Failed to install 'phonegap-plugin-push': undefined iOS @ionic 2

$pod --version

$ionic info

cli packages: (/usr/local/lib/node_modules)

@ionic/cli-utils  : 1.19.1
ionic (Ionic CLI) : 3.19.1

global packages:

cordova (Cordova CLI) : 8.0.0 

local packages:

@ionic/app-scripts : 3.1.8
Cordova Platforms  : browser 5.0.3 ios 4.5.4
Ionic Framework    : ionic-angular 3.9.2


Node  : v8.9.3
npm   : 5.5.1 
OS    : macOS High Sierra
Xcode : Xcode 9.1 Build version 9B55 

Environment Variables:

ANDROID_HOME : not set


backend : pro

ERROR while $ sudo ionic cordova platform add ios

Installing “phonegap-plugin-push” for ios
Failed to install ‘phonegap-plugin-push’: undefined
(node:1840) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): /Library/Ruby/Gems/2.3.0/gems/claide-1.0.2/lib/claide/command.rb:439:in `help!’: [!] You cannot run CocoaPods as root. (CLAide::Help)



  CocoaPods, the Cocoa library package manager.


+ cache      Manipulate the CocoaPods cache
+ env        Display pod environment
+ init       Generate a Podfile for the current directory
+ install    Install project dependencies according to versions from a
+ ipc        Inter-process communication
+ lib        Develop pods
+ list       List pods
+ outdated   Show outdated project dependencies
+ repo       Manage spec-repositories
+ setup      Setup the CocoaPods environment
+ spec       Manage pod specs
+ update     Update outdated project dependencies and create new Podfile.lock


--silent     Show nothing
--version    Show the version of the tool
--verbose    Show more debugging information
--no-ansi    Show output without ANSI codes
--help       Show help banner of specified command
from /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.1.1/lib/cocoapods/command.rb:47:in `run'
from /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.1.1/bin/pod:55:in `<top (required)>'
from /usr/local/bin/pod:22:in `load'
from /usr/local/bin/pod:22:in `<main>'

(node:1840) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

======= NOTE =====

without sudo Error: EACCES: permission denied,

Please help me on this