Delete RawProps assignment operators (#49030)

Summary:
Pull Request resolved: #49030

Overwriting another RawProps object via `operator=` is rarely what we want, and these objects should be considered immutable once constructed.

This will catch issues such as D68633985

Changelog: [General][Changed] Removed `RawProps::operator=`

Reviewed By: sammy-SC

Differential Revision: D68797484

fbshipit-source-id: 766a65db1dbf4485c78007f8f69cc9426d27a943

packages/react-native/ReactCommon/react/renderer/core/RawProps.cpp

@@ -104,10 +104,6 @@ inline bool isYogaStyleProp(const std::string& prop) {
 }
 } // namespace
 
-RawProps::RawProps() {
-  mode_ = Mode::Empty;
-}
-
 /*
  * Creates an object with given `runtime` and `value`.
  */
@@ -149,18 +145,6 @@ RawProps::RawProps(const RawProps& other) noexcept {
   ignoreYogaStyleProps_ = other.ignoreYogaStyleProps_;
 }
 
-RawProps& RawProps::operator=(const RawProps& other) noexcept {
-  mode_ = other.mode_;
-  if (mode_ == Mode::JSI) {
-    runtime_ = other.runtime_;
-    value_ = jsi::Value(*runtime_, other.value_);
-  } else if (mode_ == Mode::Dynamic) {
-    dynamic_ = other.dynamic_;
-  }
-  ignoreYogaStyleProps_ = other.ignoreYogaStyleProps_;
-  return *this;
-}
-
 void RawProps::parse(const RawPropsParser& parser) noexcept {
   react_native_assert(parser_ == nullptr && "A parser was already assigned.");
   parser_ = &parser;

packages/react-native/ReactCommon/react/renderer/core/RawProps.h

@@ -43,18 +43,18 @@ class RawProps final {
   /*
    * Creates empty RawProps objects.
    */
-  RawProps();
+  RawProps() : mode_(Mode::Empty) {}
 
   /*
    * Creates an object with given `runtime` and `value`.
    */
   RawProps(jsi::Runtime& runtime, const jsi::Value& value) noexcept;
 
   explicit RawProps(const RawProps& rawProps) noexcept;
-  RawProps& operator=(const RawProps& other) noexcept;
-
   RawProps(RawProps&& other) noexcept = default;
-  RawProps& operator=(RawProps&& other) noexcept = default;
+
+  RawProps& operator=(const RawProps& other) noexcept = delete;
+  RawProps& operator=(RawProps&& other) noexcept = delete;
 
   /*
    * Creates an object with given `folly::dynamic` object.
@@ -112,8 +112,9 @@ class RawProps final {
   /*
    * Source artefacts:
    */
+
   // Mode
-  mutable Mode mode_;
+  Mode mode_;
 
   // Case 1: Source data is represented as `jsi::Object`.
   jsi::Runtime* runtime_{};