NodeJS中的布尔表达式/ Regexp

Question

我在Node.JS中遇到了一个问题，我不确定它是否可能是一些奇怪的语言功能，一个错误或者我是否过度劳累等等。不要判断。不过，我已经向另外两个人展示了这一点。

    var testa = (req.direction == zCore.get('DIRECTION.Incoming')),
        testb = burnerRE.test(req.text),
        testc = yuilopRE.test(req.text),
        testd = viberRE.test(req.text),
        teste = whatsappRE.test(req.text),
        testf = kakaotalkRE.test(req.text),
        testg = generalCodeRE.test(req.text)
    ;

    // THIS IS TRUE
    console.log(testa);

    // ONE OF THESE WILL BE TRUE
    console.log(testb);
    console.log(testc);
    console.log(testd);
    console.log(testd);
    console.log(teste);
    console.log(testf);
    console.log(testg);


    // THIS IS SOME HOW FALSE
    console.log(testa && (testb || testc || testd || teste || testf || testg));