go_use

If you need to switch between versions of go for different projects, things can be a hassle. If you use homebrew, that doesn't have to be a problem.

fbartho@fb-mbpro:~/Code/go_use$  go_use_12
Was using go12 (go version go1.2.2 darwin/amd64)
Unlinking /usr/local/Cellar/go12/1.2.2... 5 symlinks removed
Linking /usr/local/Cellar/go12/1.2.2... 5 symlinks created
Using go version go1.2.2 darwin/amd64 at /Users/fbartho/Code/gopath/go12
fbartho@fb-mbpro:~/Code/go_use$  echo $GOROOT; echo $GOPATH
/usr/local/Cellar/go12/1.2.2/libexec
/Users/fbartho/Code/gopath/go12
fbartho@fb-mbpro:~/Code/go_use$  go_use_14
Was using go12 (go version go1.2.2 darwin/amd64)
Unlinking /usr/local/Cellar/go12/1.2.2... 5 symlinks removed
Linking /usr/local/Cellar/go/1.4.2... 3 symlinks created
Using go version go1.4.2 darwin/amd64 at /Users/fbartho/Code/gopath/go
fbartho@fb-mbpro:~/Code/go_use$  echo $GOROOT; echo $GOPATH
/usr/local/Cellar/go/1.4.2/libexec
/Users/fbartho/Code/gopath/go

Also, if you're working in multiple shell windows, after switching which go is active, you'll want to run go_use_refresh in your other shells to update the environment.

Installation

1. First, install the go versions you want to use. Examples: brew install go brew install go12 (ignore warnings about linkage, of course they collide!)
2. Decide where you want the global go-paths for each version to be. (Edit GOPATHBASE in go_use_fixup_env for your environment). This keeps different go-versions of packages from clobbering each other.
3. Make sure to create the go-paths once you've decided. bin, pkg, src folders should be present in each.
4. Drop these scripts into a folder that is in your $PATH. (or link this folder into your PATH)
5. echo "go" > ~/.go_ver (this file stores the "current" choice of go version)
6. [Recommended] add the following to your bash .profile or .bash_login files. This will install the aliases to switch between versions and also load in the appropriate paths & roots into your shell's environment.

	source `which go_use_aliases`; go_use_refresh