From 0f34b19f0bb6c115a7be3de39f28864292b5da45 Mon Sep 17 00:00:00 2001
From: Nikolay <halt.hammerzeit.at@gmail.com>
Date: Fri, 22 Jul 2016 15:10:45 +0300
Subject: [PATCH] Better debugging of `Expected props argument to be a plain
 object`

---
 src/isomorphic/classic/element/ReactElement.js | 18 ++++++++++--------
 .../element/__tests__/ReactElement-test.js     |  3 ++-
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/src/isomorphic/classic/element/ReactElement.js b/src/isomorphic/classic/element/ReactElement.js
index 710bcaa532546..68df337dc37d1 100644
--- a/src/isomorphic/classic/element/ReactElement.js
+++ b/src/isomorphic/classic/element/ReactElement.js
@@ -167,8 +167,8 @@ ReactElement.createElement = function(type, config, children) {
         /* eslint-disable no-proto */
         config.__proto__ == null || config.__proto__ === Object.prototype,
         /* eslint-enable no-proto */
-        'React.createElement(...): Expected props argument to be a plain object. ' +
-        'Properties defined in its prototype chain will be ignored.'
+        'React.createElement(...): Expected props argument of ' + displayName(type) +
+        ' to be a plain object. Properties defined in its prototype chain will be ignored.'
       );
     }
 
@@ -213,10 +213,6 @@ ReactElement.createElement = function(type, config, children) {
     }
   }
   if (__DEV__) {
-    var displayName = typeof type === 'function' ?
-      (type.displayName || type.name || 'Unknown') :
-      type;
-
     // Create dummy `key` and `ref` property to `props` to warn users against its use
     var warnAboutAccessingKey = function() {
       if (!specialPropKeyWarningShown) {
@@ -227,7 +223,7 @@ ReactElement.createElement = function(type, config, children) {
           'in `undefined` being returned. If you need to access the same ' +
           'value within the child component, you should pass it as a different ' +
           'prop. (https://fb.me/react-special-props)',
-          displayName
+          displayName(type)
         );
       }
       return undefined;
@@ -243,7 +239,7 @@ ReactElement.createElement = function(type, config, children) {
           'in `undefined` being returned. If you need to access the same ' +
           'value within the child component, you should pass it as a different ' +
           'prop. (https://fb.me/react-special-props)',
-          displayName
+          displayName(type)
         );
       }
       return undefined;
@@ -408,4 +404,10 @@ ReactElement.isValidElement = function(object) {
 
 ReactElement.REACT_ELEMENT_TYPE = REACT_ELEMENT_TYPE;
 
+function displayName(type) {
+  return typeof type === 'function' ?
+    (type.displayName || type.name || 'ReactElement') :
+    type;
+}
+
 module.exports = ReactElement;
diff --git a/src/isomorphic/classic/element/__tests__/ReactElement-test.js b/src/isomorphic/classic/element/__tests__/ReactElement-test.js
index 353989ad6b089..008eeba0535f2 100644
--- a/src/isomorphic/classic/element/__tests__/ReactElement-test.js
+++ b/src/isomorphic/classic/element/__tests__/ReactElement-test.js
@@ -195,7 +195,8 @@ describe('ReactElement', function() {
     React.createElement('div', Object.create({foo: 1}));
     expect(console.error.calls.count()).toBe(1);
     expect(console.error.calls.argsFor(0)[0]).toContain(
-      'React.createElement(...): Expected props argument to be a plain object. ' +
+      'React.createElement(...): Expected props argument of div ' +
+      'to be a plain object. ' +
       'Properties defined in its prototype chain will be ignored.'
     );
   });