Warn when using hyphenated style property names

docs/tips/02-inline-styles.md

@@ -15,10 +15,11 @@ In React, inline styles are not specified as a string. Instead they are specifie
 var divStyle = {
   color: 'white',
   backgroundImage: 'url(' + imgUrl + ')',
-  WebkitTransition: 'all' // note the capital 'W' here
+  WebkitTransition: 'all', // note the capital 'W' here
+  msTransition: 'all' // 'ms' is the only lowercase vendor prefix
 };
 
 React.renderComponent(<div style={divStyle}>Hello World!</div>, mountNode);
 ```
 
-Style keys are camelCased in order to be consistent with accessing the properties on DOM nodes from JS (e.g. `node.style.backgroundImage`). Vendor prefixes should begin with a capital letter. This is why `WebkitTransition` has an uppercase "W".
+Style keys are camelCased in order to be consistent with accessing the properties on DOM nodes from JS (e.g. `node.style.backgroundImage`). Vendor prefixes [other than `ms`](http://www.andismith.com/blog/2012/02/modernizr-prefixed/) should begin with a capital letter. This is why `WebkitTransition` has an uppercase "W".

src/browser/ui/dom/CSSPropertyOperations.js

@@ -21,14 +21,33 @@
 
 var CSSProperty = require('CSSProperty');
 
+var camelizeStyleName = require('camelizeStyleName');
 var dangerousStyleValue = require('dangerousStyleValue');
 var hyphenateStyleName = require('hyphenateStyleName');
 var memoizeStringOnly = require('memoizeStringOnly');
+var warning = require('warning');
 
 var processStyleName = memoizeStringOnly(function(styleName) {
   return hyphenateStyleName(styleName);
 });
 
+if (__DEV__) {
+  var warnedStyleNames = {};
+
+  var warnHyphenatedStyleName = function(name) {
+    if (warnedStyleNames.hasOwnProperty(name) && warnedStyleNames[name]) {
+      return;
+    }
+
+    warnedStyleNames[name] = true;
+    warning(
+      false,
+      'Unsupported style property ' + name + '. Did you mean ' +
+      camelizeStyleName(name) + '?'
+    );
+  };
+}
+
 /**
  * Operations for dealing with CSS properties.
  */
@@ -52,6 +71,11 @@ var CSSPropertyOperations = {
       if (!styles.hasOwnProperty(styleName)) {
         continue;
       }
+      if (__DEV__) {
+        if (styleName.indexOf('-') > -1) {
+          warnHyphenatedStyleName(styleName);
+        }
+      }
       var styleValue = styles[styleName];
       if (styleValue != null) {
         serialized += processStyleName(styleName) + ':';
@@ -74,6 +98,11 @@ var CSSPropertyOperations = {
       if (!styles.hasOwnProperty(styleName)) {
         continue;
       }
+      if (__DEV__) {
+        if (styleName.indexOf('-') > -1) {
+          warnHyphenatedStyleName(styleName);
+        }
+      }
       var styleValue = dangerousStyleValue(styleName, styles[styleName]);
       if (styleValue) {
         style[styleName] = styleValue;

src/browser/ui/dom/__tests__/CSSPropertyOperations-test.js

@@ -108,4 +108,32 @@ describe('CSSPropertyOperations', function() {
     expect(/style=".*"/.test(root.innerHTML)).toBe(false);
   });
 
+  it('should warn when using hyphenated style names', function() {
+    spyOn(console, 'warn');
+
+    expect(CSSPropertyOperations.createMarkupForStyles({
+      'background-color': 'crimson'
+    })).toBe('background-color:crimson;');
+
+    expect(console.warn.argsForCall.length).toBe(1);
+    expect(console.warn.argsForCall[0][0]).toContain('backgroundColor');
+  });
+
+  it('should warn when updating hyphenated style names', function() {
+    spyOn(console, 'warn');
+
+    var root = document.createElement('div');
+    var styles = {
+      '-ms-transform': 'translate3d(0, 0, 0)',
+      '-webkit-transform': 'translate3d(0, 0, 0)'
+    };
+
+    React.renderComponent(<div />, root);
+    React.renderComponent(<div style={styles} />, root);
+
+    expect(console.warn.argsForCall.length).toBe(2);
+    expect(console.warn.argsForCall[0][0]).toContain('msTransform');
+    expect(console.warn.argsForCall[1][0]).toContain('WebkitTransform');
+  });
+
 });

src/vendor/core/camelizeStyleName.js

@@ -0,0 +1,47 @@
+/**
+ * Copyright 2014 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * @providesModule camelizeStyleName
+ * @typechecks
+ */
+
+"use strict";
+
+var camelize = require('camelize');
+
+var msPattern = /^-ms-/;
+
+/**
+ * Camelcases a hyphenated CSS property name, for example:
+ *
+ *   > camelizeStyleName('background-color')
+ *   < "backgroundColor"
+ *   > camelizeStyleName('-moz-transition')
+ *   < "MozTransition"
+ *   > camelizeStyleName('-ms-transition')
+ *   < "msTransition"
+ *
+ * As Andi Smith suggests
+ * (http://www.andismith.com/blog/2012/02/modernizr-prefixed/), an `-ms` prefix
+ * is converted to lowercase `ms`.
+ *
+ * @param {string} string
+ * @return {string}
+ */
+function camelizeStyleName(string) {
+  return camelize(string.replace(msPattern, 'ms-'));
+}
+
+module.exports = camelizeStyleName;

src/vendor/core/hyphenateStyleName.js

@@ -26,11 +26,11 @@ var msPattern = /^ms-/;
 /**
  * Hyphenates a camelcased CSS property name, for example:
  *
- *   > hyphenate('backgroundColor')
+ *   > hyphenateStyleName('backgroundColor')
  *   < "background-color"
- *   > hyphenate('MozTransition')
+ *   > hyphenateStyleName('MozTransition')
  *   < "-moz-transition"
- *   > hyphenate('msTransition')
+ *   > hyphenateStyleName('msTransition')
  *   < "-ms-transition"
  *
  * As Modernizr suggests (http://modernizr.com/docs/#prefixed), an `ms` prefix