Errors when installing cocoapods with gem

Question

I am using macOS Mojave and when I try to install cocoapods using gem I am getting the following error.

Building native extensions. This could take a whi

Answer 1

1. Run

   ruby -rrbconfig -e 'puts RbConfig::CONFIG["rubyhdrdir"]'
   

   to figure out your ruby configuration.
2. If the output is a nonexistent MacOSX10.15 path. Like

   /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/include/ruby-2.3.0
   

   then you should correct the configuration by doing next step.
3. Run

   sudo xcode-select --switch /Library/Developer/CommandLineTools
   

4. You can run

   ruby -rrbconfig -e 'puts RbConfig::CONFIG["rubyhdrdir"]'
   

   again to see if the path has changed.
5. The output should be something like

   /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/include/ruby-2.3.0
   

Now you can run gem install to install cocoapods!