Merge pull request #879 from edew/767-chart-update-lag

src/model/time-scale.ts

@@ -1,6 +1,7 @@
 import { DateFormatter } from '../formatters/date-formatter';
 import { DateTimeFormatter } from '../formatters/date-time-formatter';
 
+import { lowerbound } from '../helpers/algorithms';
 import { ensureNotNull } from '../helpers/assertions';
 import { Delegate } from '../helpers/delegate';
 import { ISubscription } from '../helpers/isubscription';
@@ -249,17 +250,13 @@ export class TimeScale {
 			return findNearest ? this._points.length - 1 as TimePointIndex : null;
 		}
 
-		for (let i = 0; i < this._points.length; ++i) {
-			if (time.timestamp === this._points[i].time.timestamp) {
-				return i as TimePointIndex;
-			}
+		const index = lowerbound(this._points, time.timestamp, (a: TimeScalePoint, b: UTCTimestamp) => a.time.timestamp < b);
 
-			if (time.timestamp < this._points[i].time.timestamp) {
-				return findNearest ? i as TimePointIndex : null;
-			}
+		if (time.timestamp < this._points[index].time.timestamp) {
+			return findNearest ? index as TimePointIndex : null;
 		}
 
-		return null;
+		return index as TimePointIndex;
 	}
 
 	public isEmpty(): boolean {

tests/unittests/time-scale.spec.ts

@@ -65,4 +65,63 @@ describe('TimeScale', () => {
 			expect(indexes[0].x).to.be.equal(expectedValue, 'indexesToCoordinates');
 		}
 	});
+
+	describe('timeToIndex', () => {
+		it('should return index for time on scale', () => {
+			const ts = new TimeScale(chartModelMock(), timeScaleOptionsDefaults, fakeLocalizationOptions);
+
+			ts.update(...tsUpdate(2));
+
+			expect(ts.timeToIndex({ timestamp: 0 as UTCTimestamp }, false)).to.be.equal(0);
+			expect(ts.timeToIndex({ timestamp: 1 as UTCTimestamp }, false)).to.be.equal(1);
+			expect(ts.timeToIndex({ timestamp: 2 as UTCTimestamp }, false)).to.be.equal(2);
+		});
+
+		it('should return null for time not on scale', () => {
+			const ts = new TimeScale(chartModelMock(), timeScaleOptionsDefaults, fakeLocalizationOptions);
+
+			ts.update(...tsUpdate(2));
+
+			expect(ts.timeToIndex({ timestamp: -1 as UTCTimestamp }, false)).to.be.equal(null);
+			expect(ts.timeToIndex({ timestamp: 3 as UTCTimestamp }, false)).to.be.equal(null);
+		});
+
+		it('should return null if time scale is empty', () => {
+			const ts = new TimeScale(chartModelMock(), timeScaleOptionsDefaults, fakeLocalizationOptions);
+
+			expect(ts.timeToIndex({ timestamp: 123 as UTCTimestamp }, false)).to.be.equal(null);
+		});
+
+		it('should return null if timestamp is between two values on the scale', () => {
+			const ts = new TimeScale(chartModelMock(), timeScaleOptionsDefaults, fakeLocalizationOptions);
+
+			ts.update(...tsUpdate(1));
+
+			expect(ts.timeToIndex({ timestamp: 0.5 as UTCTimestamp }, false)).to.be.equal(null);
+		});
+
+		it('should return last index if timestamp is greater than last timestamp and findNearest is parameter is true', () => {
+			const ts = new TimeScale(chartModelMock(), timeScaleOptionsDefaults, fakeLocalizationOptions);
+
+			ts.update(...tsUpdate(2));
+
+			expect(ts.timeToIndex({ timestamp: 3 as UTCTimestamp }, true)).to.be.equal(2);
+		});
+
+		it('should return first index if timestamp is less than first timestamp and findNearest is parameter is true', () => {
+			const ts = new TimeScale(chartModelMock(), timeScaleOptionsDefaults, fakeLocalizationOptions);
+
+			ts.update(...tsUpdate(2));
+
+			expect(ts.timeToIndex({ timestamp: -1 as UTCTimestamp }, true)).to.be.equal(0);
+		});
+
+		it('should return next index if timestamp is between two values on the scale and findNearest parameter is true', () => {
+			const ts = new TimeScale(chartModelMock(), timeScaleOptionsDefaults, fakeLocalizationOptions);
+
+			ts.update(...tsUpdate(1));
+
+			expect(ts.timeToIndex({ timestamp: 0.5 as UTCTimestamp }, true)).to.be.equal(1);
+		});
+	});
 });