Add support for shared factory object instances

Code/Testing/RKTestFactory.h

@@ -141,6 +141,16 @@ extern NSString * const RKTestFactoryDefaultNamesManagedObjectStore;
 + (id)objectFromFactory:(NSString *)factoryName properties:(NSDictionary *)properties;
 + (id)objectFromFactory:(NSString *)factoryName;
 
+/**
+ Fetches a shared object from the factory with the given name. If an existing object has already been created, then that instance is returned. If a shared instance does not yet exist, one will be constructed and returned for this and all subsequent invocations of `sharedObjectFromFactory:`. Shared object instances are discarded when the factory is torn down.
+
+ Shared objects are used to return object instances for cases where it does not make sense to instantiate a new instance on every invocation of the factory. A common example where this is appropriate is the `managedObjectStore` factory, where construction of a new store on each invocation would yield managed objects that cross Core Data stacks.
+
+ @param factoryName The name of the factory to retrieve the shared instance of.
+ @return The shared object instance for the factory registered with the given name.
+ */
++ (id)sharedObjectFromFactory:(NSString *)factoryName;
+
 /**
  Inserts a new managed object for the `NSEntityDescription` with the given name into the specified  managed object context and sets properties on the instance from the given dictionary. A permanent managed object ID is obtained for the object so that it can be referenced across threads without any further work.
  
@@ -160,30 +170,30 @@ extern NSString * const RKTestFactoryDefaultNamesManagedObjectStore;
  */
 + (NSSet *)factoryNames;
 
-///-------------------------
-/// @name Building Instances
-///-------------------------
+///--------------------------------
+/// @name Retrieving Shared Objects
+///--------------------------------
 
 /**
- Creates and returns an `AFHTTPClient` object using the factory defined for the name `RKTestFactoryDefaultNamesClient`.
+ Fetches the shared `AFHTTPClient` object using the factory defined for the name `RKTestFactoryDefaultNamesClient`.
 
- @return A new client instance.
+ @return The shared client instance.
  */
 + (id)client;
 
 /**
- Creates and returns an `RKObjectManager` object using the factory defined for the name `RKTestFactoryDefaultNamesObjectManager`. 
+ Fetches the shared `RKObjectManager` object using the factory defined for the name `RKTestFactoryDefaultNamesObjectManager`.
 
- @return A new object manager instance.
+ @return The shared object manager instance.
  */
 + (id)objectManager;
 
 /**
- Creates and returns an `RKManagedObjectStore` object using the factory defined for the name `RKTestFactoryDefaultNamesManagedObjectStore`.
+ Fetches the shared an `RKManagedObjectStore` object using the factory defined for the name `RKTestFactoryDefaultNamesManagedObjectStore`.
 
- A new managed object store will be configured and returned. If there is an existing persistent store (i.e. from a previous test invocation), then the persistent store is deleted.
+ On first invocation per factory setup/teardown, a new managed object store will be configured and returned. If there is an existing persistent store (i.e. from a previous test invocation), then the persistent store is deleted.
 
- @return A new managed object store instance.
+ @return The shared managed object store instance.
  */
 + (id)managedObjectStore;
 

Code/Testing/RKTestFactory.m

@@ -17,6 +17,7 @@
 @property (nonatomic, strong) NSURL *baseURL;
 @property (nonatomic, strong) NSString *managedObjectStoreFilename;
 @property (nonatomic, strong) NSMutableDictionary *factoryBlocks;
+@property (nonatomic, strong) NSMutableDictionary *sharedObjectsByFactoryName;
 
 + (RKTestFactory *)sharedFactory;
 - (void)defineFactory:(NSString *)factoryName withBlock:(id (^)())block;
@@ -56,6 +57,7 @@ static RKTestFactory *sharedFactory = nil;
         self.baseURL = [NSURL URLWithString:@"http://127.0.0.1:4567"];
         self.managedObjectStoreFilename = RKTestFactoryDefaultStoreFilename;
         self.factoryBlocks = [NSMutableDictionary new];
+        self.sharedObjectsByFactoryName = [NSMutableDictionary new];
         [self defineDefaultFactories];
     }
 
@@ -77,6 +79,16 @@ static RKTestFactory *sharedFactory = nil;
     return object;
 }
 
+- (id)sharedObjectFromFactory:(NSString *)factoryName
+{
+    id sharedObject = [self.sharedObjectsByFactoryName objectForKey:factoryName];
+    if (! sharedObject) {
+        sharedObject = [self objectFromFactory:factoryName properties:nil];
+        [self.sharedObjectsByFactoryName setObject:sharedObject forKey:factoryName];
+    }
+    return sharedObject;
+}
+
 - (void)defineDefaultFactories
 {
     [self defineFactory:RKTestFactoryDefaultNamesClient withBlock:^id {
@@ -160,6 +172,11 @@ static RKTestFactory *sharedFactory = nil;
     return [[RKTestFactory sharedFactory] objectFromFactory:factoryName properties:nil];
 }
 
++ (id)sharedObjectFromFactory:(NSString *)factoryName
+{
+    return [[RKTestFactory sharedFactory] sharedObjectFromFactory:factoryName];
+}
+
 + (id)insertManagedObjectForEntityForName:(NSString *)entityName
                    inManagedObjectContext:(NSManagedObjectContext *)managedObjectContext
                            withProperties:(NSDictionary *)properties
@@ -187,21 +204,22 @@ static RKTestFactory *sharedFactory = nil;
 
 + (id)client
 {
-    return [self objectFromFactory:RKTestFactoryDefaultNamesClient properties:nil];
+    return [self sharedObjectFromFactory:RKTestFactoryDefaultNamesClient];
 }
 
 + (id)objectManager
 {
-    return [self objectFromFactory:RKTestFactoryDefaultNamesObjectManager properties:nil];
+    return [self sharedObjectFromFactory:RKTestFactoryDefaultNamesObjectManager];
 }
 
 + (id)managedObjectStore
 {
-    return [self objectFromFactory:RKTestFactoryDefaultNamesManagedObjectStore properties:nil];
+    return [self sharedObjectFromFactory:RKTestFactoryDefaultNamesManagedObjectStore];
 }
 
 + (void)setUp
 {
+    [[RKTestFactory sharedFactory].sharedObjectsByFactoryName removeAllObjects];
     [RKObjectManager setSharedManager:nil];
     [RKManagedObjectStore setDefaultStore:nil];
 
@@ -218,6 +236,7 @@ static RKTestFactory *sharedFactory = nil;
 
 + (void)tearDown
 {
+    [[RKTestFactory sharedFactory].sharedObjectsByFactoryName removeAllObjects];
     [RKObjectManager setSharedManager:nil];
     [RKManagedObjectStore setDefaultStore:nil];