Installing Go on OS X

tl;dr this are my notes for installing Go (Golang) on OS X using hombrew, adding command completions on ZSH, a single GOPATH and all around clean install.

Today we’ll install the Go programming language and dependencies using OS X Homebrew. Keep in mind that this is an specific OS X installation. If you need to install Go on Ubuntu you can follow this guide, after that you can just go on with this tutorial.

Installing Go

Our first and only step in the Homebrew installation department will be installing Mercurial (hg) version control along with go.

Mercurial is not a Go dependency within Homebrew, but, there are some specific packages/tools like go get that use it, so keep that in mind.

$ brew install hg go

This will install hg and Go with the --cross-compile-common flag. The cross compile common flag will build the language with cross-compilers and runtime support for darwin, linux and windows. If you want cross-compilers and runtime support for all Go supported platforms append --cross-compile-all flag to the installation command.

You can check the existing flags using brew info go.

Setting the GOPATH

For the go path, I prefer to use a unique/single one for all my projects and I like to have all packages within the ~/go directory. I’ll have to admit that I haven’t done anything complex in Go that deserves more than a single GOPATH; maybe I’ll have to bite my tongue later on, but, you know… It’s my current opinion. If you feel like a single GOPATH is not good for you it’s OK too.

I’ll recommend you read this article that explains why it’s a good idea to have a single GOPATH and when it’s not.

Enough talking, lets create our GOPATH directory and export to the environment:

$ mkdir ~/go
$ export GOPATH=$HOME/go
$ export PATH="$GOPATH/bin:$PATH"
$ export PATH="$PATH:/usr/local/opt/go/libexec/bin"

You can use any other directory for the GOPATH, but I found this is a common one within the community, so lets stick with this “convention”.

We are exporting the GOPATH, $GOPATH/bin and /usr/local/opt/go/libexec/bin directory to the $PATH to add any existing Go binaries and generated binaries automatically to our $PATH.

Set completions ZSH

As of Go 1.4, Google Removed the completions files for zsh and bash due to the lack of maintenance. The following will no longer work.

When installing Go with Homebrew all ZSH completions are thrown to the /usr/local/share/zsh/site-functions directory. If we have ZSH completions configured to grab completion.zsh files, we can just create a new completion.zsh file for Go and add this snippet:

completion="$(brew --prefix)/share/zsh/site-functions/go"

if test -f $completion
then
  source <(cat $completion)
fi

After restarting or reloading your shell session you’ll be able to tab complete the different Go CLI commands.

If you are a Bash user, there’s a Homebrew package that’s called bash-completion that will easily enable this functionality. You can check this comment on stackoverflow that shows how to install and configure the package.

If using Vim

If you are using Vim as your text editor I blindly recommend vim-go from fatih it’s a fantastic plugin, really really complete and well crafted, give it a Go, you’ll not regret it.

These are two resources that will shows you how to set Vim for Go development. Setting up Vim as your Go IDE, and Setup VIM for Go development