Fix obscure error message when passing an invalid style value for SSR

[iamdustan]

This may be a regression to add to #11065.

Adding a reduced test case for this issue by opening a PR. When trying to server render an iframe with an invalid style tag the following error is thrown:

~/react/ssr-test/node_modules/react-dom/cjs/react-dom-server.node.development.js:651                                                                                                                            var ownerName = getCurrentOwnerName();
                                                                                                                                                                      ^                                                                                                                                                                                                                                                                                                                                                                                                   TypeError: getCurrentOwnerName is not a function                                                                                                                                                               
at getDeclarationErrorAddendum (~/react/ssr-test/node_modules/react-dom/cjs/react-dom-server.node.development.js:651:21)                                                                                   
at assertValidProps (~/react/ssr-test/node_modules/react-dom/cjs/react-dom-server.node.development.js:675:236)                                                                                             
at ReactDOMServerRenderer.renderDOM (~/react/ssr-test/node_modules/react-dom/cjs/react-dom-server.node.development.js:2922:5)                                                                              
at ReactDOMServerRenderer.render (~/react/ssr-test/node_modules/react-dom/cjs/react-dom-server.node.development.js:2755:23)                                                                                
at ReactDOMServerRenderer.read (~/react/ssr-test/node_modules/react-dom/cjs/react-dom-server.node.development.js:2722:19)                                                                                  
at renderToString (~/react/ssr-test/node_modules/react-dom/cjs/react-dom-server.node.development.js:2980:25)                                                                                               
at Object.<anonymous> (~/react/ssr-test/src/Ssr.js:5:3)                                                                                                                                                    
at Module._compile (module.js:570:32)                                                                                                                                                                      
at loader (~/react/ssr-test/node_modules/babel-register/lib/node.js:144:5)                                                                                                                                 
at Object.require.extensions.(anonymous function) [as .js] (~/react/ssr-test/node_modules/babel-register/lib/node.js:154:7) 

I would expect this to throw the invalid props-style warning of:

The `style` prop expects a mapping from style properties to values, not a string. For example, style={{marginRight: spacing + \'em\'}} when using JSX.

This can be traced back to this line here where we are missing the third argument to assertValidProps:

react/src/renderers/shared/server/ReactPartialRenderer.js

Line 783 in a276ffc

assertValidProps(tag, props);

This file is not checked by flow which is possibly how the missed argument slipped through, though naively ading the @flow pragma to that file has 39 errors.

What should the fix be? (I included a commit to implement the only solution I’ve considered thus far)

• Add a noop third argument to checkValidProps? (since the only other owner ref in that file is explicitly set to null at https://github.com/facebook/react/blob/master/src/renderers/shared/server/ReactPartialRenderer.js#L57)
• alternative?

[gaearon]

Can you please declare it in the top scope so we don’t need to worry about allocating?

[gaearon]

You can just pass emptyFunction.thatReturnsNull.

[gaearon]

And yes, we should Flow-ify that file. But that’s a separate problem. Wanna do it in another PR?

[gaearon]

Prettier is failing.

[gaearon]

Prettier is failing.

[gaearon]

Use emptyFunction.thatReturnsNull

[gaearon]

Filed #11175 for Flow.

[iamdustan]

👌 thanks, Dan!

[gaearon]

React 16.1.0-beta has been released. Please update react, react-dom, and react-test-renderer (if you use it) to this version and let us know if it solved the issue! We’d appreciate if you could test before Monday when we plan to get 16.1.0 out.

[ValentinFunk]

Would it be possible for React to throw for invalid styles when inside React.StrictMode?