Running pod setup gives me "bad interpreter: No such file or directory" error

I encountered this problem when upgrading to Mac OS High Sierra.

This was my fix:

sudo gem install cocoapods

I found this answer on the CocoaPods issue list on Github.

This happened when I upgraded to Catalina. I solved it by running:

sudo gem install -n /usr/local/bin ruby
sudo gem install -n /usr/local/bin cocoapods

After upgraded to High Sierra, I got the same error, just reinstalled the cocoapods

sudo gem install -n /usr/local/bin cocoapods