From: Evert Timberg <evert.timberg+github@gmail.com>
Date: Sat, 30 Jul 2016 18:46:28 +0000 (-0400)
Subject: Handle the case where all points are skipped in a line
X-Git-Tag: v2.2.2~19^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F3067%2Fhead;p=thirdparty%2FChart.js.git

Handle the case where all points are skipped in a line
---

diff --git a/src/elements/element.line.js b/src/elements/element.line.js
index 76a59d58e..4d5a10837 100644
--- a/src/elements/element.line.js
+++ b/src/elements/element.line.js
@@ -116,7 +116,7 @@ module.exports = function(Chart) {
 					}
 				}
 
-				if (!loop) {
+				if (!loop && lastDrawnIndex !== -1) {
 					ctx.lineTo(points[lastDrawnIndex]._view.x, scaleZero);
 				}
 
diff --git a/test/element.line.tests.js b/test/element.line.tests.js
index 085f1b115..38a56fe3e 100644
--- a/test/element.line.tests.js
+++ b/test/element.line.tests.js
@@ -816,6 +816,130 @@ describe('Line element tests', function() {
 		expect(mockContext.getCalls()).toEqual(expected);
 	});
 
+	it('should skip points correctly when all points are skipped', function() {
+		var mockContext = window.createMockContext();
+
+		// Create our points
+		var points = [];
+		points.push(new Chart.elements.Point({
+			_datasetindex: 2,
+			_index: 0,
+			_view: {
+				x: 0,
+				y: 10,
+				controlPointNextX: 0,
+				controlPointNextY: 10,
+				skip: true
+			}
+		}));
+		points.push(new Chart.elements.Point({
+			_datasetindex: 2,
+			_index: 1,
+			_view: {
+				x: 5,
+				y: 0,
+				controlPointPreviousX: 5,
+				controlPointPreviousY: 0,
+				controlPointNextX: 5,
+				controlPointNextY: 0,
+				skip: true
+			}
+		}));
+		points.push(new Chart.elements.Point({
+			_datasetindex: 2,
+			_index: 2,
+			_view: {
+				x: 15,
+				y: -10,
+				controlPointPreviousX: 15,
+				controlPointPreviousY: -10,
+				controlPointNextX: 15,
+				controlPointNextY: -10,
+				skip: true
+			}
+		}));
+		points.push(new Chart.elements.Point({
+			_datasetindex: 2,
+			_index: 3,
+			_view: {
+				x: 19,
+				y: -5,
+				controlPointPreviousX: 19,
+				controlPointPreviousY: -5,
+				controlPointNextX: 19,
+				controlPointNextY: -5,
+				skip: true
+			}
+		}));
+
+		var line = new Chart.elements.Line({
+			_datasetindex: 2,
+			_chart: {
+				ctx: mockContext,
+			},
+			_children: points,
+			// Need to provide some settings
+			_view: {
+				fill: true,
+				scaleZero: 2, // for filling lines
+				tension: 0.0, // no bezier curve for now
+				spanGaps: true
+			}
+		});
+
+		line.draw();
+
+		var expected = [{
+			name: 'save',
+			args: []
+		}, {
+			name: 'beginPath',
+			args: []
+		}, {
+			name: 'moveTo',
+			args: [0, 2]
+		}, {
+			name: 'setFillStyle',
+			args: ['rgba(0,0,0,0.1)']
+		}, {
+			name: 'closePath',
+			args: []
+		}, {
+			name: 'fill',
+			args: []
+		}, {
+			name: 'setLineCap',
+			args: ['butt']
+		}, {
+			name: 'setLineDash',
+			args: [
+				[]
+			]
+		}, {
+			name: 'setLineDashOffset',
+			args: [0]
+		}, {
+			name: 'setLineJoin',
+			args: ['miter']
+		}, {
+			name: 'setLineWidth',
+			args: [3]
+		}, {
+			name: 'setStrokeStyle',
+			args: ['rgba(0,0,0,0.1)']
+		}, {
+			name: 'beginPath',
+			args: []
+		}, {
+			name: 'stroke',
+			args: []
+		}, {
+			name: 'restore',
+			args: []
+		}];
+		expect(mockContext.getCalls()).toEqual(expected);
+	});
+
 	it('should skip the first point correctly', function() {
 		var mockContext = window.createMockContext();