New commit phase lifecycle: getSnapshotBeforeUpdate (#12404)

* Implemented new getSnapshotBeforeUpdate lifecycle
* Store snapshot value from Fiber to instance (__reactInternalSnapshotBeforeUpdate)
* Use commitAllHostEffects() traversal for getSnapshotBeforeUpdate()
* Added DEV warnings and tests for new lifecycle
* Don't invoke legacy lifecycles if getSnapshotBeforeUpdate() is defined. DEV warn about this.
* Converted did-warn objects to Sets in ReactFiberClassComponent
* Replaced redundant new lifecycle checks in a few methods
* Check for polyfill suppress flag on cWU as well before warning
* Added Snapshot bit to HostEffectMask

src/ReactShallowRenderer.js

@@ -139,20 +139,18 @@ class ReactShallowRenderer {
     ) {
       const beforeState = this._newState;
 
-      if (typeof this._instance.componentWillMount === 'function') {
-        // In order to support react-lifecycles-compat polyfilled components,
-        // Unsafe lifecycles should not be invoked for any component with the new gDSFP.
-        if (typeof element.type.getDerivedStateFromProps !== 'function') {
-          this._instance.componentWillMount();
-        }
-      }
+      // In order to support react-lifecycles-compat polyfilled components,
+      // Unsafe lifecycles should not be invoked for components using the new APIs.
       if (
-        typeof this._instance.UNSAFE_componentWillMount === 'function' &&
-        typeof element.type.getDerivedStateFromProps !== 'function'
+        typeof element.type.getDerivedStateFromProps !== 'function' &&
+        typeof this._instance.getSnapshotBeforeUpdate !== 'function'
       ) {
-        // In order to support react-lifecycles-compat polyfilled components,
-        // Unsafe lifecycles should not be invoked for any component with the new gDSFP.
-        this._instance.UNSAFE_componentWillMount();
+        if (typeof this._instance.componentWillMount === 'function') {
+          this._instance.componentWillMount();
+        }
+        if (typeof this._instance.UNSAFE_componentWillMount === 'function') {
+          this._instance.UNSAFE_componentWillMount();
+        }
       }
 
       // setState may have been called during cWM
@@ -173,20 +171,20 @@ class ReactShallowRenderer {
     const oldProps = this._instance.props;
 
     if (oldProps !== props) {
-      if (typeof this._instance.componentWillReceiveProps === 'function') {
-        // In order to support react-lifecycles-compat polyfilled components,
-        // Unsafe lifecycles should not be invoked for any component with the new gDSFP.
-        if (typeof element.type.getDerivedStateFromProps !== 'function') {
-          this._instance.componentWillReceiveProps(props, context);
-        }
-      }
+      // In order to support react-lifecycles-compat polyfilled components,
+      // Unsafe lifecycles should not be invoked for components using the new APIs.
       if (
-        typeof this._instance.UNSAFE_componentWillReceiveProps === 'function' &&
-        typeof element.type.getDerivedStateFromProps !== 'function'
+        typeof element.type.getDerivedStateFromProps !== 'function' &&
+        typeof this._instance.getSnapshotBeforeUpdate !== 'function'
       ) {
-        // In order to support react-lifecycles-compat polyfilled components,
-        // Unsafe lifecycles should not be invoked for any component with the new gDSFP.
-        this._instance.UNSAFE_componentWillReceiveProps(props, context);
+        if (typeof this._instance.componentWillReceiveProps === 'function') {
+          this._instance.componentWillReceiveProps(props, context);
+        }
+        if (
+          typeof this._instance.UNSAFE_componentWillReceiveProps === 'function'
+        ) {
+          this._instance.UNSAFE_componentWillReceiveProps(props, context);
+        }
       }
 
       this._updateStateFromStaticLifecycle(props);
@@ -211,20 +209,18 @@ class ReactShallowRenderer {
     }
 
     if (shouldUpdate) {
-      if (typeof this._instance.componentWillUpdate === 'function') {
-        // In order to support react-lifecycles-compat polyfilled components,
-        // Unsafe lifecycles should not be invoked for any component with the new gDSFP.
-        if (typeof type.getDerivedStateFromProps !== 'function') {
-          this._instance.componentWillUpdate(props, state, context);
-        }
-      }
+      // In order to support react-lifecycles-compat polyfilled components,
+      // Unsafe lifecycles should not be invoked for components using the new APIs.
       if (
-        typeof this._instance.UNSAFE_componentWillUpdate === 'function' &&
-        typeof type.getDerivedStateFromProps !== 'function'
+        typeof element.type.getDerivedStateFromProps !== 'function' &&
+        typeof this._instance.getSnapshotBeforeUpdate !== 'function'
       ) {
-        // In order to support react-lifecycles-compat polyfilled components,
-        // Unsafe lifecycles should not be invoked for any component with the new gDSFP.
-        this._instance.UNSAFE_componentWillUpdate(props, state, context);
+        if (typeof this._instance.componentWillUpdate === 'function') {
+          this._instance.componentWillUpdate(props, state, context);
+        }
+        if (typeof this._instance.UNSAFE_componentWillUpdate === 'function') {
+          this._instance.UNSAFE_componentWillUpdate(props, state, context);
+        }
       }
     }
 

src/__tests__/ReactShallowRenderer-test.js

@@ -128,6 +128,48 @@ describe('ReactShallowRenderer', () => {
     shallowRenderer.render(<Component />);
   });
 
+  it('should not invoke deprecated lifecycles (cWM/cWRP/cWU) if new getSnapshotBeforeUpdate is present', () => {
+    class Component extends React.Component {
+      getSnapshotBeforeUpdate() {
+        return null;
+      }
+      componentWillMount() {
+        throw Error('unexpected');
+      }
+      componentWillReceiveProps() {
+        throw Error('unexpected');
+      }
+      componentWillUpdate() {
+        throw Error('unexpected');
+      }
+      render() {
+        return null;
+      }
+    }
+
+    const shallowRenderer = createRenderer();
+    shallowRenderer.render(<Component value={1} />);
+    shallowRenderer.render(<Component value={2} />);
+  });
+
+  it('should not call getSnapshotBeforeUpdate or componentDidUpdate when updating since refs wont exist', () => {
+    class Component extends React.Component {
+      getSnapshotBeforeUpdate() {
+        throw Error('unexpected');
+      }
+      componentDidUpdate() {
+        throw Error('unexpected');
+      }
+      render() {
+        return null;
+      }
+    }
+
+    const shallowRenderer = createRenderer();
+    shallowRenderer.render(<Component value={1} />);
+    shallowRenderer.render(<Component value={2} />);
+  });
+
   it('should only render 1 level deep', () => {
     function Parent() {
       return (