QStringList: add filter(QLatin1StringMatcher) overload

Drive-by change: remove a redundant #include <qset.h>

[ChangeLog][QtCore][QStringList] Added filter(QLatin1StringMatcher)
overload, which may be faster when searching in large lists or lists
with longer strings.

Change-Id: I1551e98360b5c1f536d935efc46151ef9992152c
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/doc/snippets/qstringlist/main.cpp

@@ -4,6 +4,7 @@
 #include <QtGui>
 #include <iostream>
 using namespace std;
+using namespace Qt::StringLiterals;
 
 class Widget : public QWidget
 {
@@ -100,6 +101,14 @@ Widget::Widget(QWidget *parent)
     QStringList filtered = veryLongList.filter(matcher);
 //! [18]
     }
+
+    {
+//! [19]
+    QStringList veryLargeList;
+    QLatin1StringMatcher matcher("Street"_L1, Qt::CaseInsensitive);
+    QStringList filtered = veryLargeList.filter(matcher);
+//! [19]
+    }
 }
 
 int main(int argc, char *argv[])

src/corelib/text/qstringlist.cpp

@@ -2,11 +2,11 @@
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 #include <qstringlist.h>
-#include <qset.h>
 #if QT_CONFIG(regularexpression)
 #  include <qregularexpression.h>
 #endif
 #include <private/qduplicatetracker_p.h>
+#include <QtCore/qlatin1stringmatcher.h>
 
 #include <algorithm>
 QT_BEGIN_NAMESPACE
@@ -273,9 +273,25 @@ QStringList QtPrivate::QStringList_filter(const QStringList *that, QStringView s
     For example:
     \snippet qstringlist/main.cpp 18
 
-    \sa contains()
+    \sa contains(), filter(const QLatin1StringMatcher &)
 */
 
+/*!
+    \fn QStringList QStringList::filter(const QLatin1StringMatcher &matcher) const
+    \since 6.9
+
+    Returns a list of all the strings matched by \a matcher (i.e. for which
+    \c matcher.indexIn() returns an index >= 0).
+
+    Using QLatin1StringMatcher may be faster when searching in large
+    lists and/or in lists with long strings (the best way to find out is
+    benchmarking).
+
+    For example:
+    \snippet qstringlist/main.cpp 19
+
+    \sa contains(), filter(const QStringMatcher &)
+*/
 QStringList QtPrivate::QStringList_filter(const QStringList &that, const QStringMatcher &matcher)
 {
     QStringList res;
@@ -286,6 +302,16 @@ QStringList QtPrivate::QStringList_filter(const QStringList &that, const QString
     return res;
 }
 
+QStringList QtPrivate::QStringList_filter(const QStringList &that, const QLatin1StringMatcher &matcher)
+{
+    QStringList res;
+    for (const auto &s : that) {
+        if (matcher.indexIn(s) != -1)
+            res.append(s);
+    }
+    return res;
+}
+
 /*!
     \fn QStringList QStringList::filter(QLatin1StringView str, Qt::CaseSensitivity cs) const
     \since 6.7

src/corelib/text/qstringlist.h

@@ -14,6 +14,7 @@
 
 QT_BEGIN_NAMESPACE
 
+class QLatin1StringMatcher;
 class QRegularExpression;
 
 #if !defined(QT_NO_JAVA_STYLE_ITERATORS)
@@ -34,6 +35,8 @@ namespace QtPrivate {
                                                  Qt::CaseSensitivity cs);
     Q_CORE_EXPORT QStringList QStringList_filter(const QStringList &that,
                                                  const QStringMatcher &matcher);
+    Q_CORE_EXPORT QStringList QStringList_filter(const QStringList &that,
+                                                 const QLatin1StringMatcher &matcher);
 
     bool Q_CORE_EXPORT QStringList_contains(const QStringList *that, QStringView str, Qt::CaseSensitivity cs);
     bool Q_CORE_EXPORT QStringList_contains(const QStringList *that, QLatin1StringView str, Qt::CaseSensitivity cs);
@@ -95,6 +98,9 @@ public:
 
     QStringList filter(const QStringMatcher &matcher) const
     { return QtPrivate::QStringList_filter(*self(), matcher); }
+    QStringList filter(const QLatin1StringMatcher &matcher) const
+    { return QtPrivate::QStringList_filter(*self(), matcher); }
+
     QStringList filter(QLatin1StringView needle, Qt::CaseSensitivity cs = Qt::CaseSensitive) const
     { return QtPrivate::QStringList_filter(*self(), needle, cs); }
     inline QStringList filter(QStringView str, Qt::CaseSensitivity cs = Qt::CaseSensitive) const

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

@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
 
 #include <QTest>
+#include <qlatin1stringmatcher.h>
 #include <qlist.h>
 #include <qregularexpression.h>
 #include <qstringlist.h>
@@ -181,6 +182,7 @@ void tst_QStringList::filter()
         QCOMPARE(list.filter("Bill"_L1), expected);
         QCOMPARE(list.filter(QRegularExpression(u"[i]ll"_s)), expected);
         QCOMPARE(list.filter(QStringMatcher(u"Bill")), expected);
+        QCOMPARE(list.filter(QLatin1StringMatcher("Bill"_L1)), expected);
     }
 
     { // CaseInsensitive
@@ -191,6 +193,7 @@ void tst_QStringList::filter()
         QCOMPARE(list.filter(QRegularExpression(u"[i]ll"_s, QRegularExpression::CaseInsensitiveOption)),
                              expected);
         QCOMPARE(list.filter(QStringMatcher(u"Bill", Qt::CaseInsensitive)), expected);
+        QCOMPARE(list.filter(QLatin1StringMatcher("bill"_L1, Qt::CaseInsensitive)), expected);
     }
 }