Uma etapa adicional é necessária quando você instala um aplicativo GUI por meio do homebrew. Menciona brevemente isso durante o processo de instalação, mas é fácil perder.
brew install macvim
==> Downloading https://github.com/b4winckler/macvim/archive/snapshot-70.tar.gz
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==> ./configure --with-features=huge --enable-multibyte --with-macarchs=x86_64 --enable-perlinterp --enable-rubyinterp --enable-tclinterp --with-ruby-c
==> make
==> Caveats
MacVim.app installed to:
/usr/local/Cellar/macvim/7.4-70
To link the application to a normal Mac OS X location:
brew linkapps
or:
ln -s /usr/local/Cellar/macvim/7.4-70/MacVim.app /Applications
==> Summary