C++ - better => butter

Summary:
Renaming the `better` utilities to `butter`:
- to prevent claims that this library is superior to others - it really depends on use cases
- to indicate ease of use throughout the codebase, easily spread like butter

Changelog: [C++][Changed] Renaming C++ better util to butter, used by Fabric internals

Reviewed By: JoshuaGross

Differential Revision: D33242764

fbshipit-source-id: 26dc95d9597c61ce8e66708e44ed545e0fc5cff5

React/Fabric/Mounting/ComponentViews/TextInput/RCTTextInputUtils.h

@@ -8,7 +8,7 @@
 #import <UIKit/UIKit.h>
 
 #import <React/RCTBackedTextInputViewProtocol.h>
-#import <better/optional.h>
+#import <butter/optional.h>
 #import <react/renderer/components/iostextinput/primitives.h>
 
 NS_ASSUME_NONNULL_BEGIN
@@ -17,7 +17,7 @@ void RCTCopyBackedTextInput(
     UIView<RCTBackedTextInputViewProtocol> *fromTextInput,
     UIView<RCTBackedTextInputViewProtocol> *toTextInput);
 
-UITextAutocorrectionType RCTUITextAutocorrectionTypeFromOptionalBool(facebook::better::optional<bool> autoCorrect);
+UITextAutocorrectionType RCTUITextAutocorrectionTypeFromOptionalBool(facebook::butter::optional<bool> autoCorrect);
 
 UITextAutocapitalizationType RCTUITextAutocapitalizationTypeFromAutocapitalizationType(
     facebook::react::AutocapitalizationType autocapitalizationType);
@@ -25,7 +25,7 @@ UITextAutocapitalizationType RCTUITextAutocapitalizationTypeFromAutocapitalizati
 UIKeyboardAppearance RCTUIKeyboardAppearanceFromKeyboardAppearance(
     facebook::react::KeyboardAppearance keyboardAppearance);
 
-UITextSpellCheckingType RCTUITextSpellCheckingTypeFromOptionalBool(facebook::better::optional<bool> spellCheck);
+UITextSpellCheckingType RCTUITextSpellCheckingTypeFromOptionalBool(facebook::butter::optional<bool> spellCheck);
 
 UITextFieldViewMode RCTUITextFieldViewModeFromTextInputAccessoryVisibilityMode(
     facebook::react::TextInputAccessoryVisibilityMode mode);

React/Fabric/Mounting/ComponentViews/TextInput/RCTTextInputUtils.mm

@@ -51,7 +51,7 @@ void RCTCopyBackedTextInput(
   [toTextInput setSelectedTextRange:fromTextInput.selectedTextRange notifyDelegate:NO];
 }
 
-UITextAutocorrectionType RCTUITextAutocorrectionTypeFromOptionalBool(facebook::better::optional<bool> autoCorrect)
+UITextAutocorrectionType RCTUITextAutocorrectionTypeFromOptionalBool(facebook::butter::optional<bool> autoCorrect)
 {
   return autoCorrect.has_value() ? (*autoCorrect ? UITextAutocorrectionTypeYes : UITextAutocorrectionTypeNo)
                                  : UITextAutocorrectionTypeDefault;
@@ -84,7 +84,7 @@ UIKeyboardAppearance RCTUIKeyboardAppearanceFromKeyboardAppearance(KeyboardAppea
   }
 }
 
-UITextSpellCheckingType RCTUITextSpellCheckingTypeFromOptionalBool(facebook::better::optional<bool> spellCheck)
+UITextSpellCheckingType RCTUITextSpellCheckingTypeFromOptionalBool(facebook::butter::optional<bool> spellCheck)
 {
   return spellCheck.has_value() ? (*spellCheck ? UITextSpellCheckingTypeYes : UITextSpellCheckingTypeNo)
                                 : UITextSpellCheckingTypeDefault;

React/Fabric/Mounting/RCTComponentViewFactory.mm

@@ -10,9 +10,9 @@
 #import <React/RCTAssert.h>
 #import <React/RCTConversions.h>
 
-#import <better/map.h>
-#import <better/mutex.h>
-#import <better/set.h>
+#import <butter/map.h>
+#import <butter/mutex.h>
+#import <butter/set.h>
 
 #import <react/renderer/componentregistry/ComponentDescriptorProviderRegistry.h>
 #import <react/renderer/componentregistry/componentNameByReactViewName.h>
@@ -56,10 +56,10 @@ static Class<RCTComponentViewProtocol> RCTComponentViewClassWithName(const char
 }
 
 @implementation RCTComponentViewFactory {
-  better::map<ComponentHandle, RCTComponentViewClassDescriptor> _componentViewClasses;
-  better::set<std::string> _registeredComponentsNames;
+  butter::map<ComponentHandle, RCTComponentViewClassDescriptor> _componentViewClasses;
+  butter::set<std::string> _registeredComponentsNames;
   ComponentDescriptorProviderRegistry _providerRegistry;
-  better::shared_mutex _mutex;
+  butter::shared_mutex _mutex;
 }
 
 + (RCTComponentViewFactory *)currentComponentViewFactory
@@ -149,7 +149,7 @@ static Class<RCTComponentViewProtocol> RCTComponentViewClassWithName(const char
 - (void)registerComponentViewClass:(Class<RCTComponentViewProtocol>)componentViewClass
 {
   RCTAssert(componentViewClass, @"RCTComponentViewFactory: Provided `componentViewClass` is `nil`.");
-  std::unique_lock<better::shared_mutex> lock(_mutex);
+  std::unique_lock<butter::shared_mutex> lock(_mutex);
 
   auto componentDescriptorProvider = [componentViewClass componentDescriptorProvider];
   _componentViewClasses[componentDescriptorProvider.handle] =
@@ -171,7 +171,7 @@ static Class<RCTComponentViewProtocol> RCTComponentViewClassWithName(const char
 - (RCTComponentViewDescriptor)createComponentViewWithComponentHandle:(facebook::react::ComponentHandle)componentHandle
 {
   RCTAssertMainQueue();
-  std::shared_lock<better::shared_mutex> lock(_mutex);
+  std::shared_lock<butter::shared_mutex> lock(_mutex);
 
   auto iterator = _componentViewClasses.find(componentHandle);
   RCTAssert(
@@ -192,7 +192,7 @@ static Class<RCTComponentViewProtocol> RCTComponentViewClassWithName(const char
 - (facebook::react::ComponentDescriptorRegistry::Shared)createComponentDescriptorRegistryWithParameters:
     (facebook::react::ComponentDescriptorParameters)parameters
 {
-  std::shared_lock<better::shared_mutex> lock(_mutex);
+  std::shared_lock<butter::shared_mutex> lock(_mutex);
 
   return _providerRegistry.createComponentDescriptorRegistry(parameters);
 }

React/Fabric/Mounting/RCTComponentViewRegistry.mm

@@ -15,15 +15,15 @@
 #import "RCTParagraphComponentView.h"
 #import "RCTViewComponentView.h"
 
-#import <better/map.h>
+#import <butter/map.h>
 
 using namespace facebook::react;
 
 const NSInteger RCTComponentViewRegistryRecyclePoolMaxSize = 1024;
 
 @implementation RCTComponentViewRegistry {
-  better::map<Tag, RCTComponentViewDescriptor> _registry;
-  better::map<ComponentHandle, std::vector<RCTComponentViewDescriptor>> _recyclePool;
+  butter::map<Tag, RCTComponentViewDescriptor> _registry;
+  butter::map<ComponentHandle, std::vector<RCTComponentViewDescriptor>> _recyclePool;
 }
 
 - (instancetype)init

React/Fabric/Mounting/RCTMountingManager.mm

@@ -7,7 +7,7 @@
 
 #import "RCTMountingManager.h"
 
-#import <better/map.h>
+#import <butter/map.h>
 
 #import <React/RCTAssert.h>
 #import <React/RCTComponent.h>

React/Fabric/Mounting/RCTMountingTransactionObserverCoordinator.h

@@ -8,8 +8,8 @@
 #import <React/RCTComponentViewDescriptor.h>
 #import "RCTMountingTransactionObserverCoordinator.h"
 
-#import <better/map.h>
-#import <better/set.h>
+#import <butter/map.h>
+#import <butter/set.h>
 
 #import <react/renderer/mounting/MountingTransactionMetadata.h>
 
@@ -36,8 +36,8 @@ class RCTMountingTransactionObserverCoordinator final {
       facebook::react::MountingTransactionMetadata const &metadata) const;
 
  private:
-  facebook::better::map<
+  facebook::butter::map<
       facebook::react::SurfaceId,
-      facebook::better::set<RCTComponentViewDescriptor>>
+      facebook::butter::set<RCTComponentViewDescriptor>>
       registry_;
 };

React/Fabric/RCTSurfacePresenter.mm

@@ -79,7 +79,7 @@ static BackgroundExecutor RCTGetBackgroundExecutor()
   ContextContainer::Shared _contextContainer; // Protected by `_schedulerLifeCycleMutex`.
   RuntimeExecutor _runtimeExecutor; // Protected by `_schedulerLifeCycleMutex`.
 
-  better::shared_mutex _observerListMutex;
+  butter::shared_mutex _observerListMutex;
   NSMutableArray<id<RCTSurfacePresenterObserver>> *_observers;
 }
 
@@ -365,13 +365,13 @@ static BackgroundExecutor RCTGetBackgroundExecutor()
 
 - (void)addObserver:(id<RCTSurfacePresenterObserver>)observer
 {
-  std::unique_lock<better::shared_mutex> lock(_observerListMutex);
+  std::unique_lock<butter::shared_mutex> lock(_observerListMutex);
   [self->_observers addObject:observer];
 }
 
 - (void)removeObserver:(id<RCTSurfacePresenterObserver>)observer
 {
-  std::unique_lock<better::shared_mutex> lock(_observerListMutex);
+  std::unique_lock<butter::shared_mutex> lock(_observerListMutex);
   [self->_observers removeObject:observer];
 }
 
@@ -381,7 +381,7 @@ static BackgroundExecutor RCTGetBackgroundExecutor()
 {
   RCTAssertMainQueue();
 
-  std::shared_lock<better::shared_mutex> lock(_observerListMutex);
+  std::shared_lock<butter::shared_mutex> lock(_observerListMutex);
   for (id<RCTSurfacePresenterObserver> observer in _observers) {
     if ([observer respondsToSelector:@selector(willMountComponentsWithRootTag:)]) {
       [observer willMountComponentsWithRootTag:rootTag];
@@ -393,7 +393,7 @@ static BackgroundExecutor RCTGetBackgroundExecutor()
 {
   RCTAssertMainQueue();
 
-  std::shared_lock<better::shared_mutex> lock(_observerListMutex);
+  std::shared_lock<butter::shared_mutex> lock(_observerListMutex);
   for (id<RCTSurfacePresenterObserver> observer in _observers) {
     if ([observer respondsToSelector:@selector(didMountComponentsWithRootTag:)]) {
       [observer didMountComponentsWithRootTag:rootTag];

React/Fabric/RCTSurfaceRegistry.mm

@@ -7,7 +7,7 @@
 
 #import "RCTSurfaceRegistry.h"
 
-#import <better/mutex.h>
+#import <butter/mutex.h>
 #import <mutex>
 #import <shared_mutex>
 
@@ -16,7 +16,7 @@
 using namespace facebook;
 
 @implementation RCTSurfaceRegistry {
-  better::shared_mutex _mutex;
+  butter::shared_mutex _mutex;
   NSMapTable<id, RCTFabricSurface *> *_registry;
 }
 
@@ -32,13 +32,13 @@ using namespace facebook;
 
 - (void)enumerateWithBlock:(RCTSurfaceEnumeratorBlock)block
 {
-  std::shared_lock<better::shared_mutex> lock(_mutex);
+  std::shared_lock<butter::shared_mutex> lock(_mutex);
   block([_registry objectEnumerator]);
 }
 
 - (void)registerSurface:(RCTFabricSurface *)surface
 {
-  std::unique_lock<better::shared_mutex> lock(_mutex);
+  std::unique_lock<butter::shared_mutex> lock(_mutex);
 
   ReactTag rootTag = surface.rootViewTag.integerValue;
   [_registry setObject:surface forKey:(__bridge id)(void *)rootTag];
@@ -46,7 +46,7 @@ using namespace facebook;
 
 - (void)unregisterSurface:(RCTFabricSurface *)surface
 {
-  std::unique_lock<better::shared_mutex> lock(_mutex);
+  std::unique_lock<butter::shared_mutex> lock(_mutex);
 
   ReactTag rootTag = surface.rootViewTag.integerValue;
   [_registry removeObjectForKey:(__bridge id)(void *)rootTag];
@@ -54,7 +54,7 @@ using namespace facebook;
 
 - (RCTFabricSurface *)surfaceForRootTag:(ReactTag)rootTag
 {
-  std::shared_lock<better::shared_mutex> lock(_mutex);
+  std::shared_lock<butter::shared_mutex> lock(_mutex);
 
   return [_registry objectForKey:(__bridge id)(void *)rootTag];
 }

React/Fabric/Surface/RCTFabricSurface.mm

@@ -34,7 +34,7 @@ using namespace facebook::react;
   // `SurfaceHandler` is a thread-safe object, so we don't need additional synchronization.
   // Objective-C++ classes cannot have instance variables without default constructors,
   // hence we wrap a value into `optional` to workaround it.
-  better::optional<SurfaceHandler> _surfaceHandler;
+  butter::optional<SurfaceHandler> _surfaceHandler;
 
   // Protects Surface's start and stop processes.
   // Even though SurfaceHandler is tread-safe, it will crash if we try to stop a surface that is not running.

ReactAndroid/src/main/java/com/facebook/react/fabric/jni/Android.mk

@@ -12,7 +12,7 @@ LOCAL_MODULE := fabricjni
 LOCAL_SRC_FILES := $(wildcard $(LOCAL_PATH)/*.cpp)
 
 LOCAL_SHARED_LIBRARIES := \
-  libbetter \
+  libbutter \
   libfb \
   libfbjni \
   libfolly_futures \

ReactAndroid/src/main/java/com/facebook/react/fabric/jni/Binding.cpp

@@ -46,7 +46,7 @@ jni::local_ref<Binding::jhybriddata> Binding::initHybrid(
 
 // Thread-safe getter
 std::shared_ptr<Scheduler> Binding::getScheduler() {
-  std::shared_lock<better::shared_mutex> lock(installMutex_);
+  std::shared_lock<butter::shared_mutex> lock(installMutex_);
   return scheduler_;
 }
 
@@ -128,7 +128,7 @@ void Binding::startSurface(
 
   {
     SystraceSection s2("FabricUIManagerBinding::startSurface::surfaceId::lock");
-    std::unique_lock<better::shared_mutex> lock(surfaceHandlerRegistryMutex_);
+    std::unique_lock<butter::shared_mutex> lock(surfaceHandlerRegistryMutex_);
     SystraceSection s3("FabricUIManagerBinding::startSurface::surfaceId");
     surfaceHandlerRegistry_.emplace(surfaceId, std::move(surfaceHandler));
   }
@@ -191,7 +191,7 @@ void Binding::startSurfaceWithConstraints(
   {
     SystraceSection s2(
         "FabricUIManagerBinding::startSurfaceWithConstraints::surfaceId::lock");
-    std::unique_lock<better::shared_mutex> lock(surfaceHandlerRegistryMutex_);
+    std::unique_lock<butter::shared_mutex> lock(surfaceHandlerRegistryMutex_);
     SystraceSection s3(
         "FabricUIManagerBinding::startSurfaceWithConstraints::surfaceId");
     surfaceHandlerRegistry_.emplace(surfaceId, std::move(surfaceHandler));
@@ -228,7 +228,7 @@ void Binding::stopSurface(jint surfaceId) {
   }
 
   {
-    std::unique_lock<better::shared_mutex> lock(surfaceHandlerRegistryMutex_);
+    std::unique_lock<butter::shared_mutex> lock(surfaceHandlerRegistryMutex_);
 
     auto iterator = surfaceHandlerRegistry_.find(surfaceId);
 
@@ -289,7 +289,7 @@ void Binding::setConstraints(
       isRTL ? LayoutDirection::RightToLeft : LayoutDirection::LeftToRight;
 
   {
-    std::shared_lock<better::shared_mutex> lock(surfaceHandlerRegistryMutex_);
+    std::shared_lock<butter::shared_mutex> lock(surfaceHandlerRegistryMutex_);
 
     auto iterator = surfaceHandlerRegistry_.find(surfaceId);
 
@@ -334,7 +334,7 @@ void Binding::installFabricUIManager(
 
   // Use std::lock and std::adopt_lock to prevent deadlocks by locking mutexes
   // at the same time
-  std::unique_lock<better::shared_mutex> lock(installMutex_);
+  std::unique_lock<butter::shared_mutex> lock(installMutex_);
 
   auto globalJavaUiManager = make_global(javaUIManager);
   mountingManager_ =
@@ -434,7 +434,7 @@ void Binding::uninstallFabricUIManager() {
                  << this << ").";
   }
 
-  std::unique_lock<better::shared_mutex> lock(installMutex_);
+  std::unique_lock<butter::shared_mutex> lock(installMutex_);
   animationDriver_ = nullptr;
   scheduler_ = nullptr;
   mountingManager_ = nullptr;
@@ -443,7 +443,7 @@ void Binding::uninstallFabricUIManager() {
 
 std::shared_ptr<FabricMountingManager> Binding::verifyMountingManager(
     std::string const &hint) {
-  std::shared_lock<better::shared_mutex> lock(installMutex_);
+  std::shared_lock<butter::shared_mutex> lock(installMutex_);
   if (!mountingManager_) {
     LOG(ERROR) << hint << " mounting manager disappeared.";
   }

ReactAndroid/src/main/java/com/facebook/react/fabric/jni/Binding.h

@@ -129,7 +129,7 @@ class Binding : public jni::HybridClass<Binding>,
   void uninstallFabricUIManager();
 
   // Private member variables
-  better::shared_mutex installMutex_;
+  butter::shared_mutex installMutex_;
   std::shared_ptr<FabricMountingManager> mountingManager_;
   std::shared_ptr<Scheduler> scheduler_;
 
@@ -145,8 +145,8 @@ class Binding : public jni::HybridClass<Binding>,
 
   std::unique_ptr<JBackgroundExecutor> backgroundExecutor_;
 
-  better::map<SurfaceId, SurfaceHandler> surfaceHandlerRegistry_{};
-  better::shared_mutex
+  butter::map<SurfaceId, SurfaceHandler> surfaceHandlerRegistry_{};
+  butter::shared_mutex
       surfaceHandlerRegistryMutex_; // Protects `surfaceHandlerRegistry_`.
 
   float pointScaleFactor_ = 1;

ReactAndroid/src/main/java/com/facebook/react/fabric/jni/SurfaceHandlerBinding.cpp

@@ -21,7 +21,7 @@ void SurfaceHandlerBinding::setDisplayMode(jint mode) {
 }
 
 void SurfaceHandlerBinding::start() {
-  std::unique_lock<better::shared_mutex> lock(lifecycleMutex_);
+  std::unique_lock<butter::shared_mutex> lock(lifecycleMutex_);
 
   if (surfaceHandler_.getStatus() != SurfaceHandler::Status::Running) {
     surfaceHandler_.start();
@@ -29,7 +29,7 @@ void SurfaceHandlerBinding::start() {
 }
 
 void SurfaceHandlerBinding::stop() {
-  std::unique_lock<better::shared_mutex> lock(lifecycleMutex_);
+  std::unique_lock<butter::shared_mutex> lock(lifecycleMutex_);
 
   if (surfaceHandler_.getStatus() == SurfaceHandler::Status::Running) {
     surfaceHandler_.stop();

ReactAndroid/src/main/java/com/facebook/react/fabric/jni/SurfaceHandlerBinding.h

@@ -50,7 +50,7 @@ class SurfaceHandlerBinding : public jni::HybridClass<SurfaceHandlerBinding> {
   SurfaceHandler const &getSurfaceHandler();
 
  private:
-  mutable better::shared_mutex lifecycleMutex_;
+  mutable butter::shared_mutex lifecycleMutex_;
   const SurfaceHandler surfaceHandler_;
 
   jni::alias_ref<SurfaceHandlerBinding::jhybriddata> jhybridobject_;

ReactAndroid/src/main/jni/react/jni/Android.mk

@@ -130,7 +130,7 @@ include $(BUILD_SHARED_LIBRARY)
 #   Whenever you encounter an include <dir>/<module-dir>/Android.mk, you
 #   tell andorid-ndk to compile the module in <dir>/<module-dir> according
 #   to the specification inside <dir>/<module-dir>/Android.mk.
-$(call import-module,better)
+$(call import-module,butter)
 $(call import-module,folly)
 $(call import-module,fb)
 $(call import-module,fbjni)

ReactCommon/React-Fabric.podspec

@@ -61,12 +61,12 @@ Pod::Spec.new do |s|
     ss.pod_target_xcconfig  = { "HEADER_SEARCH_PATHS" => "\"$(PODS_TARGET_SRCROOT)/ReactCommon\" \"$(PODS_ROOT)/RCT-Folly\"" }
   end
 
-  s.subspec "better" do |ss|
+  s.subspec "butter" do |ss|
     ss.dependency             folly_dep_name, folly_version
     ss.compiler_flags       = folly_compiler_flags
-    ss.source_files         = "better/**/*.{m,mm,cpp,h}"
-    ss.exclude_files        = "better/tests"
-    ss.header_dir           = "better"
+    ss.source_files         = "butter/**/*.{m,mm,cpp,h}"
+    ss.exclude_files        = "butter/tests"
+    ss.header_dir           = "butter"
     ss.pod_target_xcconfig  = { "HEADER_SEARCH_PATHS" => "\"$(PODS_TARGET_SRCROOT)/ReactCommon\" \"$(PODS_ROOT)/RCT-Folly\"" }
   end
 

ReactCommon/butter/Android.mk

@@ -7,7 +7,7 @@ LOCAL_PATH := $(call my-dir)
 
 include $(CLEAR_VARS)
 
-LOCAL_MODULE := better
+LOCAL_MODULE := butter
 
 LOCAL_SRC_FILES := $(wildcard $(LOCAL_PATH)/*.cpp)
 
@@ -15,7 +15,7 @@ LOCAL_C_INCLUDES := $(LOCAL_PATH)/
 LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/
 
 LOCAL_CFLAGS := \
-  -DLOG_TAG=\"Better\"
+  -DLOG_TAG=\"Butter\"
 
 LOCAL_CFLAGS += -fexceptions -frtti -std=c++17 -Wall
 

ReactCommon/butter/BUCK

@@ -13,7 +13,7 @@ load(
 APPLE_COMPILER_FLAGS = get_apple_compiler_flags()
 
 rn_xplat_cxx_library(
-    name = "better",
+    name = "butter",
     srcs = glob(
         ["**/*.cpp"],
         exclude = glob(["tests/**/*.cpp"]),
@@ -27,7 +27,7 @@ rn_xplat_cxx_library(
         [
             ("", "*.h"),
         ],
-        prefix = "better",
+        prefix = "butter",
     ),
     fbobjc_compiler_flags = APPLE_COMPILER_FLAGS,
     fbobjc_preprocessor_flags = get_preprocessor_flags_for_build_mode() + get_apple_inspector_flags(),

ReactCommon/butter/butter.h

@@ -8,20 +8,20 @@
 #pragma once
 
 namespace facebook {
-namespace better {
+namespace butter {
 
 /*
- * `Better` is a trivial collection of basic tools borrowed from other low-level
+ * `Butter` is a trivial collection of basic tools borrowed from other low-level
  * general purpose libraries (like Folly, Abseil or Boost). The main goals of
- * Better:
+ * Butter:
  * - Make the codebase more portable;
  * - Make the dependency list explicit (by decoupling it as a dependency list of
- * Better);
+ * Butter);
  * - Make relying on modern C++ patterns and tools in code simple and easy.
  * - Make executing experiments with different dependencies easier.
  *
- * What should be part of Better and what should not? Should I add some piece of
- * functionality in the Better? Here is a quick checklist.
+ * What should be part of Butter and what should not? Should I add some piece of
+ * functionality in the Butter? Here is a quick checklist.
  *
  * If one of the following is true, yes, go for it:
  * - If some feature is already in some future C++ standard (possibly in draft
@@ -55,8 +55,8 @@ namespace better {
  * introspections mechanisms.
  */
 #ifndef DEBUG
-#define BETTER_USE_FOLLY_CONTAINERS
+#define BUTTER_USE_FOLLY_CONTAINERS
 #endif
 
-} // namespace better
+} // namespace butter
 } // namespace facebook

ReactCommon/butter/map.h

@@ -7,9 +7,9 @@
 
 #pragma once
 
-#include <better/better.h>
+#include <butter/butter.h>
 
-#ifdef BETTER_USE_FOLLY_CONTAINERS
+#ifdef BUTTER_USE_FOLLY_CONTAINERS
 
 #include <folly/container/F14Map.h>
 
@@ -20,16 +20,16 @@
 #endif
 
 namespace facebook {
-namespace better {
+namespace butter {
 
 /*
- * Note: In Better, `map` aliases to `unorderd_map` because everyone agrees that
+ * Note: In Butter, `map` aliases to `unorderd_map` because everyone agrees that
  * an *ordered* map is nonsense and was a huge mistake for standardization. If
  * you need an *ordered* map, feel free to introduce that as
- * `better::ordered_map`.
+ * `butter::ordered_map`.
  */
 
-#ifdef BETTER_USE_FOLLY_CONTAINERS
+#ifdef BUTTER_USE_FOLLY_CONTAINERS
 
 template <typename... Ts>
 using map = folly::F14FastMap<Ts...>;
@@ -41,5 +41,5 @@ using map = std::unordered_map<Ts...>;
 
 #endif
 
-} // namespace better
+} // namespace butter
 } // namespace facebook

ReactCommon/butter/mutex.h

@@ -12,9 +12,9 @@
 #include <shared_mutex>
 
 namespace facebook {
-namespace better {
+namespace butter {
 
 using shared_mutex = folly::SharedMutex;
 
-} // namespace better
+} // namespace butter
 } // namespace facebook

ReactCommon/butter/optional.h

@@ -7,9 +7,9 @@
 
 #pragma once
 
-#include <better/better.h>
+#include <butter/butter.h>
 
-#if defined(BETTER_USE_FOLLY_CONTAINERS) || __cplusplus < 202000L
+#if defined(BUTTER_USE_FOLLY_CONTAINERS) || __cplusplus < 202000L
 
 #include <folly/Optional.h>
 
@@ -20,9 +20,9 @@
 #endif
 
 namespace facebook {
-namespace better {
+namespace butter {
 
-#if defined(BETTER_USE_FOLLY_CONTAINERS) || __cplusplus < 202000L
+#if defined(BUTTER_USE_FOLLY_CONTAINERS) || __cplusplus < 202000L
 
 template <typename Value>
 using optional = folly::Optional<Value>;
@@ -34,5 +34,5 @@ using optional = std::optional<Value>;
 
 #endif
 
-} // namespace better
+} // namespace butter
 } // namespace facebook

ReactCommon/butter/set.h

@@ -7,9 +7,9 @@
 
 #pragma once
 
-#include <better/better.h>
+#include <butter/butter.h>
 
-#ifdef BETTER_USE_FOLLY_CONTAINERS
+#ifdef BUTTER_USE_FOLLY_CONTAINERS
 
 #include <folly/container/F14Set.h>
 
@@ -20,9 +20,9 @@
 #endif
 
 namespace facebook {
-namespace better {
+namespace butter {
 
-#ifdef BETTER_USE_FOLLY_CONTAINERS
+#ifdef BUTTER_USE_FOLLY_CONTAINERS
 
 template <typename... Ts>
 using set = folly::F14FastSet<Ts...>;
@@ -34,5 +34,5 @@ using set = std::unordered_set<Ts...>;
 
 #endif
 
-} // namespace better
+} // namespace butter
 } // namespace facebook

ReactCommon/butter/small_vector.h

@@ -7,10 +7,10 @@
 
 #pragma once
 
-#include <better/better.h>
+#include <butter/butter.h>
 
 // `folly::small_vector` is broken on some versions of Android.
-#if defined(BETTER_USE_FOLLY_CONTAINERS) && !defined(ANDROID)
+#if defined(BUTTER_USE_FOLLY_CONTAINERS) && !defined(ANDROID)
 
 #include <folly/small_vector.h>
 
@@ -21,9 +21,9 @@
 #endif
 
 namespace facebook {
-namespace better {
+namespace butter {
 
-#if defined(BETTER_USE_FOLLY_CONTAINERS) && !defined(ANDROID)
+#if defined(BUTTER_USE_FOLLY_CONTAINERS) && !defined(ANDROID)
 
 template <typename T, std::size_t Size, typename... Ts>
 using small_vector = folly::small_vector<T, Size, Ts...>;
@@ -35,5 +35,5 @@ using small_vector = std::vector<T, Ts...>;
 
 #endif
 
-} // namespace better
+} // namespace butter
 } // namespace facebook

ReactCommon/react/renderer/animations/LayoutAnimationKeyFrameManager.cpp

@@ -172,7 +172,7 @@ bool LayoutAnimationKeyFrameManager::shouldOverridePullTransaction() const {
   return shouldAnimateFrame();
 }
 
-better::optional<MountingTransaction>
+butter::optional<MountingTransaction>
 LayoutAnimationKeyFrameManager::pullTransaction(
     SurfaceId surfaceId,
     MountingTransaction::Number transactionNumber,
@@ -250,7 +250,7 @@ LayoutAnimationKeyFrameManager::pullTransaction(
         surfaceId, mutations, conflictingAnimations);
 
     // Are we animating this list of mutations?
-    better::optional<LayoutAnimation> currentAnimation{};
+    butter::optional<LayoutAnimation> currentAnimation{};
     {
       std::lock_guard<std::mutex> lock(currentAnimationMutex_);
       if (currentAnimation_) {
@@ -271,9 +271,9 @@ LayoutAnimationKeyFrameManager::pullTransaction(
       // TODO: to prevent this step we could tag Remove/Insert mutations as
       // being moves on the Differ level, since we know that there? We could use
       // TinyMap here, but it's not exposed by Differentiator (yet).
-      better::set<Tag> insertedTags;
-      better::set<Tag> deletedTags;
-      better::set<Tag> reparentedTags; // tags that are deleted and recreated
+      butter::set<Tag> insertedTags;
+      butter::set<Tag> deletedTags;
+      butter::set<Tag> reparentedTags; // tags that are deleted and recreated
       std::unordered_map<Tag, ShadowViewMutation> movedTags;
       for (const auto &mutation : mutations) {
         if (mutation.type == ShadowViewMutation::Type::Insert) {
@@ -320,7 +320,7 @@ LayoutAnimationKeyFrameManager::pullTransaction(
           continue;
         }
 
-        better::optional<ShadowViewMutation> executeMutationImmediately{};
+        butter::optional<ShadowViewMutation> executeMutationImmediately{};
 
         bool isRemoveReinserted =
             mutation.type == ShadowViewMutation::Type::Remove &&
@@ -1063,7 +1063,7 @@ LayoutAnimationKeyFrameManager::pullTransaction(
 
 void LayoutAnimationKeyFrameManager::uiManagerDidConfigureNextLayoutAnimation(
     LayoutAnimation layoutAnimation) const {
-  currentAnimation_ = better::optional<LayoutAnimation>{layoutAnimation};
+  currentAnimation_ = butter::optional<LayoutAnimation>{layoutAnimation};
 }
 
 void LayoutAnimationKeyFrameManager::setLayoutAnimationStatusDelegate(
@@ -1616,7 +1616,7 @@ void LayoutAnimationKeyFrameManager::deleteAnimationsForStoppedSurfaces()
 
   // Execute stopSurface on any ongoing animations
   if (inflightAnimationsExistInitially) {
-    better::set<SurfaceId> surfaceIdsToStop{};
+    butter::set<SurfaceId> surfaceIdsToStop{};
     {
       std::lock_guard<std::mutex> lock(surfaceIdsToStopMutex_);
       surfaceIdsToStop = surfaceIdsToStop_;

ReactCommon/react/renderer/animations/LayoutAnimationKeyFrameManager.h

@@ -8,8 +8,8 @@
 #pragma once
 
 #include <ReactCommon/RuntimeExecutor.h>
-#include <better/optional.h>
-#include <better/set.h>
+#include <butter/optional.h>
+#include <butter/set.h>
 #include <react/renderer/animations/LayoutAnimationCallbackWrapper.h>
 #include <react/renderer/animations/primitives.h>
 #include <react/renderer/core/RawValue.h>
@@ -67,7 +67,7 @@ class LayoutAnimationKeyFrameManager : public UIManagerAnimationDelegate,
   // This is used to "hijack" the diffing process to figure out which mutations
   // should be animated. The mutations returned by this function will be
   // executed immediately.
-  better::optional<MountingTransaction> pullTransaction(
+  butter::optional<MountingTransaction> pullTransaction(
       SurfaceId surfaceId,
       MountingTransaction::Number number,
       TransactionTelemetry const &telemetry,
@@ -95,7 +95,7 @@ class LayoutAnimationKeyFrameManager : public UIManagerAnimationDelegate,
 
  protected:
   SharedComponentDescriptorRegistry componentDescriptorRegistry_;
-  mutable better::optional<LayoutAnimation> currentAnimation_{};
+  mutable butter::optional<LayoutAnimation> currentAnimation_{};
   mutable std::mutex currentAnimationMutex_;
 
   /**
@@ -148,7 +148,7 @@ class LayoutAnimationKeyFrameManager : public UIManagerAnimationDelegate,
   mutable std::mutex layoutAnimationStatusDelegateMutex_;
   mutable LayoutAnimationStatusDelegate *layoutAnimationStatusDelegate_{};
   mutable std::mutex surfaceIdsToStopMutex_;
-  mutable better::set<SurfaceId> surfaceIdsToStop_{};
+  mutable butter::set<SurfaceId> surfaceIdsToStop_{};
   bool skipInvalidatedKeyFrames_{false};
 
   /*

ReactCommon/react/renderer/animations/conversions.h

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <react/renderer/animations/primitives.h>
 
 #include <glog/logging.h>
@@ -13,7 +13,7 @@
 namespace facebook {
 namespace react {
 
-static inline better::optional<AnimationType> parseAnimationType(
+static inline butter::optional<AnimationType> parseAnimationType(
     std::string param) {
   if (param == "spring") {
     return AnimationType::Spring;
@@ -38,7 +38,7 @@ static inline better::optional<AnimationType> parseAnimationType(
   return {};
 }
 
-static inline better::optional<AnimationProperty> parseAnimationProperty(
+static inline butter::optional<AnimationProperty> parseAnimationProperty(
     std::string param) {
   if (param == "opacity") {
     return AnimationProperty::Opacity;
@@ -57,7 +57,7 @@ static inline better::optional<AnimationProperty> parseAnimationProperty(
   return {};
 }
 
-static inline better::optional<AnimationConfig> parseAnimationConfig(
+static inline butter::optional<AnimationConfig> parseAnimationConfig(
     folly::dynamic const &config,
     double defaultDuration,
     bool parsePropertyType) {
@@ -163,7 +163,7 @@ static inline better::optional<AnimationConfig> parseAnimationConfig(
     }
   }
 
-  return better::optional<AnimationConfig>(AnimationConfig{
+  return butter::optional<AnimationConfig>(AnimationConfig{
       *animationType,
       animationProperty,
       duration,
@@ -173,7 +173,7 @@ static inline better::optional<AnimationConfig> parseAnimationConfig(
 }
 
 // Parse animation config from JS
-static inline better::optional<LayoutAnimationConfig>
+static inline butter::optional<LayoutAnimationConfig>
 parseLayoutAnimationConfig(folly::dynamic const &config) {
   if (config.empty() || !config.isObject()) {
     return {};
@@ -187,17 +187,17 @@ parseLayoutAnimationConfig(folly::dynamic const &config) {
 
   const auto createConfigIt = config.find("create");
   const auto createConfig = createConfigIt == config.items().end()
-      ? better::optional<AnimationConfig>(AnimationConfig{})
+      ? butter::optional<AnimationConfig>(AnimationConfig{})
       : parseAnimationConfig(createConfigIt->second, duration, true);
 
   const auto updateConfigIt = config.find("update");
   const auto updateConfig = updateConfigIt == config.items().end()
-      ? better::optional<AnimationConfig>(AnimationConfig{})
+      ? butter::optional<AnimationConfig>(AnimationConfig{})
       : parseAnimationConfig(updateConfigIt->second, duration, false);
 
   const auto deleteConfigIt = config.find("delete");
   const auto deleteConfig = deleteConfigIt == config.items().end()
-      ? better::optional<AnimationConfig>(AnimationConfig{})
+      ? butter::optional<AnimationConfig>(AnimationConfig{})
       : parseAnimationConfig(deleteConfigIt->second, duration, true);
 
   if (!createConfig || !updateConfig || !deleteConfig) {

ReactCommon/react/renderer/attributedstring/Android.mk

@@ -23,7 +23,7 @@ LOCAL_STATIC_LIBRARIES :=
 
 LOCAL_SHARED_LIBRARIES := \
   glog \
-  libbetter \
+  libbutter \
   libfolly_futures \
   libfolly_json \
   libglog_init \
@@ -38,7 +38,7 @@ LOCAL_SHARED_LIBRARIES := \
 
 include $(BUILD_SHARED_LIBRARY)
 
-$(call import-module,better)
+$(call import-module,butter)
 $(call import-module,glog)
 $(call import-module,folly)
 $(call import-module,fbgloginit)

ReactCommon/react/renderer/attributedstring/AttributedString.h

@@ -56,7 +56,7 @@ class AttributedString : public Sealable, public DebugStringConvertible {
     int length{0};
   };
 
-  using Fragments = better::small_vector<Fragment, 1>;
+  using Fragments = butter::small_vector<Fragment, 1>;
 
   /*
    * Appends and prepends a `fragment` to the string.

ReactCommon/react/renderer/attributedstring/TextAttributes.h

@@ -10,7 +10,7 @@
 #include <functional>
 #include <limits>
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <folly/Hash.h>
 #include <react/renderer/attributedstring/primitives.h>
 #include <react/renderer/core/LayoutPrimitives.h>
@@ -46,38 +46,38 @@ class TextAttributes : public DebugStringConvertible {
   std::string fontFamily{""};
   Float fontSize{std::numeric_limits<Float>::quiet_NaN()};
   Float fontSizeMultiplier{std::numeric_limits<Float>::quiet_NaN()};
-  better::optional<FontWeight> fontWeight{};
-  better::optional<FontStyle> fontStyle{};
-  better::optional<FontVariant> fontVariant{};
-  better::optional<bool> allowFontScaling{};
+  butter::optional<FontWeight> fontWeight{};
+  butter::optional<FontStyle> fontStyle{};
+  butter::optional<FontVariant> fontVariant{};
+  butter::optional<bool> allowFontScaling{};
   Float letterSpacing{std::numeric_limits<Float>::quiet_NaN()};
-  better::optional<TextTransform> textTransform{};
+  butter::optional<TextTransform> textTransform{};
 
   // Paragraph Styles
   Float lineHeight{std::numeric_limits<Float>::quiet_NaN()};
-  better::optional<TextAlignment> alignment{};
-  better::optional<WritingDirection> baseWritingDirection{};
+  butter::optional<TextAlignment> alignment{};
+  butter::optional<WritingDirection> baseWritingDirection{};
 
   // Decoration
   SharedColor textDecorationColor{};
-  better::optional<TextDecorationLineType> textDecorationLineType{};
-  better::optional<TextDecorationStyle> textDecorationStyle{};
+  butter::optional<TextDecorationLineType> textDecorationLineType{};
+  butter::optional<TextDecorationStyle> textDecorationStyle{};
 
   // Shadow
   // TODO: Use `Point` type instead of `Size` for `textShadowOffset` attribute.
-  better::optional<Size> textShadowOffset{};
+  butter::optional<Size> textShadowOffset{};
   Float textShadowRadius{std::numeric_limits<Float>::quiet_NaN()};
   SharedColor textShadowColor{};
 
   // Special
-  better::optional<bool> isHighlighted{};
+  butter::optional<bool> isHighlighted{};
 
   // TODO T59221129: document where this value comes from and how it is set.
   // It's not clear if this is being used properly, or if it's being set at all.
   // Currently, it is intentionally *not* being set as part of BaseTextProps
   // construction.
-  better::optional<LayoutDirection> layoutDirection{};
-  better::optional<AccessibilityRole> accessibilityRole{};
+  butter::optional<LayoutDirection> layoutDirection{};
+  butter::optional<AccessibilityRole> accessibilityRole{};
 
 #pragma mark - Operations
 

ReactCommon/react/renderer/attributedstring/conversions.h

@@ -768,7 +768,7 @@ inline void fromRawValue(
     const PropsParserContext &context,
     RawValue const &value,
     AttributedString::Range &result) {
-  auto map = (better::map<std::string, int>)value;
+  auto map = (butter::map<std::string, int>)value;
 
   auto start = map.find("start");
   if (start != map.end()) {

ReactCommon/react/renderer/componentregistry/ComponentDescriptorProviderRegistry.cpp

@@ -12,7 +12,7 @@ namespace react {
 
 void ComponentDescriptorProviderRegistry::add(
     ComponentDescriptorProvider provider) const {
-  std::unique_lock<better::shared_mutex> lock(mutex_);
+  std::unique_lock<butter::shared_mutex> lock(mutex_);
 
   /*
   // TODO: T57583139
@@ -45,7 +45,7 @@ void ComponentDescriptorProviderRegistry::add(
 void ComponentDescriptorProviderRegistry::setComponentDescriptorProviderRequest(
     ComponentDescriptorProviderRequest componentDescriptorProviderRequest)
     const {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
   componentDescriptorProviderRequest_ = componentDescriptorProviderRequest;
 }
 
@@ -54,7 +54,7 @@ void ComponentDescriptorProviderRegistry::request(
   ComponentDescriptorProviderRequest componentDescriptorProviderRequest;
 
   {
-    std::shared_lock<better::shared_mutex> lock(mutex_);
+    std::shared_lock<butter::shared_mutex> lock(mutex_);
     componentDescriptorProviderRequest = componentDescriptorProviderRequest_;
   }
 
@@ -66,7 +66,7 @@ void ComponentDescriptorProviderRegistry::request(
 ComponentDescriptorRegistry::Shared
 ComponentDescriptorProviderRegistry::createComponentDescriptorRegistry(
     ComponentDescriptorParameters const &parameters) const {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
 
   auto registry = std::make_shared<ComponentDescriptorRegistry const>(
       parameters, *this, parameters.contextContainer);

ReactCommon/react/renderer/componentregistry/ComponentDescriptorProviderRegistry.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/mutex.h>
+#include <butter/mutex.h>
 
 #include <react/renderer/componentregistry/ComponentDescriptorProvider.h>
 #include <react/renderer/componentregistry/ComponentDescriptorRegistry.h>
@@ -59,10 +59,10 @@ class ComponentDescriptorProviderRegistry final {
 
   void request(ComponentName componentName) const;
 
-  mutable better::shared_mutex mutex_;
+  mutable butter::shared_mutex mutex_;
   mutable std::vector<std::weak_ptr<ComponentDescriptorRegistry const>>
       componentDescriptorRegistries_;
-  mutable better::map<ComponentHandle, ComponentDescriptorProvider const>
+  mutable butter::map<ComponentHandle, ComponentDescriptorProvider const>
       componentDescriptorProviders_;
   mutable ComponentDescriptorProviderRequest
       componentDescriptorProviderRequest_;

ReactCommon/react/renderer/componentregistry/ComponentDescriptorRegistry.cpp

@@ -27,7 +27,7 @@ ComponentDescriptorRegistry::ComponentDescriptorRegistry(
 
 void ComponentDescriptorRegistry::add(
     ComponentDescriptorProvider componentDescriptorProvider) const {
-  std::unique_lock<better::shared_mutex> lock(mutex_);
+  std::unique_lock<butter::shared_mutex> lock(mutex_);
 
   auto componentDescriptor = componentDescriptorProvider.constructor(
       {parameters_.eventDispatcher,
@@ -58,7 +58,7 @@ void ComponentDescriptorRegistry::registerComponentDescriptor(
 
 ComponentDescriptor const &ComponentDescriptorRegistry::at(
     std::string const &componentName) const {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
 
   auto unifiedComponentName = componentNameByReactViewName(componentName);
 
@@ -95,7 +95,7 @@ ComponentDescriptor const &ComponentDescriptorRegistry::at(
 ComponentDescriptor const *ComponentDescriptorRegistry::
     findComponentDescriptorByHandle_DO_NOT_USE_THIS_IS_BROKEN(
         ComponentHandle componentHandle) const {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
 
   auto iterator = _registryByHandle.find(componentHandle);
   if (iterator == _registryByHandle.end()) {
@@ -107,14 +107,14 @@ ComponentDescriptor const *ComponentDescriptorRegistry::
 
 ComponentDescriptor const &ComponentDescriptorRegistry::at(
     ComponentHandle componentHandle) const {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
 
   return *_registryByHandle.at(componentHandle);
 }
 
 bool ComponentDescriptorRegistry::hasComponentDescriptorAt(
     ComponentHandle componentHandle) const {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
 
   auto iterator = _registryByHandle.find(componentHandle);
   if (iterator == _registryByHandle.end()) {

ReactCommon/react/renderer/componentregistry/ComponentDescriptorRegistry.h

@@ -9,8 +9,8 @@
 
 #include <memory>
 
-#include <better/map.h>
-#include <better/mutex.h>
+#include <butter/map.h>
+#include <butter/mutex.h>
 
 #include <react/renderer/componentregistry/ComponentDescriptorProvider.h>
 #include <react/renderer/core/ComponentDescriptor.h>
@@ -80,10 +80,10 @@ class ComponentDescriptorRegistry {
    */
   void add(ComponentDescriptorProvider componentDescriptorProvider) const;
 
-  mutable better::shared_mutex mutex_;
-  mutable better::map<ComponentHandle, SharedComponentDescriptor>
+  mutable butter::shared_mutex mutex_;
+  mutable butter::map<ComponentHandle, SharedComponentDescriptor>
       _registryByHandle;
-  mutable better::map<std::string, SharedComponentDescriptor> _registryByName;
+  mutable butter::map<std::string, SharedComponentDescriptor> _registryByName;
   ComponentDescriptor::Shared _fallbackComponentDescriptor;
   ComponentDescriptorParameters parameters_{};
   ComponentDescriptorProviderRegistry const &providerRegistry_;

ReactCommon/react/renderer/components/image/conversions.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/map.h>
+#include <butter/map.h>
 #include <folly/dynamic.h>
 #include <glog/logging.h>
 #include <react/debug/react_native_assert.h>
@@ -30,8 +30,8 @@ inline void fromRawValue(
     return;
   }
 
-  if (value.hasType<better::map<std::string, RawValue>>()) {
-    auto items = (better::map<std::string, RawValue>)value;
+  if (value.hasType<butter::map<std::string, RawValue>>()) {
+    auto items = (butter::map<std::string, RawValue>)value;
     result = {};
 
     result.type = ImageSource::Type::Remote;

ReactCommon/react/renderer/components/text/ParagraphShadowNode.h

@@ -101,7 +101,7 @@ class ParagraphShadowNode final : public ConcreteViewShadowNode<
   /*
    * Cached content of the subtree started from the node.
    */
-  mutable better::optional<Content> content_{};
+  mutable butter::optional<Content> content_{};
 };
 
 } // namespace react

ReactCommon/react/renderer/components/textinput/androidtextinput/react/renderer/components/androidtextinput/AndroidTextInputComponentDescriptor.h

@@ -180,7 +180,7 @@ class AndroidTextInputComponentDescriptor final
       "com/facebook/react/fabric/FabricUIManager";
 
   SharedTextLayoutManager textLayoutManager_;
-  mutable better::map<int, YGStyle::Edges> surfaceIdToThemePaddingMap_;
+  mutable butter::map<int, YGStyle::Edges> surfaceIdToThemePaddingMap_;
 };
 
 } // namespace react

ReactCommon/react/renderer/components/textinput/androidtextinput/react/renderer/components/androidtextinput/AndroidTextInputProps.h

@@ -37,7 +37,7 @@ static inline void fromRawValue(
     const PropsParserContext &context,
     const RawValue &value,
     AndroidTextInputSelectionStruct &result) {
-  auto map = (better::map<std::string, RawValue>)value;
+  auto map = (butter::map<std::string, RawValue>)value;
 
   auto start = map.find("start");
   if (start != map.end()) {
@@ -63,7 +63,7 @@ static inline void fromRawValue(
     const PropsParserContext &context,
     const RawValue &value,
     AndroidTextInputTextShadowOffsetStruct &result) {
-  auto map = (better::map<std::string, RawValue>)value;
+  auto map = (butter::map<std::string, RawValue>)value;
 
   auto width = map.find("width");
   if (width != map.end()) {

ReactCommon/react/renderer/components/textinput/androidtextinput/react/renderer/components/androidtextinput/AndroidTextInputShadowNode.h

@@ -81,7 +81,7 @@ class AndroidTextInputShadowNode final : public ConcreteViewShadowNode<
    * Cached attributed string that represents the content of the subtree started
    * from the node.
    */
-  mutable better::optional<AttributedString> cachedAttributedString_{};
+  mutable butter::optional<AttributedString> cachedAttributedString_{};
 };
 
 } // namespace react

ReactCommon/react/renderer/components/textinput/iostextinput/TextInputProps.cpp

@@ -87,7 +87,7 @@ TextInputProps::TextInputProps(
           rawProps,
           "selection",
           sourceProps.selection,
-          better::optional<Selection>())),
+          butter::optional<Selection>())),
       inputAccessoryViewID(convertRawProp(
           context,
           rawProps,

ReactCommon/react/renderer/components/textinput/iostextinput/TextInputProps.h

@@ -58,7 +58,7 @@ class TextInputProps final : public ViewProps, public BaseTextProps {
   int const mostRecentEventCount{0};
 
   bool autoFocus{false};
-  better::optional<Selection> selection{};
+  butter::optional<Selection> selection{};
 
   std::string const inputAccessoryViewID{};
 

ReactCommon/react/renderer/components/textinput/iostextinput/primitives.h

@@ -9,7 +9,7 @@
 
 #include <string>
 
-#include <better/optional.h>
+#include <butter/optional.h>
 
 namespace facebook {
 namespace react {
@@ -106,7 +106,7 @@ class TextInputTraits final {
    * iOS & Android
    * Default value: `empty` (`null`).
    */
-  better::optional<bool> autoCorrect{};
+  butter::optional<bool> autoCorrect{};
 
   /*
    * iOS & Android
@@ -141,7 +141,7 @@ class TextInputTraits final {
    * Can be empty (`null` in JavaScript) which means `default`.
    * Default value: `empty` (`null`).
    */
-  better::optional<bool> spellCheck{};
+  butter::optional<bool> spellCheck{};
 
   /*
    * iOS & Android

ReactCommon/react/renderer/components/textinput/iostextinput/propsConversions.h

@@ -149,8 +149,8 @@ inline void fromRawValue(
     const PropsParserContext &context,
     const RawValue &value,
     Selection &result) {
-  if (value.hasType<better::map<std::string, int>>()) {
-    auto map = (better::map<std::string, int>)value;
+  if (value.hasType<butter::map<std::string, int>>()) {
+    auto map = (butter::map<std::string, int>)value;
     for (const auto &pair : map) {
       if (pair.first == "start") {
         result.start = pair.second;

ReactCommon/react/renderer/components/view/AccessibilityPrimitives.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <cinttypes>
 #include <string>
 
@@ -50,7 +50,7 @@ constexpr enum AccessibilityTraits operator&(
 
 struct AccessibilityAction {
   std::string name{""};
-  better::optional<std::string> label{};
+  butter::optional<std::string> label{};
 };
 
 struct AccessibilityState {
@@ -76,10 +76,10 @@ constexpr bool operator!=(
 }
 
 struct AccessibilityValue {
-  better::optional<int> min;
-  better::optional<int> max;
-  better::optional<int> now;
-  better::optional<std::string> text{};
+  butter::optional<int> min;
+  butter::optional<int> max;
+  butter::optional<int> now;
+  butter::optional<std::string> text{};
 };
 
 constexpr bool operator==(

ReactCommon/react/renderer/components/view/ViewProps.h

@@ -54,7 +54,7 @@ class ViewProps : public YogaStylableProps, public AccessibilityProps {
   Transform transform{};
   BackfaceVisibility backfaceVisibility{};
   bool shouldRasterize{};
-  better::optional<int> zIndex{};
+  butter::optional<int> zIndex{};
 
   // Events
   PointerEventsMode pointerEvents{};

ReactCommon/react/renderer/components/view/YogaLayoutableShadowNode.h

@@ -25,7 +25,7 @@ namespace react {
 
 class YogaLayoutableShadowNode : public LayoutableShadowNode {
  public:
-  using UnsharedList = better::small_vector<
+  using UnsharedList = butter::small_vector<
       YogaLayoutableShadowNode *,
       kShadowNodeChildrenSmallVectorSize>;
 

ReactCommon/react/renderer/components/view/accessibilityPropsConversions.h

@@ -133,7 +133,7 @@ inline void fromRawValue(
     const PropsParserContext &context,
     const RawValue &value,
     AccessibilityState &result) {
-  auto map = (better::map<std::string, RawValue>)value;
+  auto map = (butter::map<std::string, RawValue>)value;
   auto selected = map.find("selected");
   if (selected != map.end()) {
     fromRawValue(context, selected->second, result.selected);
@@ -212,7 +212,7 @@ inline void fromRawValue(
     const PropsParserContext &context,
     const RawValue &value,
     AccessibilityAction &result) {
-  auto map = (better::map<std::string, RawValue>)value;
+  auto map = (butter::map<std::string, RawValue>)value;
 
   auto name = map.find("name");
   react_native_assert(name != map.end() && name->second.hasType<std::string>());
@@ -232,7 +232,7 @@ inline void fromRawValue(
     const PropsParserContext &,
     const RawValue &value,
     AccessibilityValue &result) {
-  auto map = (better::map<std::string, RawValue>)value;
+  auto map = (butter::map<std::string, RawValue>)value;
 
   auto min = map.find("min");
   if (min != map.end()) {

ReactCommon/react/renderer/components/view/conversions.h

@@ -7,8 +7,8 @@
 
 #pragma once
 
-#include <better/map.h>
-#include <better/optional.h>
+#include <butter/map.h>
+#include <butter/optional.h>
 #include <folly/Conv.h>
 #include <folly/dynamic.h>
 #include <glog/logging.h>
@@ -98,9 +98,9 @@ inline YGValue yogaStyleValueFromFloat(
   return {(float)value, unit};
 }
 
-inline better::optional<Float> optionalFloatFromYogaValue(
+inline butter::optional<Float> optionalFloatFromYogaValue(
     const YGValue value,
-    better::optional<Float> base = {}) {
+    butter::optional<Float> base = {}) {
   switch (value.unit) {
     case YGUnitUndefined:
       return {};
@@ -108,9 +108,9 @@ inline better::optional<Float> optionalFloatFromYogaValue(
       return floatFromYogaFloat(value.value);
     case YGUnitPercent:
       return base.has_value()
-          ? better::optional<Float>(
+          ? butter::optional<Float>(
                 base.value() * floatFromYogaFloat(value.value))
-          : better::optional<Float>();
+          : butter::optional<Float>();
     case YGUnitAuto:
       return {};
   }
@@ -444,14 +444,14 @@ inline void fromRawValue(
   auto configurations = static_cast<std::vector<RawValue>>(value);
 
   for (const auto &configuration : configurations) {
-    if (!configuration.hasType<better::map<std::string, RawValue>>()) {
+    if (!configuration.hasType<butter::map<std::string, RawValue>>()) {
       // TODO: The following checks have to be removed after codegen is shipped.
       // See T45151459.
       continue;
     }
 
     auto configurationPair =
-        static_cast<better::map<std::string, RawValue>>(configuration);
+        static_cast<butter::map<std::string, RawValue>>(configuration);
     auto pair = configurationPair.begin();
     auto operation = pair->first;
     auto &parameters = pair->second;

ReactCommon/react/renderer/components/view/primitives.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <react/renderer/graphics/Color.h>
 #include <react/renderer/graphics/Geometry.h>
 #include <array>
@@ -25,7 +25,7 @@ enum class BorderStyle { Solid, Dotted, Dashed };
 template <typename T>
 struct CascadedRectangleEdges {
   using Counterpart = RectangleEdges<T>;
-  using OptionalT = better::optional<T>;
+  using OptionalT = butter::optional<T>;
 
   OptionalT left{};
   OptionalT top{};
@@ -86,7 +86,7 @@ struct CascadedRectangleEdges {
 template <typename T>
 struct CascadedRectangleCorners {
   using Counterpart = RectangleCorners<T>;
-  using OptionalT = better::optional<T>;
+  using OptionalT = butter::optional<T>;
 
   OptionalT topLeft{};
   OptionalT topRight{};

ReactCommon/react/renderer/core/LayoutableShadowNode.cpp

@@ -56,7 +56,7 @@ LayoutMetrics LayoutableShadowNode::computeRelativeLayoutMetrics(
   // Step 1.
   // Creating a list of nodes that form a chain from the descender node to
   // ancestor node inclusively.
-  auto shadowNodeList = better::small_vector<ShadowNode const *, 16>{};
+  auto shadowNodeList = butter::small_vector<ShadowNode const *, 16>{};
 
   // Finding the measured node.
   // The last element in the `AncestorList` is a pair of a parent of the node

ReactCommon/react/renderer/core/LayoutableShadowNode.h

@@ -12,7 +12,7 @@
 #include <memory>
 #include <vector>
 
-#include <better/small_vector.h>
+#include <butter/small_vector.h>
 #include <react/debug/react_native_assert.h>
 #include <react/renderer/core/LayoutMetrics.h>
 #include <react/renderer/core/ShadowNode.h>
@@ -49,7 +49,7 @@ class LayoutableShadowNode : public ShadowNode {
     bool includeViewportOffset{false};
   };
 
-  using UnsharedList = better::
+  using UnsharedList = butter::
       small_vector<LayoutableShadowNode *, kShadowNodeChildrenSmallVectorSize>;
 
   /*

ReactCommon/react/renderer/core/RawProps.h

@@ -9,9 +9,9 @@
 
 #include <limits>
 
-#include <better/map.h>
-#include <better/optional.h>
-#include <better/small_vector.h>
+#include <butter/map.h>
+#include <butter/optional.h>
+#include <butter/small_vector.h>
 
 #include <folly/dynamic.h>
 #include <jsi/JSIDynamic.h>
@@ -125,10 +125,10 @@ class RawProps final {
    * Parsed artefacts:
    * To be used by `RawPropParser`.
    */
-  mutable better::
+  mutable butter::
       small_vector<RawPropsValueIndex, kNumberOfPropsPerComponentSoftCap>
           keyIndexToValueIndex_;
-  mutable better::
+  mutable butter::
       small_vector<RawValue, kNumberOfExplicitlySpecifedPropsSoftCap>
           values_;
 };

ReactCommon/react/renderer/core/RawPropsKeyMap.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/small_vector.h>
+#include <butter/small_vector.h>
 
 #include <react/renderer/core/RawPropsKey.h>
 #include <react/renderer/core/RawPropsPrimitives.h>
@@ -55,8 +55,8 @@ class RawPropsKeyMap final {
       Item const &rhs) noexcept;
   static bool hasSameName(Item const &lhs, Item const &rhs) noexcept;
 
-  better::small_vector<Item, kNumberOfExplicitlySpecifedPropsSoftCap> items_{};
-  better::small_vector<RawPropsPropNameLength, kPropNameLengthHardCap>
+  butter::small_vector<Item, kNumberOfExplicitlySpecifedPropsSoftCap> items_{};
+  butter::small_vector<RawPropsPropNameLength, kPropNameLengthHardCap>
       buckets_{};
 };
 

ReactCommon/react/renderer/core/RawPropsParser.h

@@ -7,8 +7,8 @@
 
 #pragma once
 
-#include <better/map.h>
-#include <better/small_vector.h>
+#include <butter/map.h>
+#include <butter/small_vector.h>
 #include <react/renderer/core/Props.h>
 #include <react/renderer/core/PropsParserContext.h>
 #include <react/renderer/core/RawProps.h>
@@ -76,7 +76,7 @@ class RawPropsParser final {
   RawValue const *at(RawProps const &rawProps, RawPropsKey const &key)
       const noexcept;
 
-  mutable better::small_vector<RawPropsKey, kNumberOfPropsPerComponentSoftCap>
+  mutable butter::small_vector<RawPropsKey, kNumberOfPropsPerComponentSoftCap>
       keys_{};
   mutable RawPropsKeyMap nameToIndex_{};
   mutable int size_{0};

ReactCommon/react/renderer/core/RawValue.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/map.h>
+#include <butter/map.h>
 #include <folly/dynamic.h>
 #include <jsi/JSIDynamic.h>
 #include <jsi/jsi.h>
@@ -78,7 +78,7 @@ class RawValue {
   /*
    * Copy constructor and copy assignment operator would be private and only for
    * internal use, but it's needed for user-code that does `auto val =
-   * (better::map<std::string, RawValue>)rawVal;`
+   * (butter::map<std::string, RawValue>)rawVal;`
    */
   RawValue(RawValue const &other) noexcept : dynamic_(other.dynamic_) {}
 
@@ -185,7 +185,7 @@ class RawValue {
   template <typename T>
   static bool checkValueType(
       const folly::dynamic &dynamic,
-      better::map<std::string, T> *type) noexcept {
+      butter::map<std::string, T> *type) noexcept {
     if (!dynamic.isObject()) {
       return false;
     }
@@ -267,11 +267,11 @@ class RawValue {
   }
 
   template <typename T>
-  static better::map<std::string, T> castValue(
+  static butter::map<std::string, T> castValue(
       const folly::dynamic &dynamic,
-      better::map<std::string, T> *type) noexcept {
+      butter::map<std::string, T> *type) noexcept {
     react_native_assert(dynamic.isObject());
-    auto result = better::map<std::string, T>{};
+    auto result = butter::map<std::string, T>{};
     for (const auto &item : dynamic.items()) {
       react_native_assert(item.first.isString());
       result[item.first.getString()] = castValue(item.second, (T *)nullptr);

ReactCommon/react/renderer/core/ShadowNode.cpp

@@ -9,7 +9,7 @@
 #include "DynamicPropsUtilities.h"
 #include "ShadowNodeFragment.h"
 
-#include <better/small_vector.h>
+#include <butter/small_vector.h>
 
 #include <react/debug/react_native_assert.h>
 #include <react/renderer/core/ComponentDescriptor.h>

ReactCommon/react/renderer/core/ShadowNode.h

@@ -11,7 +11,7 @@
 #include <string>
 #include <vector>
 
-#include <better/small_vector.h>
+#include <butter/small_vector.h>
 #include <react/renderer/core/EventEmitter.h>
 #include <react/renderer/core/Props.h>
 #include <react/renderer/core/ReactPrimitives.h>
@@ -34,7 +34,7 @@ class ShadowNode;
 using SharedShadowNode = std::shared_ptr<const ShadowNode>;
 using WeakShadowNode = std::weak_ptr<const ShadowNode>;
 using SharedShadowNodeList =
-    better::small_vector<SharedShadowNode, kShadowNodeChildrenSmallVectorSize>;
+    butter::small_vector<SharedShadowNode, kShadowNodeChildrenSmallVectorSize>;
 using SharedShadowNodeSharedList = std::shared_ptr<const SharedShadowNodeList>;
 using SharedShadowNodeUnsharedList = std::shared_ptr<SharedShadowNodeList>;
 
@@ -44,14 +44,14 @@ class ShadowNode : public Sealable, public DebugStringConvertible {
   using Weak = std::weak_ptr<ShadowNode const>;
   using Unshared = std::shared_ptr<ShadowNode>;
   using ListOfShared =
-      better::small_vector<Shared, kShadowNodeChildrenSmallVectorSize>;
+      butter::small_vector<Shared, kShadowNodeChildrenSmallVectorSize>;
   using ListOfWeak =
-      better::small_vector<Weak, kShadowNodeChildrenSmallVectorSize>;
+      butter::small_vector<Weak, kShadowNodeChildrenSmallVectorSize>;
   using SharedListOfShared = std::shared_ptr<ListOfShared const>;
   using UnsharedListOfShared = std::shared_ptr<ListOfShared>;
   using UnsharedListOfWeak = std::shared_ptr<ListOfWeak>;
 
-  using AncestorList = better::small_vector<
+  using AncestorList = butter::small_vector<
       std::pair<
           std::reference_wrapper<ShadowNode const> /* parentNode */,
           int /* childIndex */>,

ReactCommon/react/renderer/core/ShadowNodeFamily.cpp

@@ -57,7 +57,7 @@ const ComponentDescriptor &ShadowNodeFamily::getComponentDescriptor() const {
 
 AncestorList ShadowNodeFamily::getAncestors(
     ShadowNode const &ancestorShadowNode) const {
-  auto families = better::small_vector<ShadowNodeFamily const *, 64>{};
+  auto families = butter::small_vector<ShadowNodeFamily const *, 64>{};
   auto ancestorFamily = ancestorShadowNode.family_.get();
 
   auto family = this;
@@ -96,12 +96,12 @@ AncestorList ShadowNodeFamily::getAncestors(
 }
 
 State::Shared ShadowNodeFamily::getMostRecentState() const {
-  std::unique_lock<better::shared_mutex> lock(mutex_);
+  std::unique_lock<butter::shared_mutex> lock(mutex_);
   return mostRecentState_;
 }
 
 void ShadowNodeFamily::setMostRecentState(State::Shared const &state) const {
-  std::unique_lock<better::shared_mutex> lock(mutex_);
+  std::unique_lock<butter::shared_mutex> lock(mutex_);
 
   /*
    * Checking and setting `isObsolete_` prevents old states to be recommitted
@@ -122,7 +122,7 @@ void ShadowNodeFamily::setMostRecentState(State::Shared const &state) const {
 
 std::shared_ptr<State const> ShadowNodeFamily::getMostRecentStateIfObsolete(
     State const &state) const {
-  std::unique_lock<better::shared_mutex> lock(mutex_);
+  std::unique_lock<butter::shared_mutex> lock(mutex_);
   if (!state.isObsolete_) {
     return {};
   }

ReactCommon/react/renderer/core/ShadowNodeFamily.h

@@ -9,8 +9,8 @@
 
 #include <memory>
 
-#include <better/mutex.h>
-#include <better/small_vector.h>
+#include <butter/mutex.h>
+#include <butter/small_vector.h>
 
 #include <react/renderer/core/EventEmitter.h>
 #include <react/renderer/core/ReactPrimitives.h>
@@ -32,7 +32,7 @@ class ShadowNodeFamily final {
   using Shared = std::shared_ptr<ShadowNodeFamily const>;
   using Weak = std::weak_ptr<ShadowNodeFamily const>;
 
-  using AncestorList = better::small_vector<
+  using AncestorList = butter::small_vector<
       std::pair<
           std::reference_wrapper<ShadowNode const> /* parentNode */,
           int /* childIndex */>,
@@ -101,7 +101,7 @@ class ShadowNodeFamily final {
 
   EventDispatcher::Weak eventDispatcher_;
   mutable std::shared_ptr<State const> mostRecentState_;
-  mutable better::shared_mutex mutex_;
+  mutable butter::shared_mutex mutex_;
 
   /*
    * Deprecated.

ReactCommon/react/renderer/core/propsConversions.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <folly/Likely.h>
 #include <folly/dynamic.h>
 #include <react/renderer/core/PropsParserContext.h>
@@ -106,12 +106,12 @@ T convertRawProp(
 }
 
 template <typename T>
-static better::optional<T> convertRawProp(
+static butter::optional<T> convertRawProp(
     const PropsParserContext &context,
     RawProps const &rawProps,
     char const *name,
-    better::optional<T> const &sourceValue,
-    better::optional<T> const &defaultValue,
+    butter::optional<T> const &sourceValue,
+    butter::optional<T> const &defaultValue,
     char const *namePrefix = nullptr,
     char const *nameSuffix = nullptr) {
   const auto *rawValue = rawProps.at(name, namePrefix, nameSuffix);
@@ -128,7 +128,7 @@ static better::optional<T> convertRawProp(
 
   T result;
   fromRawValue(context, *rawValue, result);
-  return better::optional<T>{result};
+  return butter::optional<T>{result};
 }
 
 } // namespace react

ReactCommon/react/renderer/debug/BUCK

@@ -50,7 +50,7 @@ rn_xplat_cxx_library(
         "//xplat/folly:headers_only",
         "//xplat/folly:memory",
         "//xplat/folly:molly",
-        react_native_xplat_target("better:better"),
+        react_native_xplat_target("butter:butter"),
         react_native_xplat_target("react/debug:debug"),
     ],
 )

ReactCommon/react/renderer/debug/debugStringConvertibleUtils.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <limits>
 #include <memory>
 #include <string>
@@ -34,7 +34,7 @@ debugStringConvertibleItem(std::string name, T value, T defaultValue = {}) {
 template <typename T>
 inline SharedDebugStringConvertible debugStringConvertibleItem(
     std::string name,
-    better::optional<T> value,
+    butter::optional<T> value,
     T defaultValue = {}) {
   if (!value.hasValue()) {
     return nullptr;

ReactCommon/react/renderer/graphics/BUCK

@@ -102,7 +102,7 @@ rn_xplat_cxx_library(
     visibility = ["PUBLIC"],
     deps = [
         react_native_xplat_target("react/debug:debug"),
-        react_native_xplat_target("better:better"),
+        react_native_xplat_target("butter:butter"),
         "//third-party/glog:glog",
         "//xplat/fbsystrace:fbsystrace",
         "//xplat/folly:headers_only",

ReactCommon/react/renderer/graphics/conversions.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/map.h>
+#include <butter/map.h>
 #include <glog/logging.h>
 #include <react/debug/react_native_assert.h>
 #include <react/renderer/core/PropsParserContext.h>
@@ -88,8 +88,8 @@ inline void fromRawValue(
     const PropsParserContext &context,
     const RawValue &value,
     Point &result) {
-  if (value.hasType<better::map<std::string, Float>>()) {
-    auto map = (better::map<std::string, Float>)value;
+  if (value.hasType<butter::map<std::string, Float>>()) {
+    auto map = (butter::map<std::string, Float>)value;
     for (const auto &pair : map) {
       if (pair.first == "x") {
         result.x = pair.second;
@@ -119,8 +119,8 @@ inline void fromRawValue(
     const PropsParserContext &context,
     const RawValue &value,
     Size &result) {
-  if (value.hasType<better::map<std::string, Float>>()) {
-    auto map = (better::map<std::string, Float>)value;
+  if (value.hasType<butter::map<std::string, Float>>()) {
+    auto map = (butter::map<std::string, Float>)value;
     for (const auto &pair : map) {
       if (pair.first == "width") {
         result.width = pair.second;
@@ -159,8 +159,8 @@ inline void fromRawValue(
     return;
   }
 
-  if (value.hasType<better::map<std::string, Float>>()) {
-    auto map = (better::map<std::string, Float>)value;
+  if (value.hasType<butter::map<std::string, Float>>()) {
+    auto map = (butter::map<std::string, Float>)value;
     for (const auto &pair : map) {
       if (pair.first == "top") {
         result.top = pair.second;
@@ -203,8 +203,8 @@ inline void fromRawValue(
     return;
   }
 
-  if (value.hasType<better::map<std::string, Float>>()) {
-    auto map = (better::map<std::string, Float>)value;
+  if (value.hasType<butter::map<std::string, Float>>()) {
+    auto map = (butter::map<std::string, Float>)value;
     for (const auto &pair : map) {
       if (pair.first == "topLeft") {
         result.topLeft = pair.second;

ReactCommon/react/renderer/graphics/platform/android/react/renderer/graphics/PlatformColorParser.h

@@ -21,8 +21,8 @@ inline ColorComponents parsePlatformColor(
     const RawValue &value) {
   ColorComponents colorComponents = {0, 0, 0, 0};
 
-  if (value.hasType<better::map<std::string, std::vector<std::string>>>()) {
-    auto map = (better::map<std::string, std::vector<std::string>>)value;
+  if (value.hasType<butter::map<std::string, std::vector<std::string>>>()) {
+    auto map = (butter::map<std::string, std::vector<std::string>>)value;
     auto resourcePaths = map["resource_paths"];
     auto dynamicResourcePaths = folly::dynamic::array();
     for (const auto &resourcePath : resourcePaths) {

ReactCommon/react/renderer/graphics/platform/ios/Color.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <cmath>
 
 #include <folly/Hash.h>

ReactCommon/react/renderer/graphics/platform/ios/PlatformColorParser.h

@@ -18,8 +18,8 @@ namespace react {
 inline ColorComponents parsePlatformColor(
     const PropsParserContext &context,
     const RawValue &value) {
-  if (value.hasType<better::map<std::string, RawValue>>()) {
-    auto items = (better::map<std::string, RawValue>)value;
+  if (value.hasType<butter::map<std::string, RawValue>>()) {
+    auto items = (butter::map<std::string, RawValue>)value;
     if (items.find("semantic") != items.end() &&
         items.at("semantic").hasType<std::vector<std::string>>()) {
       auto semanticItems = (std::vector<std::string>)items.at("semantic");

ReactCommon/react/renderer/imagemanager/ImageResponseObserverCoordinator.h

@@ -10,7 +10,7 @@
 #include <react/renderer/imagemanager/ImageResponse.h>
 #include <react/renderer/imagemanager/ImageResponseObserver.h>
 
-#include <better/small_vector.h>
+#include <butter/small_vector.h>
 #include <mutex>
 #include <vector>
 
@@ -59,7 +59,7 @@ class ImageResponseObserverCoordinator {
    * List of observers.
    * Mutable: protected by mutex_.
    */
-  mutable better::small_vector<ImageResponseObserver const *, 1> observers_;
+  mutable butter::small_vector<ImageResponseObserver const *, 1> observers_;
 
   /*
    * Current status of image loading.

ReactCommon/react/renderer/mounting/Android.mk

@@ -23,7 +23,7 @@ LOCAL_STATIC_LIBRARIES :=
 
 LOCAL_SHARED_LIBRARIES := \
   glog \
-  libbetter \
+  libbutter \
   libfolly_futures \
   libfolly_json \
   libglog_init \
@@ -40,7 +40,7 @@ LOCAL_SHARED_LIBRARIES := \
 
 include $(BUILD_SHARED_LIBRARY)
 
-$(call import-module,better)
+$(call import-module,butter)
 $(call import-module,glog)
 $(call import-module,folly)
 $(call import-module,fbgloginit)

ReactCommon/react/renderer/mounting/BUCK

@@ -50,7 +50,7 @@ rn_xplat_cxx_library(
         "//xplat/folly:headers_only",
         "//xplat/folly:memory",
         "//xplat/folly:molly",
-        react_native_xplat_target("better:better"),
+        react_native_xplat_target("butter:butter"),
         react_native_xplat_target("react/debug:debug"),
         react_native_xplat_target("react/renderer/components/root:root"),
         react_native_xplat_target("react/renderer/components/view:view"),

ReactCommon/react/renderer/mounting/Differentiator.cpp

@@ -7,8 +7,8 @@
 
 #include "Differentiator.h"
 
-#include <better/map.h>
-#include <better/small_vector.h>
+#include <butter/map.h>
+#include <butter/small_vector.h>
 #include <react/debug/react_native_assert.h>
 #include <react/renderer/core/LayoutableShadowNode.h>
 #include <react/renderer/debug/SystraceSection.h>
@@ -168,7 +168,7 @@ class TinyMap final {
     erasedAtFront_ = 0;
   }
 
-  better::small_vector<Pair, DefaultSize> vector_;
+  butter::small_vector<Pair, DefaultSize> vector_;
   size_t numErased_{0};
   size_t erasedAtFront_{0};
 };

ReactCommon/react/renderer/mounting/MountingCoordinator.cpp

@@ -75,11 +75,11 @@ void MountingCoordinator::resetLatestRevision() const {
   lastRevision_.reset();
 }
 
-better::optional<MountingTransaction> MountingCoordinator::pullTransaction()
+butter::optional<MountingTransaction> MountingCoordinator::pullTransaction()
     const {
   std::lock_guard<std::mutex> lock(mutex_);
 
-  auto transaction = better::optional<MountingTransaction>{};
+  auto transaction = butter::optional<MountingTransaction>{};
 
   // Base case
   if (lastRevision_.has_value()) {

ReactCommon/react/renderer/mounting/MountingCoordinator.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <chrono>
 
 #include <react/renderer/debug/flags.h>
@@ -56,7 +56,7 @@ class MountingCoordinator final {
    * However, a consumer should always call it on the same thread (e.g. on the
    * main thread) or ensure sequentiality of mount transactions separately.
    */
-  better::optional<MountingTransaction> pullTransaction() const;
+  butter::optional<MountingTransaction> pullTransaction() const;
 
   /*
    * Blocks the current thread until a new mounting transaction is available or
@@ -104,7 +104,7 @@ class MountingCoordinator final {
 
   mutable std::mutex mutex_;
   mutable ShadowTreeRevision baseRevision_;
-  mutable better::optional<ShadowTreeRevision> lastRevision_{};
+  mutable butter::optional<ShadowTreeRevision> lastRevision_{};
   mutable MountingTransaction::Number number_{0};
   mutable std::condition_variable signal_;
   mutable std::weak_ptr<MountingOverrideDelegate const>

ReactCommon/react/renderer/mounting/MountingOverrideDelegate.h

@@ -36,7 +36,7 @@ class MountingOverrideDelegate {
    * @param mountingCoordinator
    * @return
    */
-  virtual better::optional<MountingTransaction> pullTransaction(
+  virtual butter::optional<MountingTransaction> pullTransaction(
       SurfaceId surfaceId,
       MountingTransaction::Number number,
       TransactionTelemetry const &telemetry,

ReactCommon/react/renderer/mounting/ShadowTree.cpp

@@ -270,7 +270,7 @@ void ShadowTree::setCommitMode(CommitMode commitMode) const {
   auto revision = ShadowTreeRevision{};
 
   {
-    std::unique_lock<better::shared_mutex> lock(commitMutex_);
+    std::unique_lock<butter::shared_mutex> lock(commitMutex_);
     if (commitMode_ == commitMode) {
       return;
     }
@@ -287,7 +287,7 @@ void ShadowTree::setCommitMode(CommitMode commitMode) const {
 }
 
 CommitMode ShadowTree::getCommitMode() const {
-  std::shared_lock<better::shared_mutex> lock(commitMutex_);
+  std::shared_lock<butter::shared_mutex> lock(commitMutex_);
   return commitMode_;
 }
 
@@ -330,7 +330,7 @@ CommitStatus ShadowTree::tryCommit(
 
   {
     // Reading `currentRevision_` in shared manner.
-    std::shared_lock<better::shared_mutex> lock(commitMutex_);
+    std::shared_lock<butter::shared_mutex> lock(commitMutex_);
     commitMode = commitMode_;
     oldRevision = currentRevision_;
   }
@@ -367,7 +367,7 @@ CommitStatus ShadowTree::tryCommit(
 
   {
     // Updating `currentRevision_` in unique manner if it hasn't changed.
-    std::unique_lock<better::shared_mutex> lock(commitMutex_);
+    std::unique_lock<butter::shared_mutex> lock(commitMutex_);
 
     if (currentRevision_.number != oldRevision.number) {
       return CommitStatus::Failed;
@@ -410,7 +410,7 @@ CommitStatus ShadowTree::tryCommit(
 }
 
 ShadowTreeRevision ShadowTree::getCurrentRevision() const {
-  std::shared_lock<better::shared_mutex> lock(commitMutex_);
+  std::shared_lock<butter::shared_mutex> lock(commitMutex_);
   return currentRevision_;
 }
 

ReactCommon/react/renderer/mounting/ShadowTree.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/mutex.h>
+#include <butter/mutex.h>
 #include <memory>
 
 #include <react/renderer/components/root/RootComponentDescriptor.h>
@@ -135,7 +135,7 @@ class ShadowTree final {
 
   SurfaceId const surfaceId_;
   ShadowTreeDelegate const &delegate_;
-  mutable better::shared_mutex commitMutex_;
+  mutable butter::shared_mutex commitMutex_;
   mutable CommitMode commitMode_{
       CommitMode::Normal}; // Protected by `commitMutex_`.
   mutable ShadowTreeRevision currentRevision_; // Protected by `commitMutex_`.

ReactCommon/react/renderer/mounting/ShadowTreeRegistry.cpp

@@ -18,14 +18,14 @@ ShadowTreeRegistry::~ShadowTreeRegistry() {
 }
 
 void ShadowTreeRegistry::add(std::unique_ptr<ShadowTree> &&shadowTree) const {
-  std::unique_lock<better::shared_mutex> lock(mutex_);
+  std::unique_lock<butter::shared_mutex> lock(mutex_);
 
   registry_.emplace(shadowTree->getSurfaceId(), std::move(shadowTree));
 }
 
 std::unique_ptr<ShadowTree> ShadowTreeRegistry::remove(
     SurfaceId surfaceId) const {
-  std::unique_lock<better::shared_mutex> lock(mutex_);
+  std::unique_lock<butter::shared_mutex> lock(mutex_);
 
   auto iterator = registry_.find(surfaceId);
   if (iterator == registry_.end()) {
@@ -40,7 +40,7 @@ std::unique_ptr<ShadowTree> ShadowTreeRegistry::remove(
 bool ShadowTreeRegistry::visit(
     SurfaceId surfaceId,
     std::function<void(const ShadowTree &shadowTree)> callback) const {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
 
   auto iterator = registry_.find(surfaceId);
 
@@ -54,7 +54,7 @@ bool ShadowTreeRegistry::visit(
 
 void ShadowTreeRegistry::enumerate(
     std::function<void(const ShadowTree &shadowTree)> callback) const {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
   for (auto const &pair : registry_) {
     callback(*pair.second);
   }

ReactCommon/react/renderer/mounting/ShadowTreeRegistry.h

@@ -7,8 +7,8 @@
 
 #pragma once
 
-#include <better/map.h>
-#include <better/mutex.h>
+#include <butter/map.h>
+#include <butter/mutex.h>
 
 #include <react/renderer/core/ReactPrimitives.h>
 #include <react/renderer/mounting/ShadowTree.h>
@@ -60,8 +60,8 @@ class ShadowTreeRegistry final {
       std::function<void(const ShadowTree &shadowTree)> callback) const;
 
  private:
-  mutable better::shared_mutex mutex_;
-  mutable better::map<SurfaceId, std::unique_ptr<ShadowTree>>
+  mutable butter::shared_mutex mutex_;
+  mutable butter::map<SurfaceId, std::unique_ptr<ShadowTree>>
       registry_; // Protected by `mutex_`.
 };
 

ReactCommon/react/renderer/mounting/ShadowTreeRevision.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/optional.h>
+#include <butter/optional.h>
 
 #include <react/renderer/components/root/RootShadowNode.h>
 #include <react/renderer/mounting/MountingOverrideDelegate.h>

ReactCommon/react/renderer/mounting/ShadowView.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/small_vector.h>
+#include <butter/small_vector.h>
 #include <folly/Hash.h>
 #include <react/renderer/core/EventEmitter.h>
 #include <react/renderer/core/LayoutMetrics.h>
@@ -65,9 +65,9 @@ std::vector<DebugStringConvertibleObject> getDebugProps(
  *
  */
 struct ShadowViewNodePair final {
-  using NonOwningList = better::
+  using NonOwningList = butter::
       small_vector<ShadowViewNodePair *, kShadowNodeChildrenSmallVectorSize>;
-  using OwningList = better::
+  using OwningList = butter::
       small_vector<ShadowViewNodePair, kShadowNodeChildrenSmallVectorSize>;
 
   ShadowView shadowView;
@@ -103,7 +103,7 @@ struct ShadowViewNodePair final {
  *
  */
 struct ShadowViewNodePairLegacy final {
-  using OwningList = better::small_vector<
+  using OwningList = butter::small_vector<
       ShadowViewNodePairLegacy,
       kShadowNodeChildrenSmallVectorSize>;
 

ReactCommon/react/renderer/runtimescheduler/BUCK

@@ -46,7 +46,7 @@ rn_xplat_cxx_library(
     deps = [
         react_native_xplat_target("runtimeexecutor:runtimeexecutor"),
         react_native_xplat_target("react/renderer/debug:debug"),
-        react_native_xplat_target("better:better"),
+        react_native_xplat_target("butter:butter"),
         react_native_xplat_target("callinvoker:callinvoker"),
     ],
 )

ReactCommon/react/renderer/runtimescheduler/Task.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/optional.h>
+#include <butter/optional.h>
 #include <jsi/jsi.h>
 #include <react/renderer/runtimescheduler/RuntimeSchedulerClock.h>
 #include <react/renderer/runtimescheduler/SchedulerPriority.h>
@@ -29,7 +29,7 @@ struct Task final {
   friend TaskPriorityComparer;
 
   SchedulerPriority priority;
-  better::optional<jsi::Function> callback;
+  butter::optional<jsi::Function> callback;
   RuntimeSchedulerClock::time_point expirationTime;
 
   jsi::Value execute(jsi::Runtime &runtime);

ReactCommon/react/renderer/scheduler/Scheduler.cpp

@@ -43,7 +43,7 @@ Scheduler::Scheduler(
 
   // Creating a container for future `EventDispatcher` instance.
   eventDispatcher_ =
-      std::make_shared<better::optional<EventDispatcher const>>();
+      std::make_shared<butter::optional<EventDispatcher const>>();
 
   auto uiManager = std::make_shared<UIManager>(
       runtimeExecutor_, schedulerToolbox.backgroundExecutor, contextContainer_);

ReactCommon/react/renderer/scheduler/Scheduler.h

@@ -125,7 +125,7 @@ class Scheduler final : public UIManagerDelegate {
    * parts that need to have ownership (and only ownership) of that, and then
    * fill the optional.
    */
-  std::shared_ptr<better::optional<EventDispatcher const>> eventDispatcher_;
+  std::shared_ptr<butter::optional<EventDispatcher const>> eventDispatcher_;
 
   /**
    * Hold onto ContextContainer. See SchedulerToolbox.

ReactCommon/react/renderer/scheduler/SurfaceHandler.cpp

@@ -29,12 +29,12 @@ SurfaceHandler::SurfaceHandler(SurfaceHandler &&other) noexcept {
 }
 
 SurfaceHandler &SurfaceHandler::operator=(SurfaceHandler &&other) noexcept {
-  std::unique_lock<better::shared_mutex> lock1(linkMutex_, std::defer_lock);
-  std::unique_lock<better::shared_mutex> lock2(
+  std::unique_lock<butter::shared_mutex> lock1(linkMutex_, std::defer_lock);
+  std::unique_lock<butter::shared_mutex> lock2(
       parametersMutex_, std::defer_lock);
-  std::unique_lock<better::shared_mutex> lock3(
+  std::unique_lock<butter::shared_mutex> lock3(
       other.linkMutex_, std::defer_lock);
-  std::unique_lock<better::shared_mutex> lock4(
+  std::unique_lock<butter::shared_mutex> lock4(
       other.parametersMutex_, std::defer_lock);
   std::lock(lock1, lock2, lock3, lock4);
 
@@ -55,13 +55,13 @@ void SurfaceHandler::setContextContainer(
 }
 
 Status SurfaceHandler::getStatus() const noexcept {
-  std::shared_lock<better::shared_mutex> lock(linkMutex_);
+  std::shared_lock<butter::shared_mutex> lock(linkMutex_);
   return link_.status;
 }
 
 void SurfaceHandler::start() const noexcept {
   SystraceSection s("SurfaceHandler::start");
-  std::unique_lock<better::shared_mutex> lock(linkMutex_);
+  std::unique_lock<butter::shared_mutex> lock(linkMutex_);
   react_native_assert(
       link_.status == Status::Registered && "Surface must be registered.");
   react_native_assert(
@@ -73,7 +73,7 @@ void SurfaceHandler::start() const noexcept {
   auto parameters = Parameters{};
   {
     SystraceSection s2("SurfaceHandler::start::paramsLock");
-    std::shared_lock<better::shared_mutex> parametersLock(parametersMutex_);
+    std::shared_lock<butter::shared_mutex> parametersLock(parametersMutex_);
     parameters = parameters_;
   }
 
@@ -100,7 +100,7 @@ void SurfaceHandler::start() const noexcept {
 void SurfaceHandler::stop() const noexcept {
   auto shadowTree = ShadowTree::Unique{};
   {
-    std::unique_lock<better::shared_mutex> lock(linkMutex_);
+    std::unique_lock<butter::shared_mutex> lock(linkMutex_);
     react_native_assert(
         link_.status == Status::Running && "Surface must be running.");
 
@@ -118,7 +118,7 @@ void SurfaceHandler::stop() const noexcept {
 
 void SurfaceHandler::setDisplayMode(DisplayMode displayMode) const noexcept {
   {
-    std::unique_lock<better::shared_mutex> lock(parametersMutex_);
+    std::unique_lock<butter::shared_mutex> lock(parametersMutex_);
     if (parameters_.displayMode == displayMode) {
       return;
     }
@@ -127,7 +127,7 @@ void SurfaceHandler::setDisplayMode(DisplayMode displayMode) const noexcept {
   }
 
   {
-    std::shared_lock<better::shared_mutex> lock(linkMutex_);
+    std::shared_lock<butter::shared_mutex> lock(linkMutex_);
 
     if (link_.status != Status::Running) {
       return;
@@ -144,41 +144,41 @@ void SurfaceHandler::setDisplayMode(DisplayMode displayMode) const noexcept {
 }
 
 DisplayMode SurfaceHandler::getDisplayMode() const noexcept {
-  std::shared_lock<better::shared_mutex> lock(parametersMutex_);
+  std::shared_lock<butter::shared_mutex> lock(parametersMutex_);
   return parameters_.displayMode;
 }
 
 #pragma mark - Accessors
 
 SurfaceId SurfaceHandler::getSurfaceId() const noexcept {
-  std::shared_lock<better::shared_mutex> lock(parametersMutex_);
+  std::shared_lock<butter::shared_mutex> lock(parametersMutex_);
   return parameters_.surfaceId;
 }
 
 void SurfaceHandler::setSurfaceId(SurfaceId surfaceId) const noexcept {
-  std::unique_lock<better::shared_mutex> lock(parametersMutex_);
+  std::unique_lock<butter::shared_mutex> lock(parametersMutex_);
   parameters_.surfaceId = surfaceId;
 }
 
 std::string SurfaceHandler::getModuleName() const noexcept {
-  std::shared_lock<better::shared_mutex> lock(parametersMutex_);
+  std::shared_lock<butter::shared_mutex> lock(parametersMutex_);
   return parameters_.moduleName;
 }
 
 void SurfaceHandler::setProps(folly::dynamic const &props) const noexcept {
   SystraceSection s("SurfaceHandler::setProps");
-  std::unique_lock<better::shared_mutex> lock(parametersMutex_);
+  std::unique_lock<butter::shared_mutex> lock(parametersMutex_);
   parameters_.props = props;
 }
 
 folly::dynamic SurfaceHandler::getProps() const noexcept {
-  std::shared_lock<better::shared_mutex> lock(parametersMutex_);
+  std::shared_lock<butter::shared_mutex> lock(parametersMutex_);
   return parameters_.props;
 }
 
 std::shared_ptr<MountingCoordinator const>
 SurfaceHandler::getMountingCoordinator() const noexcept {
-  std::shared_lock<better::shared_mutex> lock(linkMutex_);
+  std::shared_lock<butter::shared_mutex> lock(linkMutex_);
   react_native_assert(
       link_.status != Status::Unregistered && "Surface must be registered.");
   react_native_assert(
@@ -191,7 +191,7 @@ SurfaceHandler::getMountingCoordinator() const noexcept {
 Size SurfaceHandler::measure(
     LayoutConstraints const &layoutConstraints,
     LayoutContext const &layoutContext) const noexcept {
-  std::shared_lock<better::shared_mutex> lock(linkMutex_);
+  std::shared_lock<butter::shared_mutex> lock(linkMutex_);
 
   if (link_.status != Status::Running) {
     return layoutConstraints.clamp({0, 0});
@@ -217,7 +217,7 @@ void SurfaceHandler::constraintLayout(
     LayoutContext const &layoutContext) const noexcept {
   SystraceSection s("SurfaceHandler::constraintLayout");
   {
-    std::unique_lock<better::shared_mutex> lock(parametersMutex_);
+    std::unique_lock<butter::shared_mutex> lock(parametersMutex_);
 
     if (parameters_.layoutConstraints == layoutConstraints &&
         parameters_.layoutContext == layoutContext) {
@@ -229,7 +229,7 @@ void SurfaceHandler::constraintLayout(
   }
 
   {
-    std::shared_lock<better::shared_mutex> lock(linkMutex_);
+    std::shared_lock<butter::shared_mutex> lock(linkMutex_);
 
     if (link_.status != Status::Running) {
       return;
@@ -248,12 +248,12 @@ void SurfaceHandler::constraintLayout(
 }
 
 LayoutConstraints SurfaceHandler::getLayoutConstraints() const noexcept {
-  std::shared_lock<better::shared_mutex> lock(parametersMutex_);
+  std::shared_lock<butter::shared_mutex> lock(parametersMutex_);
   return parameters_.layoutConstraints;
 }
 
 LayoutContext SurfaceHandler::getLayoutContext() const noexcept {
-  std::shared_lock<better::shared_mutex> lock(parametersMutex_);
+  std::shared_lock<butter::shared_mutex> lock(parametersMutex_);
   return parameters_.layoutContext;
 }
 
@@ -292,7 +292,7 @@ void SurfaceHandler::applyDisplayMode(DisplayMode displayMode) const noexcept {
 }
 
 void SurfaceHandler::setUIManager(UIManager const *uiManager) const noexcept {
-  std::unique_lock<better::shared_mutex> lock(linkMutex_);
+  std::unique_lock<butter::shared_mutex> lock(linkMutex_);
 
   react_native_assert(
       link_.status != Status::Running && "Surface must not be running.");

ReactCommon/react/renderer/scheduler/SurfaceHandler.h

@@ -195,13 +195,13 @@ class SurfaceHandler {
   /*
    * `link_` and `linkMutex_` pair.
    */
-  mutable better::shared_mutex linkMutex_;
+  mutable butter::shared_mutex linkMutex_;
   mutable Link link_;
 
   /*
    * `parameters_` and `parametersMutex_` pair.
    */
-  mutable better::shared_mutex parametersMutex_;
+  mutable butter::shared_mutex parametersMutex_;
   mutable Parameters parameters_;
 };
 

ReactCommon/react/renderer/scheduler/SurfaceManager.cpp

@@ -22,7 +22,7 @@ void SurfaceManager::startSurface(
     LayoutConstraints const &layoutConstraints,
     LayoutContext const &layoutContext) const noexcept {
   {
-    std::unique_lock<better::shared_mutex> lock(mutex_);
+    std::unique_lock<butter::shared_mutex> lock(mutex_);
     auto surfaceHandler = SurfaceHandler{moduleName, surfaceId};
     surfaceHandler.setContextContainer(scheduler_.getContextContainer());
     registry_.emplace(surfaceId, std::move(surfaceHandler));
@@ -45,7 +45,7 @@ void SurfaceManager::stopSurface(SurfaceId surfaceId) const noexcept {
   });
 
   {
-    std::unique_lock<better::shared_mutex> lock(mutex_);
+    std::unique_lock<butter::shared_mutex> lock(mutex_);
 
     auto iterator = registry_.find(surfaceId);
     registry_.erase(iterator);
@@ -89,7 +89,7 @@ void SurfaceManager::visit(
     SurfaceId surfaceId,
     std::function<void(SurfaceHandler const &surfaceHandler)> const &callback)
     const noexcept {
-  std::shared_lock<better::shared_mutex> lock(mutex_);
+  std::shared_lock<butter::shared_mutex> lock(mutex_);
 
   auto iterator = registry_.find(surfaceId);
 

ReactCommon/react/renderer/scheduler/SurfaceManager.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/map.h>
+#include <butter/map.h>
 #include <mutex>
 
 #include <react/renderer/core/LayoutConstraints.h>
@@ -59,8 +59,8 @@ class SurfaceManager final {
       const noexcept;
 
   Scheduler const &scheduler_;
-  mutable better::shared_mutex mutex_; // Protects `registry_`.
-  mutable better::map<SurfaceId, SurfaceHandler> registry_{};
+  mutable butter::shared_mutex mutex_; // Protects `registry_`.
+  mutable butter::map<SurfaceId, SurfaceHandler> registry_{};
 };
 
 } // namespace react

ReactCommon/react/renderer/telemetry/Android.mk

@@ -23,7 +23,7 @@ LOCAL_STATIC_LIBRARIES :=
 
 LOCAL_SHARED_LIBRARIES := \
   glog \
-  libbetter \
+  libbutter \
   libfolly_futures \
   libfolly_json \
   libglog_init \
@@ -37,7 +37,7 @@ LOCAL_SHARED_LIBRARIES := \
 
 include $(BUILD_SHARED_LIBRARY)
 
-$(call import-module,better)
+$(call import-module,butter)
 $(call import-module,glog)
 $(call import-module,folly)
 $(call import-module,react/utils)

ReactCommon/react/renderer/telemetry/BUCK

@@ -50,7 +50,7 @@ rn_xplat_cxx_library(
         "//xplat/folly:headers_only",
         "//xplat/folly:memory",
         "//xplat/folly:molly",
-        react_native_xplat_target("better:better"),
+        react_native_xplat_target("butter:butter"),
         react_native_xplat_target("react/debug:debug"),
         react_native_xplat_target("react/utils:utils"),
     ],

ReactCommon/react/renderer/telemetry/SurfaceTelemetry.h

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include <better/small_vector.h>
+#include <butter/small_vector.h>
 #include <vector>
 
 #include <react/renderer/telemetry/TransactionTelemetry.h>
@@ -60,7 +60,7 @@ class SurfaceTelemetry final {
   int numberOfTextMeasurements_{};
   int lastRevisionNumber_{};
 
-  better::
+  butter::
       small_vector<TransactionTelemetry, kMaxNumberOfRecordedCommitTelemetries>
           recentTransactionTelemetries_{};
 };

ReactCommon/react/renderer/timeline/Timeline.h

@@ -10,7 +10,7 @@
 #include <memory>
 #include <vector>
 
-#include <better/mutex.h>
+#include <butter/mutex.h>
 
 #include <react/renderer/core/ReactPrimitives.h>
 #include <react/renderer/timeline/TimelineSnapshot.h>

ReactCommon/react/renderer/timeline/TimelineController.cpp

@@ -25,7 +25,7 @@ TimelineHandler TimelineController::enable(SurfaceId surfaceId) const {
   assert(shadowTreePtr);
 
   {
-    std::unique_lock<better::shared_mutex> lock(timelinesMutex_);
+    std::unique_lock<butter::shared_mutex> lock(timelinesMutex_);
 
     auto timeline = std::make_unique<Timeline>(*shadowTreePtr);
     auto handler = TimelineHandler{*timeline};
@@ -35,7 +35,7 @@ TimelineHandler TimelineController::enable(SurfaceId surfaceId) const {
 }
 
 void TimelineController::disable(TimelineHandler &&handler) const {
-  std::unique_lock<better::shared_mutex> lock(timelinesMutex_);
+  std::unique_lock<butter::shared_mutex> lock(timelinesMutex_);
 
   auto iterator = timelines_.find(handler.getSurfaceId());
   assert(iterator != timelines_.end());
@@ -57,7 +57,7 @@ RootShadowNode::Unshared TimelineController::shadowTreeWillCommit(
     ShadowTree const &shadowTree,
     RootShadowNode::Shared const &oldRootShadowNode,
     RootShadowNode::Unshared const &newRootShadowNode) const noexcept {
-  std::shared_lock<better::shared_mutex> lock(timelinesMutex_);
+  std::shared_lock<butter::shared_mutex> lock(timelinesMutex_);
 
   assert(uiManager_ && "`uiManager_` must not be `nullptr`.");
 

ReactCommon/react/renderer/timeline/TimelineController.h

@@ -9,7 +9,7 @@
 
 #include <memory>
 
-#include <better/map.h>
+#include <butter/map.h>
 
 #include <react/renderer/core/ReactPrimitives.h>
 #include <react/renderer/timeline/Timeline.h>
@@ -65,12 +65,12 @@ class TimelineController final : public UIManagerCommitHook {
   /*
    * Protects all the data members.
    */
-  mutable better::shared_mutex timelinesMutex_;
+  mutable butter::shared_mutex timelinesMutex_;
 
   /*
    * Owning collection of all running `Timeline` instances.
    */
-  mutable better::map<SurfaceId, std::unique_ptr<Timeline>> timelines_;
+  mutable butter::map<SurfaceId, std::unique_ptr<Timeline>> timelines_;
 
   mutable UIManager const *uiManager_;
   mutable SurfaceId lastUpdatedSurface_;

ReactCommon/react/renderer/uimanager/UIManager.cpp

@@ -376,7 +376,7 @@ ShadowTreeRegistry const &UIManager::getShadowTreeRegistry() const {
 
 void UIManager::registerCommitHook(
     UIManagerCommitHook const &commitHook) const {
-  std::unique_lock<better::shared_mutex> lock(commitHookMutex_);
+  std::unique_lock<butter::shared_mutex> lock(commitHookMutex_);
   react_native_assert(
       std::find(commitHooks_.begin(), commitHooks_.end(), &commitHook) ==
       commitHooks_.end());
@@ -386,7 +386,7 @@ void UIManager::registerCommitHook(
 
 void UIManager::unregisterCommitHook(
     UIManagerCommitHook const &commitHook) const {
-  std::unique_lock<better::shared_mutex> lock(commitHookMutex_);
+  std::unique_lock<butter::shared_mutex> lock(commitHookMutex_);
   auto iterator =
       std::find(commitHooks_.begin(), commitHooks_.end(), &commitHook);
   react_native_assert(iterator != commitHooks_.end());
@@ -400,7 +400,7 @@ RootShadowNode::Unshared UIManager::shadowTreeWillCommit(
     ShadowTree const &shadowTree,
     RootShadowNode::Shared const &oldRootShadowNode,
     RootShadowNode::Unshared const &newRootShadowNode) const {
-  std::shared_lock<better::shared_mutex> lock(commitHookMutex_);
+  std::shared_lock<butter::shared_mutex> lock(commitHookMutex_);
 
   auto resultRootShadowNode = newRootShadowNode;
   for (auto const *commitHook : commitHooks_) {

ReactCommon/react/renderer/uimanager/UIManager.h

@@ -194,7 +194,7 @@ class UIManager final : public ShadowTreeDelegate {
   BackgroundExecutor const backgroundExecutor_{};
   ContextContainer::Shared contextContainer_;
 
-  mutable better::shared_mutex commitHookMutex_;
+  mutable butter::shared_mutex commitHookMutex_;
   mutable std::vector<UIManagerCommitHook const *> commitHooks_;
 
   std::unique_ptr<LeakChecker> leakChecker_;

ReactCommon/react/test_utils/BUCK

@@ -42,7 +42,7 @@ rn_xplat_cxx_library(
     visibility = ["PUBLIC"],
     deps = [
         "//xplat/jsi:jsi",
-        react_native_xplat_target("better:better"),
+        react_native_xplat_target("butter:butter"),
         react_native_xplat_target("react/debug:debug"),
     ],
     exported_deps = [

ReactCommon/react/utils/BUCK

@@ -58,7 +58,7 @@ rn_xplat_cxx_library(
         "//xplat/folly:memory",
         "//xplat/folly:molly",
         "//xplat/jsi:jsi",
-        react_native_xplat_target("better:better"),
+        react_native_xplat_target("butter:butter"),
         react_native_xplat_target("react/debug:debug"),
     ],
 )