Function propagateAbort

src/utils/abortController.ts:30–36

* Propagates abort from a parent to a weakly-referenced child controller. * Both parent and child are weakly held — neither direction creates a * strong reference that could prevent GC. * Module-scope function avoids per-call closure allocation.

(
  this: WeakRef<AbortController>,
  weakChild: WeakRef<AbortController>,
)

 * Module-scope function avoids per-call closure allocation.
 */
function propagateAbort(
  this: WeakRef<AbortController>,
  weakChild: WeakRef<AbortController>,
): void {
  const parent = this.deref()
  weakChild.deref()?.abort(parent?.signal.reason)
}

/**
 * Removes an abort handler from a weakly-referenced parent signal.