Fix wxWrapSizer minimal size calculation.

Add a unit test checking that wxWrapSizer::CalcMin() returns the expected
results.

Closes #12464.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66862 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

tests/sizers/wrapsizer.cpp

@@ -0,0 +1,128 @@
+///////////////////////////////////////////////////////////////////////////////
+// Name:        tests/sizers/wrapsizer.cpp
+// Purpose:     Unit tests for wxWrapSizer
+// Author:      Catalin Raceanu
+// Created:     2010-10-23
+// RCS-ID:      $Id:$
+// Copyright:   (c) 2010 wxWidgets development team
+///////////////////////////////////////////////////////////////////////////////
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+#include "testprec.h"
+
+#ifdef __BORLANDC__
+    #pragma hdrstop
+#endif
+
+#ifndef WX_PRECOMP
+    #include "wx/app.h"
+#endif // WX_PRECOMP
+
+#include "wx/wrapsizer.h"
+
+#include "asserthelper.h"
+
+// ----------------------------------------------------------------------------
+// test class
+// ----------------------------------------------------------------------------
+
+class WrapSizerTestCase : public CppUnit::TestCase
+{
+public:
+    WrapSizerTestCase() { }
+
+    virtual void setUp();
+    virtual void tearDown();
+
+private:
+    CPPUNIT_TEST_SUITE( WrapSizerTestCase );
+        CPPUNIT_TEST( CalcMin );
+    CPPUNIT_TEST_SUITE_END();
+
+    void CalcMin();
+
+    wxWindow *m_win;
+    wxSizer *m_sizer;
+
+    DECLARE_NO_COPY_CLASS(WrapSizerTestCase)
+};
+
+// register in the unnamed registry so that these tests are run by default
+CPPUNIT_TEST_SUITE_REGISTRATION( WrapSizerTestCase );
+
+// also include in it's own registry so that these tests can be run alone
+CPPUNIT_TEST_SUITE_NAMED_REGISTRATION( WrapSizerTestCase, "WrapSizerTestCase" );
+
+// ----------------------------------------------------------------------------
+// test initialization
+// ----------------------------------------------------------------------------
+
+void WrapSizerTestCase::setUp()
+{
+    m_win = new wxWindow(wxTheApp->GetTopWindow(), wxID_ANY);
+    m_win->SetClientSize(180, 240);
+
+    m_sizer = new wxWrapSizer(wxHORIZONTAL);
+    m_win->SetSizer(m_sizer);
+}
+
+void WrapSizerTestCase::tearDown()
+{
+    delete m_win;
+    m_win = NULL;
+
+    m_sizer = NULL;
+}
+
+// ----------------------------------------------------------------------------
+// tests themselves
+// ----------------------------------------------------------------------------
+
+void WrapSizerTestCase::CalcMin()
+{
+    const wxSize sizeTotal = m_win->GetClientSize();
+    wxSize sizeMinExpected;
+
+    // With a single child the min size must be the same as child size.
+    const wxSize sizeChild1 = wxSize(sizeTotal.x/2 - 10, sizeTotal.y/4);
+    sizeMinExpected = sizeChild1;
+
+    wxWindow * const
+        child1 = new wxWindow(m_win, wxID_ANY, wxDefaultPosition, sizeChild1);
+    child1->SetBackgroundColour(*wxRED);
+    m_sizer->Add(child1);
+    m_win->Layout();
+
+    CPPUNIT_ASSERT_EQUAL( sizeMinExpected, m_sizer->CalcMin() );
+
+    // If both children can fit in the same row, the minimal size of the sizer
+    // is determined by the sum of their minimal horizontal dimensions and
+    // the maximum of their minimal vertical dimensions.
+    const wxSize sizeChild2 = wxSize(sizeTotal.x/2 + 10, sizeTotal.y/3);
+    sizeMinExpected.x += sizeChild2.x;
+    sizeMinExpected.y = wxMax(sizeChild1.y, sizeChild2.y);
+
+    wxWindow * const
+        child2 = new wxWindow(m_win, wxID_ANY, wxDefaultPosition, sizeChild2);
+    child2->SetBackgroundColour(*wxYELLOW);
+    m_sizer->Add(child2);
+    m_win->Layout();
+
+    CPPUNIT_ASSERT_EQUAL( sizeMinExpected, m_sizer->CalcMin() );
+
+    // Three children will take at least two rows so the minimal size in
+    // vertical direction must increase.
+    const wxSize sizeChild3 = wxSize(sizeTotal.x/2, sizeTotal.y/5);
+    sizeMinExpected.y += sizeChild3.y;
+
+    wxWindow * const
+        child3 = new wxWindow(m_win, wxID_ANY, wxDefaultPosition, sizeChild3);
+    child3->SetBackgroundColour(*wxGREEN);
+    m_sizer->Add(child3);
+    m_win->Layout();
+
+    CPPUNIT_ASSERT_EQUAL( sizeMinExpected, m_sizer->CalcMin() );
+}