QStringList::join: add an overload taking a single QChar

This overload avoids the needless heap allocation that the traditional
overload incurs due to the implicit QChar -> QString conversion
involved there.

In order to share the implementation between the two overloads,
QStringList_join now takes the separator as a (Char*,int) tuple
instead of as a QString.

Change-Id: I92961f13a3f19099de2a6e2df9f4789a12fc83a0
Reviewed-by: João Abecasis <joao.abecasis@nokia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 38 insertions, 0 deletions

diff --git a/tests/auto/corelib/tools/qstringlist/tst_qstringlist.cpp b/tests/auto/corelib/tools/qstringlist/tst_qstringlist.cpp
index 16a329f1dd..0f0fa75bc3 100644
--- a/tests/auto/corelib/tools/qstringlist/tst_qstringlist.cpp
+++ b/tests/auto/corelib/tools/qstringlist/tst_qstringlist.cpp
@@ -66,6 +66,8 @@ private slots:
     void join() const;
     void join_data() const;
     void joinEmptiness() const;
+    void joinChar() const;
+    void joinChar_data() const;
 
     void initializeList() const;
 };
@@ -362,6 +364,42 @@ void tst_QStringList::join_data() const
                 << QString("a b c");
 }
 
+void tst_QStringList::joinChar() const
+{
+    QFETCH(QStringList, input);
+    QFETCH(QChar, separator);
+    QFETCH(QString, expectedResult);
+
+    QCOMPARE(input.join(separator), expectedResult);
+}
+
+void tst_QStringList::joinChar_data() const
+{
+    QTest::addColumn<QStringList>("input");
+    QTest::addColumn<QChar>("separator");
+    QTest::addColumn<QString>("expectedResult");
+
+    QTest::newRow("data1")
+                << QStringList()
+                << QChar(QLatin1Char(' '))
+                << QString();
+
+    QTest::newRow("data5")
+                << (QStringList()
+                        << QLatin1String("a")
+                        << QLatin1String("b"))
+                << QChar(QLatin1Char(' '))
+                << QString("a b");
+
+    QTest::newRow("data6")
+                << (QStringList()
+                        << QLatin1String("a")
+                        << QLatin1String("b")
+                        << QLatin1String("c"))
+                << QChar(QLatin1Char(' '))
+                << QString("a b c");
+}
+
 void tst_QStringList::joinEmptiness() const
 {
     QStringList list;