Add wxClearList() function replacing WX_CLEAR_LIST() macro

Keep the macro for compatibility but there is really no reason to use a
macro here.

Also document this macro, even if it's deprecated, as it's used outside
of wxWidgets code too and this allows us to redirect people using it to
wxClearList().

include/wx/list.h

@@ -1292,18 +1292,17 @@ public:
 #endif // wxLIST_COMPATIBILITY
 
 // delete all list elements
-//
-// NB: the class declaration of the list elements must be visible from the
-//     place where you use this macro, otherwise the proper destructor may not
-//     be called (a decent compiler should give a warning about it, but don't
-//     count on it)!
-#define WX_CLEAR_LIST(type, list)                                            \
-    {                                                                        \
-        type::iterator it, en;                                               \
-        for( it = (list).begin(), en = (list).end(); it != en; ++it )        \
-            delete *it;                                                      \
-        (list).clear();                                                      \
-    }
+template <class T>
+inline void wxClearList(T& list)
+{
+    for ( auto& elem: list )
+        delete elem;
+
+    list.clear();
+}
+
+// Deprecated macro, use wxClearList() instead.
+#define WX_CLEAR_LIST(type, list) wxClearList(list)
 
 // append all element of one list to another one
 //

interface/wx/any.h

@@ -86,7 +86,7 @@ public:
                  wxVariant does.
 
                  Note that objects constructed from list-valued variants
-                 require the list to be explicitly cleared using `WX_CLEAR_LIST`
+                 require the list to be explicitly cleared using wxClearList()
                  to avoid leaking memory. This unfortunate behaviour will not
                  be changed to prevent breaking the existing code relying on it.
 
@@ -101,7 +101,7 @@ public:
 
                  // Clear the list to avoid the memory leak.
                  wxAnyList anyList = any.As<wxAnyList>();
-                 WX_CLEAR_LIST(wxAnyList, anyList);
+                 wxClearList(anyList);
                  @endcode
     */
     wxAny(const wxVariant& variant);

interface/wx/list.h

@@ -475,3 +475,19 @@ public:
     defining it.
 */
 #define WX_DEFINE_LIST(T, name)
+
+/**
+    Deprecated macro equivalent to wxClearList().
+
+    @deprecated This macro is deprecated, use wxClearList() instead.
+ */
+#define WX_CLEAR_LIST(type, list) wxClearList(list)
+
+/**
+    Function deletes all elements of the given list, which must be pointers.
+
+    This simple helper function just calls delete on each element of the list.
+
+    @since 3.3.0
+ */
+template <typename T> inline void wxClearList(T& list);

src/common/filesys.cpp

@@ -640,7 +640,7 @@ bool wxFileSystem::HasHandlerForPath(const wxString &location)
 
 void wxFileSystem::CleanUpHandlers()
 {
-    WX_CLEAR_LIST(wxList, m_Handlers);
+    wxClearList(m_Handlers);
 }
 
 // Returns the native path for a file URL

src/common/menucmn.cpp

@@ -143,7 +143,7 @@ wxCONSTRUCTOR_DUMMY( wxMenuBar )
 const wxMenuInfoHelperList& wxMenuBarBase::GetMenuInfos() const
 {
     wxMenuInfoHelperList* list = const_cast< wxMenuInfoHelperList* > (& m_menuInfos);
-    WX_CLEAR_LIST( wxMenuInfoHelperList, *list);
+    wxClearList(*list);
     for (size_t i = 0 ; i < GetMenuCount(); ++i)
     {
         wxMenuInfoHelper* info = new wxMenuInfoHelper();
@@ -382,7 +382,7 @@ void wxMenuBase::Init(long style)
 
 wxMenuBase::~wxMenuBase()
 {
-    WX_CLEAR_LIST(wxMenuItemList, m_items);
+    wxClearList(m_items);
 }
 
 // ----------------------------------------------------------------------------
@@ -901,7 +901,7 @@ wxMenuBarBase::wxMenuBarBase()
 
 wxMenuBarBase::~wxMenuBarBase()
 {
-    WX_CLEAR_LIST(wxMenuList, m_menus);
+    wxClearList(m_menus);
 }
 
 // ----------------------------------------------------------------------------

src/common/nbkbase.cpp

@@ -120,7 +120,7 @@ void wxNotebookBase::AddPageInfo( wxNotebookPageInfo* info )
 const wxNotebookPageInfoList& wxNotebookBase::GetPageInfos() const
 {
     wxNotebookPageInfoList* list = const_cast< wxNotebookPageInfoList* >( &m_pageInfos );
-    WX_CLEAR_LIST( wxNotebookPageInfoList, *list );
+    wxClearList(*list);
     for( size_t i = 0; i < GetPageCount(); ++i )
     {
         wxNotebookPageInfo *info = new wxNotebookPageInfo();

src/common/sizer.cpp

@@ -802,7 +802,7 @@ bool wxSizerItem::IsShown() const
 
 wxSizer::~wxSizer()
 {
-    WX_CLEAR_LIST(wxSizerItemList, m_children);
+    wxClearList(m_children);
 }
 
 wxSizerItem* wxSizer::DoInsert( size_t index, wxSizerItem *item )
@@ -1080,7 +1080,7 @@ void wxSizer::Clear( bool delete_windows )
         DeleteWindows();
 
     // Now empty the list
-    WX_CLEAR_LIST(wxSizerItemList, m_children);
+    wxClearList(m_children);
 }
 
 void wxSizer::DeleteWindows()

src/common/tbarbase.cpp

@@ -529,7 +529,7 @@ bool wxToolBarBase::Realize()
 
 wxToolBarBase::~wxToolBarBase()
 {
-    WX_CLEAR_LIST(wxToolBarToolsList, m_tools);
+    wxClearList(m_tools);
 
     // notify the frame that it doesn't have a tool bar any longer to avoid
     // dangling pointers

src/html/htmlwin.cpp

@@ -293,7 +293,7 @@ wxCursor *wxHtmlWindow::ms_cursorDefault = nullptr;
 void wxHtmlWindow::CleanUpStatics()
 {
     wxDELETE(m_DefaultFilter);
-    WX_CLEAR_LIST(wxList, m_Filters);
+    wxClearList(m_Filters);
     wxDELETE(m_GlobalProcessors);
     wxDELETE(ms_cursorLink);
     wxDELETE(ms_cursorText);

src/msw/dc.cpp

@@ -2869,8 +2869,8 @@ void wxMSWDCImpl::AddToDCCache(wxDCCacheEntry* entry)
 
 void wxMSWDCImpl::ClearCache()
 {
-    WX_CLEAR_LIST(wxList, sm_dcCache);
-    WX_CLEAR_LIST(wxList, sm_bitmapCache);
+    wxClearList(sm_dcCache);
+    wxClearList(sm_bitmapCache);
 }
 
 // Clean up cache at app exit

src/richtext/richtextbuffer.cpp

@@ -11759,7 +11759,7 @@ bool wxRichTextCommand::Undo()
 
 void wxRichTextCommand::ClearActions()
 {
-    WX_CLEAR_LIST(wxList, m_actions);
+    wxClearList(m_actions);
 }
 
 /*!

src/richtext/richtextstyles.cpp

@@ -366,10 +366,10 @@ wxRichTextStyleDefinition* wxRichTextStyleSheet::FindStyle(const wxList& list, c
 /// Delete all styles
 void wxRichTextStyleSheet::DeleteStyles()
 {
-    WX_CLEAR_LIST(wxList, m_characterStyleDefinitions);
-    WX_CLEAR_LIST(wxList, m_paragraphStyleDefinitions);
-    WX_CLEAR_LIST(wxList, m_listStyleDefinitions);
-    WX_CLEAR_LIST(wxList, m_boxStyleDefinitions);
+    wxClearList(m_characterStyleDefinitions);
+    wxClearList(m_paragraphStyleDefinitions);
+    wxClearList(m_listStyleDefinitions);
+    wxClearList(m_boxStyleDefinitions);
 }
 
 /// Insert into list of style sheets

src/x11/textctrl.cpp

@@ -201,7 +201,7 @@ wxTextCtrl::wxTextCtrl( wxWindow *parent,
 
 wxTextCtrl::~wxTextCtrl()
 {
-    WX_CLEAR_LIST(wxList, m_undos);
+    wxClearList(m_undos);
 }
 
 bool wxTextCtrl::Create( wxWindow *parent,
@@ -403,7 +403,7 @@ void wxTextCtrl::Clear()
 
     SetScrollbars( m_charWidth, m_lineHeight, 0, 0, 0, 0 );
     Refresh();
-    WX_CLEAR_LIST(wxList, m_undos);
+    wxClearList(m_undos);
 }
 
 void wxTextCtrl::Replace(long from, long to, const wxString& value)

tests/any/anytest.cpp

@@ -657,7 +657,7 @@ void wxAnyTestCase::wxVariantConversions()
     CPPUNIT_ASSERT(variant[0].GetLong() == 15);
     CPPUNIT_ASSERT(variant[1].GetString() == "abc");
     // Avoid the memory leak.
-    WX_CLEAR_LIST(wxAnyList, anyList);
+    wxClearList(anyList);
 
     any = wxAny(vCustomType);
     CPPUNIT_ASSERT(wxANY_CHECK_TYPE(any, wxVariantData*));

tests/benchmarks/htmlparser/htmlpars.cpp

@@ -89,7 +89,7 @@ wx28HtmlParser::~wx28HtmlParser()
     }
     delete m_HandlersStack;
     m_HandlersHash.Clear();
-    WX_CLEAR_LIST(wxList, m_HandlersList);
+    wxClearList(m_HandlersList);
     delete m_entitiesParser;
 }
 

tests/lists/lists.cpp

@@ -203,7 +203,7 @@ void ListsTestCase::wxListCtorTest()
 #if !wxUSE_STD_CONTAINERS
         list1.DeleteContents(true);
 #else
-        WX_CLEAR_LIST(wxListBazs, list1);
+        wxClearList(list1);
 #endif
     }