Resolve the qt/guiutil <-> qt/optionsmodal CD

This pull request attempts to resolve the `qt/guiutil` <-> `qt/optionsmodel`
circular dependency.

The circular dependency is resolved by moving the `Intro::getDefaultDataDirectory`
member function to `GUIUtil::getDefaultDataDirectory`.

src/qt/guiutil.cpp

@@ -244,6 +244,11 @@ QList<QModelIndex> getEntryData(QAbstractItemView *view, int column)
     return view->selectionModel()->selectedRows(column);
 }
 
+QString getDefaultDataDirectory()
+{
+    return boostPathToQString(GetDefaultDataDir());
+}
+
 QString getSaveFileName(QWidget *parent, const QString &caption, const QString &dir,
     const QString &filter,
     QString *selectedSuffixOut)

src/qt/guiutil.h

@@ -79,6 +79,11 @@ namespace GUIUtil
 
     void setClipboard(const QString& str);
 
+    /**
+     * Determine default data directory for operating system.
+     */
+    QString getDefaultDataDirectory();
+
     /** Get save filename, mimics QFileDialog::getSaveFileName, except that it appends a default suffix
         when no suffix is provided by the user.
 

src/qt/intro.cpp

@@ -168,7 +168,7 @@ QString Intro::getDataDirectory()
 void Intro::setDataDirectory(const QString &dataDir)
 {
     ui->dataDirectory->setText(dataDir);
-    if(dataDir == getDefaultDataDirectory())
+    if(dataDir == GUIUtil::getDefaultDataDirectory())
     {
         ui->dataDirDefault->setChecked(true);
         ui->dataDirectory->setEnabled(false);
@@ -180,11 +180,6 @@ void Intro::setDataDirectory(const QString &dataDir)
     }
 }
 
-QString Intro::getDefaultDataDirectory()
-{
-    return GUIUtil::boostPathToQString(GetDefaultDataDir());
-}
-
 bool Intro::pickDataDirectory(interfaces::Node& node)
 {
     QSettings settings;
@@ -193,7 +188,7 @@ bool Intro::pickDataDirectory(interfaces::Node& node)
     if(!gArgs.GetArg("-datadir", "").empty())
         return true;
     /* 1) Default data directory for operating system */
-    QString dataDir = getDefaultDataDirectory();
+    QString dataDir = GUIUtil::getDefaultDataDirectory();
     /* 2) Allow QSettings to override default dir */
     dataDir = settings.value("strDataDir", dataDir).toString();
 
@@ -239,7 +234,7 @@ bool Intro::pickDataDirectory(interfaces::Node& node)
      * override -datadir in the bitcoin.conf file in the default data directory
      * (to be consistent with bitcoind behavior)
      */
-    if(dataDir != getDefaultDataDirectory()) {
+    if(dataDir != GUIUtil::getDefaultDataDirectory()) {
         node.softSetArg("-datadir", GUIUtil::qstringToBoostPath(dataDir).string()); // use OS locale for path setting
     }
     return true;
@@ -293,7 +288,7 @@ void Intro::on_ellipsisButton_clicked()
 
 void Intro::on_dataDirDefault_clicked()
 {
-    setDataDirectory(getDefaultDataDirectory());
+    setDataDirectory(GUIUtil::getDefaultDataDirectory());
 }
 
 void Intro::on_dataDirCustom_clicked()

src/qt/intro.h

@@ -48,11 +48,6 @@ public:
      */
     static bool pickDataDirectory(interfaces::Node& node);
 
-    /**
-     * Determine default data directory for operating system.
-     */
-    static QString getDefaultDataDirectory();
-
 Q_SIGNALS:
     void requestCheck();
 

src/qt/optionsmodel.cpp

@@ -17,7 +17,6 @@
 #include <net.h>
 #include <netbase.h>
 #include <txdb.h> // for -dbcache defaults
-#include <qt/intro.h>
 
 #include <QNetworkProxy>
 #include <QSettings>
@@ -110,7 +109,7 @@ void OptionsModel::Init(bool resetSettings)
         addOverriddenOption("-par");
 
     if (!settings.contains("strDataDir"))
-        settings.setValue("strDataDir", Intro::getDefaultDataDirectory());
+        settings.setValue("strDataDir", GUIUtil::getDefaultDataDirectory());
 
     // Wallet
 #ifdef ENABLE_WALLET
@@ -187,7 +186,7 @@ void OptionsModel::Reset()
     BackupSettings(GetDataDir(true) / "guisettings.ini.bak", settings);
 
     // Save the strDataDir setting
-    QString dataDir = Intro::getDefaultDataDirectory();
+    QString dataDir = GUIUtil::getDefaultDataDirectory();
     dataDir = settings.value("strDataDir", dataDir).toString();
 
     // Remove all entries from our QSettings object

test/lint/lint-circular-dependencies.sh

@@ -36,7 +36,6 @@ EXPECTED_CIRCULAR_DEPENDENCIES=(
     "txmempool -> validation -> validationinterface -> txmempool"
     "qt/addressbookpage -> qt/bitcoingui -> qt/walletview -> qt/receivecoinsdialog -> qt/addressbookpage"
     "qt/addressbookpage -> qt/bitcoingui -> qt/walletview -> qt/signverifymessagedialog -> qt/addressbookpage"
-    "qt/guiutil -> qt/walletmodel -> qt/optionsmodel -> qt/intro -> qt/guiutil"
     "qt/addressbookpage -> qt/bitcoingui -> qt/walletview -> qt/sendcoinsdialog -> qt/sendcoinsentry -> qt/addressbookpage"
 )