QHash/QSet - fix QHash::erase when the hash is shared

Before a call to erase on a shared instance would imply that the
item was removed from the shared data (i.e all instances)

This patch improves the behavior to detach and erase the item
specified by the iterator (i.e same behavior as QVector)

Since QSet uses QHash it improves QSet the same way.

Change-Id: I850b1efcf7bdfc85ceddb23128b048af95f75063
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/tests/auto/corelib/tools/qhash/tst_qhash.cpp b/tests/auto/corelib/tools/qhash/tst_qhash.cpp
index 71428310b8..af1c7aed15 100644
--- a/tests/auto/corelib/tools/qhash/tst_qhash.cpp
+++ b/tests/auto/corelib/tools/qhash/tst_qhash.cpp
@@ -78,6 +78,7 @@ private slots:
 
     void qthash_data();
     void qthash();
+    void eraseValidIteratorOnSharedHash();
 };
 
 struct Foo {
@@ -1352,5 +1353,34 @@ void tst_QHash::qthash()
     QTEST(result, "hash");
 }
 
+void tst_QHash::eraseValidIteratorOnSharedHash()
+{
+    QHash<int, int> a, b;
+    a.insert(10, 10);
+    a.insertMulti(10, 25);
+    a.insertMulti(10, 30);
+    a.insert(20, 20);
+    a.insert(40, 40);
+
+    QHash<int, int>::iterator i = a.begin();
+    while (i.value() != 25)
+        ++i;
+
+    b = a;
+    a.erase(i);
+
+    QCOMPARE(b.size(), 5);
+    QCOMPARE(a.size(), 4);
+
+    for (i = a.begin(); i != a.end(); ++i)
+        QVERIFY(i.value() != 25);
+
+    int itemsWith10 = 0;
+    for (i = b.begin(); i != b.end(); ++i)
+        itemsWith10 += (i.key() == 10);
+
+    QCOMPARE(itemsWith10, 3);
+}
+
 QTEST_APPLESS_MAIN(tst_QHash)
 #include "tst_qhash.moc"