Prefer rvalue versions of toLatin() and toUtf8()

... to re-use existing buffers.

Change-Id: I7c42529b8cd4400520a59e658ab76f4f8e965cd4
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/io/qsettings_mac.cpp

@@ -211,7 +211,7 @@ static QCFType<CFPropertyListRef> macValue(const QVariant &value)
     default:
         QString string = QSettingsPrivate::variantToString(value);
         if (string.contains(QChar::Null))
-            result = string.toUtf8().toCFData();
+            result = std::move(string).toUtf8().toCFData();
         else
             result = string.toCFString();
     }

src/corelib/io/qurl.cpp

@@ -3418,8 +3418,7 @@ QUrl QUrl::adjusted(QUrl::FormattingOptions options) const
 QByteArray QUrl::toEncoded(FormattingOptions options) const
 {
     options &= ~(FullyDecoded | FullyEncoded);
-    QString stringForm = toString(options | FullyEncoded);
-    return stringForm.toLatin1();
+    return toString(options | FullyEncoded).toLatin1();
 }
 
 /*!
@@ -3536,8 +3535,7 @@ QString QUrl::fromAce(const QByteArray &domain)
 */
 QByteArray QUrl::toAce(const QString &domain)
 {
-    QString result = qt_ACE_do(domain, ToAceOnly, ForbidLeadingDot /*FIXME: make configurable*/);
-    return result.toLatin1();
+    return qt_ACE_do(domain, ToAceOnly, ForbidLeadingDot /*FIXME: make configurable*/).toLatin1();
 }
 
 /*!

src/corelib/tools/qlocale_win.cpp

@@ -1037,7 +1037,7 @@ static QString winIso639LangName(LPWSTR id)
     if (!lang_code.isEmpty()) {
         const char *endptr;
         bool ok;
-        QByteArray latin1_lang_code = lang_code.toLatin1();
+        QByteArray latin1_lang_code = std::move(lang_code).toLatin1();
         int i = qstrtoull(latin1_lang_code, &endptr, 16, &ok);
         if (ok && *endptr == '\0') {
             switch (i) {
@@ -1120,15 +1120,12 @@ static QByteArray getWinLocaleName(LPWSTR id)
         id = lcName;
     }
 #endif // Q_OS_WINRT
-    QString resultuage = winIso639LangName(id);
+    QString resultusage = winIso639LangName(id);
     QString country = winIso3116CtryName(id);
-    result = resultuage.toLatin1();
-    if (!country.isEmpty()) {
-        result += '_';
-        result += country.toLatin1();
-    }
+    if (!country.isEmpty())
+        resultusage += QLatin1Char('_') + country;
 
-    return result;
+    return std::move(resultusage).toLatin1();
 }
 
 Q_CORE_EXPORT QLocale qt_localeFromLCID(LCID id)

src/corelib/tools/qregularexpression.cpp

@@ -1674,7 +1674,7 @@ QString QRegularExpression::errorString() const
         } while (errorStringLength < 0);
         errorString.resize(errorStringLength);
 
-        return QCoreApplication::translate("QRegularExpression", errorString.toLatin1().constData());
+        return QCoreApplication::translate("QRegularExpression", std::move(errorString).toLatin1().constData());
     }
     return QCoreApplication::translate("QRegularExpression", "no error");
 }

src/corelib/tools/qtimezoneprivate_icu.cpp

@@ -98,7 +98,7 @@ static QByteArray ucalDefaultTimeZoneId()
     // If successful on first or second go, resize and return
     if (U_SUCCESS(status)) {
         result.resize(size);
-        return result.toUtf8();
+        return std::move(result).toUtf8();
     }
 
     return QByteArray();

src/corelib/tools/qtimezoneprivate_win.cpp

@@ -299,7 +299,7 @@ static QByteArray windowsSystemZoneId()
         id = readRegistryString(key, L"TimeZoneKeyName");
         RegCloseKey(key);
         if (!id.isEmpty())
-            return id.toUtf8();
+            return std::move(id).toUtf8();
     }
 
     // On XP we have to iterate over the zones until we find a match on

src/network/access/qhttpnetworkconnection.cpp

@@ -327,7 +327,7 @@ void QHttpNetworkConnectionPrivate::prepareRequest(HttpMessagePair &messagePair)
             acceptLanguage = systemLocale + QLatin1String(",*");
         else
             acceptLanguage = systemLocale + QLatin1String(",en,*");
-        request.setHeaderField("Accept-Language", acceptLanguage.toLatin1());
+        request.setHeaderField("Accept-Language", std::move(acceptLanguage).toLatin1());
     }
 
     // set the User Agent

src/network/access/qhttpthreaddelegate.cpp

@@ -169,7 +169,7 @@ static QByteArray makeCacheKey(QUrl &url, QNetworkProxy *proxy)
     Q_UNUSED(proxy)
 #endif
 
-    return "http-connection:" + result.toLatin1();
+    return "http-connection:" + std::move(result).toLatin1();
 }
 
 class QNetworkAccessCachedHttpConnection: public QHttpNetworkConnection,

src/plugins/platforms/windows/qwindowsmime.cpp

@@ -717,7 +717,7 @@ QVariant QWindowsMimeText::convertToMime(const QString &mime, LPDATAOBJECT pData
         if (preferredType == QVariant::String)
             ret = str;
         else
-            ret = str.toUtf8();
+            ret = std::move(str).toUtf8();
     }
     qCDebug(lcQpaMime) << __FUNCTION__ << ret;
     return ret;

src/plugins/platforms/xcb/qxcbmime.cpp

@@ -305,7 +305,7 @@ xcb_atom_t QXcbMime::mimeAtomForFormat(QXcbConnection *connection, const QString
         QString formatWithCharset = format;
         formatWithCharset.append(QLatin1String(";charset=utf-8"));
 
-        xcb_atom_t a = connection->internAtom(formatWithCharset.toLatin1());
+        xcb_atom_t a = connection->internAtom(std::move(formatWithCharset).toLatin1());
         if (a && atoms.contains(a)) {
             *requestedEncoding = "utf-8";
             return a;

src/plugins/platforms/xcb/qxcbwindow.cpp

@@ -1512,8 +1512,8 @@ void QXcbWindow::setParent(const QPlatformWindow *parent)
 
 void QXcbWindow::setWindowTitle(const QString &title)
 {
-    const QString fullTitle = formatWindowTitle(title, QString::fromUtf8(" \xe2\x80\x94 ")); // unicode character U+2014, EM DASH
-    const QByteArray ba = fullTitle.toUtf8();
+    QString fullTitle = formatWindowTitle(title, QString::fromUtf8(" \xe2\x80\x94 ")); // unicode character U+2014, EM DASH
+    const QByteArray ba = std::move(fullTitle).toUtf8();
     Q_XCB_CALL(xcb_change_property(xcb_connection(),
                                    XCB_PROP_MODE_REPLACE,
                                    m_window,

src/testlib/qplaintestlogger.cpp

@@ -199,8 +199,8 @@ namespace QTest {
     int formatResult(char * buffer, int bufferSize, T number, int significantDigits)
     {
         QString result = formatResult(number, significantDigits);
-        qstrncpy(buffer, result.toLatin1().constData(), bufferSize);
         int size = result.count();
+        qstrncpy(buffer, std::move(result).toLatin1().constData(), bufferSize);
         return size;
     }
 }

src/tools/qdbusxml2cpp/qdbusxml2cpp.cpp

@@ -217,7 +217,7 @@ static QByteArray qtTypeName(const QString &signature, const QDBusIntrospection:
             annotationName += QString::fromLatin1(".%1%2").arg(QLatin1String(direction)).arg(paramId);
         QString qttype = annotations.value(annotationName);
         if (!qttype.isEmpty())
-            return qttype.toLatin1();
+            return std::move(qttype).toLatin1();
 
         QString oldAnnotationName = QString::fromLatin1("com.trolltech.QtDBus.QtTypeName");
         if (paramId >= 0)
@@ -242,7 +242,7 @@ static QByteArray qtTypeName(const QString &signature, const QDBusIntrospection:
                         "suggest updating to '%s'\n",
                 PROGRAMNAME, qPrintable(oldAnnotationName), qPrintable(inputFile),
                 qPrintable(annotationName));
-        return qttype.toLatin1();
+        return std::move(qttype).toLatin1();
     }
 
     return QVariant::typeToName(QVariant::Type(type));

src/widgets/widgets/qsplitter.cpp

@@ -1800,7 +1800,7 @@ QTextStream& operator>>(QTextStream& ts, QSplitter& splitter)
     line.replace(QLatin1Char(' '), QString());
     line = std::move(line).toUpper();
 
-    splitter.restoreState(line.toLatin1());
+    splitter.restoreState(std::move(line).toLatin1());
     return ts;
 }
 

src/xml/dom/qdom.cpp

@@ -6442,7 +6442,7 @@ void QDomDocumentPrivate::saveDocument(QTextStream& s, const int indent, QDomNod
             if (enc.isEmpty())
                 enc = encoding.cap(5);
             if (!enc.isEmpty())
-                codec = QTextCodec::codecForName(enc.toLatin1().data());
+                codec = QTextCodec::codecForName(std::move(enc).toLatin1());
         }
         if (!codec)
             codec = QTextCodec::codecForName("UTF-8");

src/xml/sax/qxml.cpp

@@ -1407,7 +1407,7 @@ QString QXmlInputSource::fromRawData(const QByteArray &data, bool beginning)
         QString encoding = extractEncodingDecl(d->encodingDeclChars, &needMoreText);
 
         if (!encoding.isEmpty()) {
-            if (QTextCodec *codec = QTextCodec::codecForName(encoding.toLatin1())) {
+            if (QTextCodec *codec = QTextCodec::codecForName(std::move(encoding).toLatin1())) {
                 /* If the encoding is the same, we don't have to do toUnicode() all over again. */
                 if(codec->mibEnum() != mib) {
                     delete d->encMapper;