[MM-24061] Bring back channel sidebar hamburger icon for tablets (#4244)

* MM-24061 Bring back channel sidebar hamburger icon for tablets

* Remove channel sidebar icon for iPads

iPads run with a "persistent" sidebar already.

* Better conditional logic from PR review + tests

* Test tidying from PR review

app/screens/channel/channel_nav_bar/channel_nav_bar.js

@@ -70,6 +70,14 @@ export default class ChannelNavBar extends PureComponent {
         }
     };
 
+    drawerButtonVisible = () => {
+        if (Platform.OS === 'android') {
+            return true;
+        }
+
+        return (!DeviceTypes.IS_TABLET || this.state.isSplitView || !this.state.permanentSidebar);
+    };
+
     render() {
         const {isLandscape, onPress, theme} = this.props;
         const {openMainSidebar, openSettingsSidebar} = this.props;
@@ -99,16 +107,11 @@ export default class ChannelNavBar extends PureComponent {
             break;
         }
 
-        let drawerButtonVisible = false;
-        if (!DeviceTypes.IS_TABLET || this.state.isSplitView || !this.state.permanentSidebar) {
-            drawerButtonVisible = true;
-        }
-
         return (
             <View style={[style.header, padding(isLandscape), {height}]}>
                 <ChannelDrawerButton
                     openSidebar={openMainSidebar}
-                    visible={drawerButtonVisible}
+                    visible={this.drawerButtonVisible()}
                 />
                 <ChannelTitle
                     onPress={onPress}

app/screens/channel/channel_nav_bar/channel_nav_bar.test.js

@@ -2,15 +2,19 @@
 // See LICENSE.txt for license information.
 
 import React from 'react';
+import {Platform} from 'react-native';
 import {shallow} from 'enzyme';
 
 import Preferences from '@mm-redux/constants/preferences';
 
-import {DeviceTypes} from 'app/constants';
+import {DeviceTypes} from '@constants';
 
 import ChannelNavBar from './channel_nav_bar';
 
 jest.mock('react-intl');
+jest.mock('app/mattermost_managed', () => ({
+    isRunningInSplitView: jest.fn().mockResolvedValue(false),
+}));
 
 describe('ChannelNavBar', () => {
     const baseProps = {
@@ -49,4 +53,76 @@ describe('ChannelNavBar', () => {
 
         expect(wrapper.state('permanentSidebar')).toBeDefined();
     });
+
+    test('drawerButtonVisible appears for android tablets', () => {
+        const wrapper = shallow(
+            <ChannelNavBar {...baseProps}/>,
+        );
+
+        DeviceTypes.IS_TABLET = true;
+        Platform.OS = 'android';
+
+        expect(wrapper.instance().drawerButtonVisible()).toBe(true);
+    });
+
+    test('drawerButtonVisible appears for android phones', () => {
+        const wrapper = shallow(
+            <ChannelNavBar {...baseProps}/>,
+        );
+
+        DeviceTypes.IS_TABLET = false;
+        Platform.OS = 'android';
+
+        expect(wrapper.instance().drawerButtonVisible()).toBe(true);
+    });
+
+    test('drawerButtonVisible appears for iOS phones', () => {
+        const wrapper = shallow(
+            <ChannelNavBar {...baseProps}/>,
+        );
+
+        DeviceTypes.IS_TABLET = false;
+        Platform.OS = 'ios';
+
+        expect(wrapper.instance().drawerButtonVisible()).toBe(true);
+    });
+
+    test('drawerButtonVisible appears for iOS tablets with PermanentSidebar at default false, and not in splitview', () => {
+        const wrapper = shallow(
+            <ChannelNavBar {...baseProps}/>,
+        );
+
+        wrapper.setState({permanentSidebar: false, isSplitView: false});
+
+        DeviceTypes.IS_TABLET = true;
+        Platform.OS = 'ios';
+
+        expect(wrapper.instance().drawerButtonVisible()).toBe(true);
+    });
+
+    test('drawerButtonVisible does not appear for iOS tablets with permanentSidebar enabled', () => {
+        const wrapper = shallow(
+            <ChannelNavBar {...baseProps}/>,
+        );
+
+        wrapper.setState({permanentSidebar: true});
+
+        DeviceTypes.IS_TABLET = true;
+        Platform.OS = 'ios';
+
+        expect(wrapper.instance().drawerButtonVisible()).toBe(false);
+    });
+
+    test('drawerButtonVisible appears for iOS tablets with splitview enabled', () => {
+        const wrapper = shallow(
+            <ChannelNavBar {...baseProps}/>,
+        );
+
+        wrapper.setState({isSplitView: true});
+
+        DeviceTypes.IS_TABLET = true;
+        Platform.OS = 'ios';
+
+        expect(wrapper.instance().drawerButtonVisible()).toBe(true);
+    });
 });