Handle UTF-8 in Qt streams in the Qt6-compatible way

apps/launcher/maindialog.cpp

@@ -7,13 +7,13 @@
 #include <QDebug>
 #include <QDir>
 #include <QMessageBox>
-#include <QTextCodec>
 #include <QTime>
 
 #include <boost/program_options/options_description.hpp>
 #include <boost/program_options/variables_map.hpp>
 #include <components/files/conversion.hpp>
 #include <components/files/qtconversion.hpp>
+#include <components/misc/utf8qtextstream.hpp>
 
 #include "advancedpage.hpp"
 #include "datafilespage.hpp"
@@ -323,7 +323,7 @@ bool Launcher::MainDialog::setupLauncherSettings()
                 return false;
             }
             QTextStream stream(&file);
-            stream.setCodec(QTextCodec::codecForName("UTF-8"));
+            ensureUtf8Encoding(stream);
 
             mLauncherSettings.readFile(stream);
         }
@@ -359,7 +359,7 @@ bool Launcher::MainDialog::setupGameSettings()
                 return {};
             }
             QTextStream stream(&file);
-            stream.setCodec(QTextCodec::codecForName("UTF-8"));
+            ensureUtf8Encoding(stream);
 
             (mGameSettings.*reader)(stream, ignoreContent);
             file.close();
@@ -559,7 +559,7 @@ bool Launcher::MainDialog::writeSettings()
 
     QTextStream stream(&file);
     stream.setDevice(&file);
-    stream.setCodec(QTextCodec::codecForName("UTF-8"));
+    ensureUtf8Encoding(stream);
 
     mLauncherSettings.writeFile(stream);
     file.close();

apps/wizard/inisettings.cpp

@@ -164,7 +164,11 @@ bool Wizard::IniSettings::writeFile(const QString& path, QTextStream& stream)
     if (file.open(QIODevice::ReadWrite | QIODevice::Truncate | QIODevice::Text))
     {
         QTextStream in(&file);
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
         in.setCodec(stream.codec());
+#else
+        in.setEncoding(stream.encoding());
+#endif
 
         // Write the updated buffer to an empty file
         in << buffer;

apps/wizard/mainwizard.cpp

@@ -5,9 +5,9 @@
 #include <QDir>
 #include <QMessageBox>
 #include <QProcess>
-#include <QTextCodec>
 
 #include <components/files/qtconversion.hpp>
+#include <components/misc/utf8qtextstream.hpp>
 #include <components/process/processinvoker.hpp>
 
 #include "componentselectionpage.hpp"
@@ -165,7 +165,7 @@ void Wizard::MainWizard::setupGameSettings()
             return;
         }
         QTextStream stream(&file);
-        stream.setCodec(QTextCodec::codecForName("UTF-8"));
+        ensureUtf8Encoding(stream);
 
         mGameSettings.readUserFile(stream);
     }
@@ -197,7 +197,7 @@ void Wizard::MainWizard::setupGameSettings()
                 return;
             }
             QTextStream stream(&file);
-            stream.setCodec(QTextCodec::codecForName("UTF-8"));
+            ensureUtf8Encoding(stream);
 
             mGameSettings.readFile(stream);
         }
@@ -233,7 +233,7 @@ void Wizard::MainWizard::setupLauncherSettings()
             return;
         }
         QTextStream stream(&file);
-        stream.setCodec(QTextCodec::codecForName("UTF-8"));
+        ensureUtf8Encoding(stream);
 
         mLauncherSettings.readFile(stream);
     }
@@ -460,7 +460,7 @@ void Wizard::MainWizard::writeSettings()
     }
 
     QTextStream stream(&file);
-    stream.setCodec(QTextCodec::codecForName("UTF-8"));
+    ensureUtf8Encoding(stream);
 
     mGameSettings.writeFile(stream);
     file.close();
@@ -486,7 +486,7 @@ void Wizard::MainWizard::writeSettings()
     }
 
     stream.setDevice(&file);
-    stream.setCodec(QTextCodec::codecForName("UTF-8"));
+    ensureUtf8Encoding(stream);
 
     mLauncherSettings.writeFile(stream);
     file.close();

components/CMakeLists.txt

@@ -197,7 +197,7 @@ add_component_dir (esm4
 )
 
 add_component_dir (misc
-    constants utf8stream resourcehelpers rng messageformatparser weakcache thread
+    constants utf8stream utf8qtextstream resourcehelpers rng messageformatparser weakcache thread
     compression osguservalues color tuplemeta tuplehelpers
     )
 

components/config/gamesettings.cpp

@@ -3,10 +3,10 @@
 
 #include <QDir>
 #include <QRegularExpression>
-#include <QTextCodec>
 
 #include <components/files/configurationmanager.hpp>
 #include <components/files/qtconversion.hpp>
+#include <components/misc/utf8qtextstream.hpp>
 
 const char Config::GameSettings::sArchiveKey[] = "fallback-archive";
 const char Config::GameSettings::sContentKey[] = "content";
@@ -232,7 +232,7 @@ bool Config::GameSettings::isOrderedLine(const QString& line)
 bool Config::GameSettings::writeFileWithComments(QFile& file)
 {
     QTextStream stream(&file);
-    stream.setCodec(QTextCodec::codecForName("UTF-8"));
+    ensureUtf8Encoding(stream);
 
     // slurp
     std::vector<QString> fileCopy;

components/misc/utf8qtextstream.hpp

@@ -0,0 +1,20 @@
+#ifndef MISC_UTF8QTEXTSTREAM_HPP
+#define MISC_UTF8QTEXTSTREAM_HPP
+
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+#include <QTextCodec>
+#endif
+#include <QTextStream>
+
+namespace
+{
+    void ensureUtf8Encoding(QTextStream& stream)
+    {
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
+        stream.setCodec(QTextCodec::codecForName("UTF-8"));
+#else
+        stream.setEncoding(QStringConverter::Utf8);
+#endif
+    }
+}
+#endif