Add support for React.memo

Author: Brian Vaughn

backend/attachRendererFiber.js

@@ -106,10 +106,10 @@ function getInternalReactConstants(version) {
     CONTEXT_PROVIDER_SYMBOL_STRING: 'Symbol(react.provider)',
     FORWARD_REF_NUMBER: 0xead0,
     FORWARD_REF_SYMBOL_STRING: 'Symbol(react.forward_ref)',
+    MEMO_NUMBER: 0xead3,
+    MEMO_SYMBOL_STRING: 'Symbol(react.memo)',
     PROFILER_NUMBER: 0xead2,
     PROFILER_SYMBOL_STRING: 'Symbol(react.profiler)',
-    PURE_NUMBER: 0xead3,
-    PURE_SYMBOL_STRING: 'Symbol(react.pure)',
     STRICT_MODE_NUMBER: 0xeacc,
     STRICT_MODE_SYMBOL_STRING: 'Symbol(react.strict_mode)',
     SUSPENSE_NUMBER: 0xead1,
@@ -143,6 +143,8 @@ function attachRendererFiber(hook: Hook, rid: string, renderer: ReactRenderer):
     HostText,
     Fragment,
     ForwardRef,
+    MemoComponent,
+    SimpleMemoComponent,
   } = ReactTypeOfWork;
   var {
     CONCURRENT_MODE_NUMBER,
@@ -154,8 +156,6 @@ function attachRendererFiber(hook: Hook, rid: string, renderer: ReactRenderer):
     CONTEXT_PROVIDER_SYMBOL_STRING,
     PROFILER_NUMBER,
     PROFILER_SYMBOL_STRING,
-    PURE_NUMBER,
-    PURE_SYMBOL_STRING,
     STRICT_MODE_NUMBER,
     STRICT_MODE_SYMBOL_STRING,
     SUSPENSE_NUMBER,
@@ -166,6 +166,7 @@ function attachRendererFiber(hook: Hook, rid: string, renderer: ReactRenderer):
   // TODO: we might want to change the data structure
   // once we no longer suppport Stack versions of `getData`.
   function getDataFiber(fiber: Object): DataType {
+    var elementType = fiber.elementType;
     var type = fiber.type;
     var key = fiber.key;
     var ref = fiber.ref;
@@ -279,6 +280,17 @@ function attachRendererFiber(hook: Hook, rid: string, renderer: ReactRenderer):
         nodeType = 'Wrapper';
         children = [];
         break;
+      case MemoComponent:
+      case SimpleMemoComponent:
+        nodeType = 'Special';
+        if (elementType.displayName) {
+          name = elementType.displayName;
+        } else {
+          const displayName = type.displayName || type.name;
+          name = displayName ? `Memo(${displayName})` : 'Memo';
+        }
+        children = [];
+        break;
       default:
         const symbolOrNumber = typeof type === 'object' && type !== null
           ? type.$$typeof
@@ -289,17 +301,6 @@ function attachRendererFiber(hook: Hook, rid: string, renderer: ReactRenderer):
           : symbolOrNumber;
 
         switch (switchValue) {
-          case PURE_NUMBER:
-          case PURE_SYMBOL_STRING:
-            nodeType = 'Special';
-            if (type.displayName) {
-              name = type.displayName;
-            } else {
-              const displayName = type.render.displayName || type.render.name;
-              name = displayName ? `Pure(${displayName})` : 'Pure';
-            }
-            children = [];
-            break;
           case CONCURRENT_MODE_NUMBER:
           case CONCURRENT_MODE_SYMBOL_STRING:
           case DEPRECATED_ASYNC_MODE_SYMBOL_STRING: