Using a Bitcoin-Qt v0.16.0 ([downloaded from bitcoin page](https://bitcoin.org/bin/bitcoin-core-0.16.0/bitcoin-0.16.0-osx.dmg)) in an macOS High Sierra 10.13.4 

When I start after a fresh install Bitcoin-Qt as a mainnet node and wallet, the wallet prompt that about 203gb is going to be used in my disk
![image](https://user-images.githubusercontent.com/20187136/39899688-ba820bfe-5493-11e8-87d9-460ed5716a02.png)

When I start the node and wallet as testnet, shows the same message about the 203gb disk usage
![image](https://user-images.githubusercontent.com/20187136/39899756-17b31214-5494-11e8-8a57-60e604e74afb.png)

It seems that the second time the message is wrong, due that the testnet database uses about 14gb.
* will cause the wrong path to be cached.
     */
    static bool pickDataDirectory(interfaces::Node& node);
    /**
     * Determine default data directory for operating system.
     */
    static QString getDefaultDataDirectory();
Q_SIGNALS:
    void requestCheck();
    void stopThread();
public Q_SLOTS:
    void setStatus(int status, const QString &message, quint64 bytesAvailable);
private Q_SLOTS:
    void on_dataDirectory_textChanged(const QString &arg1);
    void on_ellipsisButton_clicked();
    void on_dataDirDefault_clicked();
    void on_dataDirCustom_clicked();
private:
    Ui::Intro *ui;
    QThread *thread;
    QMutex mutex;
    bool signalled;
    QString pathToCheck;
    void startThread();
    void checkPath(const QString &dataDir);
    QString getPathToCheck();
    friend class FreespaceChecker;
};
#endif