fix(vxrn): wrap dev native bundle in function scope to stop global var leaks#715
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…r leaks
rolldown dev() emits the native bundle as a script, so module top-level
vars (RN fetch.js's `var Headers, Request, Response`) leak as
non-configurable global properties. RN's polyfillGlobal then fails
('Failed to set polyfill. Headers is not configurable'), which in dev
becomes a blocking LogBox redbox — the app never mounts, every appium
navigation times out, and the iOS dev jobs hit the 45-min limit.
Wrap everything after the prelude in an IIFE so module top-level vars stay
function-scoped (matching the prod build). The prelude stays at script
scope (it installs globals); the runtime is assigned via globalThis and
HMR updates run through a direct eval, so both survive the wrap.
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🚅 Deployed to the one-pr-715 environment in onestack.dev
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Problem
Native iOS Tests (dev, rolldown)times out (45-min job limit → run cancelled). Root-caused from the cancelled run's failure screenshots: the dev app is stuck on a LogBox redboxFailed to set polyfill. Headers is not configurable., soquick-navigate-pixelnever mounts and every appium navigation waits the full 120s before falling back → the suite blows the timeout.Mechanism (verified against the actual dev bundle)
rolldown's
dev()emits the native bundle as a script. RN'sLibraries/Network/fetch.jsdeclaresvar fetch_hot, fetch$1, Headers, Request, Response$1;at top level — and a top-levelvarin a script creates a non-configurable property on the global object. Soglobal.Headers/global.Requestbecome non-configurable. RN'ssetUpXHRthen runspolyfillGlobal('Headers')→polyfillObjectPropertydoesObject.defineProperty(global, 'Headers', { configurable: true, … }), which throwsCannot redefine property→ RN turns that intoconsole.error('Failed to set polyfill. Headers is not configurable.'). In dev that becomes a blocking redbox.prod is immune: its modules are wrapped in closures (no global leak) and it has no LogBox — which is why
prod, rolldownpasses.Proven in isolation:
Fix
Wrap everything after the prelude in an IIFE (
wrapNativeBundleModuleScope, dev path only) so module top-levelvars stay function-scoped, matching the prod build. The prelude stays at script scope (it deliberately installsglobalThis.global/__DEV__/process/…). Intentional globals survive: the runtime is assigned viaglobalThis.__rolldown_runtime__, and HMR updates run through a directevalinside the wrap, so they still see the closure's helpers/module bindings.Verification
;(function() {is inserted right after the prelude, the leakingvar … Headersdecl is now inside the wrap,})();closes before the (preserved) sourceMappingURL, andnode --checkparses it.wrapNativeBundleModuleScope(wrap structure + no-op without marker + syntactic validity). vxrn suite 39/39, typecheck 0, oxlint 0/0.workflow_dispatchrun of this branch (below).