add portal shallow support

Author: Jason Zukewich

packages/enzyme-adapter-utils/package.json

@@ -36,7 +36,8 @@
   "dependencies": {
     "function.prototype.name": "^1.1.0",
     "object.assign": "^4.1.0",
-    "prop-types": "^15.6.2"
+    "prop-types": "^15.6.2",
+    "react-is": "^16.4.2"
   },
   "peerDependencies": {
     "react": "0.13.x || 0.14.x || ^15.0.0-0 || ^16.0.0-0"

packages/enzyme-adapter-utils/src/Utils.js

@@ -1,6 +1,9 @@
 import functionName from 'function.prototype.name';
 import createMountWrapper from './createMountWrapper';
 import createRenderWrapper from './createRenderWrapper';
+import {
+  Portal,
+} from 'react-is';
 
 export { createMountWrapper, createRenderWrapper };
 
@@ -94,6 +97,10 @@ export function displayNameOfNode(node) {
 
   if (!type) return null;
 
+  if (type === Portal) {
+    return 'Portal';
+  }
+
   return type.displayName || (typeof type === 'function' ? functionName(type) : type.name || type);
 }
 
@@ -104,6 +111,9 @@ export function nodeTypeFromType(type) {
   if (type && type.prototype && type.prototype.isReactComponent) {
     return 'class';
   }
+  if (type && type === Portal) {
+    return 'portal';
+  }
   return 'function';
 }
 
@@ -168,9 +178,20 @@ export function ensureKeyOrUndefined(key) {
 }
 
 export function elementToTree(el) {
-  if (el === null || typeof el !== 'object' || !('type' in el)) {
+  if (el === null || typeof el !== 'object' || !('type' in el || el.$$typeof === Portal)) {
     return el;
   }
+  if (el.$$typeof === Portal) {
+    return {
+      nodeType: nodeTypeFromType(Portal),
+      type: Portal,
+      props: {},
+      key: ensureKeyOrUndefined(el.key),
+      ref: el.ref,
+      instance: null,
+      rendered: elementToTree(el.children),
+    };
+  }
   const {
     type,
     props,

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

@@ -35,6 +35,9 @@ import {
   REACT16,
   is,
 } from './_helpers/version';
+import {
+  Portal,
+} from 'react-is';
 import realArrowFunction from './_helpers/realArrowFunction';
 import sloppyReturnThis from './_helpers/untranspiledSloppyReturnThis';