PLT-7206: Remove the "Delete Channel" option for private channels if you're the last channel member and policy setting restricts channel deletion (#7050)

* PLT-7206: UI changes. Removed last user in channel loophole, refactored code to clean it up, added differentiated support for public and private channels, added unit tests. Still need to implement server-side checks

* PLT-7206: All helper methods in channel_utils.jsx now accept the same three boolean variables in the same order and use the same boolean logic to check their values.

* PLT-7206: Added unit tests for showManagementOptions(...)

* PLT-7206: Fixed test case descriptions

* Added unit tests for showCreateOption(...)

* PLT-7206: Added unit tests for canManageMembers(...)

* PLT-7206: Removed last person in channel loophole from server-side code

* PLT-7206: Reverted config.json

* PLT-7206: Fixed double negatives in unit test names

* PLT-7206: PR feedback - Removed confusing comment and unused variable

8 files changed, 35 insertions, 41 deletions

diff --git a/webapp/components/channel_header.jsx b/webapp/components/channel_header.jsx
index 42e66fd3a..f89c18745 100644
--- a/webapp/components/channel_header.jsx
+++ b/webapp/components/channel_header.jsx
@@ -286,10 +286,9 @@ export default class ChannelHeader extends React.Component {
             </Popover>
         );
         let channelTitle = channel.display_name;
-        const isAdmin = TeamStore.isTeamAdminForCurrentTeam() || UserStore.isSystemAdminForCurrentUser();
+        const isChannelAdmin = ChannelStore.isChannelAdminForCurrentChannel();
         const isTeamAdmin = TeamStore.isTeamAdminForCurrentTeam();
         const isSystemAdmin = UserStore.isSystemAdminForCurrentUser();
-        const isChannelAdmin = ChannelStore.isChannelAdminForCurrentChannel();
         const isDirect = (this.state.channel.type === Constants.DM_CHANNEL);
         const isGroup = (this.state.channel.type === Constants.GM_CHANNEL);
         let webrtc;
@@ -533,7 +532,7 @@ export default class ChannelHeader extends React.Component {
                     />
                 );
 
-                if (ChannelUtils.canManageMembers(channel, isSystemAdmin, isTeamAdmin, isChannelAdmin)) {
+                if (ChannelUtils.canManageMembers(channel, isChannelAdmin, isTeamAdmin, isSystemAdmin)) {
                     dropdownContents.push(
                         <li
                             key='add_members'
@@ -594,26 +593,7 @@ export default class ChannelHeader extends React.Component {
                 }
             }
 
-            const deleteOption = (
-                <li
-                    key='delete_channel'
-                    role='presentation'
-                >
-                    <ToggleModalButton
-                        id='channelDelete'
-                        role='menuitem'
-                        dialogType={DeleteChannelModal}
-                        dialogProps={{channel}}
-                    >
-                        <FormattedMessage
-                            id='channel_header.delete'
-                            defaultMessage='Delete Channel'
-                        />
-                    </ToggleModalButton>
-                </li>
-            );
-
-            if (ChannelUtils.showManagementOptions(channel, isAdmin, isSystemAdmin, isChannelAdmin)) {
+            if (ChannelUtils.showManagementOptions(channel, isChannelAdmin, isTeamAdmin, isSystemAdmin)) {
                 dropdownContents.push(
                     <li
                         key='divider-2'
@@ -679,8 +659,25 @@ export default class ChannelHeader extends React.Component {
                 );
             }
 
-            if (ChannelUtils.showDeleteOption(channel, isAdmin, isSystemAdmin, isChannelAdmin, this.state.userCount)) {
-                dropdownContents.push(deleteOption);
+            if (ChannelUtils.showDeleteOptionForCurrentUser(channel, isChannelAdmin, isTeamAdmin, isSystemAdmin)) {
+                dropdownContents.push(
+                    <li
+                        key='delete_channel'
+                        role='presentation'
+                    >
+                        <ToggleModalButton
+                            id='channelDelete'
+                            role='menuitem'
+                            dialogType={DeleteChannelModal}
+                            dialogProps={{channel}}
+                        >
+                            <FormattedMessage
+                                id='channel_header.delete'
+                                defaultMessage='Delete Channel'
+                            />
+                        </ToggleModalButton>
+                    </li>
+                );
             }
 
             const canLeave = channel.type === Constants.PRIVATE_CHANNEL ? this.state.userCount > 1 : true;
diff --git a/webapp/components/channel_members_dropdown/channel_members_dropdown.jsx b/webapp/components/channel_members_dropdown/channel_members_dropdown.jsx
index f8ff3a4f6..fbad6cde1 100644
--- a/webapp/components/channel_members_dropdown/channel_members_dropdown.jsx
+++ b/webapp/components/channel_members_dropdown/channel_members_dropdown.jsx
@@ -95,7 +95,7 @@ export default class ChannelMembersDropdown extends React.Component {
 
     // Checks if the current user has the power to remove this member from the channel.
     canRemoveMember() {
-        return canManageMembers(this.props.channel, UserStore.isSystemAdminForCurrentUser(), TeamStore.isTeamAdminForCurrentTeam(), ChannelStore.isChannelAdminForCurrentChannel());
+        return canManageMembers(this.props.channel, ChannelStore.isChannelAdminForCurrentChannel(), TeamStore.isTeamAdminForCurrentTeam(), UserStore.isSystemAdminForCurrentUser());
     }
 
     render() {
diff --git a/webapp/components/channel_members_modal.jsx b/webapp/components/channel_members_modal.jsx
index d361f6b7c..f991b7599 100644
--- a/webapp/components/channel_members_modal.jsx
+++ b/webapp/components/channel_members_modal.jsx
@@ -38,7 +38,7 @@ export default class ChannelMembersModal extends React.Component {
         const isChannelAdmin = ChannelStore.isChannelAdminForCurrentChannel();
 
         let addMembersButton = null;
-        if (canManageMembers(this.state.channel, isSystemAdmin, isTeamAdmin, isChannelAdmin) && this.state.channel.name !== Constants.DEFAULT_CHANNEL) {
+        if (canManageMembers(this.state.channel, isChannelAdmin, isTeamAdmin, isSystemAdmin) && this.state.channel.name !== Constants.DEFAULT_CHANNEL) {
             addMembersButton = (
                 <a
                     id='showInviteModal'
diff --git a/webapp/components/more_channels/more_channels.jsx b/webapp/components/more_channels/more_channels.jsx
index 45833ead2..ecc7aecf8 100644
--- a/webapp/components/more_channels/more_channels.jsx
+++ b/webapp/components/more_channels/more_channels.jsx
@@ -165,10 +165,10 @@ export default class MoreChannels extends React.Component {
             </p>
         );
 
-        const isAdmin = TeamStore.isTeamAdminForCurrentTeam() || UserStore.isSystemAdminForCurrentUser();
+        const isTeamAdmin = TeamStore.isTeamAdminForCurrentTeam();
         const isSystemAdmin = UserStore.isSystemAdminForCurrentUser();
 
-        if (!showCreateOption(Constants.OPEN_CHANNEL, isAdmin, isSystemAdmin)) {
+        if (!showCreateOption(Constants.OPEN_CHANNEL, isTeamAdmin, isSystemAdmin)) {
             createNewChannelButton = null;
             createChannelHelpText = null;
         }
diff --git a/webapp/components/navbar.jsx b/webapp/components/navbar.jsx
index 0217dc15c..25c458523 100644
--- a/webapp/components/navbar.jsx
+++ b/webapp/components/navbar.jsx
@@ -287,7 +287,6 @@ export default class Navbar extends React.Component {
     };
 
     createDropdown(channel, channelTitle, isSystemAdmin, isTeamAdmin, isChannelAdmin, isDirect, isGroup, popoverContent) {
-        const isAdmin = isSystemAdmin || isTeamAdmin;
         const infoIcon = Constants.INFO_ICON_SVG;
 
         if (channel) {
@@ -434,7 +433,7 @@ export default class Navbar extends React.Component {
                         </li>
                     );
 
-                    if (ChannelUtils.canManageMembers(channel, isSystemAdmin, isTeamAdmin, isChannelAdmin)) {
+                    if (ChannelUtils.canManageMembers(channel, isChannelAdmin, isTeamAdmin, isSystemAdmin)) {
                         manageMembersOption = (
                             <li
                                 key='manage_members'
@@ -492,7 +491,7 @@ export default class Navbar extends React.Component {
                     </li>
                 );
 
-                if (ChannelUtils.showManagementOptions(channel, isAdmin, isSystemAdmin, isChannelAdmin)) {
+                if (ChannelUtils.showManagementOptions(channel, isChannelAdmin, isTeamAdmin, isSystemAdmin)) {
                     setChannelHeaderOption = (
                         <li role='presentation'>
                             <a
@@ -539,7 +538,7 @@ export default class Navbar extends React.Component {
                     );
                 }
 
-                if (ChannelUtils.showDeleteOption(channel, isAdmin, isSystemAdmin, isChannelAdmin, this.state.userCount)) {
+                if (ChannelUtils.showDeleteOptionForCurrentUser(channel, isChannelAdmin, isTeamAdmin, isSystemAdmin)) {
                     deleteChannelOption = (
                         <li role='presentation'>
                             <ToggleModalButton
diff --git a/webapp/components/new_channel_modal/new_channel_modal.jsx b/webapp/components/new_channel_modal/new_channel_modal.jsx
index 60c0271a7..721defe08 100644
--- a/webapp/components/new_channel_modal/new_channel_modal.jsx
+++ b/webapp/components/new_channel_modal/new_channel_modal.jsx
@@ -192,13 +192,11 @@ export default class NewChannelModal extends React.PureComponent {
             </a>
         );
 
-        const isAdmin = this.props.isTeamAdmin || this.props.isSystemAdmin;
-
-        if (!ChannelUtils.showCreateOption(Constants.OPEN_CHANNEL, isAdmin, this.props.isSystemAdmin)) {
+        if (!ChannelUtils.showCreateOption(Constants.OPEN_CHANNEL, this.props.isTeamAdmin, this.props.isSystemAdmin)) {
             createPublicChannelLink = null;
         }
 
-        if (!ChannelUtils.showCreateOption(Constants.PRIVATE_CHANNEL, isAdmin, this.props.isSystemAdmin)) {
+        if (!ChannelUtils.showCreateOption(Constants.PRIVATE_CHANNEL, this.props.isTeamAdmin, this.props.isSystemAdmin)) {
             createPrivateChannelLink = null;
         }
 
diff --git a/webapp/components/popover_list_members/popover_list_members.jsx b/webapp/components/popover_list_members/popover_list_members.jsx
index e706a1cec..35d0eab6b 100644
--- a/webapp/components/popover_list_members/popover_list_members.jsx
+++ b/webapp/components/popover_list_members/popover_list_members.jsx
@@ -156,7 +156,7 @@ export default class PopoverListMembers extends React.Component {
                     />
                 );
 
-                const manageMembers = canManageMembers(this.props.channel, isSystemAdmin, isTeamAdmin, isChannelAdmin);
+                const manageMembers = canManageMembers(this.props.channel, isChannelAdmin, isTeamAdmin, isSystemAdmin);
                 const isDefaultChannel = ChannelStore.isDefault(this.props.channel);
 
                 if ((manageMembers === false && isDefaultChannel === false) || isDefaultChannel) {
diff --git a/webapp/components/sidebar.jsx b/webapp/components/sidebar.jsx
index 9b4625ea5..31d6825c8 100644
--- a/webapp/components/sidebar.jsx
+++ b/webapp/components/sidebar.jsx
@@ -714,7 +714,7 @@ export default class Sidebar extends React.Component {
             />
         );
 
-        const isAdmin = TeamStore.isTeamAdminForCurrentTeam() || UserStore.isSystemAdminForCurrentUser();
+        const isTeamAdmin = TeamStore.isTeamAdminForCurrentTeam();
         const isSystemAdmin = UserStore.isSystemAdminForCurrentUser();
 
         let createPublicChannelIcon = (
@@ -753,11 +753,11 @@ export default class Sidebar extends React.Component {
             </OverlayTrigger>
         );
 
-        if (!ChannelUtils.showCreateOption(Constants.OPEN_CHANNEL, isAdmin, isSystemAdmin)) {
+        if (!ChannelUtils.showCreateOption(Constants.OPEN_CHANNEL, isTeamAdmin, isSystemAdmin)) {
             createPublicChannelIcon = null;
         }
 
-        if (!ChannelUtils.showCreateOption(Constants.PRIVATE_CHANNEL, isAdmin, isSystemAdmin)) {
+        if (!ChannelUtils.showCreateOption(Constants.PRIVATE_CHANNEL, isTeamAdmin, isSystemAdmin)) {
             createPrivateChannelIcon = null;
         }