fix(point): fix data.onclick working with sensitivity function

Fix to consider point.sensitivity as function value when
determining mouse pointer is within the point

Fix #3912

src/ChartInternal/shape/point.ts

@@ -378,9 +378,12 @@ export default {
 		const mouse = getPointer(state.event, node);
 		const element = d3Select(node);
 		const prefix = this.isCirclePoint(node) ? "c" : "";
-		const sensitivity = config.point_sensitivity === "radius" ?
+		let pointSensitivity = config.point_sensitivity;
+
+		pointSensitivity = pointSensitivity === "radius" ?
 			node.getAttribute("r") :
-			config.point_sensitivity;
+			(isFunction(pointSensitivity) ? node && pointSensitivity(node) : pointSensitivity);
+
 		let cx = +element.attr(`${prefix}x`);
 		let cy = +element.attr(`${prefix}y`);
 
@@ -394,7 +397,7 @@ export default {
 
 		return Math.sqrt(
 			Math.pow(cx - mouse[0], 2) + Math.pow(cy - mouse[1], 2)
-		) < (r || sensitivity);
+		) < (r || pointSensitivity);
 	},
 
 	/**

test/shape/point-spec.ts

@@ -277,7 +277,7 @@ describe("SHAPE POINT", () => {
 				tooltip: {
 					grouped: false
 				}
-			};
+			}; 
 		});
 
 		it("default sensitivity", () => {
@@ -431,8 +431,46 @@ describe("SHAPE POINT", () => {
 
 			expect(args.data.onclick.called).to.be.true;
 		});
-	});
 
+		it("set options", () => {
+			args = {
+				data: {
+					columns: [
+					  ["data1", 450],
+					],
+					onclick: sinon.spy(function() {
+						console.log("3333333")
+					}),
+					type: "line"
+				},
+				point: {
+					sensitivity: function(r) {
+					  return 10;
+					},
+					r: 10,
+					focus: {
+						expand: {
+							r: 10
+						}
+					}
+				},
+			};
+		});
+
+		it("should data.onclick callback called.", () => {
+			const {circles} = chart.$;
+			const {$el: {eventRect}} = chart.internal;
+			const rect = circles.node().getBoundingClientRect();
+
+			fireEvent(eventRect.node(), "click", {
+				clientX: 300,
+				clientY: 40
+			}, chart); 
+
+			expect(args.data.onclick.called).to.be.true;
+		});
+	}); 
+
 	describe("point.focus.only", () => {
 		beforeAll(() => {
 			args = {