Make mid() and midRef() properly return empty, non-null objects

If we request a substring starting at the very end of the string,
QString::mid should return an empty string, not a null string.
For instance, QString("abc").mid(3, 0) used to return a null
one, while this patch makes it return an empty one. The
same thing applies to QString::midRef() and QByteArray::mid().

Change-Id: Ie9efd7a0622d429efd0fb682c19856c19e9469af
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/tests/auto/other/collections/tst_collections.cpp b/tests/auto/other/collections/tst_collections.cpp
index 4edb9d2f3a..528d3b1737 100644
--- a/tests/auto/other/collections/tst_collections.cpp
+++ b/tests/auto/other/collections/tst_collections.cpp
@@ -1310,8 +1310,8 @@ void tst_Collections::byteArray()
     QVERIFY(hello.mid(0, hello.size()+1) == hello);
 
     QVERIFY(hello.mid(hello.size()-0) == "");
-
-    QVERIFY(hello.mid(hello.size()-0).isNull()); // weird but valid 3.x semantics
+    QVERIFY(hello.mid(hello.size()-0).isEmpty());
+    QVERIFY(!hello.mid(hello.size()-0).isNull());
     QVERIFY(hello.mid(hello.size()-1) == "o");
     QVERIFY(hello.mid(hello.size()-2) == "lo");
     QVERIFY(hello.mid(hello.size()-200) == "hello");
@@ -2030,8 +2030,8 @@ void tst_Collections::qstring()
     QVERIFY(hello.mid(0, hello.size()+1) == hello);
 
     QVERIFY(hello.mid(hello.size()-0) == "");
-
-    QVERIFY(hello.mid(hello.size()-0).isNull());
+    QVERIFY(hello.mid(hello.size()-0).isEmpty());
+    QVERIFY(!hello.mid(hello.size()-0).isNull());
     QVERIFY(hello.mid(hello.size()-1) == "o");
     QVERIFY(hello.mid(hello.size()-2) == "lo");
     QVERIFY(hello.mid(hello.size()-200) == "hello");