Support rendering React.Children.only calls. (#169)

Author: damian

src/utils/__tests__/isStatelessComponent-test.js

@@ -99,6 +99,34 @@ describe('isStatelessComponent', () => {
     });
   });
 
+  describe('Stateless Function Components with React.Children.only', () => {
+    it('accepts simple arrow function components', () => {
+      var def = parse(`
+        var React = require('react');
+        var Foo = ({ children }) => React.Children.only(children, null);
+      `).get('body', 1).get('declarations', [0]).get('init');
+
+      expect(isStatelessComponent(def)).toBe(true);
+    });
+
+    it('accepts simple function expressions components', () => {
+      var def = parse(`
+        var React = require('react');
+        let Foo = function({ children }) { return React.Children.only(children, null); };
+      `).get('body', 1).get('declarations', [0]).get('init');
+
+      expect(isStatelessComponent(def)).toBe(true);
+    });
+
+    it('accepts simple function declaration components', () => {
+      var def = parse(`
+        var React = require('react');
+        function Foo ({ children }) { return React.Children.only(children, null); }
+      `).get('body', 1);
+      expect(isStatelessComponent(def)).toBe(true);
+    });
+  });
+
   describe('Stateless Function Components inside module pattern', () => {
     it('', () => {
       var def = parse(`

src/utils/isReactChildrenElementCall.js

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2015, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @flow
+ *
+ */
+
+import isReactModuleName from './isReactModuleName';
+import match from './match';
+import recast from 'recast';
+import resolveToModule from './resolveToModule';
+
+var {types: {namedTypes: types}} = recast;
+
+/**
+ * Returns true if the expression is a function call of the form
+ * `React.Children.only(...)`.
+ */
+export default function isReactChildrenElementCall(path: NodePath): boolean {
+  if (types.ExpressionStatement.check(path.node)) {
+    path = path.get('expression');
+  }
+
+  if (!match(path.node, {callee: {property: {name: 'only'}}})) {
+    return false;
+  }
+
+  var calleeObj = path.get('callee', 'object');
+  var module = resolveToModule(calleeObj);
+
+  if (!match(calleeObj, { value: { property: { name: 'Children' }}})) {
+    return false;
+  }
+
+  return Boolean(module && isReactModuleName(module));
+}

src/utils/isStatelessComponent.js

@@ -14,6 +14,7 @@ import isReactComponentClass from './isReactComponentClass';
 import isReactCreateClassCall from './isReactCreateClassCall';
 import isReactCreateElementCall from './isReactCreateElementCall';
 import isReactCloneElementCall from './isReactCloneElementCall';
+import isReactChildrenElementCall from './isReactChildrenElementCall';
 import recast from 'recast';
 import resolveToValue from './resolveToValue';
 
@@ -32,7 +33,8 @@ function isJSXElementOrReactCreateElement(path) {
   return (
     path.node.type === 'JSXElement' ||
     (path.node.type === 'CallExpression' && isReactCreateElementCall(path)) ||
-    (path.node.type === 'CallExpression' && isReactCloneElementCall(path))
+    (path.node.type === 'CallExpression' && isReactCloneElementCall(path)) ||
+    (path.node.type === 'CallExpression' && isReactChildrenElementCall(path))
   );
 }