From 6aa9b2be2c79da0f3d93f390d5eb9e9bcd96174e Mon Sep 17 00:00:00 2001
From: Brian Vaughn <brian.david.vaughn@gmail.com>
Date: Wed, 21 Mar 2018 11:47:40 -0700
Subject: [PATCH 1/5] Expanded DEV-only warnings for gDSFP and legacy
 lifecycles

---
 .../__tests__/ReactComponentLifeCycle-test.js | 82 ++++++++++++++++-
 .../src/ReactFiberClassComponent.js           | 88 ++++++++++--------
 .../src/ReactShallowRenderer.js               | 47 ++++++----
 .../__tests__/ReactShallowRenderer-test.js    | 90 +++++++++++++++++--
 .../createReactClassIntegration-test.js       |  8 +-
 5 files changed, 254 insertions(+), 61 deletions(-)

diff --git a/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js b/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
index aa81546bd21..ee7253f5081 100644
--- a/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
+++ b/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
@@ -669,7 +669,7 @@ describe('ReactComponentLifeCycle', () => {
 
     const container = document.createElement('div');
     expect(() => ReactDOM.render(<Component />, container)).toWarnDev(
-      'Defines both componentWillReceiveProps',
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.',
     );
   });
 
@@ -695,7 +695,85 @@ describe('ReactComponentLifeCycle', () => {
 
     const container = document.createElement('div');
     expect(() => ReactDOM.render(<Component />, container)).toWarnDev(
-      'Defines both componentWillReceiveProps',
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.',
+    );
+  });
+
+  it('should warn about deprecated lifecycles (cWM/cWRP/cWU) if new static gDSFP is present', () => {
+    const container = document.createElement('div');
+
+    class AllLegacyLifecycles extends React.Component {
+      state = {};
+      static getDerivedStateFromProps() {
+        return null;
+      }
+      componentWillMount() {}
+      componentWillReceiveProps() {}
+      componentWillUpdate() {}
+      render() {
+        return null;
+      }
+    }
+
+    expect(() => ReactDOM.render(<AllLegacyLifecycles />, container)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'AllLegacyLifecycles uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillMount\n' +
+        '  componentWillReceiveProps\n' +
+        '  componentWillUpdate',
+    );
+
+    class WillMount extends React.Component {
+      state = {};
+      static getDerivedStateFromProps() {
+        return null;
+      }
+      componentWillMount() {}
+      render() {
+        return null;
+      }
+    }
+
+    expect(() => ReactDOM.render(<WillMount />, container)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'WillMount uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillMount',
+    );
+
+    class WillMountAndUpdate extends React.Component {
+      state = {};
+      static getDerivedStateFromProps() {
+        return null;
+      }
+      componentWillMount() {}
+      componentWillUpdate() {}
+      render() {
+        return null;
+      }
+    }
+
+    expect(() => ReactDOM.render(<WillMountAndUpdate />, container)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'WillMountAndUpdate uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillMount\n' +
+        '  componentWillUpdate',
+    );
+
+    class WillReceiveProps extends React.Component {
+      state = {};
+      static getDerivedStateFromProps() {
+        return null;
+      }
+      componentWillReceiveProps() {}
+      render() {
+        return null;
+      }
+    }
+
+    expect(() => ReactDOM.render(<WillReceiveProps />, container)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'WillReceiveProps uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillReceiveProps',
     );
   });
 
diff --git a/packages/react-reconciler/src/ReactFiberClassComponent.js b/packages/react-reconciler/src/ReactFiberClassComponent.js
index 7f0514f6e41..e1d6cb0b0d6 100644
--- a/packages/react-reconciler/src/ReactFiberClassComponent.js
+++ b/packages/react-reconciler/src/ReactFiberClassComponent.js
@@ -41,14 +41,14 @@ const isArray = Array.isArray;
 let didWarnAboutStateAssignmentForComponent;
 let didWarnAboutUndefinedDerivedState;
 let didWarnAboutUninitializedState;
-let didWarnAboutWillReceivePropsAndDerivedState;
+let didWarnAboutLegacyLifecyclesAndDerivedState;
 let warnOnInvalidCallback;
 
 if (__DEV__) {
   didWarnAboutStateAssignmentForComponent = {};
   didWarnAboutUndefinedDerivedState = {};
   didWarnAboutUninitializedState = {};
-  didWarnAboutWillReceivePropsAndDerivedState = {};
+  didWarnAboutLegacyLifecyclesAndDerivedState = {};
 
   const didWarnOnInvalidCallback = {};
 
@@ -424,20 +424,54 @@ export default function(
     adoptClassInstance(workInProgress, instance);
 
     if (__DEV__) {
-      if (
-        typeof ctor.getDerivedStateFromProps === 'function' &&
-        state === null
-      ) {
-        const componentName = getComponentName(workInProgress) || 'Unknown';
-        if (!didWarnAboutUninitializedState[componentName]) {
-          warning(
-            false,
-            '%s: Did not properly initialize state during construction. ' +
-              'Expected state to be an object, but it was %s.',
-            componentName,
-            instance.state === null ? 'null' : 'undefined',
-          );
-          didWarnAboutUninitializedState[componentName] = true;
+      if (typeof ctor.getDerivedStateFromProps === 'function') {
+        if (state === null) {
+          const componentName = getComponentName(workInProgress) || 'Unknown';
+          if (!didWarnAboutUninitializedState[componentName]) {
+            warning(
+              false,
+              '%s: Did not properly initialize state during construction. ' +
+                'Expected state to be an object, but it was %s.',
+              componentName,
+              instance.state === null ? 'null' : 'undefined',
+            );
+            didWarnAboutUninitializedState[componentName] = true;
+          }
+        }
+
+        // If getDerivedStateFromProps() is defined, "unsafe" lifecycles won't be called.
+        // Warn about these lifecycles if they are present.
+        // Don't warn about react-lifecycles-compat polyfilled methods though.
+        const definesWillMount =
+          (typeof instance.componentWillMount === 'function' &&
+            instance.componentWillMount.__suppressDeprecationWarning !==
+              true) ||
+          typeof instance.UNSAFE_componentWillMount === 'function';
+        const definesWillReceiveProps =
+          (typeof instance.componentWillReceiveProps === 'function' &&
+            instance.componentWillReceiveProps.__suppressDeprecationWarning !==
+              true) ||
+          typeof instance.UNSAFE_componentWillReceiveProps === 'function';
+        const definesWillUpdate =
+          typeof instance.componentWillUpdate === 'function' ||
+          typeof instance.UNSAFE_componentWillUpdate === 'function';
+
+        if (definesWillMount || definesWillReceiveProps || definesWillUpdate) {
+          const componentName = getComponentName(workInProgress) || 'Unknown';
+          if (!didWarnAboutLegacyLifecyclesAndDerivedState[componentName]) {
+            warning(
+              false,
+              'Unsafe legacy lifecycles will not be called for components using ' +
+                'the new getDerivedStateFromProps() API.\n\n' +
+                '%s uses getDerivedStateFromProps() but also contains the following legacy lifecycles:' +
+                '%s%s%s',
+              componentName,
+              definesWillMount ? '\n  componentWillMount' : '',
+              definesWillReceiveProps ? '\n  componentWillReceiveProps' : '',
+              definesWillUpdate ? '\n  componentWillUpdate' : '',
+            );
+            didWarnAboutLegacyLifecyclesAndDerivedState[componentName] = true;
+          }
         }
       }
     }
@@ -539,28 +573,6 @@ export default function(
     const {type} = workInProgress;
 
     if (typeof type.getDerivedStateFromProps === 'function') {
-      if (__DEV__) {
-        // Don't warn about react-lifecycles-compat polyfilled components
-        if (
-          (typeof instance.componentWillReceiveProps === 'function' &&
-            instance.componentWillReceiveProps.__suppressDeprecationWarning !==
-              true) ||
-          typeof instance.UNSAFE_componentWillReceiveProps === 'function'
-        ) {
-          const componentName = getComponentName(workInProgress) || 'Unknown';
-          if (!didWarnAboutWillReceivePropsAndDerivedState[componentName]) {
-            warning(
-              false,
-              '%s: Defines both componentWillReceiveProps() and static ' +
-                'getDerivedStateFromProps() methods. We recommend using ' +
-                'only getDerivedStateFromProps().',
-              componentName,
-            );
-            didWarnAboutWillReceivePropsAndDerivedState[componentName] = true;
-          }
-        }
-      }
-
       if (
         debugRenderPhaseSideEffects ||
         (debugRenderPhaseSideEffectsForStrictMode &&
diff --git a/packages/react-test-renderer/src/ReactShallowRenderer.js b/packages/react-test-renderer/src/ReactShallowRenderer.js
index b08732e0fd3..6cd713b6275 100644
--- a/packages/react-test-renderer/src/ReactShallowRenderer.js
+++ b/packages/react-test-renderer/src/ReactShallowRenderer.js
@@ -23,7 +23,7 @@ let didWarnAboutLegacyWillReceiveProps;
 let didWarnAboutLegacyWillUpdate;
 let didWarnAboutUndefinedDerivedState;
 let didWarnAboutUninitializedState;
-let didWarnAboutWillReceivePropsAndDerivedState;
+let didWarnAboutLegacyLifecyclesAndDerivedState;
 
 if (__DEV__) {
   if (warnAboutDeprecatedLifecycles) {
@@ -33,7 +33,7 @@ if (__DEV__) {
   }
   didWarnAboutUndefinedDerivedState = {};
   didWarnAboutUninitializedState = {};
-  didWarnAboutWillReceivePropsAndDerivedState = {};
+  didWarnAboutLegacyLifecyclesAndDerivedState = {};
 }
 
 class ReactShallowRenderer {
@@ -352,23 +352,40 @@ class ReactShallowRenderer {
 
     if (typeof type.getDerivedStateFromProps === 'function') {
       if (__DEV__) {
-        // Don't warn about react-lifecycles-compat polyfilled components
-        if (
-          (typeof this._instance.componentWillReceiveProps === 'function' &&
-            this._instance.componentWillReceiveProps
-              .__suppressDeprecationWarning !== true) ||
-          typeof this._instance.UNSAFE_componentWillReceiveProps === 'function'
-        ) {
-          const componentName = getName(type, this._instance);
-          if (!didWarnAboutWillReceivePropsAndDerivedState[componentName]) {
+        const instance = this._instance;
+
+        // If getDerivedStateFromProps() is defined, "unsafe" lifecycles won't be called.
+        // Warn about these lifecycles if they are present.
+        // Don't warn about react-lifecycles-compat polyfilled methods though.
+        const definesWillMount =
+          (typeof instance.componentWillMount === 'function' &&
+            instance.componentWillMount.__suppressDeprecationWarning !==
+              true) ||
+          typeof instance.UNSAFE_componentWillMount === 'function';
+        const definesWillReceiveProps =
+          (typeof instance.componentWillReceiveProps === 'function' &&
+            instance.componentWillReceiveProps.__suppressDeprecationWarning !==
+              true) ||
+          typeof instance.UNSAFE_componentWillReceiveProps === 'function';
+        const definesWillUpdate =
+          typeof instance.componentWillUpdate === 'function' ||
+          typeof instance.UNSAFE_componentWillUpdate === 'function';
+
+        if (definesWillMount || definesWillReceiveProps || definesWillUpdate) {
+          const componentName = getName(type, instance);
+          if (!didWarnAboutLegacyLifecyclesAndDerivedState[componentName]) {
             warning(
               false,
-              '%s: Defines both componentWillReceiveProps() and static ' +
-                'getDerivedStateFromProps() methods. We recommend using ' +
-                'only getDerivedStateFromProps().',
+              'Unsafe legacy lifecycles will not be called for components using ' +
+                'the new getDerivedStateFromProps() API.\n\n' +
+                '%s uses getDerivedStateFromProps() but also contains the following legacy lifecycles:' +
+                '%s%s%s',
               componentName,
+              definesWillMount ? '\n  componentWillMount' : '',
+              definesWillReceiveProps ? '\n  componentWillReceiveProps' : '',
+              definesWillUpdate ? '\n  componentWillUpdate' : '',
             );
-            didWarnAboutWillReceivePropsAndDerivedState[componentName] = true;
+            didWarnAboutLegacyLifecyclesAndDerivedState[componentName] = true;
           }
         }
       }
diff --git a/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js b/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
index 2bf95824c32..855a0d7214c 100644
--- a/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
+++ b/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
@@ -125,8 +125,90 @@ describe('ReactShallowRenderer', () => {
     }
 
     const shallowRenderer = createRenderer();
-    expect(() => shallowRenderer.render(<Component foo={2} />)).toWarnDev(
-      'Defines both componentWillReceiveProps() and static getDerivedStateFromProps()',
+    expect(() => shallowRenderer.render(<Component />)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.',
+    );
+  });
+
+  it('should warn about deprecated lifecycles (cWM/cWRP/cWU) if new static gDSFP is present', () => {
+    let shallowRenderer;
+
+    class AllLegacyLifecycles extends React.Component {
+      state = {};
+      static getDerivedStateFromProps() {
+        return null;
+      }
+      componentWillMount() {}
+      componentWillReceiveProps() {}
+      componentWillUpdate() {}
+      render() {
+        return null;
+      }
+    }
+
+    shallowRenderer = createRenderer();
+    expect(() => shallowRenderer.render(<AllLegacyLifecycles />)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'AllLegacyLifecycles uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillMount\n' +
+        '  componentWillReceiveProps\n' +
+        '  componentWillUpdate',
+    );
+
+    class WillMount extends React.Component {
+      state = {};
+      static getDerivedStateFromProps() {
+        return null;
+      }
+      componentWillMount() {}
+      render() {
+        return null;
+      }
+    }
+
+    shallowRenderer = createRenderer();
+    expect(() => shallowRenderer.render(<WillMount />)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'WillMount uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillMount',
+    );
+
+    class WillMountAndUpdate extends React.Component {
+      state = {};
+      static getDerivedStateFromProps() {
+        return null;
+      }
+      componentWillMount() {}
+      componentWillUpdate() {}
+      render() {
+        return null;
+      }
+    }
+
+    shallowRenderer = createRenderer();
+    expect(() => shallowRenderer.render(<WillMountAndUpdate />)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'WillMountAndUpdate uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillMount\n' +
+        '  componentWillUpdate',
+    );
+
+    class WillReceiveProps extends React.Component {
+      state = {};
+      static getDerivedStateFromProps() {
+        return null;
+      }
+      componentWillReceiveProps() {}
+      render() {
+        return null;
+      }
+    }
+
+    shallowRenderer = createRenderer();
+    expect(() => shallowRenderer.render(<WillReceiveProps />)).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'WillReceiveProps uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillReceiveProps',
     );
   });
 
@@ -1238,9 +1320,7 @@ describe('ReactShallowRenderer', () => {
 
     const shallowRenderer = createRenderer();
     expect(() => shallowRenderer.render(<ComponentWithWarnings />)).toWarnDev(
-      'ComponentWithWarnings: Defines both componentWillReceiveProps() and static ' +
-        'getDerivedStateFromProps() methods. We recommend using ' +
-        'only getDerivedStateFromProps().',
+      'ComponentWithWarnings uses getDerivedStateFromProps() but also contains the following legacy lifecycles',
     );
 
     // Should not log duplicate warning
diff --git a/packages/react/src/__tests__/createReactClassIntegration-test.js b/packages/react/src/__tests__/createReactClassIntegration-test.js
index c567b4fd853..76dbe49c4fb 100644
--- a/packages/react/src/__tests__/createReactClassIntegration-test.js
+++ b/packages/react/src/__tests__/createReactClassIntegration-test.js
@@ -475,7 +475,13 @@ describe('create-react-class-integration', () => {
 
     expect(() => {
       ReactDOM.render(<Component />, document.createElement('div'));
-    }).toWarnDev('Defines both componentWillReceiveProps');
+    }).toWarnDev(
+      'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
+        'Unknown uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        '  componentWillMount\n' +
+        '  componentWillReceiveProps\n' +
+        '  componentWillUpdate',
+    );
     ReactDOM.render(<Component foo={1} />, document.createElement('div'));
   });
 

From 1844e385cb3f07b6840d5ce9f99a8446b92cb50e Mon Sep 17 00:00:00 2001
From: Brian Vaughn <brian.david.vaughn@gmail.com>
Date: Thu, 22 Mar 2018 10:02:34 -0700
Subject: [PATCH 2/5] Expanded warning message to add fb.me link for more info

---
 .../__tests__/ReactComponentLifeCycle-test.js    | 16 ++++++++++++----
 .../src/ReactFiberClassComponent.js              |  4 +++-
 .../src/ReactShallowRenderer.js                  |  4 +++-
 .../src/__tests__/ReactShallowRenderer-test.js   | 16 ++++++++++++----
 .../createReactClassIntegration-test.js          |  4 +++-
 5 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js b/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
index ee7253f5081..d52940d2b50 100644
--- a/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
+++ b/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
@@ -720,7 +720,9 @@ describe('ReactComponentLifeCycle', () => {
         'AllLegacyLifecycles uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
         '  componentWillReceiveProps\n' +
-        '  componentWillUpdate',
+        '  componentWillUpdate\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
 
     class WillMount extends React.Component {
@@ -737,7 +739,9 @@ describe('ReactComponentLifeCycle', () => {
     expect(() => ReactDOM.render(<WillMount />, container)).toWarnDev(
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillMount uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
-        '  componentWillMount',
+        '  componentWillMount\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
 
     class WillMountAndUpdate extends React.Component {
@@ -756,7 +760,9 @@ describe('ReactComponentLifeCycle', () => {
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillMountAndUpdate uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
-        '  componentWillUpdate',
+        '  componentWillUpdate\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
 
     class WillReceiveProps extends React.Component {
@@ -773,7 +779,9 @@ describe('ReactComponentLifeCycle', () => {
     expect(() => ReactDOM.render(<WillReceiveProps />, container)).toWarnDev(
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillReceiveProps uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
-        '  componentWillReceiveProps',
+        '  componentWillReceiveProps\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
   });
 
diff --git a/packages/react-reconciler/src/ReactFiberClassComponent.js b/packages/react-reconciler/src/ReactFiberClassComponent.js
index e1d6cb0b0d6..c43b8b01381 100644
--- a/packages/react-reconciler/src/ReactFiberClassComponent.js
+++ b/packages/react-reconciler/src/ReactFiberClassComponent.js
@@ -464,7 +464,9 @@ export default function(
               'Unsafe legacy lifecycles will not be called for components using ' +
                 'the new getDerivedStateFromProps() API.\n\n' +
                 '%s uses getDerivedStateFromProps() but also contains the following legacy lifecycles:' +
-                '%s%s%s',
+                '%s%s%s\n\n' +
+                'The above lifecycles should be removed. Learn more about this warning here:\n' +
+                'https://fb.me/react-async-component-lifecycle-hooks',
               componentName,
               definesWillMount ? '\n  componentWillMount' : '',
               definesWillReceiveProps ? '\n  componentWillReceiveProps' : '',
diff --git a/packages/react-test-renderer/src/ReactShallowRenderer.js b/packages/react-test-renderer/src/ReactShallowRenderer.js
index 6cd713b6275..945ed7c3d07 100644
--- a/packages/react-test-renderer/src/ReactShallowRenderer.js
+++ b/packages/react-test-renderer/src/ReactShallowRenderer.js
@@ -379,7 +379,9 @@ class ReactShallowRenderer {
               'Unsafe legacy lifecycles will not be called for components using ' +
                 'the new getDerivedStateFromProps() API.\n\n' +
                 '%s uses getDerivedStateFromProps() but also contains the following legacy lifecycles:' +
-                '%s%s%s',
+                '%s%s%s\n\n' +
+                'The above lifecycles should be removed. Learn more about this warning here:\n' +
+                'https://fb.me/react-async-component-lifecycle-hooks',
               componentName,
               definesWillMount ? '\n  componentWillMount' : '',
               definesWillReceiveProps ? '\n  componentWillReceiveProps' : '',
diff --git a/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js b/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
index 855a0d7214c..e161291727d 100644
--- a/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
+++ b/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
@@ -152,7 +152,9 @@ describe('ReactShallowRenderer', () => {
         'AllLegacyLifecycles uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
         '  componentWillReceiveProps\n' +
-        '  componentWillUpdate',
+        '  componentWillUpdate\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
 
     class WillMount extends React.Component {
@@ -170,7 +172,9 @@ describe('ReactShallowRenderer', () => {
     expect(() => shallowRenderer.render(<WillMount />)).toWarnDev(
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillMount uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
-        '  componentWillMount',
+        '  componentWillMount\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
 
     class WillMountAndUpdate extends React.Component {
@@ -190,7 +194,9 @@ describe('ReactShallowRenderer', () => {
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillMountAndUpdate uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
-        '  componentWillUpdate',
+        '  componentWillUpdate\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
 
     class WillReceiveProps extends React.Component {
@@ -208,7 +214,9 @@ describe('ReactShallowRenderer', () => {
     expect(() => shallowRenderer.render(<WillReceiveProps />)).toWarnDev(
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillReceiveProps uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
-        '  componentWillReceiveProps',
+        '  componentWillReceiveProps\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
   });
 
diff --git a/packages/react/src/__tests__/createReactClassIntegration-test.js b/packages/react/src/__tests__/createReactClassIntegration-test.js
index 76dbe49c4fb..5ef8248177c 100644
--- a/packages/react/src/__tests__/createReactClassIntegration-test.js
+++ b/packages/react/src/__tests__/createReactClassIntegration-test.js
@@ -480,7 +480,9 @@ describe('create-react-class-integration', () => {
         'Unknown uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
         '  componentWillReceiveProps\n' +
-        '  componentWillUpdate',
+        '  componentWillUpdate\n\n' +
+        'The above lifecycles should be removed. Learn more about this warning here:\n' +
+        'https://fb.me/react-async-component-lifecycle-hooks',
     );
     ReactDOM.render(<Component foo={1} />, document.createElement('div'));
   });

From 04d2b35f148185caf7368f9424e902f7476063b4 Mon Sep 17 00:00:00 2001
From: Brian Vaughn <brian.david.vaughn@gmail.com>
Date: Thu, 22 Mar 2018 10:21:14 -0700
Subject: [PATCH 3/5] Changed default warning component name from 'Unknown' to
 'Component'

---
 packages/react-reconciler/src/ReactFiberClassComponent.js       | 2 +-
 packages/react-test-renderer/src/ReactShallowRenderer.js        | 2 +-
 .../react/src/__tests__/createReactClassIntegration-test.js     | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/react-reconciler/src/ReactFiberClassComponent.js b/packages/react-reconciler/src/ReactFiberClassComponent.js
index c43b8b01381..9fbecc3da6c 100644
--- a/packages/react-reconciler/src/ReactFiberClassComponent.js
+++ b/packages/react-reconciler/src/ReactFiberClassComponent.js
@@ -457,7 +457,7 @@ export default function(
           typeof instance.UNSAFE_componentWillUpdate === 'function';
 
         if (definesWillMount || definesWillReceiveProps || definesWillUpdate) {
-          const componentName = getComponentName(workInProgress) || 'Unknown';
+          const componentName = getComponentName(workInProgress) || 'Component';
           if (!didWarnAboutLegacyLifecyclesAndDerivedState[componentName]) {
             warning(
               false,
diff --git a/packages/react-test-renderer/src/ReactShallowRenderer.js b/packages/react-test-renderer/src/ReactShallowRenderer.js
index 945ed7c3d07..c6d8711d378 100644
--- a/packages/react-test-renderer/src/ReactShallowRenderer.js
+++ b/packages/react-test-renderer/src/ReactShallowRenderer.js
@@ -372,7 +372,7 @@ class ReactShallowRenderer {
           typeof instance.UNSAFE_componentWillUpdate === 'function';
 
         if (definesWillMount || definesWillReceiveProps || definesWillUpdate) {
-          const componentName = getName(type, instance);
+          const componentName = getName(type, instance) || 'Component';
           if (!didWarnAboutLegacyLifecyclesAndDerivedState[componentName]) {
             warning(
               false,
diff --git a/packages/react/src/__tests__/createReactClassIntegration-test.js b/packages/react/src/__tests__/createReactClassIntegration-test.js
index 5ef8248177c..3f15707f786 100644
--- a/packages/react/src/__tests__/createReactClassIntegration-test.js
+++ b/packages/react/src/__tests__/createReactClassIntegration-test.js
@@ -477,7 +477,7 @@ describe('create-react-class-integration', () => {
       ReactDOM.render(<Component />, document.createElement('div'));
     }).toWarnDev(
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
-        'Unknown uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
+        'Component uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
         '  componentWillReceiveProps\n' +
         '  componentWillUpdate\n\n' +

From 611ddca18ba6eb3e8662d88f047c53158b6d76c7 Mon Sep 17 00:00:00 2001
From: Brian Vaughn <brian.david.vaughn@gmail.com>
Date: Thu, 22 Mar 2018 10:59:21 -0700
Subject: [PATCH 4/5] Imrpove gDSFP dev warning to show specific lifecycle name
 (e.g. cWM or UNSAFE_cWM)

---
 .../__tests__/ReactComponentLifeCycle-test.js | 12 ++---
 .../src/ReactFiberClassComponent.js           | 53 ++++++++++++-------
 .../src/ReactShallowRenderer.js               | 53 ++++++++++++-------
 .../__tests__/ReactShallowRenderer-test.js    | 12 ++---
 4 files changed, 82 insertions(+), 48 deletions(-)

diff --git a/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js b/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
index 88b2f888271..0788c871157 100644
--- a/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
+++ b/packages/react-dom/src/__tests__/ReactComponentLifeCycle-test.js
@@ -708,7 +708,7 @@ describe('ReactComponentLifeCycle', () => {
         return null;
       }
       componentWillMount() {}
-      componentWillReceiveProps() {}
+      UNSAFE_componentWillReceiveProps() {}
       componentWillUpdate() {}
       render() {
         return null;
@@ -719,7 +719,7 @@ describe('ReactComponentLifeCycle', () => {
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'AllLegacyLifecycles uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
-        '  componentWillReceiveProps\n' +
+        '  UNSAFE_componentWillReceiveProps\n' +
         '  componentWillUpdate\n\n' +
         'The above lifecycles should be removed. Learn more about this warning here:\n' +
         'https://fb.me/react-async-component-lifecycle-hooks',
@@ -730,7 +730,7 @@ describe('ReactComponentLifeCycle', () => {
       static getDerivedStateFromProps() {
         return null;
       }
-      componentWillMount() {}
+      UNSAFE_componentWillMount() {}
       render() {
         return null;
       }
@@ -739,7 +739,7 @@ describe('ReactComponentLifeCycle', () => {
     expect(() => ReactDOM.render(<WillMount />, container)).toWarnDev(
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillMount uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
-        '  componentWillMount\n\n' +
+        '  UNSAFE_componentWillMount\n\n' +
         'The above lifecycles should be removed. Learn more about this warning here:\n' +
         'https://fb.me/react-async-component-lifecycle-hooks',
     );
@@ -750,7 +750,7 @@ describe('ReactComponentLifeCycle', () => {
         return null;
       }
       componentWillMount() {}
-      componentWillUpdate() {}
+      UNSAFE_componentWillUpdate() {}
       render() {
         return null;
       }
@@ -760,7 +760,7 @@ describe('ReactComponentLifeCycle', () => {
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillMountAndUpdate uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
-        '  componentWillUpdate\n\n' +
+        '  UNSAFE_componentWillUpdate\n\n' +
         'The above lifecycles should be removed. Learn more about this warning here:\n' +
         'https://fb.me/react-async-component-lifecycle-hooks',
     );
diff --git a/packages/react-reconciler/src/ReactFiberClassComponent.js b/packages/react-reconciler/src/ReactFiberClassComponent.js
index 72bcd02893f..5240f16b736 100644
--- a/packages/react-reconciler/src/ReactFiberClassComponent.js
+++ b/packages/react-reconciler/src/ReactFiberClassComponent.js
@@ -437,21 +437,38 @@ export default function(
         // If getDerivedStateFromProps() is defined, "unsafe" lifecycles won't be called.
         // Warn about these lifecycles if they are present.
         // Don't warn about react-lifecycles-compat polyfilled methods though.
-        const definesWillMount =
-          (typeof instance.componentWillMount === 'function' &&
-            instance.componentWillMount.__suppressDeprecationWarning !==
-              true) ||
-          typeof instance.UNSAFE_componentWillMount === 'function';
-        const definesWillReceiveProps =
-          (typeof instance.componentWillReceiveProps === 'function' &&
-            instance.componentWillReceiveProps.__suppressDeprecationWarning !==
-              true) ||
-          typeof instance.UNSAFE_componentWillReceiveProps === 'function';
-        const definesWillUpdate =
-          typeof instance.componentWillUpdate === 'function' ||
-          typeof instance.UNSAFE_componentWillUpdate === 'function';
-
-        if (definesWillMount || definesWillReceiveProps || definesWillUpdate) {
+        let willMount = null;
+        let willReceiveProps = null;
+        let willUpdate = null;
+        if (
+          typeof instance.componentWillMount === 'function' &&
+          instance.componentWillMount.__suppressDeprecationWarning !== true
+        ) {
+          willMount = 'componentWillMount';
+        } else if (typeof instance.UNSAFE_componentWillMount === 'function') {
+          willMount = 'UNSAFE_componentWillMount';
+        }
+        if (
+          typeof instance.componentWillReceiveProps === 'function' &&
+          instance.componentWillReceiveProps.__suppressDeprecationWarning !==
+            true
+        ) {
+          willReceiveProps = 'componentWillReceiveProps';
+        } else if (
+          typeof instance.UNSAFE_componentWillReceiveProps === 'function'
+        ) {
+          willReceiveProps = 'UNSAFE_componentWillReceiveProps';
+        }
+        if (typeof instance.componentWillUpdate === 'function') {
+          willUpdate = 'componentWillUpdate';
+        } else if (typeof instance.UNSAFE_componentWillUpdate === 'function') {
+          willUpdate = 'UNSAFE_componentWillUpdate';
+        }
+        if (
+          willMount !== null ||
+          willReceiveProps !== null ||
+          willUpdate !== null
+        ) {
           const componentName = getComponentName(workInProgress) || 'Component';
           if (!didWarnAboutLegacyLifecyclesAndDerivedState[componentName]) {
             warning(
@@ -463,9 +480,9 @@ export default function(
                 'The above lifecycles should be removed. Learn more about this warning here:\n' +
                 'https://fb.me/react-async-component-lifecycle-hooks',
               componentName,
-              definesWillMount ? '\n  componentWillMount' : '',
-              definesWillReceiveProps ? '\n  componentWillReceiveProps' : '',
-              definesWillUpdate ? '\n  componentWillUpdate' : '',
+              willMount !== null ? `\n  ${willMount}` : '',
+              willReceiveProps !== null ? `\n  ${willReceiveProps}` : '',
+              willUpdate !== null ? `\n  ${willUpdate}` : '',
             );
             didWarnAboutLegacyLifecyclesAndDerivedState[componentName] = true;
           }
diff --git a/packages/react-test-renderer/src/ReactShallowRenderer.js b/packages/react-test-renderer/src/ReactShallowRenderer.js
index c6d8711d378..9dc7b5d2cbd 100644
--- a/packages/react-test-renderer/src/ReactShallowRenderer.js
+++ b/packages/react-test-renderer/src/ReactShallowRenderer.js
@@ -357,21 +357,38 @@ class ReactShallowRenderer {
         // If getDerivedStateFromProps() is defined, "unsafe" lifecycles won't be called.
         // Warn about these lifecycles if they are present.
         // Don't warn about react-lifecycles-compat polyfilled methods though.
-        const definesWillMount =
-          (typeof instance.componentWillMount === 'function' &&
-            instance.componentWillMount.__suppressDeprecationWarning !==
-              true) ||
-          typeof instance.UNSAFE_componentWillMount === 'function';
-        const definesWillReceiveProps =
-          (typeof instance.componentWillReceiveProps === 'function' &&
-            instance.componentWillReceiveProps.__suppressDeprecationWarning !==
-              true) ||
-          typeof instance.UNSAFE_componentWillReceiveProps === 'function';
-        const definesWillUpdate =
-          typeof instance.componentWillUpdate === 'function' ||
-          typeof instance.UNSAFE_componentWillUpdate === 'function';
-
-        if (definesWillMount || definesWillReceiveProps || definesWillUpdate) {
+        let willMount = null;
+        let willReceiveProps = null;
+        let willUpdate = null;
+        if (
+          typeof instance.componentWillMount === 'function' &&
+          instance.componentWillMount.__suppressDeprecationWarning !== true
+        ) {
+          willMount = 'componentWillMount';
+        } else if (typeof instance.UNSAFE_componentWillMount === 'function') {
+          willMount = 'UNSAFE_componentWillMount';
+        }
+        if (
+          typeof instance.componentWillReceiveProps === 'function' &&
+          instance.componentWillReceiveProps.__suppressDeprecationWarning !==
+            true
+        ) {
+          willReceiveProps = 'componentWillReceiveProps';
+        } else if (
+          typeof instance.UNSAFE_componentWillReceiveProps === 'function'
+        ) {
+          willReceiveProps = 'UNSAFE_componentWillReceiveProps';
+        }
+        if (typeof instance.componentWillUpdate === 'function') {
+          willUpdate = 'componentWillUpdate';
+        } else if (typeof instance.UNSAFE_componentWillUpdate === 'function') {
+          willUpdate = 'UNSAFE_componentWillUpdate';
+        }
+        if (
+          willMount !== null ||
+          willReceiveProps !== null ||
+          willUpdate !== null
+        ) {
           const componentName = getName(type, instance) || 'Component';
           if (!didWarnAboutLegacyLifecyclesAndDerivedState[componentName]) {
             warning(
@@ -383,9 +400,9 @@ class ReactShallowRenderer {
                 'The above lifecycles should be removed. Learn more about this warning here:\n' +
                 'https://fb.me/react-async-component-lifecycle-hooks',
               componentName,
-              definesWillMount ? '\n  componentWillMount' : '',
-              definesWillReceiveProps ? '\n  componentWillReceiveProps' : '',
-              definesWillUpdate ? '\n  componentWillUpdate' : '',
+              willMount !== null ? `\n  ${willMount}` : '',
+              willReceiveProps !== null ? `\n  ${willReceiveProps}` : '',
+              willUpdate !== null ? `\n  ${willUpdate}` : '',
             );
             didWarnAboutLegacyLifecyclesAndDerivedState[componentName] = true;
           }
diff --git a/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js b/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
index e161291727d..287394290b3 100644
--- a/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
+++ b/packages/react-test-renderer/src/__tests__/ReactShallowRenderer-test.js
@@ -139,7 +139,7 @@ describe('ReactShallowRenderer', () => {
         return null;
       }
       componentWillMount() {}
-      componentWillReceiveProps() {}
+      UNSAFE_componentWillReceiveProps() {}
       componentWillUpdate() {}
       render() {
         return null;
@@ -151,7 +151,7 @@ describe('ReactShallowRenderer', () => {
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'AllLegacyLifecycles uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
-        '  componentWillReceiveProps\n' +
+        '  UNSAFE_componentWillReceiveProps\n' +
         '  componentWillUpdate\n\n' +
         'The above lifecycles should be removed. Learn more about this warning here:\n' +
         'https://fb.me/react-async-component-lifecycle-hooks',
@@ -162,7 +162,7 @@ describe('ReactShallowRenderer', () => {
       static getDerivedStateFromProps() {
         return null;
       }
-      componentWillMount() {}
+      UNSAFE_componentWillMount() {}
       render() {
         return null;
       }
@@ -172,7 +172,7 @@ describe('ReactShallowRenderer', () => {
     expect(() => shallowRenderer.render(<WillMount />)).toWarnDev(
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillMount uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
-        '  componentWillMount\n\n' +
+        '  UNSAFE_componentWillMount\n\n' +
         'The above lifecycles should be removed. Learn more about this warning here:\n' +
         'https://fb.me/react-async-component-lifecycle-hooks',
     );
@@ -183,7 +183,7 @@ describe('ReactShallowRenderer', () => {
         return null;
       }
       componentWillMount() {}
-      componentWillUpdate() {}
+      UNSAFE_componentWillUpdate() {}
       render() {
         return null;
       }
@@ -194,7 +194,7 @@ describe('ReactShallowRenderer', () => {
       'Unsafe legacy lifecycles will not be called for components using the new getDerivedStateFromProps() API.\n\n' +
         'WillMountAndUpdate uses getDerivedStateFromProps() but also contains the following legacy lifecycles:\n' +
         '  componentWillMount\n' +
-        '  componentWillUpdate\n\n' +
+        '  UNSAFE_componentWillUpdate\n\n' +
         'The above lifecycles should be removed. Learn more about this warning here:\n' +
         'https://fb.me/react-async-component-lifecycle-hooks',
     );

From 9a41ac40c6b0716f731d8e14b1b8cbd8c14edf41 Mon Sep 17 00:00:00 2001
From: Brian Vaughn <brian.david.vaughn@gmail.com>
Date: Thu, 22 Mar 2018 11:03:57 -0700
Subject: [PATCH 5/5] Variable naming nit

---
 .../src/ReactFiberClassComponent.js           | 32 ++++++++++---------
 .../src/ReactShallowRenderer.js               | 32 ++++++++++---------
 2 files changed, 34 insertions(+), 30 deletions(-)

diff --git a/packages/react-reconciler/src/ReactFiberClassComponent.js b/packages/react-reconciler/src/ReactFiberClassComponent.js
index 5240f16b736..8cf9c376769 100644
--- a/packages/react-reconciler/src/ReactFiberClassComponent.js
+++ b/packages/react-reconciler/src/ReactFiberClassComponent.js
@@ -437,37 +437,37 @@ export default function(
         // If getDerivedStateFromProps() is defined, "unsafe" lifecycles won't be called.
         // Warn about these lifecycles if they are present.
         // Don't warn about react-lifecycles-compat polyfilled methods though.
-        let willMount = null;
-        let willReceiveProps = null;
-        let willUpdate = null;
+        let foundWillMountName = null;
+        let foundWillReceivePropsName = null;
+        let foundWillUpdateName = null;
         if (
           typeof instance.componentWillMount === 'function' &&
           instance.componentWillMount.__suppressDeprecationWarning !== true
         ) {
-          willMount = 'componentWillMount';
+          foundWillMountName = 'componentWillMount';
         } else if (typeof instance.UNSAFE_componentWillMount === 'function') {
-          willMount = 'UNSAFE_componentWillMount';
+          foundWillMountName = 'UNSAFE_componentWillMount';
         }
         if (
           typeof instance.componentWillReceiveProps === 'function' &&
           instance.componentWillReceiveProps.__suppressDeprecationWarning !==
             true
         ) {
-          willReceiveProps = 'componentWillReceiveProps';
+          foundWillReceivePropsName = 'componentWillReceiveProps';
         } else if (
           typeof instance.UNSAFE_componentWillReceiveProps === 'function'
         ) {
-          willReceiveProps = 'UNSAFE_componentWillReceiveProps';
+          foundWillReceivePropsName = 'UNSAFE_componentWillReceiveProps';
         }
         if (typeof instance.componentWillUpdate === 'function') {
-          willUpdate = 'componentWillUpdate';
+          foundWillUpdateName = 'componentWillUpdate';
         } else if (typeof instance.UNSAFE_componentWillUpdate === 'function') {
-          willUpdate = 'UNSAFE_componentWillUpdate';
+          foundWillUpdateName = 'UNSAFE_componentWillUpdate';
         }
         if (
-          willMount !== null ||
-          willReceiveProps !== null ||
-          willUpdate !== null
+          foundWillMountName !== null ||
+          foundWillReceivePropsName !== null ||
+          foundWillUpdateName !== null
         ) {
           const componentName = getComponentName(workInProgress) || 'Component';
           if (!didWarnAboutLegacyLifecyclesAndDerivedState[componentName]) {
@@ -480,9 +480,11 @@ export default function(
                 'The above lifecycles should be removed. Learn more about this warning here:\n' +
                 'https://fb.me/react-async-component-lifecycle-hooks',
               componentName,
-              willMount !== null ? `\n  ${willMount}` : '',
-              willReceiveProps !== null ? `\n  ${willReceiveProps}` : '',
-              willUpdate !== null ? `\n  ${willUpdate}` : '',
+              foundWillMountName !== null ? `\n  ${foundWillMountName}` : '',
+              foundWillReceivePropsName !== null
+                ? `\n  ${foundWillReceivePropsName}`
+                : '',
+              foundWillUpdateName !== null ? `\n  ${foundWillUpdateName}` : '',
             );
             didWarnAboutLegacyLifecyclesAndDerivedState[componentName] = true;
           }
diff --git a/packages/react-test-renderer/src/ReactShallowRenderer.js b/packages/react-test-renderer/src/ReactShallowRenderer.js
index 9dc7b5d2cbd..215f5b94d60 100644
--- a/packages/react-test-renderer/src/ReactShallowRenderer.js
+++ b/packages/react-test-renderer/src/ReactShallowRenderer.js
@@ -357,37 +357,37 @@ class ReactShallowRenderer {
         // If getDerivedStateFromProps() is defined, "unsafe" lifecycles won't be called.
         // Warn about these lifecycles if they are present.
         // Don't warn about react-lifecycles-compat polyfilled methods though.
-        let willMount = null;
-        let willReceiveProps = null;
-        let willUpdate = null;
+        let foundWillMountName = null;
+        let foundWillReceivePropsName = null;
+        let foundWillUpdateName = null;
         if (
           typeof instance.componentWillMount === 'function' &&
           instance.componentWillMount.__suppressDeprecationWarning !== true
         ) {
-          willMount = 'componentWillMount';
+          foundWillMountName = 'componentWillMount';
         } else if (typeof instance.UNSAFE_componentWillMount === 'function') {
-          willMount = 'UNSAFE_componentWillMount';
+          foundWillMountName = 'UNSAFE_componentWillMount';
         }
         if (
           typeof instance.componentWillReceiveProps === 'function' &&
           instance.componentWillReceiveProps.__suppressDeprecationWarning !==
             true
         ) {
-          willReceiveProps = 'componentWillReceiveProps';
+          foundWillReceivePropsName = 'componentWillReceiveProps';
         } else if (
           typeof instance.UNSAFE_componentWillReceiveProps === 'function'
         ) {
-          willReceiveProps = 'UNSAFE_componentWillReceiveProps';
+          foundWillReceivePropsName = 'UNSAFE_componentWillReceiveProps';
         }
         if (typeof instance.componentWillUpdate === 'function') {
-          willUpdate = 'componentWillUpdate';
+          foundWillUpdateName = 'componentWillUpdate';
         } else if (typeof instance.UNSAFE_componentWillUpdate === 'function') {
-          willUpdate = 'UNSAFE_componentWillUpdate';
+          foundWillUpdateName = 'UNSAFE_componentWillUpdate';
         }
         if (
-          willMount !== null ||
-          willReceiveProps !== null ||
-          willUpdate !== null
+          foundWillMountName !== null ||
+          foundWillReceivePropsName !== null ||
+          foundWillUpdateName !== null
         ) {
           const componentName = getName(type, instance) || 'Component';
           if (!didWarnAboutLegacyLifecyclesAndDerivedState[componentName]) {
@@ -400,9 +400,11 @@ class ReactShallowRenderer {
                 'The above lifecycles should be removed. Learn more about this warning here:\n' +
                 'https://fb.me/react-async-component-lifecycle-hooks',
               componentName,
-              willMount !== null ? `\n  ${willMount}` : '',
-              willReceiveProps !== null ? `\n  ${willReceiveProps}` : '',
-              willUpdate !== null ? `\n  ${willUpdate}` : '',
+              foundWillMountName !== null ? `\n  ${foundWillMountName}` : '',
+              foundWillReceivePropsName !== null
+                ? `\n  ${foundWillReceivePropsName}`
+                : '',
+              foundWillUpdateName !== null ? `\n  ${foundWillUpdateName}` : '',
             );
             didWarnAboutLegacyLifecyclesAndDerivedState[componentName] = true;
           }