Linguist: Refactor iterators

Use more const iterators.
Fix mixing const iterators with non-const iterators.
Use auto for iterators wherever easily possible.

Change-Id: Ib6e73319971396e47bb0b0f5c252b8cf246de008
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

14 files changed, 82 insertions, 100 deletions

diff --git a/src/linguist/linguist/formpreviewview.cpp b/src/linguist/linguist/formpreviewview.cpp
index 2446e0097..8aed545da 100644
--- a/src/linguist/linguist/formpreviewview.cpp
+++ b/src/linguist/linguist/formpreviewview.cpp
@@ -207,8 +207,8 @@ static void buildTargets(QObject *o, TargetsHash *targets)
 
 static void destroyTargets(TargetsHash *targets)
 {
-    for (TargetsHash::ConstIterator it = targets->cbegin(), end = targets->cend(); it != end; ++it)
-        for (const TranslatableEntry &target : *it)
+    for (const auto &targetList : qAsConst(*targets))
+        for (const TranslatableEntry &target : targetList)
             if (target.type == TranslatableProperty)
                 delete target.prop.name;
     targets->clear();
@@ -554,7 +554,7 @@ void FormPreviewView::setSourceContext(int model, MessageItem *messageItem)
     tsv.setQualifier(messageItem->comment().toUtf8());
     m_highlights = m_targets.value(tsv);
     if (m_lastModel != model) {
-        for (TargetsHash::Iterator it = m_targets.begin(), end = m_targets.end(); it != end; ++it)
+        for (auto it = m_targets.cbegin(), end = m_targets.cend(); it != end; ++it)
             retranslateTargets(*it, it.key(), m_dataModel->model(model), m_lastClassName);
         m_lastModel = model;
     } else {
diff --git a/src/linguist/lprodump/main.cpp b/src/linguist/lprodump/main.cpp
index 85eedd8e4..9ef5faa9c 100644
--- a/src/linguist/lprodump/main.cpp
+++ b/src/linguist/lprodump/main.cpp
@@ -236,7 +236,7 @@ static QStringList getSources(const ProFileEvaluator &visitor, const QString &pr
     for (const QString &ex : excludes) {
         // TODO: take advantage of the file list being sorted
         QRegularExpression rx(QRegularExpression::wildcardToRegularExpression(ex));
-        for (QStringList::Iterator it = sourceFiles.begin(); it != sourceFiles.end(); ) {
+        for (auto it = sourceFiles.begin(); it != sourceFiles.end(); ) {
             if (rx.match(*it).hasMatch())
                 it = sourceFiles.erase(it);
             else
@@ -262,7 +262,7 @@ static void excludeProjects(const ProFileEvaluator &visitor, QStringList *subPro
 {
     for (const QString &ex : visitor.values(QLatin1String("TR_EXCLUDE"))) {
         QRegularExpression rx(QRegularExpression::wildcardToRegularExpression(ex));
-        for (QStringList::Iterator it = subProjects->begin(); it != subProjects->end(); ) {
+        for (auto it = subProjects->begin(); it != subProjects->end(); ) {
             if (rx.match(*it).hasMatch())
                 it = subProjects->erase(it);
             else
diff --git a/src/linguist/lupdate/cpp.cpp b/src/linguist/lupdate/cpp.cpp
index bbab74649..ede034353 100644
--- a/src/linguist/lupdate/cpp.cpp
+++ b/src/linguist/lupdate/cpp.cpp
@@ -1023,7 +1023,7 @@ bool CppParser::qualifyOneCallbackOwn(const Namespace *ns, void *context) const
         *data->resolved << data->segment;
         return true;
     }
-    QHash<HashString, NamespaceList>::ConstIterator nsai = ns->aliases.constFind(data->segment);
+    auto nsai = ns->aliases.constFind(data->segment);
     if (nsai != ns->aliases.constEnd()) {
         const NamespaceList &nsl = *nsai;
         if (nsl.last().value().isEmpty()) { // Delayed alias resolution
@@ -2210,7 +2210,7 @@ const ParseResults *CppParser::recordResults(bool isHeader)
             && results->rootNamespace.aliases.isEmpty()
             && results->rootNamespace.usings.isEmpty()) {
             // This is a forwarding header. Slash it.
-            pr = *results->includes.begin();
+            pr = *results->includes.cbegin();
             delete results;
         } else {
             results->fileId = nextFileId++;
diff --git a/src/linguist/lupdate/cpp_clang.cpp b/src/linguist/lupdate/cpp_clang.cpp
index 8bab9dba6..951714c7d 100644
--- a/src/linguist/lupdate/cpp_clang.cpp
+++ b/src/linguist/lupdate/cpp_clang.cpp
@@ -128,8 +128,8 @@ void ClangCppParser::loadCPP(Translator &translator, const QStringList &files, C
             sources.push_back(filename.toStdString());
         }
     }
-    sourcesPP.insert(sourcesPP.end(), sources.begin(), sources.end());
-    sourcesAst.insert(sourcesAst.end(), sources.begin(), sources.end());
+    sourcesPP.insert(sourcesPP.cend(), sources.cbegin(), sources.cend());
+    sourcesAst.insert(sourcesAst.cend(), sources.cbegin(), sources.cend());
 
     int argc = 4;
     // NEED 2 empty one to start!!! otherwise: LLVM::ERROR
diff --git a/src/linguist/lupdate/main.cpp b/src/linguist/lupdate/main.cpp
index b8a8cf121..055a1b7ed 100644
--- a/src/linguist/lupdate/main.cpp
+++ b/src/linguist/lupdate/main.cpp
@@ -40,7 +40,6 @@
 
 #include <QtCore/QCoreApplication>
 #include <QtCore/QDir>
-#include <QtCore/QDirIterator>
 #include <QtCore/QFile>
 #include <QtCore/QFileInfo>
 #include <QtCore/QLibraryInfo>
@@ -91,9 +90,8 @@ int TrFunctionAliasManager::trFunctionByName(const QString &trFunctionName) cons
 {
     ensureTrFunctionHashUpdated();
     // this function needs to be fast
-    const QHash<QString, TrFunction>::const_iterator it
-        = m_nameToTrFunctionMap.find(trFunctionName);
-    return it == m_nameToTrFunctionMap.end() ? -1 : *it;
+    const auto it = m_nameToTrFunctionMap.constFind(trFunctionName);
+    return it == m_nameToTrFunctionMap.cend() ? -1 : *it;
 }
 
 void TrFunctionAliasManager::modifyAlias(int trFunction, const QString &alias, Operation op)
@@ -500,26 +498,26 @@ static void processSources(Translator &fetchedTor,
     bool requireQmlSupport = false;
 #endif
     QStringList sourceFilesCpp;
-    for (QStringList::const_iterator it = sourceFiles.begin(); it != sourceFiles.end(); ++it) {
-        if (it->endsWith(QLatin1String(".java"), Qt::CaseInsensitive))
-            loadJava(fetchedTor, *it, cd);
-        else if (it->endsWith(QLatin1String(".ui"), Qt::CaseInsensitive)
-                 || it->endsWith(QLatin1String(".jui"), Qt::CaseInsensitive))
-            loadUI(fetchedTor, *it, cd);
+    for (const auto &sourceFile : sourceFiles) {
+        if (sourceFile.endsWith(QLatin1String(".java"), Qt::CaseInsensitive))
+            loadJava(fetchedTor, sourceFile, cd);
+        else if (sourceFile.endsWith(QLatin1String(".ui"), Qt::CaseInsensitive)
+                 || sourceFile.endsWith(QLatin1String(".jui"), Qt::CaseInsensitive))
+            loadUI(fetchedTor, sourceFile, cd);
 #ifndef QT_NO_QML
-        else if (it->endsWith(QLatin1String(".js"), Qt::CaseInsensitive)
-                 || it->endsWith(QLatin1String(".qs"), Qt::CaseInsensitive))
-            loadQScript(fetchedTor, *it, cd);
-        else if (it->endsWith(QLatin1String(".qml"), Qt::CaseInsensitive))
-            loadQml(fetchedTor, *it, cd);
+        else if (sourceFile.endsWith(QLatin1String(".js"), Qt::CaseInsensitive)
+                 || sourceFile.endsWith(QLatin1String(".qs"), Qt::CaseInsensitive))
+            loadQScript(fetchedTor, sourceFile, cd);
+        else if (sourceFile.endsWith(QLatin1String(".qml"), Qt::CaseInsensitive))
+            loadQml(fetchedTor, sourceFile, cd);
 #else
-        else if (it->endsWith(QLatin1String(".qml"), Qt::CaseInsensitive)
-                 || it->endsWith(QLatin1String(".js"), Qt::CaseInsensitive)
-                 || it->endsWith(QLatin1String(".qs"), Qt::CaseInsensitive))
+        else if (sourceFile.endsWith(QLatin1String(".qml"), Qt::CaseInsensitive)
+                 || sourceFile.endsWith(QLatin1String(".js"), Qt::CaseInsensitive)
+                 || sourceFile.endsWith(QLatin1String(".qs"), Qt::CaseInsensitive))
             requireQmlSupport = true;
 #endif // QT_NO_QML
-        else if (!processTs(fetchedTor, *it, cd))
-            sourceFilesCpp << *it;
+        else if (!processTs(fetchedTor, sourceFile, cd))
+            sourceFilesCpp << sourceFile;
     }
 
 #ifdef QT_NO_QML
diff --git a/src/linguist/lupdate/merge.cpp b/src/linguist/lupdate/merge.cpp
index 8473e332a..9db8826c8 100644
--- a/src/linguist/lupdate/merge.cpp
+++ b/src/linguist/lupdate/merge.cpp
@@ -230,8 +230,7 @@ int applyNumberHeuristic(Translator &tor)
             TranslatorMessage &msg = tor.message(i);
             const QString &key = zeroKey(msg.sourceText());
             if (!key.isEmpty()) {
-                QMap<QString, QPair<QString, QString> >::ConstIterator t =
-                        translated.constFind(key);
+                const auto t = translated.constFind(key);
                 if (t != translated.constEnd() && t->first != msg.sourceText()) {
                     msg.setTranslation(translationAttempt(t->second, t->first,
                                                           msg.sourceText()));
@@ -268,7 +267,7 @@ int applySameTextHeuristic(Translator &tor)
                 untranslated[i] = true;
         } else {
             const QString &key = msg.sourceText();
-            QMap<QString, QStringList>::ConstIterator t = translated.constFind(key);
+            const auto t = translated.constFind(key);
             if (t != translated.constEnd()) {
                 /*
                   The same source text is translated at least two
@@ -287,7 +286,7 @@ int applySameTextHeuristic(Translator &tor)
     for (int i = 0; i < tor.messageCount(); ++i) {
         if (untranslated[i]) {
             TranslatorMessage &msg = tor.message(i);
-            QMap<QString, QStringList>::ConstIterator t = translated.constFind(msg.sourceText());
+            const auto t = translated.constFind(msg.sourceText());
             if (t != translated.constEnd()) {
                 msg.setTranslations(*t);
                 ++inserted;
diff --git a/src/linguist/lupdate/synchronized.h b/src/linguist/lupdate/synchronized.h
index 8fe5d8ed0..5bf621a30 100644
--- a/src/linguist/lupdate/synchronized.h
+++ b/src/linguist/lupdate/synchronized.h
@@ -61,7 +61,7 @@ public:
     {
         QMutexLocker lock(&m_mutex);
         if (!m_vector.empty()) {
-            m_vector.insert(m_vector.end(), std::make_move_iterator(values.begin()),
+            m_vector.insert(m_vector.cend(), std::make_move_iterator(values.begin()),
                 std::make_move_iterator(values.end()));
         } else {
             m_vector = std::move(values);
diff --git a/src/linguist/shared/po.cpp b/src/linguist/shared/po.cpp
index 221d84853..d9aa24bbd 100644
--- a/src/linguist/shared/po.cpp
+++ b/src/linguist/shared/po.cpp
@@ -534,9 +534,7 @@ bool loadPO(Translator &translator, QIODevice &dev, ConversionData &cd)
                     extras[QLatin1String("po-header_comment")] =
                             QByteArrayList_join(lines.mid(0, lastCmtLine + 1), '\n');
                 }
-                for (QHash<QString, QByteArray>::ConstIterator it = extras.constBegin(),
-                                                               end = extras.constEnd();
-                     it != end; ++it)
+                for (auto it = extras.cbegin(), end = extras.cend(); it != end; ++it)
                     translator.setExtra(it.key(), toUnicode(it.value()));
                 item = PoItem();
                 continue;
@@ -611,9 +609,8 @@ bool loadPO(Translator &translator, QIODevice &dev, ConversionData &cd)
                     if (flags.removeOne(QLatin1String("fuzzy")))
                         item.isFuzzy = true;
                     flags.removeOne(QLatin1String("qt-format"));
-                    TranslatorMessage::ExtraData::const_iterator it =
-                            item.extra.find(QLatin1String("po-flags"));
-                    if (it != item.extra.end())
+                    const auto it = item.extra.constFind(QLatin1String("po-flags"));
+                    if (it != item.extra.cend())
                         flags.prepend(*it);
                     if (!flags.isEmpty())
                         item.extra[QLatin1String("po-flags")] = flags.join(QLatin1String(", "));
@@ -806,9 +803,8 @@ bool savePO(const Translator &translator, QIODevice &dev, ConversionData &)
         if ((msg.type() == TranslatorMessage::Unfinished
              || msg.type() == TranslatorMessage::Obsolete) && msg.isTranslated())
             flags.append(QLatin1String("fuzzy"));
-        TranslatorMessage::ExtraData::const_iterator itr =
-                msg.extras().find(QLatin1String("po-flags"));
-        if (itr != msg.extras().end()) {
+        const auto itr = msg.extras().constFind(QLatin1String("po-flags"));
+        if (itr != msg.extras().cend()) {
             const QStringList atoms = itr->split(QLatin1String(", "));
             for (const QString &atom : atoms)
                 if (atom.endsWith(str_format)) {
diff --git a/src/linguist/shared/profileevaluator.cpp b/src/linguist/shared/profileevaluator.cpp
index f89ff8eef..77059fa94 100644
--- a/src/linguist/shared/profileevaluator.cpp
+++ b/src/linguist/shared/profileevaluator.cpp
@@ -219,9 +219,7 @@ void ProFileEvaluator::setCumulative(bool on)
 void ProFileEvaluator::setExtraVars(const QHash<QString, QStringList> &extraVars)
 {
     ProValueMap map;
-    QHash<QString, QStringList>::const_iterator it = extraVars.constBegin();
-    QHash<QString, QStringList>::const_iterator end = extraVars.constEnd();
-    for ( ; it != end; ++it)
+    for (auto it = extraVars.cbegin(), end = extraVars.cend() ; it != end; ++it)
         map.insert(ProKey(it.key()), ProStringList(it.value()));
     d->setExtraVars(map);
 }
diff --git a/src/linguist/shared/qm.cpp b/src/linguist/shared/qm.cpp
index c638e4e73..6eb9c874d 100644
--- a/src/linguist/shared/qm.cpp
+++ b/src/linguist/shared/qm.cpp
@@ -293,7 +293,7 @@ void Releaser::squeeze(TranslatorSaveMode mode)
     if (m_messages.isEmpty() && mode == SaveEverything)
         return;
 
-    QMap<ByteTranslatorMessage, void *> messages = m_messages;
+    const auto messages = m_messages;
 
     // re-build contents
     m_messageArray.clear();
@@ -304,13 +304,11 @@ void Releaser::squeeze(TranslatorSaveMode mode)
     QMap<Offset, void *> offsets;
 
     QDataStream ms(&m_messageArray, QIODevice::WriteOnly);
-    QMap<ByteTranslatorMessage, void *>::const_iterator it, next;
     int cpPrev = 0, cpNext = 0;
-    for (it = messages.constBegin(); it != messages.constEnd(); ++it) {
+    for (auto it = messages.cbegin(), end = messages.cend(); it != end; ++it) {
         cpPrev = cpNext;
-        next = it;
-        ++next;
-        if (next == messages.constEnd())
+        const auto next = std::next(it);
+        if (next == end)
             cpNext = 0;
         else
             cpNext = commonPrefix(it.key(), next.key());
@@ -318,10 +316,9 @@ void Releaser::squeeze(TranslatorSaveMode mode)
         writeMessage(it.key(), ms, mode, Prefix(qMax(cpPrev, cpNext + 1)));
     }
 
-    QMap<Offset, void *>::Iterator offset;
-    offset = offsets.begin();
+    auto offset = offsets.cbegin();
     QDataStream ds(&m_offsetArray, QIODevice::WriteOnly);
-    while (offset != offsets.end()) {
+    while (offset != offsets.cend()) {
         Offset k = offset.key();
         ++offset;
         ds << quint32(k.h) << quint32(k.o);
@@ -329,7 +326,7 @@ void Releaser::squeeze(TranslatorSaveMode mode)
 
     if (mode == SaveStripped) {
         QMap<QByteArray, int> contextSet;
-        for (it = messages.constBegin(); it != messages.constEnd(); ++it)
+        for (auto it = messages.cbegin(), end = messages.cend(); it != end; ++it)
             ++contextSet[it.key().context()];
 
         quint16 hTableSize;
@@ -341,8 +338,7 @@ void Releaser::squeeze(TranslatorSaveMode mode)
             hTableSize = (contextSet.size() < 10000) ? 15013 : 3 * contextSet.size() / 2;
 
         QMultiMap<int, QByteArray> hashMap;
-        QMap<QByteArray, int>::const_iterator c;
-        for (c = contextSet.constBegin(); c != contextSet.constEnd(); ++c)
+        for (auto c = contextSet.cbegin(), end = contextSet.cend(); c != end; ++c)
             hashMap.insert(elfHash(c.key()) % hTableSize, c.key());
 
         /*
@@ -378,7 +374,7 @@ void Releaser::squeeze(TranslatorSaveMode mode)
         t << quint16(0); // the entry at offset 0 cannot be used
         uint upto = 2;
 
-        QMultiMap<int, QByteArray>::const_iterator entry = hashMap.constBegin();
+        auto entry = hashMap.constBegin();
         while (entry != hashMap.constEnd()) {
             int i = entry.key();
             hTable[i] = quint16(upto >> 1);
diff --git a/src/linguist/shared/translator.cpp b/src/linguist/shared/translator.cpp
index 7fb464e6b..ced5df322 100644
--- a/src/linguist/shared/translator.cpp
+++ b/src/linguist/shared/translator.cpp
@@ -383,12 +383,12 @@ int Translator::find(const QString &context,
     const QString &comment, const TranslatorMessage::References &refs) const
 {
     if (!refs.isEmpty()) {
-        for (TMM::ConstIterator it = m_messages.constBegin(); it != m_messages.constEnd(); ++it) {
+        for (auto it = m_messages.cbegin(), end = m_messages.cend(); it != end; ++it) {
             if (it->context() == context && it->comment() == comment) {
-                for (const TranslatorMessage::Reference &itref : it->allReferences()) {
-                    for (const TranslatorMessage::Reference &ref : refs) {
+                for (const auto &itref : it->allReferences()) {
+                    for (const auto &ref : refs) {
                         if (itref == ref)
-                            return it - m_messages.constBegin();
+                            return it - m_messages.cbegin();
                     }
                 }
             }
@@ -405,7 +405,7 @@ int Translator::find(const QString &context) const
 
 void Translator::stripObsoleteMessages()
 {
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end(); )
+    for (auto it = m_messages.begin(); it != m_messages.end(); )
         if (it->type() == TranslatorMessage::Obsolete || it->type() == TranslatorMessage::Vanished)
             it = m_messages.erase(it);
         else
@@ -415,7 +415,7 @@ void Translator::stripObsoleteMessages()
 
 void Translator::stripFinishedMessages()
 {
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end(); )
+    for (auto it = m_messages.begin(); it != m_messages.end(); )
         if (it->type() == TranslatorMessage::Finished)
             it = m_messages.erase(it);
         else
@@ -425,7 +425,7 @@ void Translator::stripFinishedMessages()
 
 void Translator::stripUntranslatedMessages()
 {
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end(); )
+    for (auto it = m_messages.begin(); it != m_messages.end(); )
         if (!it->isTranslated())
             it = m_messages.erase(it);
         else
@@ -433,20 +433,18 @@ void Translator::stripUntranslatedMessages()
     m_indexOk = false;
 }
 
-bool Translator::translationsExist()
+bool Translator::translationsExist() const
 {
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end(); ) {
-        if (it->isTranslated())
+    for (const auto &message : m_messages) {
+        if (message.isTranslated())
             return true;
-        else
-            ++it;
     }
     return false;
 }
 
 void Translator::stripEmptyContexts()
 {
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end();)
+    for (auto it = m_messages.begin(); it != m_messages.end(); )
         if (it->sourceText() == QLatin1String(ContextComment))
             it = m_messages.erase(it);
         else
@@ -456,7 +454,7 @@ void Translator::stripEmptyContexts()
 
 void Translator::stripNonPluralForms()
 {
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end(); )
+    for (auto it = m_messages.begin(); it != m_messages.end(); )
         if (!it->isPlural())
             it = m_messages.erase(it);
         else
@@ -466,7 +464,7 @@ void Translator::stripNonPluralForms()
 
 void Translator::stripIdenticalSourceTranslations()
 {
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end(); ) {
+    for (auto it = m_messages.begin(); it != m_messages.end(); ) {
         // we need to have just one translation, and it be equal to the source
         if (it->translations().count() == 1 && it->translation() == it->sourceText())
             it = m_messages.erase(it);
@@ -478,21 +476,21 @@ void Translator::stripIdenticalSourceTranslations()
 
 void Translator::dropTranslations()
 {
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end(); ++it) {
-        if (it->type() == TranslatorMessage::Finished)
-            it->setType(TranslatorMessage::Unfinished);
-        it->setTranslation(QString());
+    for (auto &message : m_messages) {
+        if (message.type() == TranslatorMessage::Finished)
+            message.setType(TranslatorMessage::Unfinished);
+        message.setTranslation(QString());
     }
 }
 
 void Translator::dropUiLines()
 {
-    QString uiXt = QLatin1String(".ui");
-    QString juiXt = QLatin1String(".jui");
-    for (TMM::Iterator it = m_messages.begin(); it != m_messages.end(); ++it) {
+    const QString uiXt = QLatin1String(".ui");
+    const QString juiXt = QLatin1String(".jui");
+    for (auto &message : m_messages) {
         QHash<QString, int> have;
         QList<TranslatorMessage::Reference> refs;
-        for (const TranslatorMessage::Reference &itref : it->allReferences()) {
+        for (const auto &itref : message.allReferences()) {
             const QString &fn = itref.fileName();
             if (fn.endsWith(uiXt) || fn.endsWith(juiXt)) {
                 if (++have[fn] == 1)
@@ -501,7 +499,7 @@ void Translator::dropUiLines()
                 refs.append(itref);
             }
         }
-        it->setReferences(refs);
+        message.setReferences(refs);
     }
 }
 
@@ -578,8 +576,7 @@ Translator::Duplicates Translator::resolveDuplicates()
         int oi;
         QSet<int> *pDup;
         if (!msg.id().isEmpty()) {
-            QHash<TranslatorMessageIdPtr, int>::ConstIterator it =
-                    idRefs.constFind(TranslatorMessageIdPtr(msg));
+            const auto it = idRefs.constFind(TranslatorMessageIdPtr(msg));
             if (it != idRefs.constEnd()) {
                 oi = *it;
                 omsg = &m_messages[oi];
@@ -588,8 +585,7 @@ Translator::Duplicates Translator::resolveDuplicates()
             }
         }
         {
-            QHash<TranslatorMessageContentPtr, int>::ConstIterator it =
-                    contentRefs.constFind(TranslatorMessageContentPtr(msg));
+            const auto it = contentRefs.constFind(TranslatorMessageContentPtr(msg));
             if (it != contentRefs.constEnd()) {
                 oi = *it;
                 omsg = &m_messages[oi];
@@ -649,8 +645,7 @@ void Translator::reportDuplicates(const Duplicates &dupes,
 // Used by lupdate to be able to search using absolute paths during merging
 void Translator::makeFileNamesAbsolute(const QDir &originalPath)
 {
-    for (TMM::iterator it = m_messages.begin(); it != m_messages.end(); ++it) {
-        TranslatorMessage &msg = *it;
+    for (auto &msg : m_messages) {
         const TranslatorMessage::References refs = msg.allReferences();
         msg.setReferences(TranslatorMessage::References());
         for (const TranslatorMessage::Reference &ref : refs) {
diff --git a/src/linguist/shared/translator.h b/src/linguist/shared/translator.h
index 285146813..80bb201e1 100644
--- a/src/linguist/shared/translator.h
+++ b/src/linguist/shared/translator.h
@@ -139,7 +139,7 @@ public:
     void dropTranslations();
     void dropUiLines();
     void makeFileNamesAbsolute(const QDir &originalPath);
-    bool translationsExist();
+    bool translationsExist() const;
 
     struct Duplicates { QSet<int> byId, byContents; };
     Duplicates resolveDuplicates();
diff --git a/src/linguist/shared/ts.cpp b/src/linguist/shared/ts.cpp
index 9a6f8b2b7..a5daf7c90 100644
--- a/src/linguist/shared/ts.cpp
+++ b/src/linguist/shared/ts.cpp
@@ -470,7 +470,7 @@ static void writeExtras(QTextStream &t, const char *indent,
                         const TranslatorMessage::ExtraData &extras, QRegularExpression drops)
 {
     QStringList outs;
-    for (Translator::ExtraData::ConstIterator it = extras.begin(); it != extras.end(); ++it) {
+    for (auto it = extras.cbegin(), end = extras.cend(); it != end; ++it) {
         if (!drops.match(it.key()).hasMatch()) {
             outs << (QStringLiteral("<extra-") + it.key() + QLatin1Char('>')
                      + protect(it.value())
diff --git a/src/linguist/shared/xliff.cpp b/src/linguist/shared/xliff.cpp
index 71b3305e3..ef380939e 100644
--- a/src/linguist/shared/xliff.cpp
+++ b/src/linguist/shared/xliff.cpp
@@ -177,7 +177,7 @@ static QString protect(const QString &str, bool makePhs = true)
 static void writeExtras(QTextStream &ts, int indent,
                         const TranslatorMessage::ExtraData &extras, QRegularExpression drops)
 {
-    for (Translator::ExtraData::ConstIterator it = extras.begin(); it != extras.end(); ++it) {
+    for (auto it = extras.cbegin(), end = extras.cend(); it != end; ++it) {
         if (!drops.match(it.key()).hasMatch()) {
             writeIndent(ts, indent);
             ts << "<trolltech:" << it.key() << '>'
@@ -238,15 +238,16 @@ static void writeTransUnits(QTextStream &ts, const TranslatorMessage &msg, const
     QString msgidstr = !msg.id().isEmpty() ? msg.id() : QString::fromLatin1("_msg%1").arg(++msgid);
 
     QStringList translns = msg.translations();
-    QHash<QString, QString>::const_iterator it;
     QString pluralStr;
     QStringList sources(msg.sourceText());
-    if ((it = msg.extras().find(QString::fromLatin1("po-msgid_plural"))) != msg.extras().end())
+    const auto &extras = msg.extras();
+    const auto extrasEnd = extras.cend();
+    if (const auto it = extras.constFind(QString::fromLatin1("po-msgid_plural")); it != extrasEnd)
         sources.append(*it);
     QStringList oldsources;
     if (!msg.oldSourceText().isEmpty())
         oldsources.append(msg.oldSourceText());
-    if ((it = msg.extras().find(QString::fromLatin1("po-old_msgid_plural"))) != msg.extras().end()) {
+    if (const auto it = extras.constFind(QString::fromLatin1("po-old_msgid_plural")); it != extrasEnd) {
         if (oldsources.isEmpty()) {
             if (sources.count() == 2)
                 oldsources.append(QString());
@@ -256,10 +257,9 @@ static void writeTransUnits(QTextStream &ts, const TranslatorMessage &msg, const
         oldsources.append(*it);
     }
 
-    QStringList::const_iterator
-        srcit = sources.begin(), srcend = sources.end(),
-        oldsrcit = oldsources.begin(), oldsrcend = oldsources.end(),
-        transit = translns.begin(), transend = translns.end();
+    auto srcit = sources.cbegin(), srcend = sources.cend(),
+         oldsrcit = oldsources.cbegin(), oldsrcend = oldsources.cend(),
+         transit = translns.cbegin(), transend = translns.cend();
     int plural = 0;
     QString source;
     while (srcit != srcend || oldsrcit != oldsrcend || transit != transend) {
@@ -795,7 +795,7 @@ bool saveXLIFF(const Translator &translator, QIODevice &dev, ConversionData &cd)
     for (const QString &fn : qAsConst(fileOrder)) {
         writeIndent(ts, indent);
         ts << "<file original=\"" << fn << "\""
-            << " datatype=\"" << dataType(messageOrder[fn].begin()->first()) << "\""
+            << " datatype=\"" << dataType(messageOrder[fn].cbegin()->first()) << "\""
             << " source-language=\"" << sourceLanguageCode.toLatin1() << "\""
             << " target-language=\"" << languageCode.toLatin1() << "\""
             << "><body>\n";