add interval to clock

This commit is contained in:
Bruno Windels 2020-05-05 23:12:14 +02:00
parent f90b435362
commit 4ffaa82435
2 changed files with 64 additions and 0 deletions

View File

@ -18,6 +18,34 @@ class Timeout {
}
}
class Interval {
constructor(elapsed, ms, callback) {
this._start = elapsed.get();
this._last = this._start;
this._interval = ms;
this._callback = callback;
this._subscription = elapsed.subscribe(this._update.bind(this));
}
_update(elapsed) {
const prevAmount = Math.floor((this._last - this._start) / this._interval);
const newAmount = Math.floor((elapsed - this._start) / this._interval);
const amountDiff = Math.max(0, newAmount - prevAmount);
this._last = elapsed;
for (let i = 0; i < amountDiff; ++i) {
this._callback();
}
}
dispose() {
if (this._subscription) {
this._subscription();
this._subscription = null;
}
}
}
class TimeMeasure {
constructor(elapsed) {
this._elapsed = elapsed;
@ -47,6 +75,10 @@ export class Clock {
return new Timeout(this._elapsed, ms);
}
createInterval(callback, ms) {
return new Interval(this._elapsed, ms, callback);
}
now() {
return this._baseTimestamp + this.elapsed;
}
@ -72,6 +104,16 @@ export function tests() {
const promise = timeout.elapsed();
assert(promise instanceof Promise);
await promise;
},
"test interval": assert => {
const clock = new Clock();
let counter = 0;
const interval = clock.createInterval(() => counter += 1, 200);
clock.elapse(150);
assert.strictEqual(counter, 0);
clock.elapse(500);
assert.strictEqual(counter, 3);
interval.dispose();
}
}
}

View File

@ -25,8 +25,26 @@ class Timeout {
this._reject = null;
}
}
dispose() {
this.abort();
}
}
class Interval {
constructor(ms, callback) {
this._handle = setInterval(callback, ms);
}
dispose() {
if (this._handle) {
clearInterval(this._handle);
this._handle = null;
}
}
}
class TimeMeasure {
constructor() {
this._start = window.performance.now();
@ -46,6 +64,10 @@ export class Clock {
return new Timeout(ms);
}
createInterval(callback, ms) {
return new Interval(ms, callback);
}
now() {
return Date.now();
}