Fix crash on trying to getData/save a PFFile without local data.

Author: nlutsenko

Parse/Internal/File/Controller/PFFileController.m

@@ -23,6 +23,7 @@
 #import "PFHash.h"
 #import "PFMacros.h"
 #import "PFRESTFileCommand.h"
+#import "PFErrorUtilities.h"
 
 static NSString *const PFFileControllerCacheDirectoryName_ = @"PFFileCache";
 
@@ -90,6 +91,11 @@ - (BFTask *)downloadFileAsyncWithState:(PFFileState *)fileState
     if (cancellationToken.cancellationRequested) {
         return [BFTask cancelledTask];
     }
+    if (!fileState.secureURLString) {
+        NSError *error = [PFErrorUtilities errorWithCode:kPFErrorUnsavedFile
+                                                 message:@"Can't download a file that doesn't exist on the server or locally."];
+        return [BFTask taskWithError:error];
+    }
 
     @weakify(self);
     return [BFTask taskFromExecutor:[BFExecutor defaultPriorityBackgroundExecutor] withBlock:^id{
@@ -208,13 +214,17 @@ - (BFTask *)uploadFileAsyncWithState:(PFFileState *)fileState
                         sessionToken:(NSString *)sessionToken
                    cancellationToken:(BFCancellationToken *)cancellationToken
                        progressBlock:(PFProgressBlock)progressBlock {
-    PFRESTFileCommand *command = [PFRESTFileCommand uploadCommandForFileWithName:fileState.name
-                                                                    sessionToken:sessionToken];
-
-    @weakify(self);
     if (cancellationToken.cancellationRequested) {
         return [BFTask cancelledTask];
     }
+    if (!sourceFilePath) {
+        NSError *error = [PFErrorUtilities errorWithCode:kPFErrorUnsavedFile
+                                                 message:@"Can't upload a file that doesn't exist locally."];
+        return [BFTask taskWithError:error];
+    }
+
+    PFRESTFileCommand *command = [PFRESTFileCommand uploadCommandForFileWithName:fileState.name sessionToken:sessionToken];
+    @weakify(self);
     return [[[self.dataSource.commandRunner runFileUploadCommandAsync:command
                                                       withContentType:fileState.mimeType
                                                 contentSourceFilePath:sourceFilePath

Parse/PFFile.m

@@ -340,10 +340,9 @@ - (BFTask *)_uploadFileAsyncWithSessionToken:(NSString *)sessionToken
     }
 
     PFFileController *controller = [[self class] fileController];
-    NSString *sourceFilePath = self.stagedFilePath;
     @weakify(self);
     return [[[controller uploadFileAsyncWithState:[self _fileState]
-                                   sourceFilePath:sourceFilePath
+                                   sourceFilePath:self.stagedFilePath
                                      sessionToken:sessionToken
                                 cancellationToken:cancellationToken
                                     progressBlock:progressBlock] continueWithSuccessBlock:^id(BFTask *task) {
@@ -441,11 +440,17 @@ - (NSString *)_cachedFilePath {
 
 - (NSData *)_cachedData {
     NSString *filePath = (self.dirty ? self.stagedFilePath : [self _cachedFilePath]);
+    if (!filePath) {
+        return nil;
+    }
     return [NSData dataWithContentsOfFile:filePath options:NSDataReadingMappedIfSafe error:NULL];
 }
 
 - (NSInputStream *)_cachedDataStream {
     NSString *filePath = (self.dirty ? self.stagedFilePath : [[[self class] fileController] cachedFilePathForFileState:self.state]);
+    if (!filePath) {
+        return nil;
+    }
     return [NSInputStream inputStreamWithFileAtPath:filePath];
 }
 
@@ -504,7 +509,8 @@ - (BOOL)isDirty {
 - (BOOL)isDataAvailable {
     __block BOOL available = NO;
     [self _performDataAccessBlock:^{
-        available = self.dirty || [[NSFileManager defaultManager] fileExistsAtPath:[self _cachedFilePath]];
+        available = ((self.dirty && self.stagedFilePath) ||
+                     (self.url && [[NSFileManager defaultManager] fileExistsAtPath:[self _cachedFilePath]]));
     }];
     return available;
 }