Ionic 3 project cannot build for ios after installing OneSignal plugin

I created a new project and installed the OneSignal plugin.

sudo ionic cordova plugin add theignal-cordova plugin

sudo npm install --save @ ionic-native / onesignal

After that I built for Android everything is fine, but I built for iOS.

sudo ionic cordova build ios

He gave me a message like this →

    Lolzzs-MacBook-Pro:myOnesignal lolzzlolzz$ sudo ionic cordova build ios
> cordova platform add --save ios
✖ Running command - failed!
[ERROR] An error occurred while running cordova platform add --save ios (exit code 1):

        Using cordova-fetch for cordova-ios@~4.4.0
        Adding ios project...
        Creating Cordova project for the iOS platform:
                Path: platforms/ios
                Package: io.ionic.starter
                Name: MyApp
        iOS project created with cordova-ios@4.4.0
        Installing "cordova-plugin-console" for ios
        Installing "cordova-plugin-device" for ios
        Installing "cordova-plugin-splashscreen" for ios
        Installing "cordova-plugin-statusbar" for ios
        Installing "cordova-plugin-whitelist" for ios
        Installing "ionic-plugin-keyboard" for ios
        Installing "onesignal-cordova-plugin" for ios
        Failed to install 'onesignal-cordova-plugin': undefined
        Error: /usr/local/lib/ruby/gems/2.4.0/gems/claide-1.0.1/lib/claide/command.rb:439:in
 `help!': [!] You cannot run CocoaPods as root. (CLAide::Help)

        Usage:

            $ pod COMMAND

              CocoaPods, the Cocoa library package manager.

        Commands:
+ 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
                         Podfile.lock
            + 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            + outdated   Show outdated project dependencies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            + update     Update outdated project dependencies and create new Podfile.lock

        Options:

            --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 /usr/local/lib/ruby/gems/2.4.0/gems/cocoapods-1.2.1/lib/cocoapods/comma
nd.rb:47:in `run'
                from /usr/local/lib/ruby/gems/2.4.0/gems/cocoapods-1.2.1/bin/pod:55:in `<top
 (required)>'
                from /usr/local/bin/pod:22:in `load'
                from /usr/local/bin/pod:22:in `<main>'