Function.test(thisObject, argsArray, forecast) の実装

gistfile1.js

// 関数の返す結果が想定した結果と同等かをチェックする test メソッド
// Func.test(thisObj, argsArray, forecast);
if (! Function.prototype.test) {
    Function.prototype.test = function (that, args, forecast) {
        var result = this.apply(that, args);

        result   = JSON.stringify(result);
        forecast = JSON.stringify(forecast);

        // return (result === forecast) ? true : false; 本当はこっち

        console.log(
            (result === forecast)
                ? [ 'success:', result ].join('\t')
                : [ '!failed:', result, forecast ].join('\t')
        );
    };
};

function add (a, b) {
    return (a + b);
}

var yuki = {
    loves : 'Nao'
};

var tomo = {
    love : function () {
        return this.loves;
    },
    loves : 'Yuki',
};

// * TEST * //

add.test(null, [2, 3], 5);

var whoLovesWho = tomo.love;

whoLovesWho.test(tomo, [], 'Yuki');
whoLovesWho.test(yuki, [], 'Nao');