Move management of RKResponseHasBeenMapped to RKObjectRequestOperation instead of RKManagedObjectRequestOperation. Add unit tests.

Code/Network/RKManagedObjectRequestOperation.m

@@ -369,10 +369,11 @@ static NSURL *RKRelativeURLFromURLAndResponseDescriptors(NSURL *URL, NSArray *re
     [self.responseMapperOperation cancel];
 }
 
+// RKResponseHasBeenMappedCacheUserInfoKey is stored by RKObjectRequestOperation
 - (BOOL)canSkipMapping
 {
     NSCachedURLResponse *cachedResponse = [[NSURLCache sharedURLCache] cachedResponseForRequest:self.HTTPRequestOperation.request];
-    return [[cachedResponse.userInfo objectForKey:@"RKResponseHasBeenMapped"] boolValue];
+    return [[cachedResponse.userInfo objectForKey:RKResponseHasBeenMappedCacheUserInfoKey] boolValue];
 }
 
 - (RKMappingResult *)performMappingOnResponse:(NSError **)error
@@ -635,17 +636,7 @@ static NSURL *RKRelativeURLFromURLAndResponseDescriptors(NSURL *URL, NSArray *re
     if (! success || [self isCancelled]) {
         self.error = error;
         return;
-    }
-    
-    NSCachedURLResponse *cachedResponse = [[NSURLCache sharedURLCache] cachedResponseForRequest:self.HTTPRequestOperation.request];
-    if (cachedResponse) {
-        // We're all done mapping this request. Now we set a flag on the cache entry's userInfo dictionary to indicate that the request
-        // corresponding to the cache entry completed successfully, and we can reliably skip mapping if a subsequent request results
-        // in the use of this cachedResponse.
-        NSMutableDictionary *userInfo = cachedResponse.userInfo ? [cachedResponse.userInfo mutableCopy] : [NSMutableDictionary dictionaryWithObject:@YES forKey:@"RKResponseHasBeenMapped"];
-        NSCachedURLResponse *newCachedResponse = [[NSCachedURLResponse alloc] initWithResponse:cachedResponse.response data:cachedResponse.data userInfo:userInfo storagePolicy:cachedResponse.storagePolicy];
-        [[NSURLCache sharedURLCache] storeCachedResponse:newCachedResponse forRequest:self.HTTPRequestOperation.request];
-    }
+    }        
 
     // Refetch all managed objects nested at key paths within the results dictionary before returning
     if (self.mappingResult) {

Code/Network/RKObjectRequestOperation.h

@@ -22,6 +22,11 @@
 #import "RKMappingResult.h"
 #import "RKMapperOperation.h"
 
+/**
+ The key for a Boolean NSNumber value that indicates if a `NSCachedURLResponse` stored in the `NSURLCache` has been object mapped to completion. This key is stored on the `userInfo` of the cached response, if any, just before an `RKObjectRequestOperation` transitions to the finished state.
+ */
+extern NSString * const RKResponseHasBeenMappedCacheUserInfoKey;
+
 /**
  `RKObjectRequestOperation` is an `NSOperation` subclass that implements object mapping on the response body of an `NSHTTPResponse` loaded via an `RKHTTPRequestOperation`.
  

Code/Network/RKObjectRequestOperation.m

@@ -38,6 +38,7 @@
 
 NSString * const RKObjectRequestOperationDidStartNotification = @"RKObjectRequestOperationDidStartNotification";
 NSString * const RKObjectRequestOperationDidFinishNotification = @"RKObjectRequestOperationDidFinishNotification";
+NSString * const RKResponseHasBeenMappedCacheUserInfoKey = @"RKResponseHasBeenMapped";
 
 static void RKIncrementNetworkActivityIndicator()
 {
@@ -315,8 +316,21 @@ static NSString *RKStringDescribingURLResponseWithData(NSURLResponse *response,
     }
     self.mappingResult = mappingResult;
     [self willFinish];
-    
-    if (self.error) self.mappingResult = nil;
+        
+    if (self.error) {
+        self.mappingResult = nil;
+    } else {
+        NSCachedURLResponse *cachedResponse = [[NSURLCache sharedURLCache] cachedResponseForRequest:self.HTTPRequestOperation.request];
+        if (cachedResponse) {
+            // We're all done mapping this request. Now we set a flag on the cache entry's userInfo dictionary to indicate that the request
+            // corresponding to the cache entry completed successfully, and we can reliably skip mapping if a subsequent request results
+            // in the use of this cachedResponse.
+            NSMutableDictionary *userInfo = cachedResponse.userInfo ? [cachedResponse.userInfo mutableCopy] : [NSMutableDictionary dictionary];
+            [userInfo setObject:@YES forKey:RKResponseHasBeenMappedCacheUserInfoKey];
+            NSCachedURLResponse *newCachedResponse = [[NSCachedURLResponse alloc] initWithResponse:cachedResponse.response data:cachedResponse.data userInfo:userInfo storagePolicy:cachedResponse.storagePolicy];
+            [[NSURLCache sharedURLCache] storeCachedResponse:newCachedResponse forRequest:self.HTTPRequestOperation.request];
+        }
+    }
 }
 
 - (void)main

Tests/Logic/Network/RKManagedObjectRequestOperationTest.m

@@ -148,7 +148,7 @@ NSSet *RKSetByRemovingSubkeypathsFromSet(NSSet *setOfKeyPaths);
 }
 
 // 304 'Not Modified'
-- (void)testThatManagedObjectsAreFetchedWhenHandlingANotModifiedResponse
+- (void)testThatManagedObjectsAreFetchedWhenHandlingAResponseThatCanSkipMapping
 {
     RKFetchRequestBlock fetchRequestBlock = ^(NSURL *URL){
         return [NSFetchRequest fetchRequestWithEntityName:@"Human"];
@@ -156,7 +156,15 @@ NSSet *RKSetByRemovingSubkeypathsFromSet(NSSet *setOfKeyPaths);
     
     RKManagedObjectStore *managedObjectStore = [RKTestFactory managedObjectStore];
     RKHuman *human = [NSEntityDescription insertNewObjectForEntityForName:@"Human" inManagedObjectContext:managedObjectStore.mainQueueManagedObjectContext];
-    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"/204_with_not_modified_status" relativeToURL:[RKTestFactory baseURL]]];
+    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"/204" relativeToURL:[RKTestFactory baseURL]]];
+    
+    // Store a cache entry indicating that the response has been previously mapped
+    NSData *responseData = [@"{}" dataUsingEncoding:NSUTF8StringEncoding];
+    NSHTTPURLResponse *response = [[NSHTTPURLResponse alloc] initWithURL:[request URL] statusCode:200 HTTPVersion:@"1.1" headerFields:nil];
+    NSAssert(response, @"Failed to build cached response");
+    NSCachedURLResponse *cachedResponse = [[NSCachedURLResponse alloc] initWithResponse:response data:responseData userInfo:@{RKResponseHasBeenMappedCacheUserInfoKey: @YES} storagePolicy:NSURLCacheStorageAllowed];
+    [[NSURLCache sharedURLCache] storeCachedResponse:cachedResponse forRequest:request];
+    
     RKEntityMapping *humanMapping = [RKEntityMapping mappingForEntityForName:@"Human" inManagedObjectStore:managedObjectStore];
     [humanMapping addPropertyMapping:[RKAttributeMapping attributeMappingFromKeyPath:@"name" toKeyPath:@"name"]];
     

Tests/Logic/Network/RKObjectRequestOperationTest.m

@@ -112,6 +112,7 @@
     NSArray *validErrorCodes = @[ @(NSURLErrorCannotDecodeContentData), @(NSURLErrorCannotFindHost) ];
     assertThat(validErrorCodes, hasItem(@([requestOperation.error code])));
 }
+
 - (void)testSendingAnObjectRequestOperationToAnBrokenURL
 {
     NSMutableURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"http://invalid••™¡.is"]];
@@ -752,4 +753,38 @@
     expect(user.phone).to.equal(@"867-5309");
 }
 
+#pragma mark -
+
+- (void)testThatCacheEntryIsFlaggedWhenMappingCompletes
+{
+    RKObjectMapping *userMapping = [RKObjectMapping mappingForClass:[RKTestComplexUser class]];
+    [userMapping addAttributeMappingsFromDictionary:@{ @"name": @"email" }];
+    RKResponseDescriptor *responseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:userMapping pathPattern:nil keyPath:@"human" statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];
+    
+    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"/coredata/etag" relativeToURL:[RKTestFactory baseURL]]];
+    RKObjectRequestOperation *requestOperation = [[RKObjectRequestOperation alloc] initWithRequest:request responseDescriptors:@[ responseDescriptor ]];
+    [requestOperation start];
+    expect(requestOperation.error).to.beNil();
+    
+    NSCachedURLResponse *response = [[NSURLCache sharedURLCache] cachedResponseForRequest:request];
+    expect(response).notTo.beNil();
+    expect([response.userInfo valueForKey:RKResponseHasBeenMappedCacheUserInfoKey]).to.beTruthy();
+}
+
+- (void)testThatCacheEntryIsNotFlaggedWhenMappingFails
+{
+    RKObjectMapping *userMapping = [RKObjectMapping mappingForClass:[RKTestComplexUser class]];
+    RKResponseDescriptor *responseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:userMapping pathPattern:@"/mismatch" keyPath:nil statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];
+    
+    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"/coredata/etag" relativeToURL:[RKTestFactory baseURL]]];
+    RKObjectRequestOperation *requestOperation = [[RKObjectRequestOperation alloc] initWithRequest:request responseDescriptors:@[ responseDescriptor ]];
+    [requestOperation start];
+    expect(requestOperation.error).notTo.beNil();
+    expect([requestOperation.error localizedDescription]).to.equal(@"No response descriptors match the response loaded.");
+    
+    NSCachedURLResponse *response = [[NSURLCache sharedURLCache] cachedResponseForRequest:request];
+    expect(response).notTo.beNil();
+    expect([response.userInfo valueForKey:RKResponseHasBeenMappedCacheUserInfoKey]).to.beFalsy();
+}
+
 @end

Tests/Server/server.rb

@@ -287,11 +287,6 @@ class RestKitTestServer < Sinatra::Base
     status 304
   end
   
-  get '/204_with_not_modified_status' do
-    status 204
-    response.headers['Status'] = '304 Not Modified'
-  end
-  
   delete '/humans/1234/whitespace' do
     content_type 'application/json'
     status 200