Merge pull request realm#4580 from realm/do-sync-error-codes

Use sync error domain errors from network client

Realm/ObjectServerTests/RLMObjectServerTests.m

@@ -19,6 +19,7 @@
 #import "RLMSyncTestCase.h"
 #import "RLMSyncSessionRefreshHandle+ObjectServerTests.h"
 #import "RLMSyncUser+ObjectServerTests.h"
+#import "RLMSyncUtil_Private.h"
 
 #define ACCOUNT_NAME() NSStringFromSelector(_cmd)
 #define CUSTOM_REALM_URL(realm_identifier) \
@@ -124,6 +125,34 @@ - (void)testExistingUsernameRegistration {
     [self waitForExpectationsWithTimeout:2.0 handler:nil];
 }
 
+/// Errors reported in RLMSyncManager.errorHandler shouldn't contain sync error domain errors as underlying error
+- (void)testSyncErrorHandlerErrorDomain {
+    RLMSyncUser *user = [self logInUserForCredentials:[RLMObjectServerTests basicCredentialsWithName:ACCOUNT_NAME()
+                                                                                            register:YES]
+                                               server:[RLMObjectServerTests authServerURL]];
+    XCTAssertNotNil(user);
+
+    NSURL *realmURL = [NSURL URLWithString:@"realm://localhost:9080/THE_PATH_USER_DONT_HAVE_ACCESS_TO/test"];
+
+    RLMRealmConfiguration *c = [RLMRealmConfiguration defaultConfiguration];
+    c.syncConfiguration = [[RLMSyncConfiguration alloc] initWithUser:user realmURL:realmURL];
+
+    NSError *error = nil;
+    __attribute__((objc_precise_lifetime)) RLMRealm *realm = [RLMRealm realmWithConfiguration:c error:&error];
+    XCTAssertNil(error);
+    XCTAssertTrue(realm.isEmpty);
+
+    XCTestExpectation *expectation = [self expectationWithDescription:@""];
+    [RLMSyncManager sharedManager].errorHandler = ^(__unused NSError *error,
+                                                    __unused RLMSyncSession *session) {
+        XCTAssertTrue([error.domain isEqualToString:RLMSyncErrorDomain]);
+        XCTAssertFalse([[error.userInfo[kRLMSyncUnderlyingErrorKey] domain] isEqualToString:RLMSyncErrorDomain]);
+        [expectation fulfill];
+    };
+
+    [self waitForExpectationsWithTimeout:2.0 handler:nil];
+}
+
 /// The pre-emptive token refresh subsystem should function, and properly refresh the token.
 - (void)testPreemptiveTokenRefresh {
     // Prepare the test.

Realm/RLMSyncSessionRefreshHandle.mm

@@ -153,9 +153,17 @@ - (BOOL)_handleSuccessfulRequest:(RLMAuthResponseModel *)model strongUser:(RLMSy
 
 /// Handler for network requests that failed before the JSON parsing stage.
 - (BOOL)_handleFailedRequest:(NSError *)error strongUser:(RLMSyncUser *)user {
-    NSError *syncError = [NSError errorWithDomain:RLMSyncErrorDomain
-                                             code:RLMSyncErrorBadResponse
-                                         userInfo:@{kRLMSyncUnderlyingErrorKey: error}];
+    NSError *syncError;
+    if ([error.domain isEqualToString:RLMSyncErrorDomain]) {
+        // Network client may return sync related error
+        syncError = error;
+    } else {
+        // Something else went wrong
+        syncError = [NSError errorWithDomain:RLMSyncErrorDomain
+                                        code:RLMSyncErrorBadResponse
+                                    userInfo:@{kRLMSyncUnderlyingErrorKey: error}];
+    }
+
     if (self.completionBlock) {
         self.completionBlock(syncError);
     }

RealmSwift/Sync.swift

@@ -73,6 +73,14 @@ public typealias UserCompletionBlock = RLMUserCompletionBlock
  */
 public typealias SyncError = RLMSyncError
 
+
+/**
+ An error associated with the authentication to the Realm Object Server.
+
+ - see: `RLMSyncAuthError`
+ */
+public typealias SyncAuthError = RLMSyncAuthError
+
 /**
  An enum which can be used to specify the level of logging.