Add a unit test for wxDatePickerCtrl focus events

Unfortunately it doesn't work with wxGTK, as usual, due to
wxUIActionSimulator not working correctly there.

tests/controls/datepickerctrltest.cpp

@@ -16,9 +16,11 @@
 
 #ifndef WX_PRECOMP
     #include "wx/app.h"
+    #include "wx/button.h"
 #endif // WX_PRECOMP
 
 #include "wx/datectrl.h"
+#include "wx/uiaction.h"
 
 #include "testableframe.h"
 #include "testdate.h"
@@ -35,12 +37,15 @@ private:
     CPPUNIT_TEST_SUITE( DatePickerCtrlTestCase );
         CPPUNIT_TEST( Value );
         CPPUNIT_TEST( Range );
+        WXUISIM_TEST( Focus );
     CPPUNIT_TEST_SUITE_END();
 
     void Value();
     void Range();
+    void Focus();
 
     wxDatePickerCtrl* m_datepicker;
+    wxButton* m_button;
 
     wxDECLARE_NO_COPY_CLASS(DatePickerCtrlTestCase);
 };
@@ -54,10 +59,12 @@ CPPUNIT_TEST_SUITE_NAMED_REGISTRATION( DatePickerCtrlTestCase, "DatePickerCtrlTe
 void DatePickerCtrlTestCase::setUp()
 {
     m_datepicker = new wxDatePickerCtrl(wxTheApp->GetTopWindow(), wxID_ANY);
+    m_button = NULL;
 }
 
 void DatePickerCtrlTestCase::tearDown()
 {
+    delete m_button;
     delete m_datepicker;
 }
 
@@ -115,4 +122,45 @@ void DatePickerCtrlTestCase::Range()
     CPPUNIT_ASSERT_EQUAL( dtBeforeEnd, m_datepicker->GetValue() );
 }
 
+#if wxUSE_UIACTIONSIMULATOR
+
+static wxPoint GetRectCenter(const wxRect& r)
+{
+    return (r.GetTopRight() + r.GetBottomLeft()) / 2;
+}
+
+void DatePickerCtrlTestCase::Focus()
+{
+    // Create another control just to give focus to it initially.
+    m_button = new wxButton(wxTheApp->GetTopWindow(), wxID_OK);
+    m_button->Move(0, m_datepicker->GetSize().y * 3);
+    m_button->SetFocus();
+    wxYield();
+
+    CHECK( !m_datepicker->HasFocus() );
+
+    EventCounter setFocus(m_datepicker, wxEVT_SET_FOCUS);
+    EventCounter killFocus(m_datepicker, wxEVT_KILL_FOCUS);
+
+    wxUIActionSimulator sim;
+
+    sim.MouseMove(GetRectCenter(m_datepicker->GetScreenRect()));
+    sim.MouseClick();
+    wxYield();
+
+    REQUIRE( m_datepicker->HasFocus() );
+    CHECK( setFocus.GetCount() == 1 );
+    CHECK( killFocus.GetCount() == 0 );
+
+    sim.MouseMove(GetRectCenter(m_button->GetScreenRect()));
+    sim.MouseClick();
+    wxYield();
+
+    CHECK( !m_datepicker->HasFocus() );
+    CHECK( setFocus.GetCount() == 1 );
+    CHECK( killFocus.GetCount() == 1 );
+}
+
+#endif // wxUSE_UIACTIONSIMULATOR
+
 #endif // wxUSE_DATEPICKCTRL