatchEvent for Deno compatibility#7
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Replace GlobalRegistrator.register() with new GlobalWindow() from happy-dom, then selectively install DOM globals while preserving any existing dispatchEvent, Event, and CustomEvent on globalThis. The old approach called GlobalRegistrator.register() which unconditionally overwrites globalThis.dispatchEvent with Happy DOM's implementation. Deno's runtime dispatches a native 'beforeunload' event on process exit using its own Event constructor; Happy DOM's dispatchEvent rejects it with a TypeError because the event is not an instance of Happy DOM's internal Event class. The fix saves the runtime's native event primitives before setting up the Happy DOM window and restores them afterward. This leaves Happy DOM's DOM APIs (document, HTMLElement, etc.) fully functional while keeping Deno's shutdown path intact. Also removes @happy-dom/global-registrator from peerDependencies since it is no longer used.
This was referenced Apr 5, 2026
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Problem
When running tests with Happy DOM under Deno, the process exits with:
Deno's runtime dispatches a native
beforeunloadevent on process exit. The currentdom-env.tsusesGlobalRegistrator.register()which unconditionally overwritesglobalThis.dispatchEventwith Happy DOM's version. Happy DOM's implementation validates that the event argument is an instance of its own internalEventclass — it rejects Deno's nativeEventwith aTypeError.Fix
Replace
GlobalRegistrator.register()withnew GlobalWindow()fromhappy-dom, then install each DOM global individually. Before install, save any existingdispatchEvent,Event, andCustomEventfromglobalThisand restore them after, so Deno's shutdown path remains intact.Changes
src/dom-env.ts: replaceGlobalRegistrator.register()withnew GlobalWindow()+ selective global install, preserving nativedispatchEvent/Event/CustomEventpackage.json: remove@happy-dom/global-registratorfrompeerDependenciesandpeerDependenciesMeta— it is no longer used;happy-dom(already an optional peer) is sufficientTesting
All three runtimes pass: Node 3/3, Bun 3/3, Deno 3/3.