Bash completion + bower completion on mac.

Install bash-completion2 and nodejs:

brew install bash-completion2
brew install node

Add these lines to your .bash_profile:

if [[ -f $(brew --prefix)/share/bash-completion/bash_completion ]]; then
    . $(brew --prefix)/share/bash-completion/bash_completion
fi

Install bower:

npm install bower -g

Generate bower completion:

bower completion > /usr/local/share/bash-completion/completions/bower

Open new tab/window or just source .bash_profile