Fix core data migration bug by making sure that the database store is…

… migrated through all versions. Uses ALIterativeMigrator (see https://github.com/noahmiller/IterativeMigration)

OpenEmu/ALIterativeMigrator.h

@@ -0,0 +1,97 @@
+/*
+ Copyright (c) 2013, Art & Logic
+ All rights reserved.
+ 
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+ 
+ 1. Redistributions of source code must retain the above copyright notice, this
+ list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+ 
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ 
+ The views and conclusions contained in the software and documentation are those
+ of the authors and should not be interpreted as representing official policies,
+ either expressed or implied, of the FreeBSD Project.
+*/
+
+#import <Foundation/Foundation.h>
+
+/**
+ * Iteratively migrates a persistent Core Data store along a series of ordered
+ * managed object models.  Allows for easily mixing inferred migrations
+ * with mapping models and custom migrations.
+ */
+@interface ALIterativeMigrator : NSObject
+
+/**
+ * Iteratively migrates the store at the given URL from its current model
+ * to the given finalModel in order through the list of modelNames.
+ *
+ * Does nothing (returns YES) if the persistent store does not yet exist
+ * at the given sourceStoreURL.
+ *
+ * @param sourceStoreURL The file URL to the persistent store file.
+ * @param sourceStoreType The type of store at sourceStoreURL
+ *        (see NSPersistentStoreCoordinator for possible values).
+ * @param finalModel The final target managed object model for the migration manager.
+ *        At the end of the migration, the persistent store should be migrated
+ *        to this model.
+ * @param modelNames *.mom file names for each of the managed object models
+ *        through which the persistent store might need to be migrated.
+ *        The model names should be ordered in such a way that migration
+ *        from one to the next can occur either using a custom mapping model
+ *        or an inferred mapping model.
+ *        The *.mom files should be stored in the top level of the main bundle.
+ * @param error If an error occurs during the migration, upon return contains
+ *        an NSError object that describes the problem.
+ *
+ * @return YES if the migration proceeds without errors, otherwise NO.
+ */
++ (BOOL)iterativeMigrateURL:(NSURL*)sourceStoreURL
+                     ofType:(NSString*)sourceStoreType
+                    toModel:(NSManagedObjectModel*)finalModel
+          orderedModelNames:(NSArray*)modelNames
+                      error:(NSError**)error;
+
+/**
+ * Migrates the store at the given URL from one object model to another
+ * using the given mapping model.  Writes the store to a temporary file
+ * during migration so that if migration fails, the original store is left intact.
+ *
+ * @param sourceStoreURL The file URL to the persistent store file.
+ * @param sourceStoreType The type of store at sourceStoreURL
+ *        (see NSPersistentStoreCoordinator for possible values).
+ * @param sourceModel The source managed object model for the migration manager.
+ * @param targetModel The target managed object model for the migration manager.
+ * @param mappingModel The mapping model to use to effect the migration.
+ * @param error If an error occurs during the migration, upon return contains 
+ *        an NSError object that describes the problem.
+ *
+ * @return YES if the migration proceeds without errors, otherwise NO.
+ */
++ (BOOL)migrateURL:(NSURL*)sourceStoreURL
+            ofType:(NSString*)sourceStoreType
+         fromModel:(NSManagedObjectModel*)sourceModel
+           toModel:(NSManagedObjectModel*)targetModel
+      mappingModel:(NSMappingModel*)mappingModel
+             error:(NSError**)error;
+
+/**
+ * Returns the error domain used in NSErrors created by this class.
+ */
++ (NSString*)errorDomain;
+
+@end