2 files changed, 126 insertions, 0 deletions

diff --git a/tests/auto/corelib/text/qbytearray/tst_qbytearray.cpp b/tests/auto/corelib/text/qbytearray/tst_qbytearray.cpp
index 70180bbf3b..8b2a903627 100644
--- a/tests/auto/corelib/text/qbytearray/tst_qbytearray.cpp
+++ b/tests/auto/corelib/text/qbytearray/tst_qbytearray.cpp
@@ -894,6 +894,27 @@ void tst_QByteArray::append()
     QByteArray twoChars("ab");
     tenChars.append(twoChars);
     QCOMPARE(tenChars.capacity(), 10);
+
+    {
+        QByteArray prepended("abcd");
+        prepended.prepend('a');
+        const qsizetype freeAtEnd = prepended.data_ptr()->freeSpaceAtEnd();
+        QVERIFY(prepended.size() + freeAtEnd < prepended.capacity());
+        prepended += QByteArray(freeAtEnd, 'b');
+        prepended.append('c');
+        QCOMPARE(prepended, QByteArray("aabcd") + QByteArray(freeAtEnd, 'b') + QByteArray("c"));
+    }
+
+    {
+        QByteArray prepended2("aaaaaaaaaa");
+        while (prepended2.size())
+            prepended2.remove(0, 1);
+        QVERIFY(prepended2.data_ptr()->freeSpaceAtBegin() > 0);
+        QByteArray array(prepended2.data_ptr()->freeSpaceAtEnd(), 'a');
+        prepended2 += array;
+        prepended2.append('b');
+        QCOMPARE(prepended2, array + QByteArray("b"));
+    }
 }
 
 void tst_QByteArray::appendExtended_data()
@@ -958,6 +979,38 @@ void tst_QByteArray::insert()
     ba = "one";
     QCOMPARE(ba.insert(1, QByteArrayView(ba)), QByteArray("oonene"));
     QCOMPARE(ba.size(), 6);
+
+    {
+        ba = "one";
+        ba.prepend('a');
+        QByteArray b(ba.data_ptr()->freeSpaceAtEnd(), 'b');
+        QCOMPARE(ba.insert(ba.size() + 1, QByteArrayView(b)), QByteArray("aone ") + b);
+    }
+
+    {
+        ba = "onetwothree";
+        while (ba.size() - 1)
+            ba.remove(0, 1);
+        QByteArray b(ba.data_ptr()->freeSpaceAtEnd() + 1, 'b');
+        QCOMPARE(ba.insert(ba.size() + 1, QByteArrayView(b)), QByteArray("e ") + b);
+    }
+
+    {
+        ba = "one";
+        ba.prepend('a');
+        const qsizetype freeAtEnd = ba.data_ptr()->freeSpaceAtEnd();
+        QCOMPARE(ba.insert(ba.size() + 1, freeAtEnd + 1, 'b'),
+                 QByteArray("aone ") + QByteArray(freeAtEnd + 1, 'b'));
+    }
+
+    {
+        ba = "onetwothree";
+        while (ba.size() - 1)
+            ba.remove(0, 1);
+        const qsizetype freeAtEnd = ba.data_ptr()->freeSpaceAtEnd();
+        QCOMPARE(ba.insert(ba.size() + 1, freeAtEnd + 1, 'b'),
+                 QByteArray("e ") + QByteArray(freeAtEnd + 1, 'b'));
+    }
 }
 
 void tst_QByteArray::insertExtended_data()
diff --git a/tests/auto/corelib/text/qstring/tst_qstring.cpp b/tests/auto/corelib/text/qstring/tst_qstring.cpp
index 79c4fa4ab0..c962496980 100644
--- a/tests/auto/corelib/text/qstring/tst_qstring.cpp
+++ b/tests/auto/corelib/text/qstring/tst_qstring.cpp
@@ -2419,6 +2419,36 @@ void tst_QString::insert_special_cases()
     QCOMPARE(a.insert(1, QLatin1String("BCD")), QString("ABCDEF"));
     QCOMPARE(a.insert(3, QLatin1String("-")), QString("ABC-DEF"));
     QCOMPARE(a.insert(a.size() + 1, QLatin1String("XYZ")), QString("ABC-DEF XYZ"));
+
+    {
+        a = "one";
+        a.prepend(u'a');
+        QString b(a.data_ptr()->freeSpaceAtEnd(), u'b');
+        QCOMPARE(a.insert(a.size() + 1, QLatin1String(b.toLatin1())), QString("aone ") + b);
+    }
+
+    {
+        a = "onetwothree";
+        while (a.size() - 1)
+            a.remove(0, 1);
+        QString b(a.data_ptr()->freeSpaceAtEnd() + 1, u'b');
+        QCOMPARE(a.insert(a.size() + 1, QLatin1String(b.toLatin1())), QString("e ") + b);
+    }
+
+    {
+        a = "one";
+        a.prepend(u'a');
+        QString b(a.data_ptr()->freeSpaceAtEnd(), u'b');
+        QCOMPARE(a.insert(a.size() + 1, b), QString("aone ") + b);
+    }
+
+    {
+        a = "onetwothree";
+        while (a.size() - 1)
+            a.remove(0, 1);
+        QString b(a.data_ptr()->freeSpaceAtEnd() + 1, u'b');
+        QCOMPARE(a.insert(a.size() + 1, b), QString("e ") + b);
+    }
 }
 
 void tst_QString::append_data(bool emptyIsNoop)
@@ -2478,6 +2508,49 @@ void tst_QString::append_special_cases()
         a.append(QLatin1String("BC"));
         QCOMPARE(a, QLatin1String("ABC"));
     }
+
+    {
+        QString a = "one";
+        a.prepend(u'a');
+        QString b(a.data_ptr()->freeSpaceAtEnd(), u'b');
+        QCOMPARE(a.append(QLatin1String(b.toLatin1())), QString("aone") + b);
+    }
+
+    {
+        QString a = "onetwothree";
+        while (a.size() - 1)
+            a.remove(0, 1);
+        QString b(a.data_ptr()->freeSpaceAtEnd(), u'b');
+        QCOMPARE(a.append(QLatin1String(b.toLatin1())), QString("e") + b);
+    }
+
+    {
+        QString a = "one";
+        a.prepend(u'a');
+        QString b(a.data_ptr()->freeSpaceAtEnd(), u'b');
+        QCOMPARE(a.append(b), QString("aone") + b);
+    }
+
+    {
+        QString a = "onetwothree";
+        while (a.size() - 1)
+            a.remove(0, 1);
+        QString b(a.data_ptr()->freeSpaceAtEnd() + 1, u'b');
+        QCOMPARE(a.append(b), QString("e") + b);
+    }
+
+    {
+        QString a = "one";
+        a.prepend(u'a');
+        QCOMPARE(a.append(u'b'), QString("aoneb"));
+    }
+
+    {
+        QString a = "onetwothree";
+        while (a.size() - 1)
+            a.remove(0, 1);
+        QCOMPARE(a.append(u'b'), QString("eb"));
+    }
 }
 
 void tst_QString::append_bytearray_special_cases_data()