facebook · gaearon · Oct 20, 2018 · Oct 20, 2018
diff --git a/packages/react-dom/src/__tests__/ReactDOMServerIntegrationSpecialTypes-test.js b/packages/react-dom/src/__tests__/ReactDOMServerIntegrationSpecialTypes-test.js
@@ -15,7 +15,7 @@ let React;
 let ReactDOM;
 let ReactDOMServer;
 let forwardRef;
-let pure;
+let memo;
 let yieldedValues;
 let yieldValue;
 let clearYields;
@@ -27,7 +27,7 @@ function initModules() {
   ReactDOM = require('react-dom');
   ReactDOMServer = require('react-dom/server');
   forwardRef = React.forwardRef;
-  pure = React.pure;
+  memo = React.memo;
 
   yieldedValues = [];
   yieldValue = value => {
@@ -83,7 +83,7 @@ describe('ReactDOMServerIntegration', () => {
     expect(div.textContent).toBe('Test');
   });
 
-  describe('pure functional components', () => {
+  describe('memoized functional components', () => {
     beforeEach(() => {
       resetModules();
     });
@@ -98,39 +98,39 @@ describe('ReactDOMServerIntegration', () => {
     }
 
     itRenders('basic render', async render => {
-      const PureCounter = pure(Counter);
-      const domNode = await render(<PureCounter count={0} />);
+      const MemoCounter = memo(Counter);
+      const domNode = await render(<MemoCounter count={0} />);
       expect(domNode.textContent).toEqual('Count: 0');
     });
 
     itRenders('composition with forwardRef', async render => {
       const RefCounter = (props, ref) => <Counter count={ref.current} />;
-      const PureRefCounter = pure(forwardRef(RefCounter));
+      const MemoRefCounter = memo(forwardRef(RefCounter));
 
       const ref = React.createRef();
       ref.current = 0;
-      await render(<PureRefCounter ref={ref} />);
+      await render(<MemoRefCounter ref={ref} />);
 
       expect(clearYields()).toEqual(['Count: 0']);
     });
 
     itRenders('with comparator', async render => {
-      const PureCounter = pure(Counter, (oldProps, newProps) => false);
-      await render(<PureCounter count={0} />);
+      const MemoCounter = memo(Counter, (oldProps, newProps) => false);
+      await render(<MemoCounter count={0} />);
       expect(clearYields()).toEqual(['Count: 0']);
     });
 
     itRenders(
       'comparator functions are not invoked on the server',
       async render => {
-        const PureCounter = React.pure(Counter, (oldProps, newProps) => {
+        const MemoCounter = React.memo(Counter, (oldProps, newProps) => {
           yieldValue(
             `Old count: ${oldProps.count}, New count: ${newProps.count}`,
           );
           return oldProps.count === newProps.count;
         });
 
-        await render(<PureCounter count={0} />);
+        await render(<MemoCounter count={0} />);
         expect(clearYields()).toEqual(['Count: 0']);
       },
     );

diff --git a/packages/react-dom/src/server/ReactPartialRenderer.js b/packages/react-dom/src/server/ReactPartialRenderer.js
@@ -39,7 +39,7 @@ import {
   REACT_PROVIDER_TYPE,
   REACT_CONTEXT_TYPE,
   REACT_LAZY_TYPE,
-  REACT_PURE_TYPE,
+  REACT_MEMO_TYPE,
 } from 'shared/ReactSymbols';
 
 import {
@@ -1002,7 +1002,7 @@ class ReactDOMServerRenderer {
             this.stack.push(frame);
             return '';
           }
-          case REACT_PURE_TYPE: {
+          case REACT_MEMO_TYPE: {
             const element: ReactElement = ((nextChild: any): ReactElement);
             let nextChildren = [
               React.createElement(

diff --git a/packages/react-reconciler/src/ReactFiber.js b/packages/react-reconciler/src/ReactFiber.js
@@ -35,7 +35,7 @@ import {
   Profiler,
   SuspenseComponent,
   FunctionComponent,
-  PureComponent,
+  MemoComponent,
   LazyComponent,
 } from 'shared/ReactWorkTags';
 import getComponentName from 'shared/getComponentName';
@@ -57,7 +57,7 @@ import {
   REACT_CONTEXT_TYPE,
   REACT_CONCURRENT_MODE_TYPE,
   REACT_SUSPENSE_TYPE,
-  REACT_PURE_TYPE,
+  REACT_MEMO_TYPE,
   REACT_LAZY_TYPE,
 } from 'shared/ReactSymbols';
 
@@ -315,8 +315,8 @@ export function resolveLazyComponentTag(Component: Function): WorkTag {
     if ($$typeof === REACT_FORWARD_REF_TYPE) {
       return ForwardRef;
     }
-    if ($$typeof === REACT_PURE_TYPE) {
-      return PureComponent;
+    if ($$typeof === REACT_MEMO_TYPE) {
+      return MemoComponent;
     }
   }
   return IndeterminateComponent;
@@ -470,8 +470,8 @@ export function createFiberFromTypeAndProps(
             case REACT_FORWARD_REF_TYPE:
               fiberTag = ForwardRef;
               break getTag;
-            case REACT_PURE_TYPE:
-              fiberTag = PureComponent;
+            case REACT_MEMO_TYPE:
+              fiberTag = MemoComponent;
               break getTag;
             case REACT_LAZY_TYPE:
               fiberTag = LazyComponent;

diff --git a/packages/react-reconciler/src/ReactFiberBeginWork.js b/packages/react-reconciler/src/ReactFiberBeginWork.js
@@ -30,8 +30,8 @@ import {
   ContextConsumer,
   Profiler,
   SuspenseComponent,
-  PureComponent,
-  SimplePureComponent,
+  MemoComponent,
+  SimpleMemoComponent,
   LazyComponent,
 } from 'shared/ReactWorkTags';
 import {
@@ -231,7 +231,7 @@ function updateForwardRef(
   return workInProgress.child;
 }
 
-function updatePureComponent(
+function updateMemoComponent(
   current: Fiber | null,
   workInProgress: Fiber,
   Component: any,
@@ -244,10 +244,10 @@ function updatePureComponent(
     if (isSimpleFunctionComponent(type) && Component.compare === null) {
       // If this is a plain function component without default props,
       // and with only the default shallow comparison, we upgrade it
-      // to a SimplePureComponent to allow fast path updates.
-      workInProgress.tag = SimplePureComponent;
+      // to a SimpleMemoComponent to allow fast path updates.
+      workInProgress.tag = SimpleMemoComponent;
       workInProgress.type = type;
-      return updateSimplePureComponent(
+      return updateSimpleMemoComponent(
         current,
         workInProgress,
         type,
@@ -299,7 +299,7 @@ function updatePureComponent(
   return newChild;
 }
 
-function updateSimplePureComponent(
+function updateSimpleMemoComponent(
   current: Fiber | null,
   workInProgress: Fiber,
   Component: any,
@@ -814,8 +814,8 @@ function mountLazyComponent(
       );
       break;
     }
-    case PureComponent: {
-      child = updatePureComponent(
+    case MemoComponent: {
+      child = updateMemoComponent(
         null,
         workInProgress,
         Component,
@@ -826,7 +826,7 @@ function mountLazyComponent(
       break;
     }
     default: {
-      // This message intentionally doesn't metion ForwardRef or PureComponent
+      // This message intentionally doesn't metion ForwardRef or MemoComponent
       // because the fact that it's a separate type of work is an
       // implementation detail.
       invariant(
@@ -1612,11 +1612,11 @@ function beginWork(
         workInProgress,
         renderExpirationTime,
       );
-    case PureComponent: {
+    case MemoComponent: {
       const type = workInProgress.type;
       const unresolvedProps = workInProgress.pendingProps;
       const resolvedProps = resolveDefaultProps(type.type, unresolvedProps);
-      return updatePureComponent(
+      return updateMemoComponent(
         current,
         workInProgress,
         type,
@@ -1625,8 +1625,8 @@ function beginWork(
         renderExpirationTime,
       );
     }
-    case SimplePureComponent: {
-      return updateSimplePureComponent(
+    case SimpleMemoComponent: {
+      return updateSimpleMemoComponent(
         current,
         workInProgress,
         workInProgress.type,

diff --git a/packages/react-reconciler/src/ReactFiberCompleteWork.js b/packages/react-reconciler/src/ReactFiberCompleteWork.js
@@ -34,8 +34,8 @@ import {
   Mode,
   Profiler,
   SuspenseComponent,
-  PureComponent,
-  SimplePureComponent,
+  MemoComponent,
+  SimpleMemoComponent,
   LazyComponent,
 } from 'shared/ReactWorkTags';
 import {Placement, Ref, Update} from 'shared/ReactSideEffectTags';
@@ -540,7 +540,7 @@ function completeWork(
       break;
     case LazyComponent:
       break;
-    case SimplePureComponent:
+    case SimpleMemoComponent:
     case FunctionComponent:
       break;
     case ClassComponent: {
@@ -715,7 +715,7 @@ function completeWork(
       break;
     case ContextConsumer:
       break;
-    case PureComponent:
+    case MemoComponent:
       break;
     default:
       invariant(

diff --git a/packages/react-reconciler/src/__tests__/ReactIncrementalPerf-test.internal.js b/packages/react-reconciler/src/__tests__/ReactIncrementalPerf-test.internal.js
@@ -555,13 +555,13 @@ describe('ReactDebugFiberPerf', () => {
     expect(getFlameChart()).toMatchSnapshot();
   });
 
-  it('supports pure', () => {
-    const PureFoo = React.pure(function Foo() {
+  it('supports memo', () => {
+    const MemoFoo = React.memo(function Foo() {
       return <div />;
     });
     ReactNoop.render(
       <Parent>
-        <PureFoo />
+        <MemoFoo />
       </Parent>,
     );
     ReactNoop.flush();

diff --git a/.../src/__tests__/ReactPure-test.internal.js → .../src/__tests__/ReactMemo-test.internal.js b/.../src/__tests__/ReactPure-test.internal.js → .../src/__tests__/ReactMemo-test.internal.js
@@ -16,7 +16,7 @@ let React;
 let ReactFeatureFlags;
 let ReactNoop;
 
-describe('pure', () => {
+describe('memo', () => {
   beforeEach(() => {
     jest.resetModules();
     ReactFeatureFlags = require('shared/ReactFeatureFlags');
@@ -38,30 +38,30 @@ describe('pure', () => {
     return {default: result};
   }
 
-  // Tests should run against both the lazy and non-lazy versions of `pure`.
+  // Tests should run against both the lazy and non-lazy versions of `memo`.
   // To make the tests work for both versions, we wrap the non-lazy version in
   // a lazy function component.
   sharedTests('normal', (...args) => {
-    const Pure = React.pure(...args);
+    const Memo = React.memo(...args);
     function Indirection(props) {
-      return <Pure {...props} />;
+      return <Memo {...props} />;
     }
     return React.lazy(() => fakeImport(Indirection));
   });
   sharedTests('lazy', (...args) => {
-    const Pure = React.pure(...args);
-    return React.lazy(() => fakeImport(Pure));
+    const Memo = React.memo(...args);
+    return React.lazy(() => fakeImport(Memo));
   });
 
-  function sharedTests(label, pure) {
+  function sharedTests(label, memo) {
     describe(`${label}`, () => {
       it('bails out on props equality', async () => {
         const {unstable_Suspense: Suspense} = React;
 
         function Counter({count}) {
           return <Text text={count} />;
         }
-        Counter = pure(Counter);
+        Counter = memo(Counter);
 
         ReactNoop.render(
           <Suspense fallback={<Text text="Loading..." />}>
@@ -108,7 +108,7 @@ describe('pure', () => {
           const count = readContext(CountContext);
           return <Text text={`${props.label}: ${count}`} />;
         }
-        Counter = pure(Counter);
+        Counter = memo(Counter);
 
         class Parent extends React.Component {
           state = {count: 0};
@@ -147,7 +147,7 @@ describe('pure', () => {
         function Counter({count}) {
           return <Text text={count} />;
         }
-        Counter = pure(Counter, (oldProps, newProps) => {
+        Counter = memo(Counter, (oldProps, newProps) => {
           ReactNoop.yield(
             `Old count: ${oldProps.count}, New count: ${newProps.count}`,
           );
@@ -192,7 +192,7 @@ describe('pure', () => {
             return <Text text={this.props.count + '' + this.props.suffix} />;
           }
         }
-        const Counter = pure(CounterInner);
+        const Counter = memo(CounterInner);
 
         ReactNoop.render(
           <Suspense fallback={<Text text="Loading..." />}>
@@ -224,8 +224,8 @@ describe('pure', () => {
       });
 
       it('warns if first argument is undefined', () => {
-        expect(() => pure()).toWarnDev(
-          'pure: The first argument must be a component. Instead ' +
+        expect(() => memo()).toWarnDev(
+          'memo: The first argument must be a component. Instead ' +
             'received: undefined',
           {withoutStack: true},
         );

diff --git a/...s/react-reconciler/src/__tests__/__snapshots__/ReactIncrementalPerf-test.internal.js.snap b/...s/react-reconciler/src/__tests__/__snapshots__/ReactIncrementalPerf-test.internal.js.snap
@@ -410,7 +410,7 @@ exports[`ReactDebugFiberPerf supports portals 1`] = `
 "
 `;
 
-exports[`ReactDebugFiberPerf supports pure 1`] = `
+exports[`ReactDebugFiberPerf supports memo 1`] = `
 "⚛ (Waiting for async callback... will force flush in 5250 ms)
 
 ⚛ (React Tree Reconciliation: Completed Root)

diff --git a/packages/react-test-renderer/src/ReactTestRenderer.js b/packages/react-test-renderer/src/ReactTestRenderer.js
@@ -27,8 +27,8 @@ import {
   Mode,
   ForwardRef,
   Profiler,
-  PureComponent,
-  SimplePureComponent,
+  MemoComponent,
+  SimpleMemoComponent,
 } from 'shared/ReactWorkTags';
 import invariant from 'shared/invariant';
 import ReactVersion from 'shared/ReactVersion';
@@ -167,7 +167,7 @@ function toTree(node: ?Fiber) {
         rendered: childrenToTree(node.child),
       };
     case FunctionComponent:
-    case SimplePureComponent:
+    case SimpleMemoComponent:
       return {
         nodeType: 'component',
         type: node.type,
@@ -192,7 +192,7 @@ function toTree(node: ?Fiber) {
     case Mode:
     case Profiler:
     case ForwardRef:
-    case PureComponent:
+    case MemoComponent:
       return childrenToTree(node.child);
     default:
       invariant(
@@ -208,7 +208,7 @@ const validWrapperTypes = new Set([
   ClassComponent,
   HostComponent,
   ForwardRef,
-  PureComponent,
+  MemoComponent,
   // Normally skipped, but used when there's more than one root child.
   HostRoot,
 ]);