Add mount() API for wrapping the root in a component

SUMMARY.md

@@ -42,6 +42,7 @@
     * [first()](/docs/api/ShallowWrapper/first.md)
     * [forEach(fn)](/docs/api/ShallowWrapper/forEach.md)
     * [get(index)](/docs/api/ShallowWrapper/get.md)
+    * [getWrappingComponent()](/docs/api/ShallowWrapper/getWrappingComponent.md)
     * [getElement(index)](/docs/api/ShallowWrapper/getElement.md)
     * [getElements(index)](/docs/api/ShallowWrapper/getElements.md)
     * [hasClass(className)](/docs/api/ShallowWrapper/hasClass.md)
@@ -104,6 +105,7 @@
     * [forEach(fn)](/docs/api/ReactWrapper/forEach.md)
     * [get(index)](/docs/api/ReactWrapper/get.md)
     * [getDOMNode()](/docs/api/ReactWrapper/getDOMNode.md)
+    * [getWrappingComponent()](/docs/api/ReactWrapper/getWrappingComponent.md)
     * [hasClass(className)](/docs/api/ReactWrapper/hasClass.md)
     * [hostNodes()](/docs/api/ReactWrapper/hostNodes.md)
     * [html()](/docs/api/ReactWrapper/html.md)

docs/api/ReactWrapper/getWrappingComponent.md

@@ -0,0 +1,45 @@
+# `.getWrappingComponent() => ReactWrapper`
+
+If a `wrappingComponent` was passed in `options`, this methods returns a `ReactWrapper` around the rendered `wrappingComponent`. This `ReactWrapper` can be used to update the `wrappingComponent`'s props, state, etc.
+
+
+#### Returns
+
+`ReactWrapper`: A `ReactWrapper` around the rendered `wrappingComponent`
+
+
+
+#### Examples
+
+```jsx
+import { Provider } from 'react-redux';
+import { Router } from 'react-router';
+import store from './my/app/store';
+import mockStore from './my/app/mockStore';
+
+function MyProvider(props) {
+  const { children, customStore } = props;
+
+  return (
+    <Provider store={customStore || store}>
+      <Router>
+        {children}
+      </Router>
+    </Provider>
+  );
+}
+MyProvider.propTypes = {
+  children: PropTypes.node,
+  customStore: PropTypes.shape({}),
+};
+MyProvider.defaultProps = {
+  children: null,
+  customStore: null,
+};
+
+const wrapper = mount(<MyComponent />, {
+  wrappingComponent: MyProvider,
+});
+const provider = wrapper.getWrappingComponent();
+provider.setProps({ customStore: mockStore });
+```

docs/api/ShallowWrapper/getWrappingComponent.md

@@ -0,0 +1,45 @@
+# `.getWrappingComponent() => ShallowWrapper`
+
+If a `wrappingComponent` was passed in `options`, this methods returns a `ShallowWrapper` around the rendered `wrappingComponent`. This `ShallowWrapper` can be used to update the `wrappingComponent`'s props, state, etc.
+
+
+#### Returns
+
+`ShallowWrapper`: A `ShallowWrapper` around the rendered `wrappingComponent`
+
+
+
+#### Examples
+
+```jsx
+import { Provider } from 'react-redux';
+import { Router } from 'react-router';
+import store from './my/app/store';
+import mockStore from './my/app/mockStore';
+
+function MyProvider(props) {
+  const { children, customStore } = props;
+
+  return (
+    <Provider store={customStore || store}>
+      <Router>
+        {children}
+      </Router>
+    </Provider>
+  );
+}
+MyProvider.propTypes = {
+  children: PropTypes.node,
+  customStore: PropTypes.shape({}),
+};
+MyProvider.defaultProps = {
+  children: null,
+  customStore: null,
+};
+
+const wrapper = shallow(<MyComponent />, {
+  wrappingComponent: MyProvider,
+});
+const provider = wrapper.getWrappingComponent();
+provider.setProps({ customStore: mockStore });
+```

docs/api/mount.md

@@ -49,6 +49,8 @@ describe('<Foo />', () => {
 - `options.context`: (`Object` [optional]): Context to be passed into the component
 - `options.attachTo`: (`DOMElement` [optional]): DOM Element to attach the component to.
 - `options.childContextTypes`: (`Object` [optional]): Merged contextTypes for all children of the wrapper.
+- `options.wrappingComponent`: (`ComponentType` [optional]): A component that will render as a parent of the `node`. It can be used to provide context to the `node`, among other things. See the [`getWrappingComponent()` docs](ReactWrapper/getWrappingComponent.md) for an example. **Note**: `wrappingComponent` _must_ render its children.
+- `options.wrappingComponentProps`: (`Object` [optional]): Initial props to pass to the `wrappingComponent` if it is specified.
 
 #### Returns
 
@@ -177,6 +179,9 @@ Manually sets context of the root component.
 #### [`.instance() => ReactComponent|DOMComponent`](ReactWrapper/instance.md)
 Returns the wrapper's underlying instance.
 
+#### [`.getWrappingComponent() => ReactWrapper`](ReactWrapper/getWrappingComponent.md)
+Returns a wrapper representing the `wrappingComponent`, if one was passed.
+
 #### [`.unmount() => ReactWrapper`](ReactWrapper/unmount.md)
 A method that un-mounts the component.
 

docs/api/shallow.md

@@ -50,6 +50,8 @@ describe('<MyComponent />', () => {
   - `options.disableLifecycleMethods`: (`Boolean` [optional]): If set to true, `componentDidMount`
 is not called on the component, and `componentDidUpdate` is not called after
 [`setProps`](ShallowWrapper/setProps.md) and [`setContext`](ShallowWrapper/setContext.md). Default to `false`.
+- `options.wrappingComponent`: (`ComponentType` [optional]): A component that will render as a parent of the `node`. It can be used to provide context to the `node`, among other things. See the [`getWrappingComponent()` docs](ShallowWrapper/getWrappingComponent.md) for an example. **Note**: `wrappingComponent` _must_ render its children.
+- `options.wrappingComponentProps`: (`Object` [optional]): Initial props to pass to the `wrappingComponent` if it is specified.
 
 #### Returns
 
@@ -187,6 +189,9 @@ Manually sets props of the root component.
 #### [`.setContext(context) => ShallowWrapper`](ShallowWrapper/setContext.md)
 Manually sets context of the root component.
 
+#### [`.getWrappingComponent() => ShallowWrapper`](ShallowWrapper/getWrappingComponent.md)
+Returns a wrapper representing the `wrappingComponent`, if one was passed.
+
 #### [`.instance() => ReactComponent`](ShallowWrapper/instance.md)
 Returns the instance of the root component.
 

packages/enzyme-test-suite/test/ReactWrapper-spec.jsx

@@ -172,6 +172,178 @@ describeWithDOM('mount', () => {
       expect(() => wrapper.state('key')).to.throw('ReactWrapper::state("key") requires that `state` not be `null` or `undefined`');
     });
 
+    describeIf(is('>= 0.14'), 'wrappingComponent', () => {
+      const realCreateMountRenderer = getAdapter().createMountRenderer;
+      let wrapper;
+
+      class More extends React.Component {
+        render() {
+          return null;
+        }
+      }
+
+      class TestProvider extends React.Component {
+        getChildContext() {
+          const { value, renderMore } = this.props;
+
+          return {
+            testContext: value || 'Hello world!',
+            renderMore: renderMore || false,
+          };
+        }
+
+        render() {
+          const { children } = this.props;
+
+          return children;
+        }
+      }
+      TestProvider.childContextTypes = {
+        testContext: PropTypes.string,
+        renderMore: PropTypes.bool,
+      };
+
+      class MyWrappingComponent extends React.Component {
+        render() {
+          const { children, contextValue, renderMore } = this.props;
+
+          return (
+            <div>
+              <TestProvider value={contextValue} renderMore={renderMore}>{children}</TestProvider>
+            </div>
+          );
+        }
+      }
+
+      class MyComponent extends React.Component {
+        render() {
+          const { testContext, renderMore } = this.context;
+
+          return (
+            <div>
+              <div>Context says: {testContext}</div>
+              {renderMore && <More />}
+            </div>
+          );
+        }
+      }
+      MyComponent.contextTypes = TestProvider.childContextTypes;
+
+      beforeEach(() => {
+        wrapper = mount(<MyComponent />, {
+          wrappingComponent: MyWrappingComponent,
+        });
+      });
+
+      it('mounts the passed node as the root as per usual', () => {
+        expect(wrapper.type()).to.equal(MyComponent);
+        expect(wrapper.parent().exists()).to.equal(false);
+        expect(() => wrapper.setProps({ foo: 'bar' })).not.to.throw();
+      });
+
+      it('renders the root in the wrapping component', () => {
+        // Context will only be set properly if the root node is rendered as a descendent of
+        // the wrapping component.
+        expect(wrapper.text()).to.equal('Context says: Hello world!');
+      });
+
+      it('supports mounting the wrapping component with initial props', () => {
+        wrapper.unmount();
+        wrapper = mount(<MyComponent />, {
+          wrappingComponent: MyWrappingComponent,
+          wrappingComponentProps: { contextValue: 'I can be set!' },
+        });
+        expect(wrapper.text()).to.equal('Context says: I can be set!');
+      });
+
+      it('throws an error if the wrappingComponent does not render its children', () => {
+        class BadWrapper extends React.Component {
+          render() {
+            return <div />;
+          }
+        }
+        expect(() => mount(<MyComponent />, {
+          wrappingComponent: BadWrapper,
+        })).to.throw('`wrappingComponent` must render its children!');
+      });
+
+      describe('getWrappingComponent()', () => {
+        let wrappingComponent;
+
+        beforeEach(() => {
+          wrappingComponent = wrapper.getWrappingComponent();
+        });
+
+        it('gets a ReactWrapper for the wrappingComponent', () => {
+          expect(wrappingComponent.type()).to.equal(MyWrappingComponent);
+          expect(wrappingComponent.parent().exists()).to.equal(false);
+
+          wrappingComponent.setProps({ contextValue: 'this is a test.' });
+          expect(wrapper.text()).to.equal('Context says: this is a test.');
+        });
+
+        it('updates the wrapper when the wrappingComponent is updated', () => {
+          wrappingComponent.setProps({ renderMore: true });
+          expect(wrapper.find(More).exists()).to.equal(true);
+        });
+
+        it('updates the wrappingComponent when the root is updated', () => {
+          wrapper.unmount();
+          expect(wrappingComponent.exists()).to.equal(false);
+        });
+
+        it('handles the wrapper being unmounted', () => {
+          wrapper.unmount();
+          wrappingComponent.update();
+          expect(wrappingComponent.exists()).to.equal(false);
+          expect(() => wrappingComponent.setProps({})).to.throw('The wrapping component may not be updated if the root is unmounted.');
+        });
+
+        it('handles a partial prop update', () => {
+          wrappingComponent.setProps({ contextValue: 'hello' });
+          wrappingComponent.setProps({ foo: 'bar' });
+          expect(wrappingComponent.prop('foo')).to.equal('bar');
+          expect(wrappingComponent.prop('contextValue')).to.equal('hello');
+        });
+
+        it('cannot be called on the non-root', () => {
+          expect(() => wrapper.find('div').getWrappingComponent()).to.throw('ReactWrapper::getWrappingComponent() can only be called on the root');
+        });
+
+        it('cannot be called on itself', () => {
+          expect(() => wrappingComponent.getWrappingComponent()).to.throw('ReactWrapper::getWrappingComponent() can only be called on the root');
+        });
+
+        it('throws an error if `wrappingComponent` was not provided', () => {
+          wrapper.unmount();
+          wrapper = mount(<MyComponent />);
+          expect(() => wrapper.getWrappingComponent()).to.throw('ReactWrapper::getWrappingComponent() can only be called on a wrapper that was originally passed a `wrappingComponent` option');
+        });
+      });
+
+      wrap()
+        .withOverrides(() => getAdapter(), () => ({
+          RootFinder: undefined,
+          createMountRenderer: (...args) => {
+            const renderer = realCreateMountRenderer(...args);
+            delete renderer.getWrappingComponentRenderer;
+            renderer.getNode = () => null;
+            return renderer;
+          },
+        }))
+        .describe('with an old adapter', () => {
+          it('renders fine when wrappingComponent is not passed', () => {
+            wrapper = mount(<MyComponent />);
+          });
+
+          it('throws an error if wrappingComponent is passed', () => {
+            expect(() => mount(<MyComponent />, {
+              wrappingComponent: MyWrappingComponent,
+            })).to.throw('your adapter does not support `wrappingComponent`. Try upgrading it!');
+          });
+        });
+    });
+
     describeIf(is('>= 16.3'), 'uses the isValidElementType from the Adapter to validate the prop type of Component', () => {
       const Foo = () => null;
       const Bar = () => null;