### Error

ArgumentError - Malformed version number string
/Library/Ruby/Site/2.3.0/rubygems/version.rb:209:in initialize' /Library/Ruby/Site/2.3.0/rubygems/version.rb:200:innew'
/Library/Ruby/Site/2.3.0/rubygems/version.rb:200:in new' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/generator/xcconfig/aggregate_xcconfig.rb:119:inembedded_content_settings'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/generator/xcconfig/aggregate_xcconfig.rb:64:in generate' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/generator/xcconfig/aggregate_xcconfig.rb:39:insave_as'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator/target_installer.rb:114:in update_changed_file' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator/aggregate_target_installer.rb:87:inblock in create_xcconfig_file'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator/aggregate_target_installer.rb:84:in each' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator/aggregate_target_installer.rb:84:increate_xcconfig_file'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator/aggregate_target_installer.rb:18:in block in install!' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/user_interface.rb:142:inmessage'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator/aggregate_target_installer.rb:14:in install!' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator.rb:175:inblock (2 levels) in install_libraries'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator.rb:173:in each' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator.rb:173:inblock in install_libraries'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/user_interface.rb:142:in message' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator.rb:167:ininstall_libraries'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer/xcode/pods_project_generator.rb:65:in generate!' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer.rb:184:inblock in generate_pods_project'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/user_interface.rb:64:in section' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer.rb:183:ingenerate_pods_project'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/installer.rb:119:in install!' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/command/install.rb:41:inrun'
/Library/Ruby/Gems/2.3.0/gems/claide-1.0.2/lib/claide/command.rb:334:in run' /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/command.rb:52:inrun'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/bin/pod:55:in <top (required)>' /usr/local/bin/pod:23:inload'
/usr/local/bin/pod:23:in `<main>'

――― TEMPLATE END ――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――

[!] Oh no, an error occurred.

Search for existing GitHub issues similar to yours:
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Looking for related issues on cocoapods/cocoapods...
Could not access the GitHub API, you may have better luck via the website.
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/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/user_interface/inspector_reporter.rb:74:in `inspector_could_not_create_report': undefined method `name' for #<Net::OpenTimeout: Net::OpenTimeout> (NoMethodError)
    from /Library/Ruby/Gems/2.3.0/gems/gh_inspector-1.1.3/lib/gh_inspector/sidekick.rb:30:in `rescue in search'
    from /Library/Ruby/Gems/2.3.0/gems/gh_inspector-1.1.3/lib/gh_inspector/sidekick.rb:27:in `search'
    from /Library/Ruby/Gems/2.3.0/gems/gh_inspector-1.1.3/lib/gh_inspector/inspector.rb:68:in `search_query'
    from /Library/Ruby/Gems/2.3.0/gems/gh_inspector-1.1.3/lib/gh_inspector/inspector.rb:62:in `search_exception'
    from /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/user_interface/error_report.rb:119:in `search_for_exceptions'
    from /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/command.rb:67:in `report_error'
    from /Library/Ruby/Gems/2.3.0/gems/claide-1.0.2/lib/claide/command.rb:396:in `handle_exception'
    from /Library/Ruby/Gems/2.3.0/gems/claide-1.0.2/lib/claide/command.rb:337:in `rescue in run'
    from /Library/Ruby/Gems/2.3.0/gems/claide-1.0.2/lib/claide/command.rb:324:in `run'
    from /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/lib/cocoapods/command.rb:52:in `run'
    from /Library/Ruby/Gems/2.3.0/gems/cocoapods-1.4.0/bin/pod:55:in `<top (required)>'
    from /usr/local/bin/pod:23:in `load'
    from /usr/local/bin/pod:23:in `<main>'

解决办法：
gem 2.7.7 can not run cocoapods 1.3.x . 1.4.x
you should install rubygem in 2.7.6
please:
gem install rubygems-update -v 2.7.6
and
update_rubygems

then
pod install or pod update

如果你的电脑收到管制，没有写入 /usr/bin 路径的权限
执行sudo gem update --system 2.3.0 -n /usr/local/bin

2.7.6版本的安装可能会报：
ERROR: While executing gem ... (Errno::EPERM)
Operation not permitted @ rb_sysopen - /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/gem
而安装2.3.0版本没有问题

issues链接：
https://github.com/CocoaPods/CocoaPods/issues/7765