Improve handling of failures for localId resolutiosn

Author: flovilmart

Parse/Parse/Internal/Commands/PFRESTCommand.m

@@ -232,10 +232,23 @@ - (BOOL)forEachLocalId:(BOOL(^)(PFObject *pointer))block error:(NSError **)error
     return YES;
 }
 
-- (BOOL)resolveLocalIds:(NSError **)error {
-    if(![self forEachLocalId:^(PFObject *pointer) {
-        return [pointer resolveLocalId:nil];
-    } error: error]) {
+- (BOOL)resolveLocalIds:(NSError * __autoreleasing *)error {
+    __block NSError *firstError;
+    __block BOOL pointerResolutionFailed = NO;
+    BOOL paramEncodingFailed = [self forEachLocalId:^(PFObject *pointer) {
+        NSError *localError;
+        BOOL success = [pointer resolveLocalId:&localError];
+        if (!success && !firstError) {
+            firstError = localError;
+            pointerResolutionFailed = YES;
+        }
+        return YES;
+    } error: error];
+    if (paramEncodingFailed && *error) {
+        return NO;
+    }
+    if (pointerResolutionFailed && firstError) {
+        *error = firstError;
         return NO;
     }
     [self maybeChangeServerOperation];

Parse/Tests/Unit/URLSessionCommandRunnerTests.m

@@ -17,6 +17,8 @@
 #import "PFCommandURLRequestConstructor.h"
 #import "PFRESTCommand.h"
 #import "PFTestCase.h"
+#import "PFObject.h"
+#import "PFObjectPrivate.h"
 #import "PFURLSession.h"
 #import "PFURLSessionCommandRunner_Private.h"
 
@@ -257,4 +259,14 @@ - (void)testLocalIdResolution {
     OCMVerifyAll(mockedCommand);
 }
 
+- (void)testLocalIdResolutionFailure {
+    PFObject *object = [PFObject objectWithoutDataWithClassName:@"Yolo" localId:@"localId"];
+    id command = [PFRESTCommand commandWithHTTPPath:@"" httpMethod:@"" parameters:@{@"object": object} sessionToken:nil error:nil];
+    NSError *error;
+    [command resolveLocalIds:&error];
+    XCTAssertNotNil(error);
+    XCTAssertEqualObjects(error.domain, PFParseErrorDomain);
+    XCTAssertEqualObjects(error.localizedDescription, @"Tried to save an object with a pointer to a new, unsaved object.");
+}
+
 @end