TanStack

CleanupFn

ts
type CleanupFn = () => void | () => Promise<void>;

Defined in: packages/db/src/types.ts:415

Ends one sync run and releases its adapter-owned resources.

Collection cleanup waits for a returned promise before publishing the cleaned-up status or admitting a replacement sync run. TypeScript permits Promise-returning functions where () => void is expected, so the Promise branch must be explicit here to preserve and await it. Keeping the callable types separate also preserves contextual-void callbacks that return an incidental value.