Open Radar

 
Summary: If the right hand side of an IN predicate contains managed objects of different entities collected via -objectWithID: from an array of NSManagedObjectIDs collected via another fetch request and then calling -valueForKeyPath:@"relationship.objectID" on the results , the NSManagedObjectContext will, on calling -executeFetchRequest:error:, return objects that are not in the RHS if they have the same primary key [PK] (last path component of the NSManagedObjectID URI) as a managed object of a different entity which *is* in the RHS.  

Steps to Reproduce:
See the attached sample project that demonstrates this bug.

Expected Results: See log output - there should be no results. More generally, fetch request results with an IN predicate should always be limited to the contents of the RHS of that predicate 

Actual Results: See log output - there are 10*n results (where n is the number of times the program has been run since reseting the simulator). More generally, they are not. 

Regression: Unknown. 

Notes: Ignore CDRSearchOperation. I originally thought the minimum reproduction step required getting the objectIDs from another thread, but it doesn't. 

Relevant code, since Open Radar doesn't accept attachments (I'll upload to Dropbox later):

in -applicationDidFinishLaunching:

    NSMutableArray *array = [[NSMutableArray alloc] initWithCapacity:40];
    for (int i = 0; i < 10; i++)
    {
        Foo *foo = [NSEntityDescription insertNewObjectForEntityForName:@"Foo" inManagedObjectContext:[self managedObjectContext]];
        foo.name = @"Hello";
        Keyword *fooword = [NSEntityDescription insertNewObjectForEntityForName:@"Keyword" inManagedObjectContext:[self managedObjectContext]];
        fooword.keyword = foo.name;
        fooword.foo = foo;
        [array addObject:foo];
        
        Bar *bar = [NSEntityDescription insertNewObjectForEntityForName:@"Bar" inManagedObjectContext:[self managedObjectContext]];
        bar.name = @"goodbye";
        Keyword *barword = [NSEntityDescription insertNewObjectForEntityForName:@"Keyword" inManagedObjectContext:[self managedObjectContext]];
        barword.keyword = bar.name;
        barword.bar = bar;
        [array addObject:bar];
        
        Baz *baz = [NSEntityDescription insertNewObjectForEntityForName:@"Baz" inManagedObjectContext:[self managedObjectContext]];
        baz.name = @"You say";
        Keyword *bazword = [NSEntityDescription insertNewObjectForEntityForName:@"Keyword" inManagedObjectContext:[self managedObjectContext]];
        bazword.keyword = @"You";
        bazword.baz = baz;
        Keyword *bazword2 = [NSEntityDescription insertNewObjectForEntityForName:@"Keyword" inManagedObjectContext:[self managedObjectContext]];
        bazword2.keyword = @"Say";
        bazword2.baz = baz;
        [array addObject:baz];
        
        Qux *qux = [NSEntityDescription insertNewObjectForEntityForName:@"Qux" inManagedObjectContext:[self managedObjectContext]];
        qux.name = @"I say";
        Keyword *quxword = [NSEntityDescription insertNewObjectForEntityForName:@"Keyword" inManagedObjectContext:[self managedObjectContext]];
        quxword.keyword = @"I";
        quxword.qux = qux;
        Keyword *quxword2 = [NSEntityDescription insertNewObjectForEntityForName:@"Keyword" inManagedObjectContext:[self managedObjectContext]];
        quxword2.keyword = @"Say";
        quxword2.qux = qux;
        [array addObject:qux];

    }
    [[self managedObjectContext] save:nil];

    //Uncomment this to see what happens normally
    
//    NSFetchRequest *fooRequest = [[NSFetchRequest alloc] initWithEntityName:@"Foo"];
//    NSFetchRequest *barRequest = [[NSFetchRequest alloc] initWithEntityName:@"Bar"];
//    NSFetchRequest *bazRequest = [[NSFetchRequest alloc] initWithEntityName:@"Baz"];
//    NSFetchRequest *quxRequest = [[NSFetchRequest alloc] initWithEntityName:@"Qux"];
//    NSMutableArray *oids = [[NSMutableArray alloc] init];
//    [oids addObjectsFromArray:[[[self managedObjectContext] executeFetchRequest:fooRequest error:nil] valueForKey:@"objectID"]];
//    [oids addObjectsFromArray:[[[self managedObjectContext] executeFetchRequest:barRequest error:nil] valueForKey:@"objectID"]];
//    [oids addObjectsFromArray:[[[self managedObjectContext] executeFetchRequest:bazRequest error:nil] valueForKey:@"objectID"]];
//    [oids addObjectsFromArray:[[[self managedObjectContext] executeFetchRequest:quxRequest error:nil] valueForKey:@"objectID"]];
//    NSMutableArray *good = [[NSMutableArray alloc] initWithCapacity:[oids count]];
//    for (NSManagedObjectID *oid in oids)
//    {
//        [good addObject:[[self managedObjectContext] objectWithID:oid]];
//    }
//    NSLog(@"the array of NSMOIDs: %@", good);
//    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Foo"];
//    request.predicate = [NSPredicate predicateWithFormat:@"self IN %@", good];
//    NSArray *results = [[self managedObjectContext] executeFetchRequest:request error:nil];
//    NSLog(@"Expected: %@\n\n Actual: %@", [good filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"entity = %@", [NSEntityDescription entityForName:@"Foo" inManagedObjectContext:[self managedObjectContext]]]], results);
    
    
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Keyword"];
    request.predicate = [NSComparisonPredicate predicateWithLeftExpression:[NSExpression expressionForKeyPath:@"keyword"]
                                                           rightExpression:[NSExpression expressionForConstantValue:@"Say"] 
                                                                  modifier:NSDirectPredicateModifier 
                                                                      type:NSContainsPredicateOperatorType
                                                                   options:NSCaseInsensitivePredicateOption];
    NSArray *results = [[self managedObjectContext] executeFetchRequest:request error:nil];
    NSMutableSet *resultSet = [NSMutableSet set];
    [resultSet addObjectsFromArray:[results valueForKeyPath:@"foo.objectID"]];
    [resultSet addObjectsFromArray:[results valueForKeyPath:@"bar.objectID"]];
    [resultSet addObjectsFromArray:[results valueForKeyPath:@"baz.objectID"]];
    [resultSet addObjectsFromArray:[results valueForKeyPath:@"qux.objectID"]];
    [resultSet removeObject:[NSNull null]];
    [self searchOperation:nil didReturnResults:[resultSet allObjects]];
    ...
}


- (void)searchOperation:(id)op didReturnResults:(NSArray *)results
{
    NSFetchRequest *expReq = [[NSFetchRequest alloc] initWithEntityName:@"Foo"];
    expReq.predicate = [NSComparisonPredicate predicateWithLeftExpression:[NSExpression expressionForKeyPath:@"keywords.keyword"] 
                                                          rightExpression:[NSExpression expressionForConstantValue:@"Say"]
                                                                 modifier:NSAnyPredicateModifier 
                                                                     type:NSContainsPredicateOperatorType 
                                                                  options:NSCaseInsensitivePredicateOption];
    NSArray *expLoggit = [[self managedObjectContext] executeFetchRequest:expReq error:nil];
    NSLog(@"Expected Results (should be empty, becuase the only keywords that have \"foo\"s have \"Hello\" as a keyword: %@", expLoggit);

    
    NSMutableArray *array = [[NSMutableArray alloc] initWithCapacity:[results count]];
    for (NSManagedObjectID *oid in results)
    {
        [array addObject:[[self managedObjectContext] objectWithID:oid]];
    }
    NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:@"Foo"];
    request.predicate = [NSPredicate predicateWithFormat:@"self IN %@", array];
    NSArray *loggit = [[self managedObjectContext] executeFetchRequest:request error:nil];
    NSLog(@"Actual Results:%@", loggit);
}