| 1 | /** |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * |
| 4 | * This source code is licensed under the MIT license found in the |
| 5 | * LICENSE file in the root directory of this source tree. |
| 6 | * |
| 7 | * @emails react-core |
| 8 | */ |
| 9 | |
| 10 | 'use strict'; |
| 11 | |
| 12 | describe('onlyChild', () => { |
| 13 | let React; |
| 14 | let WrapComponent; |
| 15 | |
| 16 | beforeEach(() => { |
| 17 | React = require('react'); |
| 18 | WrapComponent = class extends React.Component { |
| 19 | render() { |
| 20 | return ( |
| 21 | <div> |
| 22 | {React.Children.only(this.props.children, this.props.mapFn, this)} |
| 23 | </div> |
| 24 | ); |
| 25 | } |
| 26 | }; |
| 27 | }); |
| 28 | |
| 29 | it('should fail when passed two children', () => { |
| 30 | expect(function () { |
| 31 | const instance = ( |
| 32 | <WrapComponent> |
| 33 | <div /> |
| 34 | <span /> |
| 35 | </WrapComponent> |
| 36 | ); |
| 37 | React.Children.only(instance.props.children); |
| 38 | }).toThrow(); |
| 39 | }); |
| 40 | |
| 41 | it('should fail when passed nully values', () => { |
| 42 | expect(function () { |
| 43 | const instance = <WrapComponent>{null}</WrapComponent>; |
| 44 | React.Children.only(instance.props.children); |
| 45 | }).toThrow(); |
| 46 | |
| 47 | expect(function () { |
| 48 | const instance = <WrapComponent>{undefined}</WrapComponent>; |
| 49 | React.Children.only(instance.props.children); |
| 50 | }).toThrow(); |
| 51 | }); |
| 52 | |
| 53 | it('should fail when key/value objects', () => { |
| 54 | expect(function () { |
| 55 | const instance = <WrapComponent>{[<span key="abc" />]}</WrapComponent>; |
| 56 | React.Children.only(instance.props.children); |
| 57 | }).toThrow(); |
| 58 | }); |
| 59 | |
| 60 | it('should not fail when passed interpolated single child', () => { |
| 61 | expect(function () { |
| 62 | const instance = <WrapComponent>{<span />}</WrapComponent>; |
| 63 | React.Children.only(instance.props.children); |
| 64 | }).not.toThrow(); |
| 65 | }); |
| 66 | |
| 67 | it('should return the only child', () => { |
| 68 | const instance = ( |
| 69 | <WrapComponent> |
| 70 | <span /> |
| 71 | </WrapComponent> |
| 72 | ); |
| 73 | expect(React.Children.only(instance.props.children)).toEqual(<span />); |
| 74 | }); |
| 75 | }); |