[New] render: add support for context

docs/api/render.md

@@ -19,7 +19,6 @@ constructors.
 import { render } from 'enzyme';
 
 describe('<Foo />', () => {
-
   it('renders three `.foo-bar`s', () => {
     const wrapper = render(<Foo />);
     expect(wrapper.find('.foo-bar')).to.have.length(3);
@@ -30,5 +29,19 @@ describe('<Foo />', () => {
     expect(wrapper.text()).to.contain("unique");
   });
 
+  it('can pass in context', () => {
+    const SimpleComponent = React.createClass({
+      contextTypes: {
+        name: React.PropTypes.string,
+      },
+      render() {
+        return <div>{this.context.name}</div>;
+      },
+    });
+
+    const context = { name: 'foo' };
+    const wrapper = render(<SimpleComponent />, { context });
+    expect(wrapper.text()).to.equal('foo');
+  });
 });
 ```

src/render.jsx

@@ -1,3 +1,5 @@
+import React from 'react';
+import objectAssign from 'object.assign';
 import cheerio from 'cheerio';
 import { renderToStaticMarkup } from './react-compat';
 
@@ -11,9 +13,34 @@ import { renderToStaticMarkup } from './react-compat';
  * thus I'd like to keep this API in here even though it's not really "ours".
  *
  * @param node
+ * @param options
  * @returns {Cheerio}
  */
-export default function render(node) {
+
+function createContextWrapperForNode(node, context, childContextTypes) {
+  class ContextWrapper extends React.Component {
+    getChildContext() {
+      return context;
+    }
+    render() {
+      return node;
+    }
+  }
+  ContextWrapper.childContextTypes = childContextTypes;
+  return ContextWrapper;
+}
+
+export default function render(node, options = {}) {
+  if (options.context && (node.type.contextTypes || options.childContextTypes)) {
+    const childContextTypes = objectAssign(
+      {},
+      node.type.contextTypes || {},
+      options.childContextTypes,
+    );
+    const ContextWrapper = createContextWrapperForNode(node, options.context, childContextTypes);
+    const html = renderToStaticMarkup(<ContextWrapper />);
+    return cheerio.load(html).root();
+  }
   const html = renderToStaticMarkup(node);
   return cheerio.load(html).root();
 }

test/staticRender-spec.jsx

@@ -0,0 +1,57 @@
+import React from 'react';
+import { expect } from 'chai';
+import { describeWithDOM, describeIf } from './_helpers';
+import { render } from '../src/';
+import { REACT013 } from '../src/version';
+
+describeWithDOM('render', () => {
+  describeIf(!REACT013, 'context', () => {
+    it('can pass in context', () => {
+      const SimpleComponent = React.createClass({
+        contextTypes: {
+          name: React.PropTypes.string,
+        },
+        render() {
+          return <div>{this.context.name}</div>;
+        },
+      });
+
+      const context = { name: 'foo' };
+      const wrapper = render(<SimpleComponent />, { context });
+      expect(wrapper.text()).to.equal('foo');
+    });
+    it('can pass context to the child of mounted component', () => {
+      const SimpleComponent = React.createClass({
+        contextTypes: {
+          name: React.PropTypes.string,
+        },
+        render() {
+          return <div>{this.context.name}</div>;
+        },
+      });
+      const ComplexComponent = React.createClass({
+        render() {
+          return <div><SimpleComponent /></div>;
+        },
+      });
+
+      const childContextTypes = {
+        name: React.PropTypes.string.isRequired,
+      };
+      const context = { name: 'foo' };
+      const wrapper = render(<ComplexComponent />, { context, childContextTypes });
+      expect(wrapper.children()).to.have.length(1);
+      expect(wrapper.children().first().text()).to.equal('foo');
+    });
+    it('should not throw if context is passed in but contextTypes is missing', () => {
+      const SimpleComponent = React.createClass({
+        render() {
+          return <div>{this.context.name}</div>;
+        },
+      });
+
+      const context = { name: 'foo' };
+      expect(() => render(<SimpleComponent />, { context })).to.not.throw(Error);
+    });
+  });
+});