Move bailouts to as early as possible

facebook · Mar 12, 2018 · 7aa8d48 · 7aa8d48
1 parent 1b3cacd
commit 7aa8d48
Showing 1 changed file with 17 additions and 15 deletions.
diff --git a/packages/react-reconciler/src/ReactFiberBeginWork.js b/packages/react-reconciler/src/ReactFiberBeginWork.js
@@ -849,6 +849,15 @@ export default function<T, P, I, TI, HI, PI, C, CC, CX, PL>(
     const newProps = workInProgress.pendingProps;
     const oldProps = workInProgress.memoizedProps;
 
+    if (hasLegacyContextChanged()) {
+      // Normally we can bail out on props equality but if context has changed
+      // we don't do the bailout and we have to reuse existing props instead.
+    } else if (oldProps === newProps) {
+      workInProgress.stateNode = 0;
+      pushProvider(workInProgress);
+      return bailoutOnAlreadyFinishedWork(current, workInProgress);
+    }
+
     const newValue = newProps.value;
 
     let changedBits: number;
@@ -896,13 +905,6 @@ export default function<T, P, I, TI, HI, PI, C, CC, CX, PL>(
     workInProgress.stateNode = changedBits;
     pushProvider(workInProgress);
 
-    if (hasLegacyContextChanged()) {
-      // Normally we can bail out on props equality but if context has changed
-      // we don't do the bailout and we have to reuse existing props instead.
-    } else if (oldProps === newProps) {
-      return bailoutOnAlreadyFinishedWork(current, workInProgress);
-    }
-
     workInProgress.memoizedProps = newProps;
     const newChildren = newProps.children;
     reconcileChildren(current, workInProgress, newChildren);
@@ -921,7 +923,14 @@ export default function<T, P, I, TI, HI, PI, C, CC, CX, PL>(
     const newValue = context.currentValue;
     const changedBits = context.changedBits;
 
-    if (changedBits !== 0) {
+    if (changedBits === 0) {
+      if (hasLegacyContextChanged()) {
+        // Normally we can bail out on props equality but if context has changed
+        // we don't do the bailout and we have to reuse existing props instead.
+      } else if (oldProps === newProps) {
+        return bailoutOnAlreadyFinishedWork(current, workInProgress);
+      }
+    } else if (changedBits !== 0) {
       // Context change propagation stops at matching consumers, for time-
       // slicing. Continue the propagation here.
       propagateContextChange(
@@ -940,13 +949,6 @@ export default function<T, P, I, TI, HI, PI, C, CC, CX, PL>(
     }
     workInProgress.stateNode = observedBits;
 
-    if (hasLegacyContextChanged()) {
-      // Normally we can bail out on props equality but if context has changed
-      // we don't do the bailout and we have to reuse existing props instead.
-    } else if (changedBits === 0 && oldProps === newProps) {
-      return bailoutOnAlreadyFinishedWork(current, workInProgress);
-    }
-
     workInProgress.memoizedProps = newProps;
     const render = newProps.children;