Encoding::CompatibilityError - incompatible character encodings: UTF-8 and ASCII-8BIT

[harmoniqpunk]

I get this error:

Error

Encoding::CompatibilityError - incompatible character encodings: UTF-8 and ASCII-8BIT
/Library/Ruby/Gems/2.0.0/gems/cocoapods-keys-1.6.0/lib/pod/command/keys/list.rb:34:in `block in display_current_keyring'
/Library/Ruby/Gems/2.0.0/gems/cocoapods-keys-1.6.0/lib/pod/command/keys/list.rb:32:in `each'
/Library/Ruby/Gems/2.0.0/gems/cocoapods-keys-1.6.0/lib/pod/command/keys/list.rb:32:in `each_with_index'
/Library/Ruby/Gems/2.0.0/gems/cocoapods-keys-1.6.0/lib/pod/command/keys/list.rb:32:in `display_current_keyring'
/Library/Ruby/Gems/2.0.0/gems/cocoapods-keys-1.6.0/lib/pod/command/keys/list.rb:19:in `run'
/Library/Ruby/Gems/2.0.0/gems/claide-0.9.1/lib/claide/command.rb:312:in `run'
/Library/Ruby/Gems/2.0.0/gems/cocoapods-0.39.0/lib/cocoapods/command.rb:47:in `run'
/Library/Ruby/Gems/2.0.0/gems/cocoapods-0.39.0/bin/pod:44:in `<top (required)>'
/usr/local/bin/pod:23:in `load'
/usr/local/bin/pod:23:in `<main>'

this is my cocoapods-keys block in Podfile:

# How to use: https://github.com/orta/cocoapods-keys 
plugin 'cocoapods-keys', {
:project => 'mdk-example-swift',
    :target => 'mdk-example-swift',
    :keys => [
        'SandboxAppID',
        'StagingAppID',
        'ProductionAppID',
        'SandboxEndpoint',
        'StagingEndpoint',
        'ProductionEndpoint',
        'accessTokenStaging1',
        'userIdStaging1',
        'accessTokenStaging2',
        'userIdStaging2'

    ]
}

Stack:

Stack

   CocoaPods : 0.39.0
        Ruby : ruby 2.0.0p645 (2015-04-13 revision 50299) [universal.x86_64-darwin15]
    RubyGems : 2.6.1
        Host : Mac OS X 10.11.3 (15D21)
       Xcode : 7.3 (7D175)
         Git : git version 2.6.4 (Apple Git-63)
Ruby lib dir : /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib
Repositories : artsy - https://github.com/artsy/Specs.git @ 74555e9d6a1aeceddf675c2cc1fa8f9e0b740d34
               master - https://github.com/CocoaPods/Specs.git @ e4442007d7ddc4ed848f310760bb99d9e2174073
               mdklabs - https://github.com/mdklabs/ios-private-repo.git @ 5ebed0e60c2dd8ae90a27f4e772e91cb5f8e8bb8

Plugins

cocoapods-keys    : 1.6.0
cocoapods-plugins : 0.4.2
cocoapods-search  : 0.1.0
cocoapods-stats   : 0.6.2
cocoapods-trunk   : 0.6.4
cocoapods-try     : 0.5.1