fixed potential ASPINRemoteImageDownloader crash (#1972)

aljc · appleguy · commit 2bf1b56f550c · 2016-07-24T16:01:15.000-07:00
diff --git a/AsyncDisplayKit/Details/ASPINRemoteImageDownloader.m b/AsyncDisplayKit/Details/ASPINRemoteImageDownloader.m
@@ -214,6 +214,10 @@ - (nullable id)downloadImageWithURL:(NSURL *)URL
 
 - (void)cancelImageDownloadForIdentifier:(id)downloadIdentifier
 {
+  if (!downloadIdentifier) {
+    return;
+  }
+  
   ASDisplayNodeAssert([downloadIdentifier isKindOfClass:[NSUUID class]], @"downloadIdentifier must be NSUUID");
   [[self sharedPINRemoteImageManager] cancelTaskWithUUID:downloadIdentifier];
 }

Original file line number	Diff line number	Diff line change
`@@ -214,6 +214,10 @@ - (nullable id)downloadImageWithURL:(NSURL *)URL`
`214`	`214`
`215`	`215`	`- (void)cancelImageDownloadForIdentifier:(id)downloadIdentifier`
`216`	`216`	`{`
	`217`	`+ if (!downloadIdentifier) {`
	`218`	`+ return;`
	`219`	`+ }`
	`220`	`+`
`217`	`221`	`ASDisplayNodeAssert([downloadIdentifier isKindOfClass:[NSUUID class]], @"downloadIdentifier must be NSUUID");`
`218`	`222`	`[[self sharedPINRemoteImageManager] cancelTaskWithUUID:downloadIdentifier];`
`219`	`223`	`}`