opencode/packages/core/test/lib/eventually.ts

import { Effect } from "effect"

// Bounded by elapsed real time rather than attempts, so a busy machine still fits. Sleeps on a real timer, so it
// also works under TestClock.
export const eventually = <A, E, R>(
  effect: Effect.Effect<A, E, R>,
  predicate: (value: A) => boolean,
): Effect.Effect<A, E | Error, R> =>
  Effect.gen(function* () {
    const deadline = Date.now() + 10_000
    while (true) {
      const value = yield* effect
      if (predicate(value)) return value
      if (Date.now() > deadline) return yield* Effect.fail(new Error("Timed out waiting for value"))
      yield* Effect.promise(() => Bun.sleep(1))
    }
  })

export const waitUntil = <E, R>(condition: Effect.Effect<boolean, E, R>) =>
  eventually(condition, (ready) => ready).pipe(Effect.asVoid)