From ea416933e3442789ab76e132388f1f4ca3a55cb8 Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Tue, 3 Jan 2017 15:15:55 -0500
Subject: [PATCH 01/13] Added _state abstraction

---
 agent/Bridge.js | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/agent/Bridge.js b/agent/Bridge.js
index db41f48288..18b2e6e1b2 100644
--- a/agent/Bridge.js
+++ b/agent/Bridge.js
@@ -403,16 +403,20 @@ class Bridge {
     var protoclean = [];
     if (inspectable) {
       var val = getIn(inspectable, path);
+
+
       var protod = false;
       var isFn = typeof val === 'function';
-      Object.getOwnPropertyNames(val).forEach(name => {
+      var data = val._state || val;
+
+      Object.getOwnPropertyNames( data ).forEach(name => {
         if (name === '__proto__') {
           protod = true;
         }
         if (isFn && (name === 'arguments' || name === 'callee' || name === 'caller')) {
           return;
         }
-        result[name] = dehydrate(val[name], cleaned, [name]);
+        result[name] = dehydrate( data[name], cleaned, [name]);
       });
 
       /* eslint-disable no-proto */
@@ -420,10 +424,13 @@ class Bridge {
         var newProto = {};
         var pIsFn = typeof val.__proto__ === 'function';
         Object.getOwnPropertyNames(val.__proto__).forEach(name => {
-          if (pIsFn && (name === 'arguments' || name === 'callee' || name === 'caller')) {
+          if( pIsFn && (name === 'arguments' || name === 'callee' || name === 'caller') ){
             return;
           }
-          newProto[name] = dehydrate(val.__proto__[name], protoclean, [name]);
+
+          var prop = Object.getOwnPropertyDescriptor( val.__proto__, name );
+
+          newProto[name] = dehydrate( prop.get ? prop.get : val.__proto__[name], protoclean, [name]);
         });
         proto = newProto;
       }
@@ -440,7 +447,7 @@ class Bridge {
 
 function getIn(base, path) {
   return path.reduce((obj, attr) => {
-    return obj ? obj[attr] : null;
+    return obj ? ( ( obj._state || obj )[ attr ] ): null;
   }, base);
 }
 

From a3cd3d7bb26ddb2322ecedbb52e8b0d0d34803ab Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Tue, 3 Jan 2017 18:52:21 -0500
Subject: [PATCH 02/13] Fixed state and props for NestedReact

---
 agent/Bridge.js    | 20 ++++++++++++--------
 agent/dehydrate.js |  4 ++++
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/agent/Bridge.js b/agent/Bridge.js
index 18b2e6e1b2..885d3499b9 100644
--- a/agent/Bridge.js
+++ b/agent/Bridge.js
@@ -404,23 +404,27 @@ class Bridge {
     if (inspectable) {
       var val = getIn(inspectable, path);
 
-
-      var protod = false;
+      var protod = false, isWrapper = false;
       var isFn = typeof val === 'function';
-      var data = val._state || val;
 
-      Object.getOwnPropertyNames( data ).forEach(name => {
-        if (name === '__proto__') {
+      if( val && val._state ){
+          val = val._state;
+          isWrapper = true;
+      }
+
+      Object.getOwnPropertyNames( val ).forEach(name => {
+        if (name === '__proto__' && !isWrapper ) {
           protod = true;
         }
+
         if (isFn && (name === 'arguments' || name === 'callee' || name === 'caller')) {
           return;
         }
-        result[name] = dehydrate( data[name], cleaned, [name]);
+        result[name] = dehydrate( val[name], cleaned, [name]);
       });
 
       /* eslint-disable no-proto */
-      if (!protod && val.__proto__ && val.constructor.name !== 'Object') {
+      if (!protod && val.__proto__ && val.constructor.name !== 'Object' && !isWrapper ) {
         var newProto = {};
         var pIsFn = typeof val.__proto__ === 'function';
         Object.getOwnPropertyNames(val.__proto__).forEach(name => {
@@ -447,7 +451,7 @@ class Bridge {
 
 function getIn(base, path) {
   return path.reduce((obj, attr) => {
-    return obj ? ( ( obj._state || obj )[ attr ] ): null;
+    return obj ? ( ( obj._state || obj : obj )[ attr ] ): null;
   }, base);
 }
 
diff --git a/agent/dehydrate.js b/agent/dehydrate.js
index 0fddfac5a1..236c8a7746 100644
--- a/agent/dehydrate.js
+++ b/agent/dehydrate.js
@@ -31,6 +31,10 @@
  * and cleaned = [["some", "attr"], ["other"]]
  */
 function dehydrate(data: Object, cleaned: Array<Array<string>>, path?: Array<string>, level?: number): string | Object {
+  if( data && data._state && path[ path.length - 1 ] === 'state' ){
+    data = data._state;
+  }
+
   level = level || 0;
   path = path || [];
   if (typeof data === 'function') {

From 1b9c40eaaf6d818cc6bf9f2f282feac9661606c3 Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Wed, 4 Jan 2017 20:55:11 -0500
Subject: [PATCH 03/13] - Show prototype for objects with inner state - Do not
 call calculated properties on prototype chain

---
 agent/Bridge.js    | 36 ++++++++++++++++++++++++++----------
 agent/dehydrate.js |  5 +++--
 2 files changed, 29 insertions(+), 12 deletions(-)

diff --git a/agent/Bridge.js b/agent/Bridge.js
index 885d3499b9..40b3ed4cbf 100644
--- a/agent/Bridge.js
+++ b/agent/Bridge.js
@@ -404,27 +404,25 @@ class Bridge {
     if (inspectable) {
       var val = getIn(inspectable, path);
 
-      var protod = false, isWrapper = false;
+      var protod = false;
       var isFn = typeof val === 'function';
 
-      if( val && val._state ){
-          val = val._state;
-          isWrapper = true;
-      }
+      // Extract inner state of the third-party frameworks data objects...
+      var source = ( val && val._innerState ) || val;
 
-      Object.getOwnPropertyNames( val ).forEach(name => {
-        if (name === '__proto__' && !isWrapper ) {
+      Object.getOwnPropertyNames( source ).forEach(name => {
+        if (name === '__proto__' ) {
           protod = true;
         }
 
         if (isFn && (name === 'arguments' || name === 'callee' || name === 'caller')) {
           return;
         }
-        result[name] = dehydrate( val[name], cleaned, [name]);
+        result[name] = dehydrate( source[name], cleaned, [name]);
       });
 
       /* eslint-disable no-proto */
-      if (!protod && val.__proto__ && val.constructor.name !== 'Object' && !isWrapper ) {
+      if (!protod && val.__proto__ && val.constructor.name !== 'Object' ) {
         var newProto = {};
         var pIsFn = typeof val.__proto__ === 'function';
         Object.getOwnPropertyNames(val.__proto__).forEach(name => {
@@ -432,6 +430,7 @@ class Bridge {
             return;
           }
 
+          // Calculated properties should not be evaluated on prototype.
           var prop = Object.getOwnPropertyDescriptor( val.__proto__, name );
 
           newProto[name] = dehydrate( prop.get ? prop.get : val.__proto__[name], protoclean, [name]);
@@ -450,8 +449,25 @@ class Bridge {
 }
 
 function getIn(base, path) {
+  let isPrototypeChain = false;
+
   return path.reduce((obj, attr) => {
-    return obj ? ( ( obj._state || obj : obj )[ attr ] ): null;
+    if( !obj ) return null;
+
+    // Mark the beginning of the prototype chain...
+    if( attr === "__proto__" ){
+      isPrototypeChain = true;
+      return obj.__proto__;
+    }
+
+    if( isPrototypeChain ){
+      // Avoid calling calculated properties on prototype.
+      const property = Object.getOwnPropertyDescriptor( obj, attr );
+      return property.get || property.value;
+    }
+
+    // Traverse inner state of the third-party data frameworks objects...
+    return ( obj._innerState || obj )[ attr ];
   }, base);
 }
 
diff --git a/agent/dehydrate.js b/agent/dehydrate.js
index 236c8a7746..30df73a1c8 100644
--- a/agent/dehydrate.js
+++ b/agent/dehydrate.js
@@ -31,8 +31,9 @@
  * and cleaned = [["some", "attr"], ["other"]]
  */
 function dehydrate(data: Object, cleaned: Array<Array<string>>, path?: Array<string>, level?: number): string | Object {
-  if( data && data._state && path[ path.length - 1 ] === 'state' ){
-    data = data._state;
+  // Support third-party frameworks data objects in react component state.
+  if( data && data._innerState && path[ path.length - 1 ] === 'state' ){
+    data = data._innerState;
   }
 
   level = level || 0;

From f0310a5f5f227e7a4899b798a003610d30c47f3f Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Wed, 4 Jan 2017 21:02:03 -0500
Subject: [PATCH 04/13] Fixed lint errors

---
 agent/Bridge.js    | 14 ++++++++------
 agent/dehydrate.js |  2 +-
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/agent/Bridge.js b/agent/Bridge.js
index 40b3ed4cbf..168d4386b3 100644
--- a/agent/Bridge.js
+++ b/agent/Bridge.js
@@ -426,7 +426,7 @@ class Bridge {
         var newProto = {};
         var pIsFn = typeof val.__proto__ === 'function';
         Object.getOwnPropertyNames(val.__proto__).forEach(name => {
-          if( pIsFn && (name === 'arguments' || name === 'callee' || name === 'caller') ){
+          if (pIsFn && (name === 'arguments' || name === 'callee' || name === 'caller') ) {
             return;
           }
 
@@ -452,22 +452,24 @@ function getIn(base, path) {
   let isPrototypeChain = false;
 
   return path.reduce((obj, attr) => {
-    if( !obj ) return null;
+    if (!obj) {
+      return null;
+    }
 
     // Mark the beginning of the prototype chain...
-    if( attr === "__proto__" ){
+    if (attr === '__proto__') {
       isPrototypeChain = true;
-      return obj.__proto__;
+      return obj[attr];
     }
 
-    if( isPrototypeChain ){
+    if (isPrototypeChain) {
       // Avoid calling calculated properties on prototype.
       const property = Object.getOwnPropertyDescriptor( obj, attr );
       return property.get || property.value;
     }
 
     // Traverse inner state of the third-party data frameworks objects...
-    return ( obj._innerState || obj )[ attr ];
+    return ( obj._innerState || obj )[attr];
   }, base);
 }
 
diff --git a/agent/dehydrate.js b/agent/dehydrate.js
index 30df73a1c8..860e49613c 100644
--- a/agent/dehydrate.js
+++ b/agent/dehydrate.js
@@ -32,7 +32,7 @@
  */
 function dehydrate(data: Object, cleaned: Array<Array<string>>, path?: Array<string>, level?: number): string | Object {
   // Support third-party frameworks data objects in react component state.
-  if( data && data._innerState && path[ path.length - 1 ] === 'state' ){
+  if (data && data._innerState && path[path.length - 1] === 'state') {
     data = data._innerState;
   }
 

From d1473cbe4c6d185b26a25a6e75d5da8c3d1ddfa3 Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Wed, 4 Jan 2017 21:56:53 -0500
Subject: [PATCH 05/13] Fixed flow type error

---
 agent/dehydrate.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/agent/dehydrate.js b/agent/dehydrate.js
index 860e49613c..23501acc2a 100644
--- a/agent/dehydrate.js
+++ b/agent/dehydrate.js
@@ -32,7 +32,7 @@
  */
 function dehydrate(data: Object, cleaned: Array<Array<string>>, path?: Array<string>, level?: number): string | Object {
   // Support third-party frameworks data objects in react component state.
-  if (data && data._innerState && path[path.length - 1] === 'state') {
+  if (data && data._innerState && path && path[path.length - 1] === 'state') {
     data = data._innerState;
   }
 

From fb7b03dbbb5408227c88dfe2996f5487ea339c80 Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Thu, 5 Jan 2017 19:01:09 -0500
Subject: [PATCH 06/13] renamed _innerState to avoid potential name collisions.

---
 agent/Bridge.js    | 2 --
 agent/dehydrate.js | 2 --
 2 files changed, 4 deletions(-)

diff --git a/agent/Bridge.js b/agent/Bridge.js
index 168d4386b3..aca9779085 100644
--- a/agent/Bridge.js
+++ b/agent/Bridge.js
@@ -408,7 +408,6 @@ class Bridge {
       var isFn = typeof val === 'function';
 
       // Extract inner state of the third-party frameworks data objects...
-      var source = ( val && val._innerState ) || val;
 
       Object.getOwnPropertyNames( source ).forEach(name => {
         if (name === '__proto__' ) {
@@ -469,7 +468,6 @@ function getIn(base, path) {
     }
 
     // Traverse inner state of the third-party data frameworks objects...
-    return ( obj._innerState || obj )[attr];
   }, base);
 }
 
diff --git a/agent/dehydrate.js b/agent/dehydrate.js
index 23501acc2a..9601075138 100644
--- a/agent/dehydrate.js
+++ b/agent/dehydrate.js
@@ -32,8 +32,6 @@
  */
 function dehydrate(data: Object, cleaned: Array<Array<string>>, path?: Array<string>, level?: number): string | Object {
   // Support third-party frameworks data objects in react component state.
-  if (data && data._innerState && path && path[path.length - 1] === 'state') {
-    data = data._innerState;
   }
 
   level = level || 0;

From 25bdd33d4457977f42b6690d44d147bd7fba04d4 Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Thu, 5 Jan 2017 19:02:18 -0500
Subject: [PATCH 07/13] fixed commit error

---
 agent/Bridge.js    | 2 ++
 agent/dehydrate.js | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/agent/Bridge.js b/agent/Bridge.js
index aca9779085..7b8be3029d 100644
--- a/agent/Bridge.js
+++ b/agent/Bridge.js
@@ -408,6 +408,7 @@ class Bridge {
       var isFn = typeof val === 'function';
 
       // Extract inner state of the third-party frameworks data objects...
+      var source = ( val && val.__inner_state__ ) || val;
 
       Object.getOwnPropertyNames( source ).forEach(name => {
         if (name === '__proto__' ) {
@@ -468,6 +469,7 @@ function getIn(base, path) {
     }
 
     // Traverse inner state of the third-party data frameworks objects...
+    return ( obj.__inner_state__ || obj )[attr];
   }, base);
 }
 
diff --git a/agent/dehydrate.js b/agent/dehydrate.js
index 9601075138..b68e784207 100644
--- a/agent/dehydrate.js
+++ b/agent/dehydrate.js
@@ -32,6 +32,8 @@
  */
 function dehydrate(data: Object, cleaned: Array<Array<string>>, path?: Array<string>, level?: number): string | Object {
   // Support third-party frameworks data objects in react component state.
+  if (data && data.__inner_state__ && path && path[path.length - 1] === 'state') {
+    data = data.__inner_state__;
   }
 
   level = level || 0;

From 6ee5c9dfe6740b7c6f2d451ade6b882e6f42879d Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Thu, 5 Jan 2017 19:19:57 -0500
Subject: [PATCH 08/13] Prevent __inner_state__ from appearing in __proto__

---
 agent/Bridge.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/agent/Bridge.js b/agent/Bridge.js
index 7b8be3029d..9c21b0ef8e 100644
--- a/agent/Bridge.js
+++ b/agent/Bridge.js
@@ -426,7 +426,7 @@ class Bridge {
         var newProto = {};
         var pIsFn = typeof val.__proto__ === 'function';
         Object.getOwnPropertyNames(val.__proto__).forEach(name => {
-          if (pIsFn && (name === 'arguments' || name === 'callee' || name === 'caller') ) {
+          if ( name === '__inner_state__' || ( pIsFn && (name === 'arguments' || name === 'callee' || name === 'caller') ) ) {
             return;
           }
 

From bf0c893a8fad9acc609e771d94728a8fe2588705 Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Thu, 5 Jan 2017 19:50:31 -0500
Subject: [PATCH 09/13] Implemented addInnerStateInspector hook API

---
 agent/Agent.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/agent/Agent.js b/agent/Agent.js
index 2602f8505c..3dc966170f 100644
--- a/agent/Agent.js
+++ b/agent/Agent.js
@@ -410,4 +410,14 @@ function getIn(base, path) {
   }, base);
 }
 
+function addInnerStateInspector(Ctor, getInnerState) {
+  Object.defineProperty( Ctor.prototype, '__inner_state__', {
+    get : function() {
+      return getInnerState( this );
+    },
+  });
+}
+
+window.__REACT_DEVTOOLS_GLOBAL_HOOK__.addInnerStateInspector = addInnerStateInspector;
+
 module.exports = Agent;

From bf581d677f3bcd4c504e8822164e6d3241289bd5 Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Thu, 5 Jan 2017 20:15:01 -0500
Subject: [PATCH 10/13] Fixed implementation of global hook

---
 agent/Agent.js               | 10 ----------
 backend/installGlobalHook.js |  9 ++++++++-
 backend/types.js             |  2 ++
 3 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/agent/Agent.js b/agent/Agent.js
index 3dc966170f..2602f8505c 100644
--- a/agent/Agent.js
+++ b/agent/Agent.js
@@ -410,14 +410,4 @@ function getIn(base, path) {
   }, base);
 }
 
-function addInnerStateInspector(Ctor, getInnerState) {
-  Object.defineProperty( Ctor.prototype, '__inner_state__', {
-    get : function() {
-      return getInnerState( this );
-    },
-  });
-}
-
-window.__REACT_DEVTOOLS_GLOBAL_HOOK__.addInnerStateInspector = addInnerStateInspector;
-
 module.exports = Agent;
diff --git a/backend/installGlobalHook.js b/backend/installGlobalHook.js
index a9f0192178..906b93f667 100644
--- a/backend/installGlobalHook.js
+++ b/backend/installGlobalHook.js
@@ -57,7 +57,14 @@ function installGlobalHook(window: Object) {
           this._listeners[evt].map(fn => fn(data));
         }
       },
-    }: Hook),
+      addInnerStateInspector: function(Ctor, getInnerState) {
+        Object.defineProperty( Ctor.prototype, '__inner_state__', {
+            get : function() {
+                return getInnerState( this );
+            },
+        });
+      }
+}: Hook),
   });
 }
 
diff --git a/backend/types.js b/backend/types.js
index 6d0dd5f733..0b3c03e6b4 100644
--- a/backend/types.js
+++ b/backend/types.js
@@ -80,6 +80,7 @@ export type Helpers = {
 };
 
 export type Handler = (data: any) => void;
+export type InnerStateInspector = (data: any) => any;
 
 export type Hook = {
   _renderers: {[key: string]: ReactRenderer},
@@ -91,4 +92,5 @@ export type Hook = {
   on: (evt: string, handler: Handler) => void,
   off: (evt: string, handler: Handler) => void,
   reactDevtoolsAgent?: ?Object,
+  addInnerStateInspector: ( Ctor : Function, handler : InnerStateInspector ) => void;
 };

From 855e9adbb8956185f3f933e54ef60de8034769cf Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Thu, 5 Jan 2017 20:50:59 -0500
Subject: [PATCH 11/13] Fixed flow type errors

---
 backend/installGlobalHook.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/backend/installGlobalHook.js b/backend/installGlobalHook.js
index 906b93f667..5d51aeed0e 100644
--- a/backend/installGlobalHook.js
+++ b/backend/installGlobalHook.js
@@ -58,11 +58,11 @@ function installGlobalHook(window: Object) {
         }
       },
       addInnerStateInspector: function(Ctor, getInnerState) {
-        Object.defineProperty( Ctor.prototype, '__inner_state__', {
+        Object.defineProperty( Ctor.prototype, '__inner_state__', ({
             get : function() {
                 return getInnerState( this );
             },
-        });
+        } : Object ));
       }
 }: Hook),
   });

From 1071583cd841315d2baeec39a056db1ff5c7c3d9 Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Thu, 5 Jan 2017 21:06:50 -0500
Subject: [PATCH 12/13] Fixed lint errors

---
 backend/installGlobalHook.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/backend/installGlobalHook.js b/backend/installGlobalHook.js
index 5d51aeed0e..796d4eafaa 100644
--- a/backend/installGlobalHook.js
+++ b/backend/installGlobalHook.js
@@ -59,12 +59,12 @@ function installGlobalHook(window: Object) {
       },
       addInnerStateInspector: function(Ctor, getInnerState) {
         Object.defineProperty( Ctor.prototype, '__inner_state__', ({
-            get : function() {
-                return getInnerState( this );
-            },
+          get : function() {
+            return getInnerState( this );
+          },
         } : Object ));
-      }
-}: Hook),
+      },
+    }: Hook),
   });
 }
 

From bfce3b6722c65cc4837628a1443023415add2d1a Mon Sep 17 00:00:00 2001
From: Vlad Balin <gaperton@gmail.com>
Date: Fri, 6 Jan 2017 17:13:47 -0500
Subject: [PATCH 13/13] Added Date inner state inspector

---
 backend/backend.js              |  3 +++
 backend/innerStateInspectors.js | 18 ++++++++++++++++++
 backend/installGlobalHook.js    | 16 ++++++++++------
 backend/types.js                |  2 +-
 4 files changed, 32 insertions(+), 7 deletions(-)
 create mode 100644 backend/innerStateInspectors.js

diff --git a/backend/backend.js b/backend/backend.js
index ff64a5ccd9..92f555f692 100644
--- a/backend/backend.js
+++ b/backend/backend.js
@@ -24,10 +24,13 @@
 'use strict';
 
 import type {Hook} from './types';
+import attachInnerStateInspectors from './innerStateInspectors';
 
 var attachRenderer = require('./attachRenderer');
 
 module.exports = function setupBackend(hook: Hook): boolean {
+  attachInnerStateInspectors( hook );
+
   var oldReact = window.React && window.React.__internals;
   if (oldReact && Object.keys(hook._renderers).length === 0) {
     hook.inject(oldReact);
diff --git a/backend/innerStateInspectors.js b/backend/innerStateInspectors.js
new file mode 100644
index 0000000000..cfbfc1ce34
--- /dev/null
+++ b/backend/innerStateInspectors.js
@@ -0,0 +1,18 @@
+/**
+ * @flow
+ *
+ * Inner state inspectors for the built in JS data types.
+ */
+
+'use strict';
+
+import type {Hook} from './types';
+
+export default
+function attachInnerStateInspectors({ addInnerStateInspector } : Hook ) {
+  addInnerStateInspector( Date, ( x : Date ) => ({
+    local : `${ x.toDateString() } ${ x.toTimeString() }`,
+    iso : x.toISOString(),
+    timestamp : x.getTime(),
+  }), true );
+}
diff --git a/backend/installGlobalHook.js b/backend/installGlobalHook.js
index 796d4eafaa..fd37130f13 100644
--- a/backend/installGlobalHook.js
+++ b/backend/installGlobalHook.js
@@ -57,12 +57,16 @@ function installGlobalHook(window: Object) {
           this._listeners[evt].map(fn => fn(data));
         }
       },
-      addInnerStateInspector: function(Ctor, getInnerState) {
-        Object.defineProperty( Ctor.prototype, '__inner_state__', ({
-          get : function() {
-            return getInnerState( this );
-          },
-        } : Object ));
+      addInnerStateInspector: function(Ctor, getInnerState, skipIfDefined) {
+        if ( !( skipIfDefined && Ctor.prototype.hasOwnProperty( '__inner_state__' ) ) ) {
+          Object.defineProperty(Ctor.prototype, '__inner_state__', ({
+            get: function() {
+              return getInnerState(this);
+            },
+            enumerable: false,
+            configurable: true,
+          } : Object ));
+        }
       },
     }: Hook),
   });
diff --git a/backend/types.js b/backend/types.js
index 0b3c03e6b4..cb497db6bd 100644
--- a/backend/types.js
+++ b/backend/types.js
@@ -92,5 +92,5 @@ export type Hook = {
   on: (evt: string, handler: Handler) => void,
   off: (evt: string, handler: Handler) => void,
   reactDevtoolsAgent?: ?Object,
-  addInnerStateInspector: ( Ctor : Function, handler : InnerStateInspector ) => void;
+  addInnerStateInspector: ( Ctor : Function, handler : InnerStateInspector, skipIfDefined? : boolean ) => void;
 };