From: Jukka Kurkela <jukka.kurkela@gmail.com>
Date: Fri, 10 Jan 2020 23:31:17 +0000 (+0200)
Subject: Re-parse existing elements when data is replaced (#6925)
X-Git-Tag: v3.0.0-alpha~135
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5054ecfd7eff02a59350c446cda31bf01250373e;p=thirdparty%2FChart.js.git

Re-parse existing elements when data is replaced (#6925)

* Re-parse existing elements when data is replaced
* Update test
---

diff --git a/src/core/core.datasetController.js b/src/core/core.datasetController.js
index abe8e4614..c240d7844 100644
--- a/src/core/core.datasetController.js
+++ b/src/core/core.datasetController.js
@@ -1051,6 +1051,10 @@ helpers.extend(DatasetController.prototype, {
 
 		if (numData > numMeta) {
 			me.insertElements(numMeta, numData - numMeta);
+			if (changed && numMeta) {
+				// insertElements parses the new elements. The old ones might need parsing too.
+				me._parse(0, numMeta);
+			}
 		} else if (numData < numMeta) {
 			meta.data.splice(numData, numMeta - numData);
 			meta._parsed.splice(numData, numMeta - numData);
diff --git a/test/specs/core.datasetController.tests.js b/test/specs/core.datasetController.tests.js
index 37545d79b..8d04dbee3 100644
--- a/test/specs/core.datasetController.tests.js
+++ b/test/specs/core.datasetController.tests.js
@@ -299,14 +299,22 @@ describe('Chart.DatasetController', function() {
 		var meta = chart.getDatasetMeta(0);
 
 		expect(meta.data.length).toBe(6);
+		expect(meta._parsed.map(p => p.y)).toEqual(data0);
 
 		chart.data.datasets[0].data = data1;
 		chart.update();
 
 		expect(meta.data.length).toBe(3);
+		expect(meta._parsed.map(p => p.y)).toEqual(data1);
+
+		data1.push(9);
+		expect(meta.data.length).toBe(4);
+
+		chart.data.datasets[0].data = data0;
+		chart.update();
 
-		data1.push(9, 10, 11);
 		expect(meta.data.length).toBe(6);
+		expect(meta._parsed.map(p => p.y)).toEqual(data0);
 	});
 
 	it('should re-synchronize metadata when data are unusually altered', function() {