Use QString literals

This patch covers src/gui and some leftovers from previous commit.

src/base/utils/foreignapps.cpp

@@ -42,6 +42,7 @@
 #include <QDir>
 #endif
 
+#include "base/global.h"
 #include "base/logger.h"
 #include "base/utils/bytearray.h"
 
@@ -52,7 +53,7 @@ namespace
     bool testPythonInstallation(const QString &exeName, PythonInfo &info)
     {
         QProcess proc;
-        proc.start(exeName, {"--version"}, QIODevice::ReadOnly);
+        proc.start(exeName, {u"--version"_qs}, QIODevice::ReadOnly);
         if (proc.waitForFinished() && (proc.exitCode() == QProcess::NormalExit))
         {
             QByteArray procOutput = proc.readAllStandardOutput();
@@ -69,8 +70,8 @@ namespace
 
             // User reports: `python --version` -> "Python 3.6.6+"
             // So trim off unrelated characters
-            const QString versionStr = outputSplit[1];
-            const int idx = versionStr.indexOf(QRegularExpression("[^\\.\\d]"));
+            const auto versionStr = QString::fromLocal8Bit(outputSplit[1]);
+            const int idx = versionStr.indexOf(QRegularExpression(u"[^\\.\\d]"_qs));
 
             try
             {
@@ -274,10 +275,10 @@ PythonInfo Utils::ForeignApps::pythonInfo()
     static PythonInfo pyInfo;
     if (!pyInfo.isValid())
     {
-        if (testPythonInstallation("python3", pyInfo))
+        if (testPythonInstallation(u"python3"_qs, pyInfo))
             return pyInfo;
 
-        if (testPythonInstallation("python", pyInfo))
+        if (testPythonInstallation(u"python"_qs, pyInfo))
             return pyInfo;
 
 #if defined(Q_OS_WIN)

src/base/utils/misc.cpp

@@ -265,7 +265,7 @@ QString Utils::Misc::friendlyUnit(const qint64 bytes, const bool isSpeed)
     if (!result)
         return QCoreApplication::translate("misc", "Unknown", "Unknown (size)");
     return Utils::String::fromDouble(result->value, friendlyUnitPrecision(result->unit))
-           + QString::fromUtf8(C_NON_BREAKING_SPACE)
+           + C_NON_BREAKING_SPACE
            + unitString(result->unit, isSpeed);
 }
 
@@ -354,9 +354,9 @@ bool Utils::Misc::isPreviewable(const Path &filePath)
 QString Utils::Misc::userFriendlyDuration(const qlonglong seconds, const qlonglong maxCap)
 {
     if (seconds < 0)
-        return QString::fromUtf8(C_INFINITY);
+        return C_INFINITY;
     if ((maxCap >= 0) && (seconds >= maxCap))
-        return QString::fromUtf8(C_INFINITY);
+        return C_INFINITY;
 
     if (seconds == 0)
         return u"0"_qs;

src/base/utils/net.cpp

@@ -94,7 +94,7 @@ namespace Utils
 
         QString subnetToString(const Subnet &subnet)
         {
-            return subnet.first.toString() + '/' + QString::number(subnet.second);
+            return subnet.first.toString() + u'/' + QString::number(subnet.second);
         }
 
         QHostAddress canonicalIPv6Addr(const QHostAddress &addr)