不确定从哪里开始，或者用mocha和chai测试以下代码的最佳方法是什么：
module.exports = function trackCustomDyEvents(events){
let $;
trackEvents();
function trackEvents() {
events.forEach((event) => {
$(document).on(event.type, event.element, () => {
if (!event.predicate()) return;
window.DY.API('event', {
name: event.name
});
});
});
}
};
这里是单元测试解决方案，您需要一个sinon.js之类的存根库，并且我假设您使用jquery。
index.js：
window.DY = window.DY || {};
window.DY.API = function(event, obj) {
// Your real implementation
};
module.exports = function trackCustomDyEvents(events) {
const $ = require("jquery");
trackEvents();
function trackEvents() {
events.forEach((event) => {
$(document).on(event.type, event.element, () => {
if (!event.predicate()) return;
window.DY.API("event", {
name: event.name,
});
});
});
}
};
index.test.js：
const jsdom = require("jsdom");
const sinon = require("sinon");
const proxyquire = require("proxyquire");
describe("trackCustomDyEvents", () => {
before(() => {
const html = '<!doctype html><html><head><meta charset="utf-8">' + "</head><body></body></html>";
const url = "http://localhost";
const document = new jsdom.JSDOM(html, { url });
const window = document.window;
global.document = window.document;
global.window = window;
});
afterEach(() => {
sinon.restore();
});
it("should call DY.API", () => {
const onStub = sinon.stub().yields();
const jqueryStub = sinon.stub().callsFake(() => ({
on: onStub,
}));
const trackCustomDyEvents = proxyquire("./", {
jquery: jqueryStub,
});
const APISpy = sinon.stub(window.DY, "API");
const predicateStub = sinon.stub().returns(true);
const events = [
{ type: "click", element: "button", name: "a", predicate: predicateStub },
{ type: "submit", element: "form", name: "b", predicate: predicateStub },
];
trackCustomDyEvents(events);
sinon.assert.calledWithExactly(onStub.firstCall, "click", "button", sinon.match.func);
sinon.assert.calledWithExactly(onStub.secondCall, "submit", "form", sinon.match.func);
sinon.assert.calledTwice(predicateStub);
sinon.assert.calledWithExactly(APISpy.firstCall, "event", { name: "a" });
sinon.assert.calledWithExactly(APISpy.secondCall, "event", { name: "b" });
});
it("should not call DY.API", () => {
const onStub = sinon.stub().yields();
const jqueryStub = sinon.stub().callsFake(() => ({
on: onStub,
}));
const trackCustomDyEvents = proxyquire("./", {
jquery: jqueryStub,
});
const APISpy = sinon.stub(window.DY, "API");
const predicateStub = sinon.stub().returns(false);
const events = [
{ type: "click", element: "button", name: "a", predicate: predicateStub },
{ type: "submit", element: "form", name: "b", predicate: predicateStub },
];
trackCustomDyEvents(events);
sinon.assert.calledWithExactly(onStub.firstCall, "click", "button", sinon.match.func);
sinon.assert.calledWithExactly(onStub.secondCall, "submit", "form", sinon.match.func);
sinon.assert.calledTwice(predicateStub);
sinon.assert.notCalled(APISpy);
});
});
单元测试结果覆盖率100％：
trackCustomDyEvents
✓ should call DY.API (76ms)
✓ should not call DY.API
2 passing (146ms)
---------------|----------|----------|----------|----------|-------------------|
File | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s |
---------------|----------|----------|----------|----------|-------------------|
All files | 100 | 100 | 91.67 | 100 | |
index.js | 100 | 100 | 80 | 100 | |
index.test.js | 100 | 100 | 100 | 100 | |
---------------|----------|----------|----------|----------|-------------------|
源代码：https://github.com/mrdulin/mocha-chai-sinon-codelab/tree/master/src/stackoverflow/59569112