feat(list): Add list divider (#420)

packages/list/ListDivider.js

@@ -0,0 +1,54 @@
+// The MIT License
+//
+// Copyright (c) 2018 Google, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+import React from 'react';
+import PropTypes from 'prop-types';
+import classnames from 'classnames';
+
+const ListDivider = (props) => {
+  const {
+    tag: Tag,
+    className,
+    ...otherProps
+  } = props;
+
+  return (
+    <Tag
+      className={classnames('mdc-list-divider', className)}
+      {...otherProps}
+    />
+  );
+};
+
+ListDivider.propTypes = {
+  className: PropTypes.string,
+  tag: PropTypes.string,
+  role: PropTypes.string,
+};
+
+ListDivider.defaultProps = {
+  className: '',
+  tag: 'li',
+  role: 'separator',
+};
+
+export default ListDivider;

packages/list/README.md

@@ -110,11 +110,9 @@ class MyApp extends Component {
 }
 ```
 
-### List groups
+### List groups and list dividers
 
-Multiple related lists can be grouped together using the `ListGroup` component. Optional subheaders can be added using `ListGroupSubheader`.
-
-> _NOTE_: You can override the element that the `ListGroup` or `ListGroupSubheader` renders by passing in a `tag` prop. By default, `ListGroup` renders a `div` and `ListGroupSubheader` renders an `h3`.
+Multiple related lists can be grouped together using the `ListGroup` component. Optional subheaders can be added using `ListGroupSubheader`. `ListDivider`s can be used to separate content either within a list or between lists.
 
 ```js
 import React, {Component} from 'react';
@@ -129,6 +127,7 @@ class MyApp extends Component {
           <ListItem><ListItemText primaryText='Photos' /></ListItem>
           ...
         </List>
+        <ListDivider />
         <ListGroupSubheader tag='h2'>Recent Files</ListGroupSubheader>
         <List>
           <ListItem><ListItemText primaryText='Vacation' /></ListItem>
@@ -237,6 +236,29 @@ tabIndex | Number | Tab index of the list item meta
 tabbableOnListItemFocus | Boolean | Whether focusing list item will toggle tab index of the list item meta. If false, the tab index will always be -1
 meta | Element or String | The meta element or string to be displayed behind list item text
 
+### ListDivider
+
+Prop Name | Type | Description
+--- | --- | ---
+className | String | Classes to be applied to the list divider
+tag | String | Element tag of the list divider, defaults to `li`
+role | String | ARIA role of the list divider, defaults to `separator`
+
+### ListGroup
+
+Prop Name | Type | Description
+--- | --- | ---
+className | String | Classes to be applied to the list group
+tag | String | Element tag of the list group, defaults to `div`
+
+
+### ListGroupSubheader
+
+Prop Name | Type | Description
+--- | --- | ---
+className | String | Classes to be applied to the list group subheader
+tag | String | Element tag of the list group subheader, defaults to `h3`
+
 ## Sass Mixins
 
 Sass mixins may be available to customize various aspects of the Components. Please refer to the MDC Web repository for more information on what mixins are available, and how to use them.

packages/list/index.js

@@ -30,6 +30,7 @@ import ListItem from './ListItem';
 import ListItemGraphic from './ListItemGraphic';
 import ListItemText from './ListItemText';
 import ListItemMeta from './ListItemMeta';
+import ListDivider from './ListDivider';
 import ListGroup from './ListGroup';
 import ListGroupSubheader from './ListGroupSubheader';
 
@@ -308,4 +309,4 @@ List.defaultProps = {
 
 /* eslint-enable quote-props */
 
-export {ListItem, ListItemGraphic, ListItemText, ListItemMeta, ListGroup, ListGroupSubheader};
+export {ListItem, ListItemGraphic, ListItemText, ListItemMeta, ListDivider, ListGroup, ListGroupSubheader};

test/screenshot/list/index.js

@@ -8,6 +8,7 @@ import List, {
   ListItemGraphic,
   ListItemText,
   ListItemMeta,
+  ListDivider,
   ListGroup,
   ListGroupSubheader,
 } from '../../../packages/list/index';
@@ -63,7 +64,7 @@ const ListScreenshotTest = () => {
         {renderListItem('List item', 'Secondary text')}
         {renderListItem('List item', 'Secondary text')}
         {renderListItem('List item', 'Secondary text')}
-        <li className='mdc-list-divider' role='separator'></li>
+        <ListDivider />
         {renderListItem('List item', 'Secondary text')}
         {renderListItem('List item', 'Secondary text')}
       </List>

test/unit/list/ListDivider.test.js

@@ -0,0 +1,26 @@
+import React from 'react';
+import {assert} from 'chai';
+import {shallow} from 'enzyme';
+import {ListDivider} from '../../../packages/list';
+
+suite('ListDivider');
+
+test('className adds classes', () => {
+  const wrapper = shallow(<ListDivider className='test-class-name' />);
+  assert.isTrue(wrapper.hasClass('test-class-name'));
+});
+
+test('has mdc-list-divider class', () => {
+  const wrapper = shallow(<ListDivider />);
+  assert.isTrue(wrapper.hasClass('mdc-list-divider'));
+});
+
+test('has separator role by default', () => {
+  const wrapper = shallow(<ListDivider />);
+  assert.equal(wrapper.props().role, 'separator');
+});
+
+test('renders with given tag', () => {
+  const wrapper = shallow(<ListDivider tag='span' />);
+  assert.exists(wrapper.find('span'));
+});