1 files changed, 39 insertions, 22 deletions

diff --git a/src/corelib/kernel/qtranslator.cpp b/src/corelib/kernel/qtranslator.cpp
index f6f7ec12d1..5c4ebfedf1 100644
--- a/src/corelib/kernel/qtranslator.cpp
+++ b/src/corelib/kernel/qtranslator.cpp
@@ -22,7 +22,7 @@
 #include "qendian.h"
 #include "qresource.h"
 
-#if defined(Q_OS_UNIX) && !defined(Q_OS_NACL) && !defined(Q_OS_INTEGRITY)
+#if defined(Q_OS_UNIX) && !defined(Q_OS_INTEGRITY)
 #  define QT_USE_MMAP
 #  include "private/qcore_unix_p.h"
 // for mmap
@@ -39,8 +39,11 @@
 
 QT_BEGIN_NAMESPACE
 
+namespace {
 enum Tag { Tag_End = 1, Tag_SourceText16, Tag_Translation, Tag_Context16, Tag_Obsolete1,
            Tag_SourceText, Tag_Context, Tag_Comment, Tag_Obsolete2 };
+}
+
 /*
 $ mcookie
 3cb86418caef9c95cd211cbf60a1bddd
@@ -449,7 +452,7 @@ bool QTranslator::load(const QString & filename, const QString & directory,
     QString prefix;
     if (QFileInfo(filename).isRelative()) {
         prefix = directory;
-        if (prefix.length() && !prefix.endsWith(u'/'))
+        if (prefix.size() && !prefix.endsWith(u'/'))
             prefix += u'/';
     }
 
@@ -472,7 +475,7 @@ bool QTranslator::load(const QString & filename, const QString & directory,
             break;
 
         int rightmost = 0;
-        for (int i = 0; i < (int)delims.length(); i++) {
+        for (int i = 0; i < (int)delims.size(); i++) {
             int k = fname.lastIndexOf(delims[i]);
             if (k > rightmost)
                 rightmost = k;
@@ -627,7 +630,7 @@ static QString find_translation(const QLocale & locale,
     // "prefix_en_us.qm" won't be found under the "en_US" locale. Note
     // that the Qt resource system is always case-sensitive, even on
     // Windows (in other words: this codepath is *not* UNIX-only).
-    QStringList languages = locale.uiLanguages();
+    QStringList languages = locale.uiLanguages(QLocale::TagSeparator::Underscore);
     for (int i = languages.size()-1; i >= 0; --i) {
         QString lang = languages.at(i);
         QString lowerLang = lang.toLower();
@@ -635,27 +638,41 @@ static QString find_translation(const QLocale & locale,
             languages.insert(i + 1, lowerLang);
     }
 
-    for (QString localeName : qAsConst(languages)) {
-        localeName.replace(u'-', u'_');
-
-        // try the complete locale name first and progressively truncate from
-        // the end until a matching language tag is found (with or without suffix)
+    QStringList candidates;
+    // assume 3 segments for each entry
+    candidates.reserve(languages.size() * 3);
+    for (QStringView language : std::as_const(languages)) {
+        // for each language, add versions without territory and script
         for (;;) {
-            realname += localeName + suffixOrDotQM;
-            if (is_readable_file(realname))
-                return realname;
+            candidates += language.toString();
+            int rightmost = language.lastIndexOf(u'_');
+            if (rightmost <= 0)
+                break;
+            language.truncate(rightmost);
+        }
+    }
 
-            realname.truncate(realNameBaseSize + localeName.size());
-            if (is_readable_file(realname))
-                return realname;
+    // now sort the list of candidates
+    std::sort(candidates.begin(), candidates.end(), [](const auto &lhs, const auto &rhs){
+        const auto rhsSegments = rhs.count(u'_');
+        const auto lhsSegments = lhs.count(u'_');
+        // candidates with more segments come first
+        if (rhsSegments != lhsSegments)
+            return rhsSegments < lhsSegments;
+        // candidates with same number of segments are sorted alphanumerically
+        return lhs < rhs;
+    });
+
+    for (const QString &localeName : std::as_const(candidates)) {
+        realname += localeName + suffixOrDotQM;
+        if (is_readable_file(realname))
+            return realname;
 
-            realname.truncate(realNameBaseSize);
+        realname.truncate(realNameBaseSize + localeName.size());
+        if (is_readable_file(realname))
+            return realname;
 
-            int rightmost = localeName.lastIndexOf(u'_');
-            if (rightmost <= 0)
-                break; // no truncations anymore, break
-            localeName.truncate(rightmost);
-        }
+        realname.truncate(realNameBaseSize);
     }
 
     const int realNameBaseSizeFallbacks = path.size() + filename.size();
@@ -914,7 +931,7 @@ end:
     if (!tn)
         return QString();
     QString str(tn_length / 2, Qt::Uninitialized);
-    qFromBigEndian<ushort>(tn, str.length(), str.data());
+    qFromBigEndian<char16_t>(tn, str.size(), str.data());
     return str;
 }