Fix state not being flushed after cWM

Author: marvinhagemeister

src/index.js

@@ -112,6 +112,13 @@ function renderToString(vnode, context, opts, inner, isSvgMode, selectValue) {
 				c.context = cctx;
 				if (nodeName.getDerivedStateFromProps) c.state = assign(assign({}, c.state), nodeName.getDerivedStateFromProps(c.props, c.state));
 				else if (c.componentWillMount) c.componentWillMount();
+
+				// If the user called setState in cWM we need to flush pending,
+				// state updates. This is the same behaviour in React.
+				c.state = c._nextState !== c.state
+					? c._nextState : c.__s!==c.state
+						? c.__s : c.state;
+
 				rendered = c.render(c.props, c.state, c.context);
 			}
 

test/render.js

@@ -363,7 +363,6 @@ describe('render', () => {
 				componentWillMount() {
 					this.setState({ updated: true });
 				}
-
 				render() {
 					return (
 						<p>
@@ -373,7 +372,7 @@ describe('render', () => {
 				}
 			}
 
-			expect(render(<Test />)).to.equal('<p>false</p>');
+			expect(render(<Test />)).to.equal('<p>true</p>');
 		});
 
 		it('should invoke getDerivedStateFromProps rather than componentWillMount', () => {