Introduce Q_STATIC_ASSERT

Example of message of failed assert (gcc 4.6, file tst_qglobal.cpp:300):
tst_qglobal.cpp:300:92: error: invalid application of ‘sizeof’
to incomplete type ‘QStaticAssertFailure<false>’

Change-Id: Ic1798094f718eaad388d754034115aafbbb6bd5e
Reviewed-by: João Abecasis <joao.abecasis@nokia.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/tests/auto/corelib/global/qglobal/tst_qglobal.cpp b/tests/auto/corelib/global/qglobal/tst_qglobal.cpp
index 85aa03f642..9dc78a14c0 100644
--- a/tests/auto/corelib/global/qglobal/tst_qglobal.cpp
+++ b/tests/auto/corelib/global/qglobal/tst_qglobal.cpp
@@ -52,6 +52,7 @@ private slots:
     void qassert();
     void qtry();
     void checkptr();
+    void qstaticassert();
 };
 
 void tst_QGlobal::qIsNull()
@@ -267,5 +268,72 @@ void tst_QGlobal::checkptr()
     QCOMPARE(q_check_ptr(c), c);
 }
 
+// Check Q_STATIC_ASSERT, It should compile
+// note that, we are not able to test Q_STATIC_ASSERT(false), to do it manually someone has
+// to replace expressions (in the asserts) one by one to false, and check if it breaks build.
+class MyTrue
+{
+public:
+    MyTrue()
+    {
+        Q_STATIC_ASSERT(true);
+        Q_STATIC_ASSERT(!false);
+    }
+    ~MyTrue()
+    {
+        Q_STATIC_ASSERT(true);
+        Q_STATIC_ASSERT(!false);
+    }
+    Q_STATIC_ASSERT(true);
+    Q_STATIC_ASSERT(!false);
+};
+
+struct MyExpresion
+{
+    void foo()
+    {
+        Q_STATIC_ASSERT(sizeof(MyTrue) > 0);
+        Q_STATIC_ASSERT(sizeof(MyTrue) > 0);
+    }
+private:
+    Q_STATIC_ASSERT(sizeof(MyTrue) > 0);
+    Q_STATIC_ASSERT(sizeof(MyTrue) > 0);
+};
+
+struct TypeDef
+{
+    typedef int T;
+    Q_STATIC_ASSERT(sizeof(T));
+};
+
+template<typename T1, typename T2>
+struct Template
+{
+    static const bool True = true;
+    typedef typename T1::T DependentType;
+    Q_STATIC_ASSERT(True);
+    Q_STATIC_ASSERT(!!True);
+    Q_STATIC_ASSERT(sizeof(DependentType));
+    Q_STATIC_ASSERT(!!sizeof(DependentType));
+};
+
+struct MyTemplate
+{
+    Q_STATIC_ASSERT(Template<TypeDef, int>::True);
+    Q_STATIC_ASSERT(!!Template<TypeDef, int>::True);
+};
+
+void tst_QGlobal::qstaticassert()
+{
+    // Force compilation of these classes
+    MyTrue tmp1;
+    MyExpresion tmp2;
+    MyTemplate tmp3;
+    Q_UNUSED(tmp1);
+    Q_UNUSED(tmp2);
+    Q_UNUSED(tmp3);
+    QVERIFY(true); // if the test compiles it has passed.
+}
+
 QTEST_MAIN(tst_QGlobal)
 #include "tst_qglobal.moc"