Consider all timestamps for bar measuring (chartjs#7421)

* Consider all timestamps for bar measuring
* Fix watched tests for updated file names
* Add test of sparse bar time scales

Author: etimberg

karma.conf.js

@@ -14,7 +14,7 @@ module.exports = function(karma) {
 	// we will prefer the unminified build which is easier to browse and works
 	// better with source mapping. In other cases, pick the minified build to
 	// make sure that the minification process (terser) doesn't break anything.
-	const regex = args.watch ? /Chart\.js$/ : /Chart\.min\.js$/;
+	const regex = args.watch ? /chart\.js$/ : /chart\.min\.js$/;
 	const build = builds.filter(v => v.output.file.match(regex))[0];
 
 	if (args.watch) {

src/scales/scale.time.js

@@ -686,7 +686,7 @@ class TimeScale extends Scale {
 		me._majorUnit = !tickOpts.major.enabled || me._unit === 'year' ? undefined
 			: determineMajorUnit(me._unit);
 		me._table = buildLookupTable(getTimestampsForTable(me), min, max, distribution);
-		me._offsets = computeOffsets(me._table, getDataTimestamps(me), min, max, options);
+		me._offsets = computeOffsets(me._table, timestamps, min, max, options);
 
 		if (options.reverse) {
 			ticks.reverse();

test/fixtures/scale.time/bar-large-gap-between-data.js

@@ -0,0 +1,57 @@
+var date = moment('May 24 2020', 'MMM DD YYYY');
+
+module.exports = {
+	threshold: 0.05,
+	config: {
+		type: 'bar',
+		data: {
+			datasets: [{
+				backgroundColor: 'rgba(255, 0, 0, 0.5)',
+				data: [
+					{
+						x: date.clone().add(-2, 'day'),
+						y: 20,
+					},
+					{
+						x: date.clone().add(-1, 'day'),
+						y: 30,
+					},
+					{
+						x: date,
+						y: 40,
+					},
+					{
+						x: date.clone().add(1, 'day'),
+						y: 50,
+					},
+					{
+						x: date.clone().add(7, 'day'),
+						y: 10,
+					}
+				]
+			}]
+		},
+		options: {
+			legend: false,
+			scales: {
+				x: {
+					display: false,
+					type: 'time',
+					distribution: 'linear',
+					ticks: {
+						source: 'auto'
+					},
+					time: {
+						unit: 'day'
+					}
+				},
+				y: {
+					display: false
+				}
+			}
+		}
+	},
+	options: {
+		spriteText: true
+	}
+};