JavaScript 简易 Mock 类实现与单元测试示例

(function () {
var KMock = window.KMock = function () {
} 
KMock.prototype.setup = function (methodName) {
var instance = this;
instance[methodName] = {
returnAs: function (fn) {
instance["_" + methodName] = function () {
instance[methodName].invokeNum++;
fn.call();
} 
}, 
isVerify: function (exceptNum) {
if (exceptNum != null) {
return exceptNum == instance[methodName].invokeNum;
} 
else {
return instance[methodName].invokeNum > 0;
} 
}, 
invoke: function () {
instance["_" + methodName].call();
}, 
invokeNum: 0
}; 
return instance[methodName];
} 
})(); 
基于 QUnit 的单元测试应用示例// 自定义Mock类，用于模拟函数并验证调用次数，具体用法如下
<BR><DIV class=cnblogs_Highlighter><PRE class=brush:javascript>/// <reference path="Flight.js" />
/// <reference path="http://demo.jb51.net/jslib/qunit/qunit.js" />
/// <reference path="KMock.js" />
module("enter coin");
test("enter coin while game has not yet start", function () {
var flight = new KFlight();
var mock = new KMock();
mock.setup("draw").returnAs(function () {
}); 
flight.draw = mock.draw.invoke;
equal(flight.coinNum, 0);
equal(flight.gameState, 0);
flight.coinEnter();
equal(flight.coinNum, 0);
equal(flight.gameState, 1);
equal(mock.draw.isVerify(1), true);
});