[gparted] Refactor merging rules into new merge_operations() (#755214)

[Curtis Gedak <gedakc src gnome org>]

commit cf5d8d928c7fd8c1e2aad6e70dbb6de8c42f4a93
Author: Mike Fleetwood <mike fleetwood googlemail com>
Date:   Tue Sep 15 15:34:12 2015 +0100

    Refactor merging rules into new merge_operations() (#755214)
    
    Creation of the various operations involved various implicit rules about
    how the different types of operations were merged in different cases.
    This was open coded in each ::activate_*() method.  Abstract this into
    new merge_operations() method and make the merging rules explicitly
    specified.
    
    NOTE:
    The removal of operation type checking in the MERGE_LAST_WITH_ANY cases
    is not a problem because all the Operation*::merge_operations() methods
    ensure the operation types match as part of the merge attempt.
    
    Bug 755214 - Refactor operation merging

 include/Win_GParted.h |   10 +++++-
 src/Win_GParted.cc    |   90 ++++++++++++++++++++++---------------------------
 2 files changed, 49 insertions(+), 51 deletions(-)
---
diff --git a/include/Win_GParted.h b/include/Win_GParted.h
index 08adedc..c3118ed 100644
--- a/include/Win_GParted.h
+++ b/include/Win_GParted.h
@@ -38,7 +38,14 @@
 
 namespace GParted
 {
-       
+
+enum MergeType
+{
+       MERGE_LAST_WITH_PREV = 0,
+       MERGE_LAST_WITH_ANY  = 1,
+       MERGE_ALL_ADJACENT   = 2
+};
+
 class Win_GParted : public Gtk::Window
 {
 public:
@@ -61,6 +68,7 @@ private:
 
        void Add_Operation( Operation * operation, int index = -1 ) ;
        bool merge_two_operations( unsigned int first, unsigned int second );
+       void merge_operations( MergeType mergetype );
        void Refresh_Visual();
        bool valid_display_partition_ptr( const Partition * partition_ptr );
        bool Quit_Check_Operations();
diff --git a/src/Win_GParted.cc b/src/Win_GParted.cc
index 0e0393e..ee2cb0e 100644
--- a/src/Win_GParted.cc
+++ b/src/Win_GParted.cc
@@ -758,6 +758,38 @@ bool Win_GParted::merge_two_operations( unsigned int first, unsigned int second
        return false;
 }
 
+void Win_GParted::merge_operations( MergeType mergetype )
+{
+       unsigned int num_ops = operations.size();
+       if ( num_ops <= 1 )
+               return;  // Nothing to merge.  One or fewer operations.
+
+       switch ( mergetype )
+       {
+               case MERGE_LAST_WITH_PREV:
+                       merge_two_operations( num_ops-2, num_ops-1 );
+                       break;
+
+               case MERGE_LAST_WITH_ANY:
+                       for ( unsigned int i = 0 ; i < num_ops-1 ; i ++ )
+                       {
+                               if ( merge_two_operations( i, num_ops-1 ) )
+                                       break;
+                       }
+                       break;
+
+               case MERGE_ALL_ADJACENT:
+                       // Must check against operations.size() as looping continues after
+                       // merging which might have reduced the number of items in the
+                       // vector.
+                       for ( unsigned int i = 0 ; i < operations.size()-1 ; i ++ )
+                       {
+                               merge_two_operations( i, i+1 );
+                       }
+                       break;
+       }
+}
+
 void Win_GParted::Refresh_Visual()
 {
        // How GParted displays partitions in the GUI and manages the lifetime and
@@ -830,7 +862,7 @@ void Win_GParted::Refresh_Visual()
        //
        //         Win_GParted::activate_label_filesystem()
        //             Win_GParted::Add_Operation( operation )
-       //             Win_GParted::merge_two_operations( ... )
+       //             Win_GParted::merge_operations( ... )
        //             Win_GParted::show_operationslist()
        //                 Win_GParted::Refresh_Visual()
        //
@@ -1746,10 +1778,7 @@ void Win_GParted::activate_resize()
 
                        // Try to merge this resize/move operation with the previous
                        // operation only.
-                       if ( operations .size() >= 2 )
-                       {
-                               merge_two_operations( operations.size() - 2, operations.size() - 1 );
-                       }
+                       merge_operations( MERGE_LAST_WITH_PREV );
                }
        }
 
@@ -2014,10 +2043,7 @@ void Win_GParted::activate_delete()
                // newly adjacent and can now be merged.  (Applies to resize/move and
                // format operations on real, already existing partitions which are only
                // merged when adjacent).
-               for ( int t = 0 ; t < static_cast<int>( operations .size() - 1 ) ; t++ )
-               {
-                       merge_two_operations( t, t+1 );
-               }
+               merge_operations( MERGE_ALL_ADJACENT );
 
                Refresh_Visual(); 
                                
@@ -2149,12 +2175,8 @@ void Win_GParted::activate_format( GParted::FILESYSTEM new_fs )
                operation ->icon = render_icon( Gtk::Stock::CONVERT, Gtk::ICON_SIZE_MENU );
 
                Add_Operation( operation ) ;
-
                // Try to merge this format operation with the previous operation only.
-               if ( operations .size() >= 2 )
-               {
-                       merge_two_operations( operations.size() - 2, operations.size() - 1 );
-               }
+               merge_operations( MERGE_LAST_WITH_PREV );
        }
 
        show_operationslist() ;
@@ -2601,16 +2623,8 @@ void Win_GParted::activate_check()
        operation ->icon = render_icon( Gtk::Stock::EXECUTE, Gtk::ICON_SIZE_MENU );
 
        Add_Operation( operation ) ;
-
        // Try to merge this check operation with all previous operations.
-       for ( unsigned int t = 0 ; t < operations .size() - 1 ; t++ )
-       {
-               if ( operations[ t ] ->type == OPERATION_CHECK )
-               {
-                       if ( merge_two_operations( t, operations.size() - 1 ) )
-                               break;
-               }
-       }
+       merge_operations( MERGE_LAST_WITH_ANY );
 
        show_operationslist() ;
 }
@@ -2637,17 +2651,9 @@ void Win_GParted::activate_label_filesystem()
                operation ->icon = render_icon( Gtk::Stock::EXECUTE, Gtk::ICON_SIZE_MENU );
 
                Add_Operation( operation ) ;
-
                // Try to merge this label file system operation with all previous
                // operations.
-               for ( unsigned int t = 0 ; t < operations .size() - 1 ; t++ )
-               {
-                       if ( operations[t]->type == OPERATION_LABEL_FILESYSTEM )
-                       {
-                               if ( merge_two_operations( t, operations.size() - 1 ) )
-                                       break;
-                       }
-               }
+               merge_operations( MERGE_LAST_WITH_ANY );
 
                show_operationslist() ;
        }
@@ -2676,17 +2682,9 @@ void Win_GParted::activate_name_partition()
                operation->icon = render_icon( Gtk::Stock::EXECUTE, Gtk::ICON_SIZE_MENU );
 
                Add_Operation( operation );
-
                // Try to merge this name partition operation with all previous
                // operations.
-               for ( unsigned int t = 0 ; t < operations.size() - 1 ; t++ )
-               {
-                       if ( operations[t]->type == OPERATION_NAME_PARTITION )
-                       {
-                               if( merge_two_operations( t, operations.size() - 1 ) )
-                                       break;
-                       }
-               }
+               merge_operations( MERGE_LAST_WITH_ANY );
 
                show_operationslist();
        }
@@ -2734,16 +2732,8 @@ void Win_GParted::activate_change_uuid()
        operation ->icon = render_icon( Gtk::Stock::EXECUTE, Gtk::ICON_SIZE_MENU );
 
        Add_Operation( operation ) ;
-
        // Try to merge this change UUID operation with all previous operations.
-       for ( unsigned int t = 0 ; t < operations .size() - 1 ; t++ )
-       {
-               if ( operations[ t ] ->type == OPERATION_CHANGE_UUID )
-               {
-                       if( merge_two_operations( t, operations .size() - 1 ) )
-                               break;
-               }
-       }
+       merge_operations( MERGE_LAST_WITH_ANY );
 
        show_operationslist() ;
 }