QStringRef: add truncate()

Missing part of QString API.

[ChangeLog][QtCore][QStringRef] Added truncate(int).

Change-Id: I49e218daf8f47fcd3dad131155e0abc8e2a133e5
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/tests/auto/corelib/tools/qstringref/tst_qstringref.cpp b/tests/auto/corelib/tools/qstringref/tst_qstringref.cpp
index 7fc855a359..82d103c460 100644
--- a/tests/auto/corelib/tools/qstringref/tst_qstringref.cpp
+++ b/tests/auto/corelib/tools/qstringref/tst_qstringref.cpp
@@ -82,6 +82,7 @@ private slots:
     void integer_conversion_data();
     void integer_conversion();
     void trimmed();
+    void truncate();
     void left();
     void right();
     void mid();
@@ -1839,6 +1840,30 @@ void tst_QStringRef::trimmed()
     QCOMPARE(b.trimmed().compare(QStringLiteral("a")), 0);
 }
 
+void tst_QStringRef::truncate()
+{
+    const QString str = "OriginalString~";
+    const QStringRef cref = str.midRef(0);
+    {
+        QStringRef ref = cref;
+        ref.truncate(1000);
+        QCOMPARE(ref, cref);
+        for (int i = str.size(); i >= 0; --i) {
+            ref.truncate(i);
+            QCOMPARE(ref.size(), i);
+            QCOMPARE(ref, cref.left(i));
+        }
+        QVERIFY(ref.isEmpty());
+    }
+
+    {
+        QStringRef ref = cref;
+        QVERIFY(!ref.isEmpty());
+        ref.truncate(-1);
+        QVERIFY(ref.isEmpty());
+    }
+}
+
 void tst_QStringRef::left()
 {
     QString originalString = "OrginalString~";