Fabric: Migrate Image to State from LocalData

Summary:
Changelog: [Internal]

We are moving away from LocalData in favour of State.

Reviewed By: shergin

Differential Revision: D19247031

fbshipit-source-id: 8884133b13dd111e8d9e2cd4936bf90bfc5b4932

React/Fabric/Mounting/ComponentViews/Image/RCTImageComponentView.mm

@@ -11,7 +11,6 @@
 #import <React/RCTImageResponseObserverProxy.h>
 #import <react/components/image/ImageComponentDescriptor.h>
 #import <react/components/image/ImageEventEmitter.h>
-#import <react/components/image/ImageLocalData.h>
 #import <react/components/image/ImageProps.h>
 #import <react/imagemanager/ImageInstrumentation.h>
 #import <react/imagemanager/ImageRequest.h>
@@ -26,7 +25,7 @@
 
 @implementation RCTImageComponentView {
   UIImageView *_imageView;
-  SharedImageLocalData _imageLocalData;
+  ImageShadowNode::ConcreteState::Shared _state;
   ImageResponseObserverCoordinator const *_coordinator;
   RCTImageResponseObserverProxy _imageResponseObserverProxy;
 }
@@ -80,34 +79,28 @@
   [super updateProps:props oldProps:oldProps];
 }
 
-- (void)updateLocalData:(SharedLocalData)localData oldLocalData:(SharedLocalData)oldLocalData
+- (void)updateState:(facebook::react::State::Shared const &)state
+           oldState:(facebook::react::State::Shared const &)oldState
 {
-  auto imageLocalData = std::static_pointer_cast<ImageLocalData const>(localData);
+  _state = std::static_pointer_cast<ImageShadowNode::ConcreteState const>(state);
+  auto _oldState = std::static_pointer_cast<ImageShadowNode::ConcreteState const>(oldState);
+  auto data = _state->getData();
 
-  // This call (setting `coordinator`) must be unconditional (at the same block as setting `LocalData`)
-  // because the setter stores a raw pointer to object that `LocalData` owns.
-  self.coordinator = imageLocalData ? &imageLocalData->getImageRequest().getObserverCoordinator() : nullptr;
+  // This call (setting `coordinator`) must be unconditional (at the same block as setting `State`)
+  // because the setter stores a raw pointer to object that `State` owns.
+  self.coordinator = &data.getImageRequest().getObserverCoordinator();
 
-  auto previousData = _imageLocalData;
-  _imageLocalData = imageLocalData;
+  bool havePreviousData = _oldState && _oldState->getData().getImageSource() != ImageSource{};
 
-  if (!_imageLocalData) {
-    // This might happen in very rare cases (e.g. inside a subtree inside a node with `display: none`).
-    // That's quite normal.
-    return;
-  }
-
-  bool havePreviousData = previousData != nullptr;
-
-  if (!havePreviousData || _imageLocalData->getImageSource() != previousData->getImageSource()) {
+  if (!havePreviousData || data.getImageSource() != _oldState->getData().getImageSource()) {
     // Loading actually starts a little before this, but this is the first time we know
     // the image is loading and can fire an event from this component
     std::static_pointer_cast<ImageEventEmitter const>(_eventEmitter)->onLoadStart();
 
     // TODO (T58941612): Tracking for visibility should be done directly on this class.
     // For now, we consolidate instrumentation logic in the image loader, so that pre-Fabric gets the same treatment.
-    auto instrumentation = std::static_pointer_cast<const RCTImageInstrumentationProxy>(
-        _imageLocalData->getImageRequest().getSharedImageInstrumentation());
+    auto instrumentation = std::static_pointer_cast<RCTImageInstrumentationProxy const>(
+        data.getImageRequest().getSharedImageInstrumentation());
     instrumentation->trackNativeImageView(self);
   }
 }
@@ -128,7 +121,7 @@
   [super prepareForRecycle];
   self.coordinator = nullptr;
   _imageView.image = nil;
-  _imageLocalData.reset();
+  _state.reset();
 }
 
 - (void)dealloc
@@ -171,7 +164,7 @@
   self->_imageView.layer.minificationFilter = kCAFilterTrilinear;
   self->_imageView.layer.magnificationFilter = kCAFilterTrilinear;
 
-  _imageLocalData->getImageRequest().getImageInstrumentation().didSetImage();
+  _state->getData().getImageRequest().getImageInstrumentation().didSetImage();
 }
 
 - (void)didReceiveProgress:(float)progress fromObserver:(void const *)observer

ReactCommon/fabric/components/image/ImageLocalData.cpp

@@ -1,37 +0,0 @@
-/*
- * Copyright (c) Facebook, Inc. and its affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-#include "ImageLocalData.h"
-
-#include <react/components/image/conversions.h>
-#include <react/debug/debugStringConvertibleUtils.h>
-
-namespace facebook {
-namespace react {
-
-ImageSource ImageLocalData::getImageSource() const {
-  return imageSource_;
-}
-
-const ImageRequest &ImageLocalData::getImageRequest() const {
-  return imageRequest_;
-}
-
-#pragma mark - DebugStringConvertible
-
-#if RN_DEBUG_STRING_CONVERTIBLE
-std::string ImageLocalData::getDebugName() const {
-  return "ImageLocalData";
-}
-
-SharedDebugStringConvertibleList ImageLocalData::getDebugProps() const {
-  return {debugStringConvertibleItem("imageSource", imageSource_)};
-}
-#endif
-
-} // namespace react
-} // namespace facebook

ReactCommon/fabric/components/image/ImageLocalData.h

@@ -1,54 +0,0 @@
-/*
- * Copyright (c) Facebook, Inc. and its affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-#pragma once
-
-#include <react/core/LocalData.h>
-#include <react/imagemanager/ImageRequest.h>
-#include <react/imagemanager/primitives.h>
-
-namespace facebook {
-namespace react {
-
-class ImageLocalData;
-
-using SharedImageLocalData = std::shared_ptr<const ImageLocalData>;
-
-/*
- * LocalData for <Image> component.
- * Represents the image request state and (possible) retrieved image bitmap.
- */
-class ImageLocalData : public LocalData {
- public:
-  ImageLocalData(const ImageSource &imageSource, ImageRequest imageRequest)
-      : imageSource_(imageSource), imageRequest_(std::move(imageRequest)){};
-
-  /*
-   * Returns stored ImageSource object.
-   */
-  ImageSource getImageSource() const;
-
-  /*
-   * Exposes for reading stored `ImageRequest` object.
-   * `ImageRequest` object cannot be copied or moved from `ImageLocalData`.
-   */
-  const ImageRequest &getImageRequest() const;
-
-#pragma mark - DebugStringConvertible
-
-#if RN_DEBUG_STRING_CONVERTIBLE
-  std::string getDebugName() const override;
-  SharedDebugStringConvertibleList getDebugProps() const override;
-#endif
-
- private:
-  ImageSource imageSource_;
-  ImageRequest imageRequest_;
-};
-
-} // namespace react
-} // namespace facebook

ReactCommon/fabric/components/image/ImageShadowNode.cpp

@@ -8,9 +8,9 @@
 #include <cstdlib>
 #include <limits>
 
-#include <react/components/image/ImageLocalData.h>
 #include <react/components/image/ImageShadowNode.h>
 #include <react/core/LayoutContext.h>
+#include "ImageState.h"
 
 namespace facebook {
 namespace react {
@@ -22,27 +22,19 @@ void ImageShadowNode::setImageManager(const SharedImageManager &imageManager) {
   imageManager_ = imageManager;
 }
 
-void ImageShadowNode::updateLocalData() {
-  const auto &imageSource = getImageSource();
-  const auto &currentLocalData = getLocalData();
-  if (currentLocalData) {
-    assert(std::dynamic_pointer_cast<const ImageLocalData>(currentLocalData));
-    auto currentImageLocalData =
-        std::static_pointer_cast<const ImageLocalData>(currentLocalData);
-    if (currentImageLocalData->getImageSource() == imageSource) {
-      // Same `imageSource` is already in `localData`,
-      // no need to (re)request an image resource.
-      return;
-    }
-  }
-
-  // Now we are about to mutate the Shadow Node.
+void ImageShadowNode::updateStateIfNeeded() {
   ensureUnsealed();
 
-  auto imageRequest = imageManager_->requestImage(imageSource, getSurfaceId());
-  auto imageLocalData =
-      std::make_shared<ImageLocalData>(imageSource, std::move(imageRequest));
-  setLocalData(imageLocalData);
+  auto const &imageSource = getImageSource();
+  auto const &currentState = getStateData();
+
+  if (currentState.getImageSource() == imageSource) {
+    return;
+  }
+
+  auto state = ImageState{
+      imageSource, imageManager_->requestImage(imageSource, getSurfaceId())};
+  setStateData(std::move(state));
 }
 
 ImageSource ImageShadowNode::getImageSource() const {
@@ -86,7 +78,7 @@ ImageSource ImageShadowNode::getImageSource() const {
 #pragma mark - LayoutableShadowNode
 
 void ImageShadowNode::layout(LayoutContext layoutContext) {
-  updateLocalData();
+  updateStateIfNeeded();
   ConcreteViewShadowNode::layout(layoutContext);
 }
 

ReactCommon/fabric/components/image/ImageShadowNode.h

@@ -9,6 +9,7 @@
 
 #include <react/components/image/ImageEventEmitter.h>
 #include <react/components/image/ImageProps.h>
+#include <react/components/image/ImageState.h>
 #include <react/components/view/ConcreteViewShadowNode.h>
 #include <react/imagemanager/ImageManager.h>
 #include <react/imagemanager/primitives.h>
@@ -24,7 +25,8 @@ extern const char ImageComponentName[];
 class ImageShadowNode final : public ConcreteViewShadowNode<
                                   ImageComponentName,
                                   ImageProps,
-                                  ImageEventEmitter> {
+                                  ImageEventEmitter,
+                                  ImageState> {
  public:
   using ConcreteViewShadowNode::ConcreteViewShadowNode;
 
@@ -38,14 +40,11 @@ class ImageShadowNode final : public ConcreteViewShadowNode<
   void layout(LayoutContext layoutContext) override;
 
  private:
-  /*
-   * (Re)Creates a `LocalData` object (with `ImageRequest`) if needed.
-   */
-  void updateLocalData();
-
   ImageSource getImageSource() const;
 
   SharedImageManager imageManager_;
+
+  void updateStateIfNeeded();
 };
 
 } // namespace react

ReactCommon/fabric/components/image/ImageState.cpp

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "ImageState.h"
+
+namespace facebook {
+namespace react {
+
+ImageSource ImageState::getImageSource() const {
+  return imageSource_;
+}
+
+ImageRequest const &ImageState::getImageRequest() const {
+  return *imageRequest_;
+}
+
+} // namespace react
+} // namespace facebook

ReactCommon/fabric/components/image/ImageState.h

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <folly/dynamic.h>
+#include <react/imagemanager/ImageRequest.h>
+#include <react/imagemanager/primitives.h>
+
+namespace facebook {
+namespace react {
+
+/*
+ * State for <Image> component.
+ */
+class ImageState final {
+ public:
+  ImageState(ImageSource const &imageSource, ImageRequest imageRequest)
+      : imageSource_(imageSource),
+        imageRequest_(
+            std::make_shared<ImageRequest>(std::move(imageRequest))){};
+
+  ImageState() = default;
+
+  /*
+   * Returns stored ImageSource object.
+   */
+  ImageSource getImageSource() const;
+
+  /*
+   * Exposes for reading stored `ImageRequest` object.
+   * `ImageRequest` object cannot be copied or moved from `ImageLocalData`.
+   */
+  ImageRequest const &getImageRequest() const;
+
+#ifdef ANDROID
+  ImageState(ImageState const &previousState, folly::dynamic data){};
+
+  /*
+   * Empty implementation for Android because it doesn't use this class.
+   */
+  folly::dynamic getDynamic() const {
+    return {};
+  };
+#endif
+
+ private:
+  ImageSource imageSource_;
+  std::shared_ptr<ImageRequest> imageRequest_;
+};
+
+} // namespace react
+} // namespace facebook