add tests

packages/enzyme-adapter-react-16/src/ReactSixteenAdapter.js

@@ -359,6 +359,7 @@ class ReactSixteenAdapter extends EnzymeAdapter {
       case Fragment: return 'Fragment';
       case StrictMode: return 'StrictMode';
       case Profiler: return 'Profiler';
+      case Portal: return 'Portal';
 
       default: {
         const $$typeofType = type && type.$$typeof;
@@ -370,7 +371,6 @@ class ReactSixteenAdapter extends EnzymeAdapter {
             const name = type.render.displayName || functionName(type.render);
             return name ? `ForwardRef(${name})` : 'ForwardRef';
           }
-          case Portal: return 'Portal';
           default: return displayNameOfNode(node);
         }
       }

packages/enzyme-test-suite/package.json

@@ -50,4 +50,4 @@
     "eslint-plugin-jsx-a11y": "^6.1.0",
     "eslint-plugin-react": "^7.10.0"
   }
-}
+}

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

@@ -6,7 +6,7 @@ import { configure, shallow } from 'enzyme';
 
 import './_helpers/setupAdapters';
 import Adapter from './_helpers/adapter';
-import { renderToString } from './_helpers/react-compat';
+import { renderToString, createContext, createPortal, forwardRef } from './_helpers/react-compat';
 import { REACT013, REACT16 } from './_helpers/version';
 import { itIf, describeWithDOM } from './_helpers';
 
@@ -801,4 +801,69 @@ describe('Adapter', () => {
       },
     }));
   });
+
+  it.only('should determine valid element types', () => {
+    const renderer = adapter.createRenderer({ mode: 'shallow' });
+
+    class Component extends React.Component {
+      render() { return null }
+    }
+    const ArrowFunction = () => null
+
+    expect(adapter.isValidElementType('div')).to.equal(true);
+    expect(adapter.isValidElementType(Component)).to.equal(true);
+    expect(adapter.isValidElementType(ArrowFunction )).to.equal(true);
+
+    if (createPortal) {
+      expect(adapter.isValidElementType(createPortal(<div />, { nodeType: 1 }))).to.equal(false);
+    }
+
+    if (createContext) {
+      const Context = createContext({ })
+      expect(adapter.isValidElementType(Context.Consumer)).to.equal(true);
+      expect(adapter.isValidElementType(Context.Provider)).to.equal(true);
+    }
+
+    if (forwardRef) {
+      expect(adapter.isValidElementType(forwardRef(() => null))).to.equal(true);
+    }
+  });
+
+  it('should provide node displayNames', () => {
+    const getDisplayName = el =>
+      adapter.displayNameOfNode(adapter.elementToNode(el))
+
+    class Component extends React.Component {
+      render() { return null }
+    }
+    class Something extends React.Component {
+      render() { return null }
+    }
+    Something.displayName = 'MyComponent'
+
+    const ArrowFunction = () => null
+
+    expect(getDisplayName(<div/>)).to.equal('div');
+    expect(getDisplayName(<Component />)).to.equal('Component');
+    expect(getDisplayName(<Something />)).to.equal('MyComponent');
+    expect(getDisplayName(<ArrowFunction />)).to.equal('ArrowFunction');
+
+    if (createPortal) {
+      expect(getDisplayName(createPortal(<div />, { nodeType: 1 }))).to.equal('Portal');
+    }
+
+    if (createContext) {
+      const Context = createContext({ })
+      expect(getDisplayName(<Context.Consumer />)).to.equal('ContextConsumer');
+      expect(getDisplayName(<Context.Provider />)).to.equal('ContextProvider');
+    }
+
+    if (forwardRef) {
+      const ForwaredRef = forwardRef(() => null);
+      const NamedForwardedRef = forwardRef(function Named() { return null });
+
+      expect(getDisplayName(<ForwaredRef />)).to.equal('forwardRef');
+      expect(getDisplayName(<NamedForwardedRef />)).to.equal('forwardRef(Named)');
+    }
+  });
 });

packages/enzyme-test-suite/test/_helpers/react-compat.js

@@ -10,6 +10,7 @@ let createClass;
 let renderToString;
 let createPortal;
 let createContext;
+let forwardRef;
 
 if (is('>=15.5 || ^16.0.0-alpha || ^16.3.0-alpha')) {
   // eslint-disable-next-line import/no-extraneous-dependencies
@@ -32,9 +33,10 @@ if (is('^16.0.0-alpha || ^16.3.0-alpha')) {
 }
 
 if (is('^16.3.0-0')) {
-  ({ createContext } = require('react'));
+  ({ createContext, forwardRef } = require('react'));
 } else {
   createContext = null;
+  forwardRef = null;
 }
 
 export {