add FunnelChart spec

src/FunnelChart.js

@@ -124,6 +124,7 @@ export default class FunnelChart extends React.Component {
               d={pathStr}
               className={`${getValue(pathClassName, d, i) || ""}`}
               style={style}
+              key={i}
             />
           );
         })}

tests/jsdom/spec/FunnelChart.spec.js

@@ -0,0 +1,62 @@
+import React from "react";
+import * as d3 from "d3";
+import _ from "lodash";
+import sinon from "sinon";
+import { expect } from "chai";
+import { mount } from "enzyme";
+
+import { FunnelChart } from "../../../src/index.js";
+import { getValue } from "../../../src/utils/Data.js";
+
+describe("FunnelChart", () => {
+  const funnelData = [
+    { observation: 1, value: 100 },
+    { observation: 2, value: 85 },
+    { observation: 3, value: 42 },
+    { observation: 4, value: 37 },
+    { observation: 5, value: 12 }
+  ];
+
+  const props = {
+    data: funnelData,
+    x: d => d.value,
+    y: d => d.observation,
+    pathClassName: "path-class",
+    horizontal: true,
+    xScale: d3
+      .scaleLinear()
+      .domain([-1, 0, 1])
+      .range([0, 30]),
+    yScale: d3
+      .scaleLinear()
+      .domain([0, 10])
+      .range([0, 30]),
+    pathStyle: { fill: "yellow" }
+  };
+
+  it("renders a funnel chart", () => {
+    const chart = mount(<FunnelChart {...props} />);
+    const group = chart.find("g.rct-funnel-chart");
+    expect(group).to.have.length(1);
+    expect(group.find("path")).to.have.length(props.data.length - 1);
+
+    group.find('path').forEach((path) => {
+      const pathD = path.getNode().getAttribute('d');
+
+      expect(pathD).not.to.include('NaN');
+      }
+    );
+
+    const lastPath = group.find('path').last();
+    const pathData = lastPath.getNode().getAttribute('d');
+    expect(pathData).to.equal('M1140,12L390,15L-330,15L-1080,12Z');
+  });
+
+  it("passes props correctly", () => {
+    const chart = mount(<FunnelChart {...props} />);
+    const lastPath = chart.find("path").last();
+    expect(lastPath.props().className).to.include(props.pathClassName);
+    expect(lastPath.props().style).to.contain(props.pathStyle);
+    expect(lastPath.props().d).to.be.a("string");
+  });
+});