No commands seem to work on Darwin with Neovim

No commands seem to work.

GoSetup does not seem to finish but I am sure all the commands are already in my $PATH.

Using neovim installed via homebrew:

$ nvim -v
NVIM v0.3.8
Build type: Release
LuaJIT 2.0.5
Compilation: /usr/local/Homebrew/Library/Homebrew/shims/mac/super/clang -Wconversion -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1 -DNDEBUG -DMIN_LOG_LEVEL=3 -Wall -Wextra -pedantic -Wno-unused-parameter -Wstrict-prototypes -std=gnu99 -Wimplicit-fallthrough -Wvla -fstack-protector-strong -fdiagnostics-color=auto -DINCLUDE_GENERATED_DECLARATIONS -D_GNU_SOURCE -DNVIM_MSGPACK_HAS_FLOAT32 -DNVIM_UNIBI_HAS_VAR_FROM -I/tmp/neovim-20190704-11886-1ukicoc/neovim-0.3.8/build/config -I/tmp/neovim-20190704-11886-1ukicoc/neovim-0.3.8/src -I/usr/local/include -I/usr/local/opt/gettext/include -I/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk/usr/include -I/tmp/neovim-20190704-11886-1ukicoc/neovim-0.3.8/build/src/nvim/auto -I/tmp/neovim-20190704-11886-1ukicoc/neovim-0.3.8/build/include
Compiled by brew@Mojave.local

Features: +acl +iconv +jemalloc +tui
See ":help feature-compile"

   system vimrc file: "$VIM/sysinit.vim"
  fall-back for $VIM: "/usr/local/Cellar/neovim/0.3.8/share/nvim"

Using Go installed via homebrew:

$ go version
go version go1.12.7 darwin/amd64

GoDiag fails with the following (as does GoCoverage):

:GoDiag                       Error detected while processing function gopher#diag#do[18]..gopher#system#run[8]..gopher#system#sanitize_cmd[1]..<lambda>8:
line    1:
E121: Undefined variable: v:none
E15: Invalid expression: l:v isnot v:none

My `~/.config/nvim/init.vim

call plug#begin('~/.config/nvim/plugged')
Plug 'arp242/gopher.vim'
call plug#end()

arp242 / gopher.vim

No commands seem to work on Darwin with Neovim #9