Fix bug #14, don't ask for saving changes when read-only commands are used.

+ Added a new attribute for each undo item (undo::Modification).
+ Each item now modifies or does not modify the document (e.g. selection
  actions do not modify the document).
+ Added an asterisk in tabs when the document is modified.

src/app.cpp

@@ -378,11 +378,22 @@ void app_rebuild_documents_tabs()
   // Insert all other sprites
   for (Documents::const_iterator
 	 it = docs.begin(), end = docs.end(); it != end; ++it) {
-    Document* document = *it;
-    tabsbar->setTabText(get_filename(document->getFilename()), document);
+    const Document* document = *it;
+    app_update_document_tab(document);
   }
 }
 
+void app_update_document_tab(const Document* document)
+{
+  std::string str = get_filename(document->getFilename());
+
+  // Add an asterisk if the document is modified.
+  if (document->isModified())
+    str += "*";
+
+  tabsbar->setTabText(str.c_str(), const_cast<Document*>(document));
+}
+
 /**
  * Updates the recent list menu.
  *

src/app.h

@@ -87,6 +87,7 @@ private:
 void app_refresh_screen(const Document* document);
 
 void app_rebuild_documents_tabs();
+void app_update_document_tab(const Document* document);
 bool app_realloc_recent_list();
 
 int app_get_current_image_type();

src/commands/cmd_cel_properties.cpp

@@ -141,6 +141,7 @@ void CelPropertiesCommand::onExecute(Context* context)
 	cel_writer->opacity != new_opacity) {
       if (undo->isEnabled()) {
 	undo->setLabel("Cel Opacity Change");
+	undo->setModification(undo::ModifyDocument);
 	undo->undo_int(cel_writer, &cel_writer->opacity);
       }
 

src/commands/cmd_deselect_mask.cpp

@@ -56,7 +56,7 @@ void DeselectMaskCommand::onExecute(Context* context)
 {
   ActiveDocumentWriter document(context);
   {
-    UndoTransaction undoTransaction(document, "Mask Deselection");
+    UndoTransaction undoTransaction(document, "Mask Deselection", undo::DoesntModifyDocument);
     undoTransaction.deselectMask();
     undoTransaction.commit();
   }

src/commands/cmd_invert_mask.cpp

@@ -81,6 +81,7 @@ void InvertMaskCommand::onExecute(Context* context)
     /* undo */
     if (undo->isEnabled()) {
       undo->setLabel("Mask Invert");
+      undo->setModification(undo::DoesntModifyDocument);
       undo->undo_set_mask(document);
     }
 

src/commands/cmd_load_mask.cpp

@@ -88,6 +88,7 @@ void LoadMaskCommand::onExecute(Context* context)
   // Add the mask change into the undo history.
   if (undo->isEnabled()) {
     undo->setLabel("Mask Load");
+    undo->setModification(undo::DoesntModifyDocument);
     undo->undo_set_mask(document);
   }
 

src/commands/cmd_mask_all.cpp

@@ -62,6 +62,7 @@ void MaskAllCommand::onExecute(Context* context)
   // Undo
   if (undo->isEnabled()) {
     undo->setLabel("Mask All");
+    undo->setModification(undo::DoesntModifyDocument);
     undo->undo_set_mask(document);
   }
 

src/commands/cmd_merge_down_layer.cpp

@@ -84,6 +84,7 @@ void MergeDownLayerCommand::onExecute(Context* context)
 
   if (undo->isEnabled()) {
     undo->setLabel("Merge Down Layer");
+    undo->setModification(undo::ModifyDocument);
     undo->undo_open();
   }
 

src/commands/cmd_palette_editor.cpp

@@ -667,6 +667,7 @@ void PaletteEntryEditor::updateCurrentSpritePalette(const char* operationName)
 	// Add undo information to save the range of pal entries that will be modified.
 	if (undo->isEnabled()) {
 	  undo->setLabel(operationName);
+	  undo->setModification(undo::ModifyDocument);
 	  undo->undo_set_palette_colors(sprite, currentSpritePalette, from, to);
 	}
 

src/commands/cmd_reselect_mask.cpp

@@ -64,6 +64,7 @@ void ReselectMaskCommand::onExecute(Context* context)
   // Undo
   if (undo->isEnabled()) {
     undo->setLabel("Mask Reselection");
+    undo->setModification(undo::DoesntModifyDocument);
     undo->undo_set_mask(document);
   }
 

src/commands/cmd_save_file.cpp

@@ -139,6 +139,10 @@ static void save_document_in_background(Document* document, bool mark_as_saved)
   delete data->progress;
   fop_free(fop);
   delete data;
+
+  // Update the tab for the document. In this moment, the document is
+  // already marked as saved, so the * is not shown in the tab.
+  app_update_document_tab(document);
 }
 
 /*********************************************************************/
@@ -179,9 +183,10 @@ static void save_as_dialog(Document* document, const char* dlg_title, bool mark_
     /* "no": we must back to select other file-name */
   }
 
+  // Change the document file name
   document->setFilename(filename.c_str());
-  app_rebuild_documents_tabs();
 
+  // Save the document
   save_document_in_background(document, mark_as_saved);
 }
 
@@ -305,7 +310,6 @@ void SaveFileCopyAsCommand::onExecute(Context* context)
 
   // Restore the file name.
   document->setFilename(old_filename.c_str());
-  app_rebuild_documents_tabs();
 }
 
 //////////////////////////////////////////////////////////////////////

src/commands/filters/filter_manager_impl.cpp

@@ -208,6 +208,7 @@ void FilterManagerImpl::apply()
     // Undo stuff
     if (undo->isEnabled()) {
       undo->setLabel(m_filter->getName());
+      undo->setModification(undo::ModifyDocument);
       undo->undo_image(m_src, m_x, m_y, m_w, m_h);
     }
 

src/dialogs/maskcol.cpp

@@ -134,6 +134,7 @@ void dialogs_mask_color(Document* document)
     /* undo */
     if (undo->isEnabled()) {
       undo->setLabel("Mask by Color");
+      undo->setModification(undo::DoesntModifyDocument);
       undo->undo_set_mask(document);
     }
 

src/modules/gui.cpp

@@ -456,6 +456,9 @@ void update_screen_for_document(const Document* document)
       // If it's the same palette update only the editors with the sprite.
       update_editors_with_document(document);
     }
+
+    // Update the tabs (maybe the modified status has been changed).
+    app_update_document_tab(document);
   }
 }
 

src/undo/modification.h

@@ -0,0 +1,23 @@
+// ASEPRITE Undo Library
+// Copyright (C) 2001-2011  David Capello
+//
+// This source file is ditributed under a BSD-like license, please
+// read LICENSE.txt for more information.
+
+#ifndef UNDO_MODIFICATION_H_INCLUDED
+#define UNDO_MODIFICATION_H_INCLUDED
+
+namespace undo {
+
+// The modification flag is used to know if an Undoer item
+// modifies the document's "saved state". It means that if the
+// item modifies the document the user should be asked for "save
+// changes" when he closes the document.
+enum Modification {
+  ModifyDocument,      // This item changes the "saved status" of the document.
+  DoesntModifyDocument // This item doesn't modify the document.
+};
+
+} // namespace undo
+
+#endif // UNDO_MODIFICATION_H_INCLUDED

src/undo/undo_history.cpp

@@ -23,6 +23,7 @@ UndoHistory::UndoHistory(ObjectsContainer* objects)
   m_diffSaved = 0;
   m_enabled = true;
   m_label = NULL;
+  m_modification = ModifyDocument;
 
   m_undoers = new UndoersStack(this);
   try {
@@ -86,6 +87,16 @@ void UndoHistory::setLabel(const char* label)
   m_label = label;
 }
 
+Modification UndoHistory::getModification()
+{
+  return m_modification;
+}
+
+void UndoHistory::setModification(Modification mod)
+{
+  m_modification = mod;
+}
+
 const char* UndoHistory::getNextUndoLabel() const
 {
   ASSERT(canUndo());
@@ -120,8 +131,13 @@ void UndoHistory::runUndo(Direction direction)
 
   do {
     const char* itemLabel = NULL;
-    if (!undoers->empty())
-      itemLabel = (*undoers->begin())->getLabel();
+    Modification itemModification = DoesntModifyDocument;
+
+    if (!undoers->empty()) {
+      UndoersStack::Item* item = *undoers->begin();
+      itemLabel = item->getLabel();
+      itemModification = item->getModification();
+    }
 
     Undoer* undoer = undoers->popUndoer(UndoersStack::PopFromHead);
     if (!undoer)
@@ -138,10 +154,12 @@ void UndoHistory::runUndo(Direction direction)
     // Delete the undoer
     undoer->dispose();
 
-    if (direction == UndoDirection)
-      m_diffCount--;
-    else if (direction == RedoDirection)
-      m_diffCount++;
+    if (itemModification == ModifyDocument) {
+      if (direction == UndoDirection)
+	m_diffCount--;
+      else if (direction == RedoDirection)
+	m_diffCount++;
+    }
   } while (level);
 }
 
@@ -176,7 +194,8 @@ void UndoHistory::pushUndoer(Undoer* undoer)
   int undo_size_limit = (int)get_config_int("Options", "UndoSizeLimit", 8)*1024*1024;
 
   // More differences.
-  m_diffCount++;
+  if (m_modification == ModifyDocument)
+    m_diffCount++;
 
   // Reset the "redo" stack.
   clearRedo();

src/undo/undo_history.h

@@ -7,6 +7,7 @@
 #ifndef UNDO_UNDO_HISTORY_H_INCLUDED
 #define UNDO_UNDO_HISTORY_H_INCLUDED
 
+#include "undo/modification.h"
 #include "undo/undoers_collector.h"
 
 #include <vector>
@@ -45,9 +46,16 @@ public:
 
   void clearRedo();
 
+  // Current label for next added Undoers.
   const char* getLabel();
   void setLabel(const char* label);
 
+  // Change the "modify saved status" flag to be assigned for next
+  // added items. When it is activated means that each added Undoer
+  // modifies the "saved status" of the document.
+  Modification getModification();
+  void setModification(Modification mod);
+
   const char* getNextUndoLabel() const;
   const char* getNextRedoLabel() const;
 
@@ -109,6 +117,7 @@ private:
   int m_diffSaved;
   bool m_enabled;		// Is undo enabled?
   const char* m_label;		// Current label to be applied to all next undo operations.
+  Modification m_modification;  // Current label to be applied to all next undo operations.
 };
 
 } // namespace undo

src/undo/undoers_stack.cpp

@@ -50,7 +50,8 @@ void UndoersStack::pushUndoer(Undoer* undoer)
   ASSERT(undoer != NULL);
 
   try {
-    Item* item = new Item(m_undoHistory->getLabel(), undoer);
+    Item* item = new Item(m_undoHistory->getLabel(),
+			  m_undoHistory->getModification(), undoer);
     try {
       m_items.insert(begin(), item);
     }

src/undo/undoers_stack.h

@@ -7,6 +7,7 @@
 #ifndef UNDO_UNDOERS_STACK_H_INCLUDED
 #define UNDO_UNDOERS_STACK_H_INCLUDED
 
+#include "undo/modification.h"
 #include "undo/undoers_collector.h"
 
 #include <vector>
@@ -32,14 +33,18 @@ public:
   class Item
   {
   public:
-    Item(const char* label, Undoer* undoer)
+    Item(const char* label, Modification mod, Undoer* undoer)
       : m_label(label)
+      , m_mod(mod)
       , m_undoer(undoer) { }
+
     const char* getLabel() const { return m_label; }
+    Modification getModification() const { return m_mod; }
     Undoer* getUndoer() const { return m_undoer; }
 
   private:
     const char* m_label;
+    Modification m_mod;
     Undoer* m_undoer;
   };
 

src/undo_transaction.cpp

@@ -34,7 +34,7 @@
 #include "raster/stock.h"
 #include "undo/undo_history.h"
 
-UndoTransaction::UndoTransaction(Document* document, const char* label)
+UndoTransaction::UndoTransaction(Document* document, const char* label, undo::Modification modification)
 {
   ASSERT(label != NULL);
 
@@ -46,6 +46,7 @@ UndoTransaction::UndoTransaction(Document* document, const char* label)
 
   if (isEnabled()) {
     m_undoHistory->setLabel(label);
+    m_undoHistory->setModification(modification);
     m_undoHistory->undo_open();
   }
 }

src/undo_transaction.h

@@ -20,6 +20,7 @@
 #define UNDO_TRANSACTION_H_INCLUDED
 
 #include "raster/dithering_method.h"
+#include "undo/modification.h"
 
 class Cel;
 class Document;
@@ -55,7 +56,7 @@ public:
   // Starts a undoable sequence of operations in a transaction that
   // can be committed or rollbacked.  All the operations will be
   // grouped in the sprite's undo as an atomic operation.
-  UndoTransaction(Document* document, const char* label);
+  UndoTransaction(Document* document, const char* label, undo::Modification mod = undo::ModifyDocument);
   virtual ~UndoTransaction();
 
   inline Sprite* getSprite() const { return m_sprite;  }

src/util/celmove.cpp

@@ -72,6 +72,7 @@ void move_cel(DocumentWriter& document)
 
   if (undo->isEnabled()) {
     undo->setLabel("Move Cel");
+    undo->setModification(undo::ModifyDocument);
     undo->undo_open();
 
     undo->undo_set_layer(sprite);
@@ -161,6 +162,7 @@ void copy_cel(DocumentWriter& document)
 
   if (undo->isEnabled()) {
     undo->setLabel("Move Cel");
+    undo->setModification(undo::ModifyDocument);
     undo->undo_open();
 
     undo->undo_set_layer(sprite);

src/util/misc.cpp

@@ -156,6 +156,7 @@ int interactive_move_layer(int mode, bool use_undo, int (*callback)())
   if (!editor->editor_click_cancel()) {
     if (use_undo && undo->isEnabled()) {
       undo->setLabel("Cel Movement");
+      undo->setModification(undo::ModifyDocument);
       undo->undo_open();
       undo->undo_int(cel, &cel->x);
       undo->undo_int(cel, &cel->y);

src/widgets/editor/editor.cpp

@@ -1900,8 +1900,17 @@ public:
     m_offset.y = -y1;
 
     // Set undo label for any kind of undo used in the whole loop
-    if (m_document->getUndoHistory()->isEnabled())
+    if (m_document->getUndoHistory()->isEnabled()) {
       m_document->getUndoHistory()->setLabel(m_tool->getText().c_str());
+
+      if (getInk()->isSelection() ||
+	  getInk()->isEyedropper() ||
+	  getInk()->isScrollMovement()) {
+	m_document->getUndoHistory()->setModification(undo::DoesntModifyDocument);
+      }
+      else
+	m_document->getUndoHistory()->setModification(undo::ModifyDocument);
+    }
   }
 
   ~ToolLoopImpl()