QStringList: add contains(QLatin1String) overload

... to avoid the expensive conversion from QString to QL1S.

[ChangeLog][QtCore][QStringList] Added contains(QLatin1String) overload.

Change-Id: Ie75839ce9e46e03fe5155a02c7dcf00277b95c8d
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qstringlist.cpp

@@ -299,6 +299,16 @@ QStringList QtPrivate::QStringList_filter(const QStringList *that, const QString
     return res;
 }
 
+template<typename T>
+static bool stringList_contains(const QStringList &stringList, const T &str, Qt::CaseSensitivity cs)
+{
+    for (const auto &string : stringList) {
+        if (string.size() == str.size() && string.compare(str, cs) == 0)
+            return true;
+    }
+    return false;
+}
+
 
 /*!
     \fn bool QStringList::contains(const QString &str, Qt::CaseSensitivity cs) const
@@ -312,12 +322,24 @@ QStringList QtPrivate::QStringList_filter(const QStringList *that, const QString
 bool QtPrivate::QStringList_contains(const QStringList *that, const QString &str,
                                      Qt::CaseSensitivity cs)
 {
-    for (int i = 0; i < that->size(); ++i) {
+    return stringList_contains(*that, str, cs);
-        const QString & string = that->at(i);
+}
-        if (string.length() == str.length() && str.compare(string, cs) == 0)
+
-            return true;
+/*!
-    }
+    \fn bool QStringList::contains(QLatin1String str, Qt::CaseSensitivity cs) const
-    return false;
+    \overload
+    \since 5.10
+
+    Returns \c true if the list contains the string \a str; otherwise
+    returns \c false. The search is case insensitive if \a cs is
+    Qt::CaseInsensitive; the search is case sensitive by default.
+
+    \sa indexOf(), lastIndexOf(), QString::contains()
+ */
+bool QtPrivate::QStringList_contains(const QStringList *that, QLatin1String str,
+                                     Qt::CaseSensitivity cs)
+{
+    return stringList_contains(*that, str, cs);
 }
 
 #ifndef QT_NO_REGEXP

src/corelib/tools/qstringlist.h

@@ -120,6 +120,7 @@ public:
 #endif
 
     inline bool contains(const QString &str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
+    inline bool contains(QLatin1String str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const;
 
     inline QStringList operator+(const QStringList &other) const
     { QStringList n = *this; n += other; return n; }
@@ -165,6 +166,7 @@ namespace QtPrivate {
                                                Qt::CaseSensitivity cs);
 
     bool Q_CORE_EXPORT QStringList_contains(const QStringList *that, const QString &str, Qt::CaseSensitivity cs);
+    bool Q_CORE_EXPORT QStringList_contains(const QStringList *that, QLatin1String str, Qt::CaseSensitivity cs);
     void Q_CORE_EXPORT QStringList_replaceInStrings(QStringList *that, const QString &before, const QString &after,
                                       Qt::CaseSensitivity cs);
 
@@ -222,6 +224,11 @@ inline bool QStringList::contains(const QString &str, Qt::CaseSensitivity cs) co
     return QtPrivate::QStringList_contains(this, str, cs);
 }
 
+inline bool QStringList::contains(QLatin1String str, Qt::CaseSensitivity cs) const
+{
+    return QtPrivate::QStringList_contains(this, str, cs);
+}
+
 inline QStringList &QListSpecialMethods<QString>::replaceInStrings(const QString &before, const QString &after, Qt::CaseSensitivity cs)
 {
     QtPrivate::QStringList_replaceInStrings(self(), before, after, cs);

tests/auto/corelib/tools/qstringlist/tst_qstringlist.cpp

@@ -264,6 +264,15 @@ void tst_QStringList::contains()
     QVERIFY(list.contains("ARTHUR", Qt::CaseInsensitive));
     QVERIFY(list.contains("dent", Qt::CaseInsensitive));
     QVERIFY(!list.contains("hans", Qt::CaseInsensitive));
+
+    QVERIFY(list.contains(QLatin1String("arthur")));
+    QVERIFY(!list.contains(QLatin1String("ArthuR")));
+    QVERIFY(!list.contains(QLatin1String("Hans")));
+    QVERIFY(list.contains(QLatin1String("arthur"), Qt::CaseInsensitive));
+    QVERIFY(list.contains(QLatin1String("ArthuR"), Qt::CaseInsensitive));
+    QVERIFY(list.contains(QLatin1String("ARTHUR"), Qt::CaseInsensitive));
+    QVERIFY(list.contains(QLatin1String("dent"), Qt::CaseInsensitive));
+    QVERIFY(!list.contains(QLatin1String("hans"), Qt::CaseInsensitive));
 }
 
 void tst_QStringList::removeDuplicates_data()