Clock

The clock of an app: the time, and a timer. The clock that ships is the clock of the system, and a test puts one of its own in its place.

Interface

interface Clock {
  now(): number
  setTimer(at: number, fn: () => void): Cancel
}
type Cancel = () => void

now answers the moment in milliseconds since 1970, in UTC. setTimer has fn called once the clock stands at at, and answers a function that takes the timer back. The engine takes the moment of every call from it: what a query and a change are handed as now, the time of a row, and the time of a line of the log. A clock may have close, which the engine calls when the app is closed.

Example

import { createEngine, type Clock } from 'tentjs/engine'

let moment = Date.UTC(2031, 0, 1)
const clock: Clock = { now: () => moment, setTimer: () => () => undefined }
const engine = createEngine({ makers: { clock: () => clock } })

See also

adapter.Store, adapter.Lease