Encapsulate operation merging inside the Operation* classes (#755214)

Win_GParted::Merge_Operations() method was modifying the internals of
Operation* objects; in particular the partition_new member variable.
This is breaking data hiding and encapsulation tenant of object oriented
programming.

Implement exactly the same operation merge semantics, but hide the
manipulation of the internals of the Operation* objects within the
Operation* classes themselves.

Bug 755214 - Refactor operation merging

include/Operation.h

@@ -45,6 +45,7 @@ public:
 	
 	virtual void apply_to_visual( std::vector<Partition> & partitions ) = 0 ;
 	virtual void create_description() = 0 ;
+	virtual bool merge_operations( const Operation & candidate ) = 0;
 
 	//public variables
 	Device device ;

include/OperationChangeUUID.h

@@ -34,6 +34,7 @@ void apply_to_visual( std::vector<Partition> & partitions ) ;
 
 private:
 	void create_description() ;
+	bool merge_operations( const Operation & candidate );
 } ;
 
 } //GParted

include/OperationCheck.h

@@ -31,6 +31,7 @@ public:
 
 private:
 	void create_description() ;
+	bool merge_operations( const Operation & candidate );
 } ;
 
 } //GParted

include/OperationCopy.h

@@ -36,6 +36,7 @@ public:
 
 private:
 	void create_description() ;
+	bool merge_operations( const Operation & candidate );
 } ;
 
 } //GParted

include/OperationCreate.h

@@ -33,6 +33,7 @@ public:
 
 private:
 	void create_description() ;
+	bool merge_operations( const Operation & candidate );
 } ;
 
 } //GParted

include/OperationDelete.h

@@ -31,6 +31,7 @@ public:
 		
 private:
 	void create_description() ;
+	bool merge_operations( const Operation & candidate );
 	void remove_original_and_adjacent_unallocated( std::vector<Partition> & partitions, int index_orig ) ;
 } ;
 

include/OperationFormat.h

@@ -33,6 +33,7 @@ public:
 
 private:
 	void create_description() ;
+	bool merge_operations( const Operation & candidate );
 } ;
 
 } //GParted

include/OperationLabelFileSystem.h

@@ -33,6 +33,7 @@ public:
 
 private:
 	void create_description() ;
+	bool merge_operations( const Operation & candidate );
 } ;
 
 } //GParted

include/OperationNamePartition.h

@@ -33,6 +33,7 @@ public:
 
 private:
 	void create_description();
+	bool merge_operations( const Operation & candidate );
 };
 
 } //GParted

include/OperationResizeMove.h

@@ -33,7 +33,8 @@ public:
 
 private:
 	void create_description() ;
-	
+	bool merge_operations( const Operation & candidate );
+
 	void apply_normal_to_visual( std::vector<Partition> & partitions ) ;
 	void apply_extended_to_visual( std::vector<Partition> & partitions ) ;
 	

src/OperationChangeUUID.cc

@@ -69,4 +69,23 @@ void OperationChangeUUID::create_description()
 	}
 }
 
+bool OperationChangeUUID::merge_operations( const Operation & candidate )
+{
+	if ( candidate.type == OPERATION_CHANGE_UUID        &&
+	     partition_new  == candidate.partition_original    )
+	{
+		// Changing half the UUID must not override changing all of it
+		if ( candidate.partition_new.uuid != UUID_RANDOM_NTFS_HALF )
+		{
+			partition_new.uuid = candidate.partition_new.uuid;
+			create_description();
+		}
+		// Else no change required to this operation to merge candidate
+
+		return true;
+	}
+
+	return false;
+}
+
 } //GParted

src/OperationCheck.cc

@@ -39,5 +39,14 @@ void OperationCheck::create_description()
 					partition_original .get_path() ) ;
 }
 
-} //GParted
+bool OperationCheck::merge_operations( const Operation & candidate )
+{
+	if ( candidate.type     == OPERATION_CHECK              &&
+	     partition_original == candidate.partition_original    )
+		// No steps required to merge this operation
+		return true;
 
+	return false;
+}
+
+} //GParted

src/OperationCopy.cc

@@ -90,5 +90,9 @@ void OperationCopy::create_description()
 	}
 }
 
-} //GParted
+bool OperationCopy::merge_operations( const Operation & candidate )
+{
+	return false;  // Never merge copy operations
+}
 
+} //GParted

src/OperationCreate.cc

@@ -92,5 +92,9 @@ void OperationCreate::create_description()
 					device .get_path() ) ;
 }
 
-} //GParted
+bool OperationCreate::merge_operations( const Operation & candidate )
+{
+	return false;  // Never merge create operations
+}
 
+} //GParted

src/OperationDelete.cc

@@ -84,7 +84,12 @@ void OperationDelete::create_description()
 					Utils::format_size( partition_original .get_sector_length(), partition_original .sector_size ),
 					partition_original .device_path ) ;
 }
-	
+
+bool OperationDelete::merge_operations( const Operation & candidate )
+{
+	return false;  // Can't merge with an already deleted partition
+}
+
 void OperationDelete::remove_original_and_adjacent_unallocated( std::vector<Partition> & partitions, int index_orig ) 
 {
 	//remove unallocated space following the original partition
@@ -101,4 +106,3 @@ void OperationDelete::remove_original_and_adjacent_unallocated( std::vector<Part
 }
 
 } //GParted
-

src/OperationFormat.cc

@@ -74,5 +74,17 @@ void OperationFormat::create_description()
 					Utils::get_filesystem_string( partition_new .filesystem ) ) ;
 }
 
-} //GParted
+bool OperationFormat::merge_operations( const Operation & candidate )
+{
+	if ( candidate.type == OPERATION_FORMAT             &&
+	     partition_new  == candidate.partition_original    )
+	{
+		partition_new = candidate.partition_new;
+		create_description();
+		return true;
+	}
 
+	return false;
+}
+
+} //GParted

src/OperationLabelFileSystem.cc

@@ -65,4 +65,17 @@ void OperationLabelFileSystem::create_description()
 	}
 }
 
+bool OperationLabelFileSystem::merge_operations( const Operation & candidate )
+{
+	if ( candidate.type == OPERATION_LABEL_FILESYSTEM   &&
+	     partition_new  == candidate.partition_original    )
+	{
+		partition_new.set_filesystem_label( candidate.partition_new.get_filesystem_label() );
+		create_description();
+		return true;
+	}
+
+	return false;
+}
+
 } //GParted

src/OperationNamePartition.cc

@@ -68,4 +68,17 @@ void OperationNamePartition::create_description()
 	}
 }
 
+bool OperationNamePartition::merge_operations( const Operation & candidate )
+{
+	if ( candidate.type == OPERATION_NAME_PARTITION     &&
+	     partition_new  == candidate.partition_original    )
+	{
+		partition_new.name = candidate.partition_new.name;
+		create_description();
+		return true;
+	}
+
+	return false;
+}
+
 } //GParted

src/OperationResizeMove.cc

@@ -208,4 +208,17 @@ void OperationResizeMove::remove_adjacent_unallocated( std::vector<Partition> &
 		partitions .erase( partitions .begin() + ( index_orig -1 ) ) ;
 }
 
+bool OperationResizeMove::merge_operations( const Operation & candidate )
+{
+	if ( candidate.type == OPERATION_RESIZE_MOVE        &&
+	     partition_new  == candidate.partition_original    )
+	{
+		partition_new = candidate.partition_new;
+		create_description();
+		return true;
+	}
+
+	return false;
+}
+
 } //GParted

src/Win_GParted.cc

@@ -746,78 +746,9 @@ bool Win_GParted::Merge_Operations( unsigned int first, unsigned int second )
 	if( first >= operations .size() || second >= operations .size() )
 		return false;
 
-	// Two resize operations of the same partition
-	if ( operations[ first ]->type == OPERATION_RESIZE_MOVE &&
-	     operations[ second ]->type == OPERATION_RESIZE_MOVE &&
-	     operations[ first ]->partition_new == operations[ second ]->partition_original
-	   )
-	{
-		operations[ first ]->partition_new = operations[ second ]->partition_new;
-		operations[ first ]->create_description() ;
-		remove_operation( second );
-
-		return true;
-	}
-	// Two label change operations on the same partition
-	else if ( operations[ first ]->type == OPERATION_LABEL_FILESYSTEM &&
-	          operations[ second ]->type == OPERATION_LABEL_FILESYSTEM &&
-	          operations[ first ]->partition_new == operations[ second ]->partition_original
-	        )
-	{
-		operations[ first ]->partition_new.set_filesystem_label(
-		                        operations[ second ]->partition_new.get_filesystem_label() );
-		operations[ first ]->create_description() ;
-		remove_operation( second );
-
-		return true;
-	}
-	// Two name change operations on the same partition
-	else if ( operations[first]->type == OPERATION_NAME_PARTITION &&
-	          operations[second]->type == OPERATION_NAME_PARTITION &&
-	          operations[first]->partition_new == operations[second]->partition_original
-	        )
-	{
-		operations[first]->partition_new.name = operations[second]->partition_new.name;
-		operations[first]->create_description();
-		remove_operation( second );
-
-		return true;
-	}
-	// Two change-uuid change operations on the same partition
-	else if ( operations[ first ]->type == OPERATION_CHANGE_UUID &&
-	          operations[ second ]->type == OPERATION_CHANGE_UUID &&
-	          operations[ first ]->partition_new == operations[ second ]->partition_original
-	        )
-	{
-		// Changing half the UUID should not override changing all of it
-		if ( operations[ first ]->partition_new.uuid == UUID_RANDOM_NTFS_HALF ||
-		     operations[ second ]->partition_new.uuid == UUID_RANDOM )
-			operations[ first ]->partition_new.uuid = operations[ second ]->partition_new.uuid;
-		operations[ first ]->create_description() ;
-		remove_operation( second );
-
-		return true;
-	}
-	// Two check operations of the same partition
-	else if ( operations[ first ]->type == OPERATION_CHECK &&
-	          operations[ second ]->type == OPERATION_CHECK &&
-	          operations[ first ]->partition_original == operations[ second ]->partition_original
-	        )
+	if ( operations[first]->merge_operations( *operations[second] ) )
 	{
 		remove_operation( second );
-
-		return true;
-	}
-	// Two format operations of the same partition
-	else if ( operations[ first ]->type == OPERATION_FORMAT &&
-	          operations[ second ]->type == OPERATION_FORMAT &&
-	          operations[ first ]->partition_new == operations[ second ]->partition_original
-	        )
-	{
-		operations[ first ]->partition_new = operations[ second ]->partition_new;
-		operations[ first ]->create_description() ;
-		remove_operation( second );
-
 		return true;
 	}