Add support for deleting Core Data managed objects that fail validati…

…on out of the mapping context. This enables you to silently drop mapping for managed objects that fail validation. fixes RestKit#691 closes RestKit#694

Code/CoreData/RKManagedObjectMappingOperationDataSource.m

@@ -32,6 +32,7 @@
 #import "RKValueTransformers.h"
 #import "RKRelationshipMapping.h"
 #import "RKObjectUtilities.h"
+#import "NSManagedObject+RKAdditions.h"
 
 extern NSString * const RKObjectMappingNestingAttributeKeyName;
 
@@ -243,8 +244,7 @@ - (id)mappingOperation:(RKMappingOperation *)mappingOperation targetObjectForRep
     }
 
     if (managedObject == nil) {
-        managedObject = [[NSManagedObject alloc] initWithEntity:entity
-                           insertIntoManagedObjectContext:self.managedObjectContext];
+        managedObject = [[NSManagedObject alloc] initWithEntity:entity insertIntoManagedObjectContext:self.managedObjectContext];
         [managedObject setValuesForKeysWithDictionary:entityIdentifierAttributes];
 
         if ([self.managedObjectCache respondsToSelector:@selector(didCreateObject:)]) {
@@ -276,6 +276,16 @@ - (BOOL)commitChangesForMappingOperation:(RKMappingOperation *)mappingOperation
     if ([mappingOperation.objectMapping isKindOfClass:[RKEntityMapping class]]) {
         [self emitDeadlockWarningIfNecessary];
 
+        // Validate unsaved objects
+        if ([mappingOperation.destinationObject isKindOfClass:[NSManagedObject class]] && [(NSManagedObject *)mappingOperation.destinationObject isNew]) {
+            NSError *validationError = nil;
+            if (! [(NSManagedObject *)mappingOperation.destinationObject validateForInsert:&validationError]) {
+                RKLogDebug(@"Unsaved NSManagedObject failed `validateForInsert:` - Deleting object from context: %@", validationError);
+                [self.managedObjectContext deleteObject:mappingOperation.destinationObject];
+                return YES;
+            }
+        }
+
         NSArray *connections = [(RKEntityMapping *)mappingOperation.objectMapping connections];
         if ([connections count] > 0 && self.managedObjectCache == nil) {
             NSDictionary *userInfo = @{ NSLocalizedDescriptionKey: @"Cannot map an entity mapping that contains connection mappings with a data source whose managed object cache is nil." };

Code/Network/RKManagedObjectRequestOperation.m

@@ -654,7 +654,10 @@ - (void)willFinish
         return;
     }
     success = [self saveContext:&error];
-    if (! success) self.error = error;
+    if (! success) {
+        self.error = error;
+        return;
+    }
 
     // Refetch all managed objects nested at key paths within the results dictionary before returning
     if (self.mappingResult) {

Tests/Logic/CoreData/RKManagedObjectMappingOperationDataSourceTest.m

@@ -296,6 +296,7 @@ - (void)testThatMappingAnEntityMappingContainingAConnectionMappingWithANilManage
     RKManagedObjectMappingOperationDataSource *dataSource = [[RKManagedObjectMappingOperationDataSource alloc] initWithManagedObjectContext:managedObjectStore.persistentStoreManagedObjectContext
                                                                                                                                       cache:nil];
     id mockOperation = [OCMockObject mockForClass:[RKMappingOperation class]];
+    [[mockOperation stub] destinationObject];
     [[[mockOperation stub] andReturn:mapping] objectMapping];
     NSError *error = nil;
     BOOL success = [dataSource commitChangesForMappingOperation:mockOperation error:&error];

Tests/Logic/Network/RKManagedObjectRequestOperationTest.m

@@ -13,6 +13,22 @@
 #import "RKTestUser.h"
 #import "RKMappingErrors.h"
 
+@interface RKPost : NSManagedObject
+@end
+
+@implementation RKPost
+
+- (BOOL)validateTitle:(id *)ioValue error:(NSError **)outError {
+    // Don't allow blank titles
+    if ((*ioValue == nil) || ([[(NSString*)*ioValue stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] isEqualToString:@""])) {        
+        return NO;
+    }
+
+    return YES;
+}
+
+@end
+
 @interface RKManagedObjectRequestOperation ()
 - (NSSet *)localObjectsFromFetchRequestsMatchingRequestURL:(NSError **)error;
 @end
@@ -447,6 +463,7 @@ - (void)testThatDeletionOfOrphanedObjectsCanBeSuppressedByPredicate
     [tagOnDiferentObject setValue:@"orphaned" forKey:@"name"];
 
     NSManagedObject *otherPost = [NSEntityDescription insertNewObjectForEntityForName:@"Post" inManagedObjectContext:managedObjectStore.persistentStoreManagedObjectContext];
+    [otherPost setValue:@"Title" forKey:@"title"];
     [otherPost setValue:[NSSet setWithObject:tagOnDiferentObject]  forKey:@"tags"];
 
     RKEntityMapping *postMapping = [RKEntityMapping mappingForEntityForName:@"Post" inManagedObjectStore:managedObjectStore];
@@ -738,4 +755,19 @@ - (void)testThatMappingObjectsWithTheSameIdentificationAttributesAcrossTwoObject
     expect(fetchedObjects).to.haveCountOf(1);
 }
 
+- (void)testManagedObjectRequestOperationCompletesAndIgnoresInvalidObjects
+{
+    RKManagedObjectStore *managedObjectStore = [RKTestFactory managedObjectStore];
+    RKEntityMapping *postMapping = [RKEntityMapping mappingForEntityForName:@"Post" inManagedObjectStore:managedObjectStore];
+    [postMapping addAttributeMappingsFromArray:@[ @"title", @"body" ]];
+    RKResponseDescriptor *responseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:postMapping pathPattern:nil keyPath:@"posts" statusCodes:[NSIndexSet indexSetWithIndex:200]];
+
+    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"/posts_with_invalid.json" relativeToURL:[RKTestFactory baseURL]]];
+    RKManagedObjectRequestOperation *managedObjectRequestOperation = [[RKManagedObjectRequestOperation alloc] initWithRequest:request responseDescriptors:@[ responseDescriptor ]];
+    managedObjectRequestOperation.managedObjectContext = managedObjectStore.persistentStoreManagedObjectContext;
+    [managedObjectRequestOperation start];
+    expect(managedObjectRequestOperation.error).to.beNil();
+    expect([managedObjectRequestOperation.mappingResult array]).to.haveCountOf(1);
+}
+
 @end

Tests/Server/server.rb

@@ -302,6 +302,11 @@ def render_fixture(path, options = {})
     content_type 'application/json'
     { :posts => [{:title => 'Post Title', :body => 'Some body.', :tags => [{ :name => 'development' }, { :name => 'restkit' }] }] }.to_json
   end
+
+  get '/posts_with_invalid.json' do
+    content_type 'application/json'
+    { :posts => [{:title => 'Post Title', :body => 'Some body.'}, {:title => '', :body => 'Some body.'} ] }.to_json
+  end
 
   # start the server if ruby file executed directly
   run! if app_file == $0