Unify XCAsset handling logic

Summary: @​public

This diff unifies the logic for detecting when images refer to XCAsset files into a single function (RCTXCAssetNameForURL) and uses it for both +[RCTConvert UIImage:] and RCTImageLoader.

I've also tightened the definition of XCAssets so that it only applies to images inside .car files, not any image inside the main bundle. This avoids using the +[UIImage imageNamed:] when not strictly necessary, which is desirable since that method is not thread-safe, and has undocumented caching behavior that is difficult to reason about.

Reviewed By: @javache

Differential Revision: D2526400

fb-gh-sync-id: 7199c2a44f1d55ff236d2c38a0a9368739b993d5

Libraries/Image/RCTImage.xcodeproj/project.pbxproj

@@ -13,11 +13,11 @@
 		134B00A21B54232B00EC8DFB /* RCTImageUtils.m in Sources */ = {isa = PBXBuildFile; fileRef = 134B00A11B54232B00EC8DFB /* RCTImageUtils.m */; };
 		13EF7F0B1BC42D4E003F47DD /* RCTShadowVirtualImage.m in Sources */ = {isa = PBXBuildFile; fileRef = 13EF7F081BC42D4E003F47DD /* RCTShadowVirtualImage.m */; settings = {ASSET_TAGS = (); }; };
 		13EF7F0C1BC42D4E003F47DD /* RCTVirtualImageManager.m in Sources */ = {isa = PBXBuildFile; fileRef = 13EF7F0A1BC42D4E003F47DD /* RCTVirtualImageManager.m */; settings = {ASSET_TAGS = (); }; };
+		13EF7F7F1BC825B1003F47DD /* RCTXCAssetImageLoader.m in Sources */ = {isa = PBXBuildFile; fileRef = 13EF7F7E1BC825B1003F47DD /* RCTXCAssetImageLoader.m */; settings = {ASSET_TAGS = (); }; };
 		143879381AAD32A300F088A5 /* RCTImageLoader.m in Sources */ = {isa = PBXBuildFile; fileRef = 143879371AAD32A300F088A5 /* RCTImageLoader.m */; };
 		35123E6B1B59C99D00EBAD80 /* RCTImageStoreManager.m in Sources */ = {isa = PBXBuildFile; fileRef = 35123E6A1B59C99D00EBAD80 /* RCTImageStoreManager.m */; };
 		354631681B69857700AA0B86 /* RCTImageEditingManager.m in Sources */ = {isa = PBXBuildFile; fileRef = 354631671B69857700AA0B86 /* RCTImageEditingManager.m */; };
 		58B5118F1A9E6BD600147676 /* RCTImageDownloader.m in Sources */ = {isa = PBXBuildFile; fileRef = 58B5118A1A9E6BD600147676 /* RCTImageDownloader.m */; };
-		83DDA1571B8DCA5800892A1C /* RCTAssetBundleImageLoader.m in Sources */ = {isa = PBXBuildFile; fileRef = 83DDA1561B8DCA5800892A1C /* RCTAssetBundleImageLoader.m */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXCopyFilesBuildPhase section */
@@ -45,6 +45,8 @@
 		13EF7F081BC42D4E003F47DD /* RCTShadowVirtualImage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RCTShadowVirtualImage.m; sourceTree = "<group>"; };
 		13EF7F091BC42D4E003F47DD /* RCTVirtualImageManager.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = RCTVirtualImageManager.h; sourceTree = "<group>"; };
 		13EF7F0A1BC42D4E003F47DD /* RCTVirtualImageManager.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RCTVirtualImageManager.m; sourceTree = "<group>"; };
+		13EF7F7D1BC825B1003F47DD /* RCTXCAssetImageLoader.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = RCTXCAssetImageLoader.h; sourceTree = "<group>"; };
+		13EF7F7E1BC825B1003F47DD /* RCTXCAssetImageLoader.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RCTXCAssetImageLoader.m; sourceTree = "<group>"; };
 		143879361AAD32A300F088A5 /* RCTImageLoader.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = RCTImageLoader.h; sourceTree = "<group>"; };
 		143879371AAD32A300F088A5 /* RCTImageLoader.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RCTImageLoader.m; sourceTree = "<group>"; };
 		35123E691B59C99D00EBAD80 /* RCTImageStoreManager.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = RCTImageStoreManager.h; sourceTree = "<group>"; };
@@ -54,8 +56,6 @@
 		58B5115D1A9E6B3D00147676 /* libRCTImage.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libRCTImage.a; sourceTree = BUILT_PRODUCTS_DIR; };
 		58B511891A9E6BD600147676 /* RCTImageDownloader.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = RCTImageDownloader.h; sourceTree = "<group>"; };
 		58B5118A1A9E6BD600147676 /* RCTImageDownloader.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RCTImageDownloader.m; sourceTree = "<group>"; };
-		83DDA1551B8DCA5800892A1C /* RCTAssetBundleImageLoader.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = RCTAssetBundleImageLoader.h; sourceTree = "<group>"; };
-		83DDA1561B8DCA5800892A1C /* RCTAssetBundleImageLoader.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = RCTAssetBundleImageLoader.m; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -72,8 +72,8 @@
 		58B511541A9E6B3D00147676 = {
 			isa = PBXGroup;
 			children = (
-				83DDA1551B8DCA5800892A1C /* RCTAssetBundleImageLoader.h */,
+				13EF7F7D1BC825B1003F47DD /* RCTXCAssetImageLoader.h */,
-				83DDA1561B8DCA5800892A1C /* RCTAssetBundleImageLoader.m */,
+				13EF7F7E1BC825B1003F47DD /* RCTXCAssetImageLoader.m */,
 				1304D5B01AA8C50D0002E2BE /* RCTGIFImageDecoder.h */,
 				1304D5B11AA8C50D0002E2BE /* RCTGIFImageDecoder.m */,
 				58B511891A9E6BD600147676 /* RCTImageDownloader.h */,
@@ -173,8 +173,8 @@
 				354631681B69857700AA0B86 /* RCTImageEditingManager.m in Sources */,
 				1304D5AB1AA8C4A30002E2BE /* RCTImageView.m in Sources */,
 				13EF7F0B1BC42D4E003F47DD /* RCTShadowVirtualImage.m in Sources */,
+				13EF7F7F1BC825B1003F47DD /* RCTXCAssetImageLoader.m in Sources */,
 				134B00A21B54232B00EC8DFB /* RCTImageUtils.m in Sources */,
-				83DDA1571B8DCA5800892A1C /* RCTAssetBundleImageLoader.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

Libraries/Image/RCTImageDownloader.m

@@ -36,12 +36,12 @@ RCT_EXPORT_MODULE()
 
 - (BOOL)canLoadImageURL:(NSURL *)requestURL
 {
-  // Have to exclude 'file://' from the main bundle, otherwise this would conflict with RCTAssetBundleImageLoader
+  static NSSet *schemes = nil;
-  return
+  static dispatch_once_t onceToken;
-    [requestURL.scheme compare:@"http" options:NSCaseInsensitiveSearch range:NSMakeRange(0, 4)] == NSOrderedSame ||
+  dispatch_once(&onceToken, ^{
-    ([requestURL.scheme caseInsensitiveCompare:@"file"] == NSOrderedSame &&
+    schemes = [[NSSet alloc] initWithObjects:@"http", @"https", @"file", nil];
-     ![requestURL.path hasPrefix:[NSBundle bundleForClass:[self class]].resourcePath]) ||
+  });
-    [requestURL.scheme caseInsensitiveCompare:@"data"] == NSOrderedSame;
+  return [schemes containsObject:requestURL.scheme.lowercaseString];
 }
 
 /**

Libraries/Image/RCTImageLoader.m

@@ -96,14 +96,16 @@ RCT_EXPORT_MODULE()
                                       progressBlock:(RCTImageLoaderProgressBlock)progressBlock
                                     completionBlock:(RCTImageLoaderCompletionBlock)completionBlock
 {
-  if ([imageTag isEqualToString:@""]) {
+  if (imageTag.length == 0) {
     RCTLogWarn(@"source.uri should not be an empty string <Native>");
-    return nil;
+    return ^{};
   }
+
   NSURL *requestURL = [RCTConvert NSURL:imageTag];
   id<RCTImageURLLoader> loadHandler = [self imageURLLoaderForRequest:requestURL];
   if (!loadHandler) {
     RCTLogError(@"No suitable image URL loader found for %@", imageTag);
+    return ^{};
   }
 
   return [loadHandler loadImageForURL:requestURL size:size scale:scale resizeMode:resizeMode progressHandler:^(int64_t progress, int64_t total) {
@@ -120,7 +122,7 @@ RCT_EXPORT_MODULE()
     }
   } completionHandler:^(NSError *error, UIImage *image) {
     RCTDispatchCallbackOnMainQueue(completionBlock, error, image);
-  }] ?: ^{};
+  }];
 }
 
 - (id<RCTImageDecoder>)imageDecoderForRequest:(NSData *)imageData

Libraries/Image/RCTXCAssetImageLoader.h

@@ -9,6 +9,6 @@
 
 #import "RCTImageLoader.h"
 
-@interface RCTAssetBundleImageLoader : NSObject <RCTImageURLLoader>
+@interface RCTXCAssetImageLoader : NSObject <RCTImageURLLoader>
 
 @end

Libraries/Image/RCTXCAssetImageLoader.m

@@ -7,56 +7,33 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  */
 
-#import "RCTAssetBundleImageLoader.h"
+#import "RCTXCAssetImageLoader.h"
 
 #import "RCTUtils.h"
 
-@implementation RCTAssetBundleImageLoader
+@implementation RCTXCAssetImageLoader
 
 RCT_EXPORT_MODULE()
 
-- (NSString *)imageNameForRequestURL:(NSURL *)requestURL
-{
-  if (!requestURL.fileURL) {
-    return nil;
-  }
-
-  NSString *resourcesPath = [NSBundle bundleForClass:[self class]].resourcePath;
-  NSString *requestPath = requestURL.absoluteURL.path;
-  if (requestPath.length < resourcesPath.length + 1) {
-    return nil;
-  }
-
-  return [requestPath substringFromIndex:resourcesPath.length + 1];
-}
-
 - (BOOL)canLoadImageURL:(NSURL *)requestURL
 {
-  NSString *imageName = [self imageNameForRequestURL:requestURL];
+  return RCTIsXCAssetURL(requestURL);
-  if (!imageName.length) {
+}
-    return NO;
-  }
 
-  NSBundle *bundle = [NSBundle bundleForClass:[self class]];
+- (float)imageLoaderPriority
-  if ([bundle URLForResource:imageName withExtension:nil] ||
+{
-      [bundle URLForResource:imageName withExtension:@"png"]) {
+  return 100; // higher priority than any ordinary file loader
-    return YES;
-  }
-
-  // Assume it's an image in the main asset catalog
-  return imageName.pathComponents.count == 1;
 }
 
  - (RCTImageLoaderCancellationBlock)loadImageForURL:(NSURL *)imageURL size:(CGSize)size scale:(CGFloat)scale resizeMode:(UIViewContentMode)resizeMode progressHandler:(RCTImageLoaderProgressBlock)progressHandler completionHandler:(RCTImageLoaderCompletionBlock)completionHandler
 {
-  NSString *imageName = [self imageNameForRequestURL:imageURL];
-
   __block BOOL cancelled = NO;
   dispatch_async(dispatch_get_main_queue(), ^{
     if (cancelled) {
       return;
     }
 
+    NSString *imageName = RCTBundlePathForURL(imageURL);
     UIImage *image = [UIImage imageNamed:imageName];
     if (image) {
       if (progressHandler) {

Libraries/Network/RCTHTTPRequestHandler.m

@@ -47,7 +47,12 @@ RCT_EXPORT_MODULE()
 
 - (BOOL)canHandleRequest:(NSURLRequest *)request
 {
-  return [@[@"http", @"https", @"file"] containsObject:request.URL.scheme.lowercaseString];
+  static NSSet *schemes = nil;
+  static dispatch_once_t onceToken;
+  dispatch_once(&onceToken, ^{
+    schemes = [[NSSet alloc] initWithObjects:@"http", @"https", @"file", nil];
+  });
+  return [schemes containsObject:request.URL.scheme.lowercaseString];
 }
 
 - (NSURLSessionDataTask *)sendRequest:(NSURLRequest *)request

React/Base/RCTConvert.m

@@ -12,6 +12,7 @@
 #import <objc/message.h>
 
 #import "RCTDefines.h"
+#import "RCTUtils.h"
 
 @implementation RCTConvert
 
@@ -102,7 +103,10 @@ RCT_CUSTOM_CONVERTER(NSData *, NSData, [json dataUsingEncoding:NSUTF8StringEncod
       // Assume it's a resource path
       path = [[NSBundle bundleForClass:[self class]].resourcePath stringByAppendingPathComponent:path];
     }
-    return [NSURL fileURLWithPath:path];
+    if (!(URL = [NSURL fileURLWithPath:path])) {
+      RCTLogConvertError(json, @"a valid URL");
+    }
+    return URL;
   }
   @catch (__unused NSException *e) {
     RCTLogConvertError(json, @"a valid URL");
@@ -417,7 +421,9 @@ RCT_CGSTRUCT_CONVERTER(CGAffineTransform, (@[
   if ([json isKindOfClass:[NSString class]]) {
     path = json;
   } else if ([json isKindOfClass:[NSDictionary class]]) {
-    path = [self NSString:json[@"uri"]];
+    if (!(path = [self NSString:json[@"uri"]])) {
+      return nil;
+    }
     scale = [self CGFloat:json[@"scale"]];
     isPackagerAsset = [self BOOL:json[@"__packager_asset"]];
   } else {
@@ -427,36 +433,21 @@ RCT_CGSTRUCT_CONVERTER(CGAffineTransform, (@[
 
   NSURL *URL = [self NSURL:path];
   NSString *scheme = URL.scheme.lowercaseString;
-  if (URL && [scheme isEqualToString:@"file"]) {
+  if ([scheme isEqualToString:@"file"]) {
-    if ([URL.path hasPrefix:[NSBundle mainBundle].resourcePath]) {
+    if (RCTIsXCAssetURL(URL)) {
-      RCTAssertMainThread();
-
       // Image may reside inside a .car file, in which case we have no choice
       // but to use +[UIImage imageNamed] - but this method isn't thread safe
-      static NSMutableDictionary *XCAssetMap = nil;
+      RCTAssertMainThread();
-      if (!XCAssetMap) {
+      NSString *assetName = RCTBundlePathForURL(URL);
-        XCAssetMap = [NSMutableDictionary new];
+      image = [UIImage imageNamed:assetName];
-      }
+    } else {
-      NSNumber *isAsset = XCAssetMap[path];
-      if (!isAsset || isAsset.boolValue) {
-        image = [UIImage imageNamed:path];
-      }
-      if (!isAsset) {
-        // Avoid calling `+imageNamed` again in future if it's not needed.
-        XCAssetMap[path] = @(image != nil);
-      }
-    }
-
-    if (!image) {
-      NSString *filePath = URL.path;
-
       // Attempt to load from the file system
+      NSString *filePath = URL.path;
       if (filePath.pathExtension.length == 0) {
         filePath = [filePath stringByAppendingPathExtension:@"png"];
       }
       image = [UIImage imageWithContentsOfFile:filePath];
     }
-
   } else if ([scheme isEqualToString:@"data"]) {
     image = [UIImage imageWithData:[NSData dataWithContentsOfURL:URL]];
   } else if ([scheme isEqualToString:@"http"] && isPackagerAsset) {

React/Base/RCTUtils.h

@@ -77,3 +77,10 @@ RCT_EXTERN NSURL *RCTDataURL(NSString *mimeType, NSData *data);
 
 // Gzip functionality - compression level in range 0 - 1 (-1 for default)
 RCT_EXTERN NSData *RCTGzipData(NSData *data, float level);
+
+// Returns the relative path within the main bundle for an absolute URL
+// (or nil, if the URL does not specify a path within the main bundle)
+RCT_EXTERN NSString *RCTBundlePathForURL(NSURL *URL);
+
+// Determines if a given image URL actually refers to an XCAsset
+RCT_EXTERN BOOL RCTIsXCAssetURL(NSURL *imageURL);

React/Base/RCTUtils.m

@@ -458,3 +458,38 @@ NSData *RCTGzipData(NSData *input, float level)
 
   return output;
 }
+
+NSString *RCTBundlePathForURL(NSURL *URL)
+{
+  if (!URL.fileURL) {
+    // Not a file path
+    return nil;
+  }
+  NSString *path = URL.path;
+  NSString *bundlePath = [[NSBundle mainBundle] resourcePath];
+  if (![path hasPrefix:bundlePath]) {
+    // Not a bundle-relative file
+    return nil;
+  }
+  return [path substringFromIndex:bundlePath.length + 1];
+}
+
+BOOL RCTIsXCAssetURL(NSURL *imageURL)
+{
+  NSString *name = RCTBundlePathForURL(imageURL);
+  if (name.pathComponents.count != 1) {
+    // URL is invalid, or is a file path, not an XCAsset identifier
+    return NO;
+  }
+  NSString *extension = [name pathExtension];
+  if (extension.length && ![extension isEqualToString:@"png"]) {
+    // Not a png
+    return NO;
+  }
+  extension = extension.length ? nil : @"png";
+  if ([[NSBundle mainBundle] pathForResource:name ofType:extension]) {
+    // File actually exists in bundle, so is not an XCAsset
+    return NO;
+  }
+  return YES;
+}