first of all, you don’t need to add the script to the path, but you should source it in your .profile or .bashrc, like mentioned in the post.

Before pressing tab, make sure, that there is a whitespace after the grails command, so grails is recognized as a (complete) command, instead of the start of a file name!

Thanks. I added the script to my path–but all I get when typing grails [tab] [tab] is:

grails grails-bash-completion.sh grails-debug

whether I’m in a project directory or not.

hm, I propably created the bin directory in my home folder myself and added it to my $PATH in .bashrc. But you can put this script anywhere you want. The dircetory containing this script does not need to be in your $PATH, just make sure you include the script in your .bashrc or .profile as mentionend in the blog post.