Fix crash when accessing QStyleHints before QGuiApplication is constructed.

Make styleHints a static member variable of QGuiApplicationPrivate and
fix accessor accordingly. Extend tst_QApplication::settableStyleHints()
to run without QApplication instance as well and add a similar test
to  QGuiApplication.

Task-number: QTBUG-44499
Change-Id: I42b92ef38f7dd512d08d70accfa7dd4f09a22f01
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>

2 files changed, 38 insertions, 1 deletions

diff --git a/tests/auto/gui/kernel/qguiapplication/tst_qguiapplication.cpp b/tests/auto/gui/kernel/qguiapplication/tst_qguiapplication.cpp
index 35f441c605..3cf7803cfb 100644
--- a/tests/auto/gui/kernel/qguiapplication/tst_qguiapplication.cpp
+++ b/tests/auto/gui/kernel/qguiapplication/tst_qguiapplication.cpp
@@ -37,7 +37,9 @@
 #include <QtGui/QWindow>
 #include <QtGui/QScreen>
 #include <QtGui/QCursor>
+#include <QtGui/QFont>
 #include <QtGui/QPalette>
+#include <QtGui/QStyleHints>
 #include <qpa/qwindowsysteminterface.h>
 #include <qgenericplugin.h>
 
@@ -74,6 +76,9 @@ private slots:
     void genericPluginsAndWindowSystemEvents();
     void layoutDirection();
     void globalShareContext();
+
+    void settableStyleHints_data();
+    void settableStyleHints(); // Needs to run last as it changes style hints.
 };
 
 void tst_QGuiApplication::cleanup()
@@ -961,4 +966,24 @@ void tst_QGuiApplication::globalShareContext()
 #endif
 }
 
+void tst_QGuiApplication::settableStyleHints_data()
+{
+    QTest::addColumn<bool>("appInstance");
+    QTest::newRow("app") << true;
+    QTest::newRow("no-app") << false;
+}
+
+void tst_QGuiApplication::settableStyleHints()
+{
+    QFETCH(bool, appInstance);
+    int argc = 0;
+    QScopedPointer<QGuiApplication> app;
+    if (appInstance)
+        app.reset(new QGuiApplication(argc, 0));
+
+    const int keyboardInputInterval = 555;
+    QGuiApplication::styleHints()->setKeyboardInputInterval(keyboardInputInterval);
+    QCOMPARE(QGuiApplication::styleHints()->keyboardInputInterval(), keyboardInputInterval);
+}
+
 QTEST_APPLESS_MAIN(tst_QGuiApplication)
diff --git a/tests/auto/widgets/kernel/qapplication/tst_qapplication.cpp b/tests/auto/widgets/kernel/qapplication/tst_qapplication.cpp
index 7e950b33c1..bab3337c0c 100644
--- a/tests/auto/widgets/kernel/qapplication/tst_qapplication.cpp
+++ b/tests/auto/widgets/kernel/qapplication/tst_qapplication.cpp
@@ -172,6 +172,7 @@ private slots:
 
     void abortQuitOnShow();
 
+    void settableStyleHints_data();
     void settableStyleHints();  // Needs to run last as it changes style hints.
 };
 
@@ -2298,10 +2299,21 @@ void tst_QApplication::abortQuitOnShow()
     QCOMPARE(app.exec(), 1);
 }
 
+void tst_QApplication::settableStyleHints_data()
+{
+    QTest::addColumn<bool>("appInstance");
+    QTest::newRow("app") << true;
+    QTest::newRow("no-app") << false;
+}
+
 void tst_QApplication::settableStyleHints()
 {
+    QFETCH(bool, appInstance);
     int argc = 0;
-    QApplication app(argc, 0);
+    QScopedPointer<QApplication> app;
+    if (appInstance)
+        app.reset(new QApplication(argc, 0));
+
     QApplication::setCursorFlashTime(437);
     QCOMPARE(QApplication::cursorFlashTime(), 437);
     QApplication::setDoubleClickInterval(128);