Improve std::tuple handling in tests

Currently when doing comparison with std::tuple the fallback toString
method is called which returns a Q_NULLPTR thus not allowing proper
diagnostic of the values that triggered an error. This patch
adds support for std::tuple to improve the tests output readability.

[ChangeLog][QtTest][QCOMPARE] Now outputs contents of std::tuple on
failure.

Change-Id: I046a55e2ce44c3f7728d51e4745120d38aa5e007
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 65 insertions, 0 deletions

diff --git a/tests/auto/testlib/selftests/tuplediagnostics/tst_tuplediagnostics.cpp b/tests/auto/testlib/selftests/tuplediagnostics/tst_tuplediagnostics.cpp
new file mode 100644
index 0000000000..17da52eaba
--- /dev/null
+++ b/tests/auto/testlib/selftests/tuplediagnostics/tst_tuplediagnostics.cpp
@@ -0,0 +1,65 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 Samuel Gaist <samuel.gaist@edeltech.ch>
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Make sure we get a real Q_ASSERT even in release builds
+#ifdef QT_NO_DEBUG
+# undef QT_NO_DEBUG
+#endif
+
+#include <QtTest/QtTest>
+
+class tst_TupleDiagnostics: public QObject
+{
+    Q_OBJECT
+
+private slots:
+    void testEmptyTuple() const;
+    void testSimpleTuple() const;
+    void testTuple() const;
+};
+
+void tst_TupleDiagnostics::testEmptyTuple() const
+{
+    QCOMPARE(std::tuple<>{}, std::tuple<>{});
+}
+
+void tst_TupleDiagnostics::testSimpleTuple() const
+{
+    QCOMPARE(std::tuple<int>{1}, std::tuple<int>{2});
+}
+
+void tst_TupleDiagnostics::testTuple() const
+{
+    std::tuple<int, char, QString> tuple1{42, 'Y', QStringLiteral("tuple1")};
+    std::tuple<int, char, QString> tuple2{42, 'Y', QStringLiteral("tuple2")};
+    QCOMPARE(tuple1, tuple2);
+}
+
+QTEST_MAIN(tst_TupleDiagnostics)
+
+#include "tst_tuplediagnostics.moc"