Centralize props memoization (facebook#13900)

* Move memoizedProps to after beginWork remove memoizeProps helper

We always call this at the end. This is now enforced to line up since
we do the equality check in the beginning of beginWork. So we can't
have special cases.

* Inline the one caller of memoizeState

packages/react-reconciler/src/ReactFiberBeginWork.js

@@ -230,7 +230,6 @@ function updateForwardRef(
     nextChildren,
     renderExpirationTime,
   );
-  memoizeProps(workInProgress, nextProps);
   return workInProgress.child;
 }
 
@@ -282,7 +281,6 @@ function updatePureComponent(
     nextChildren,
     renderExpirationTime,
   );
-  memoizeProps(workInProgress, nextProps);
   return workInProgress.child;
 }
 
@@ -298,7 +296,6 @@ function updateFragment(
     nextChildren,
     renderExpirationTime,
   );
-  memoizeProps(workInProgress, nextChildren);
   return workInProgress.child;
 }
 
@@ -314,7 +311,6 @@ function updateMode(
     nextChildren,
     renderExpirationTime,
   );
-  memoizeProps(workInProgress, nextChildren);
   return workInProgress.child;
 }
 
@@ -334,7 +330,6 @@ function updateProfiler(
     nextChildren,
     renderExpirationTime,
   );
-  memoizeProps(workInProgress, nextProps);
   return workInProgress.child;
 }
 
@@ -378,7 +373,6 @@ function updateFunctionComponent(
     nextChildren,
     renderExpirationTime,
   );
-  memoizeProps(workInProgress, nextProps);
   return workInProgress.child;
 }
 
@@ -539,10 +533,9 @@ function finishClassComponent(
     );
   }
 
-  // Memoize props and state using the values we just used to render.
+  // Memoize state using the values we just used to render.
   // TODO: Restructure so we never read values from the instance.
-  memoizeState(workInProgress, instance.state);
-  memoizeProps(workInProgress, instance.props);
+  workInProgress.memoizedState = instance.state;
 
   // The context might have changed so we need to recalculate it.
   if (hasContext) {
@@ -676,7 +669,6 @@ function updateHostComponent(current, workInProgress, renderExpirationTime) {
   ) {
     // Schedule this fiber to re-render at offscreen priority. Then bailout.
     workInProgress.expirationTime = Never;
-    workInProgress.memoizedProps = nextProps;
     return null;
   }
 
@@ -686,16 +678,13 @@ function updateHostComponent(current, workInProgress, renderExpirationTime) {
     nextChildren,
     renderExpirationTime,
   );
-  memoizeProps(workInProgress, nextProps);
   return workInProgress.child;
 }
 
 function updateHostText(current, workInProgress) {
   if (current === null) {
     tryToClaimNextHydratableInstance(workInProgress);
   }
-  const nextProps = workInProgress.pendingProps;
-  memoizeProps(workInProgress, nextProps);
   // Nothing to do here. This is terminal. We'll do the completion step
   // immediately after.
   return null;
@@ -805,7 +794,6 @@ function mountIndeterminateComponent(
         );
       }
     }
-    workInProgress.memoizedProps = props;
     return child;
   }
 
@@ -954,7 +942,6 @@ function mountIndeterminateComponent(
       }
     }
     reconcileChildren(null, workInProgress, value, renderExpirationTime);
-    memoizeProps(workInProgress, props);
     return workInProgress.child;
   }
 }
@@ -1165,7 +1152,6 @@ function updateSuspenseComponent(
     }
   }
 
-  workInProgress.memoizedProps = nextProps;
   workInProgress.memoizedState = nextState;
   workInProgress.child = child;
   return next;
@@ -1190,15 +1176,13 @@ function updatePortalComponent(
       nextChildren,
       renderExpirationTime,
     );
-    memoizeProps(workInProgress, nextChildren);
   } else {
     reconcileChildren(
       current,
       workInProgress,
       nextChildren,
       renderExpirationTime,
     );
-    memoizeProps(workInProgress, nextChildren);
   }
   return workInProgress.child;
 }
@@ -1215,7 +1199,6 @@ function updateContextProvider(
   const oldProps = workInProgress.memoizedProps;
 
   const newValue = newProps.value;
-  workInProgress.memoizedProps = newProps;
 
   if (__DEV__) {
     const providerPropTypes = workInProgress.type.propTypes;
@@ -1327,7 +1310,6 @@ function updateContextConsumer(
   // React DevTools reads this flag.
   workInProgress.effectTag |= PerformedWork;
   reconcileChildren(current, workInProgress, newChildren, renderExpirationTime);
-  workInProgress.memoizedProps = newProps;
   return workInProgress.child;
 }
 
@@ -1385,17 +1367,6 @@ function bailoutOnAlreadyFinishedWork(
   }
 }
 
-// TODO: Delete memoizeProps/State and move to reconcile/bailout instead
-function memoizeProps(workInProgress: Fiber, nextProps: any) {
-  workInProgress.memoizedProps = nextProps;
-}
-
-function memoizeState(workInProgress: Fiber, nextState: any) {
-  workInProgress.memoizedState = nextState;
-  // Don't reset the updateQueue, in case there are pending updates. Resetting
-  // is handled by processUpdateQueue.
-}
-
 function beginWork(
   current: Fiber | null,
   workInProgress: Fiber,
@@ -1517,7 +1488,6 @@ function beginWork(
         resolveDefaultProps(Component, unresolvedProps),
         renderExpirationTime,
       );
-      workInProgress.memoizedProps = unresolvedProps;
       return child;
     }
     case ClassComponent: {
@@ -1542,7 +1512,6 @@ function beginWork(
         resolveDefaultProps(Component, unresolvedProps),
         renderExpirationTime,
       );
-      workInProgress.memoizedProps = unresolvedProps;
       return child;
     }
     case HostRoot:
@@ -1584,7 +1553,6 @@ function beginWork(
         resolveDefaultProps(Component, unresolvedProps),
         renderExpirationTime,
       );
-      workInProgress.memoizedProps = unresolvedProps;
       return child;
     }
     case Fragment:
@@ -1628,7 +1596,6 @@ function beginWork(
         updateExpirationTime,
         renderExpirationTime,
       );
-      workInProgress.memoizedProps = unresolvedProps;
       return child;
     }
     default:

packages/react-reconciler/src/ReactFiberScheduler.js

@@ -1091,13 +1091,15 @@ function performUnitOfWork(workInProgress: Fiber): Fiber | null {
     }
 
     next = beginWork(current, workInProgress, nextRenderExpirationTime);
+    workInProgress.memoizedProps = workInProgress.pendingProps;
 
     if (workInProgress.mode & ProfileMode) {
       // Record the render duration assuming we didn't bailout (or error).
       stopProfilerTimerIfRunningAndRecordDelta(workInProgress, true);
     }
   } else {
     next = beginWork(current, workInProgress, nextRenderExpirationTime);
+    workInProgress.memoizedProps = workInProgress.pendingProps;
   }
 
   if (__DEV__) {