Execute (Initialize test environment):
  Save &rtp, g:plug_home, $MYVIMRC

  let vader = fnamemodify(globpath(&rtp, 'autoload/vader.vim'), ':h:h')
  let plug  = fnamemodify(globpath(&rtp, 'autoload/plug.vim'), ':h:h')
  set rtp=$HOME/.vim,$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after,$HOME/.vim/after
  execute 'set rtp^='.vader
  execute 'set rtp^='.plug
  let basertp = &rtp

  silent! unlet g:plugs
  silent! unlet g:plug_home

  set t_Co=256
  colo default

  let g:vimrc_reloaded = 0
  let vimrc    = tempname()
  call writefile(['let g:vimrc_reloaded += 1'], vimrc)
  let $MYVIMRC = vimrc

Execute (plug#begin() without path argument):
  call plug#begin()
  AssertEqual split(&rtp, ',')[0].'/plugged', g:plug_home
  unlet g:plug_home

Execute (plug#begin(path)):
  let temp_plugged = tempname()
  call plug#begin(temp_plugged.'/')
  Assert g:plug_home !~ '[/\\]$', 'Trailing / should be stripped from g:plug_home'

  AssertEqual 0, len(g:plugs)
  AssertEqual temp_plugged, g:plug_home
  AssertEqual basertp, &rtp

Execute (Subsequent plug#begin() calls will reuse g:plug_home):
  call plug#begin()
  AssertEqual temp_plugged, g:plug_home

Execute (Test Plug command):
  " Git repo with branch
  Plug 'junegunn/seoul256.vim', 'no-t_co'
  AssertEqual 'https://git:@github.com/junegunn/seoul256.vim.git', g:plugs['seoul256.vim'].uri
  AssertEqual join([temp_plugged, 'seoul256.vim/'], '/'), g:plugs['seoul256.vim'].dir
  AssertEqual 'no-t_co', g:plugs['seoul256.vim'].branch

  " Git URI
  Plug 'git@github.com:junegunn/vim-emoji.git'
  AssertEqual 'git@github.com:junegunn/vim-emoji.git', g:plugs['vim-emoji'].uri
  AssertEqual 'master', g:plugs['vim-emoji'].branch
  AssertEqual join([temp_plugged, 'vim-emoji/'], '/'), g:plugs['vim-emoji'].dir

  " vim-scripts/
  Plug 'beauty256'
  AssertEqual 'https://git:@github.com/vim-scripts/beauty256.git', g:plugs.beauty256.uri
  AssertEqual 'master', g:plugs.beauty256.branch

  AssertEqual 3, len(g:plugs)

Execute (Plug command with dictionary option):
  Plug 'junegunn/seoul256.vim', { 'branch': 'no-t_co', 'rtp': '././' }
  AssertEqual join([temp_plugged, 'seoul256.vim/'], '/'), g:plugs['seoul256.vim'].dir
  AssertEqual '././', g:plugs['seoul256.vim'].rtp

  AssertEqual 3, len(g:plugs)

Execute (PlugStatus before installation):
  PlugStatus
  AssertEqual 3, len(filter(getline(1, line('$')), 'v:val =~ "Not found"'))
  q

Execute (PlugClean before installation):
  PlugClean
  AssertEqual 1, len(filter(getline(1, line('$')), 'v:val =~ "Already clean"'))
  q

Execute (plug#end() updates &rtp):
  call plug#end()
  Assert len(&rtp) > len(basertp)

Execute (Yet, plugins are not available):
  Assert empty(globpath(&rtp, 'autoload/emoji.vim'))

Execute (PlugInstall):
  PlugInstall
  AssertEqual 1, g:vimrc_reloaded
  q

Execute (Plugin available after installation):
  Assert !empty(globpath(&rtp, 'autoload/emoji.vim'))

Execute (PlugClean after installation):
  PlugClean
  AssertEqual 1, len(filter(getline(1, line('$')), 'v:val =~ "Already clean"'))
  q

Execute (PlugStatus after installation):
  PlugStatus
  AssertEqual 3, len(filter(getline(1, line('$')), 'v:val =~ "OK"'))
  q

Execute (Change branch of seoul256.vim):
  call plug#begin()
  Plug 'junegunn/seoul256.vim'
  Plug 'git@github.com:junegunn/vim-emoji.git'
  call plug#end()

Execute (PlugStatus):
  PlugStatus
  %y
  q
  normal! P
  %sort
  g/^$/d

Expect:
  - seoul256.vim: (x) Invalid branch: no-t_co. Try PlugUpdate.
  - vim-emoji: OK
  Finished. 1 error(s).

# TODO: does not work due to inputsave()
# Do (PlugClean):
#   :PlugClean\<Enter>y\<Enter>
#   ggyG
#   q
#   PGdd

Execute (PlugClean! to remove seoul256.vim):
  PlugClean!
  AssertEqual 1, len(filter(getline(1, line('$')), 'v:val =~ "Removed"'))
  Assert empty(globpath(&rtp, 'colors/seoul256.vim'))
  Assert !empty(globpath(&rtp, 'autoload/emoji.vim'))
  q

Execute (Change GIT URI of vim-emoji):
  call plug#begin()
  Plug 'junegunn/seoul256.vim'
  Plug 'junegunn/vim-emoji'
  call plug#end()

Execute (PlugStatus):
  PlugStatus
  %y
  q
  normal! P
  %sort
  g/^$/d

Expect:
  - seoul256.vim: (x) Not found. Try PlugInstall.
  - vim-emoji: (x) Invalid remote: git@github.com:junegunn/vim-emoji.git. Try PlugClean.
  Finished. 2 error(s).

Execute (PlugClean! to remove vim-emoji):
  PlugClean!
  AssertEqual 1, len(filter(getline(1, line('$')), 'v:val =~ "Removed"'))
  Assert empty(globpath(&rtp, 'colors/seoul256.vim'))
  Assert empty(globpath(&rtp, 'autoload/emoji.vim'))
  q

Execute (PlugUpdate to install both again):
  PlugUpdate
  AssertEqual 2, len(filter(getline(1, line('$')), 'v:val =~ "Cloning into"'))
  AssertEqual 2, g:vimrc_reloaded
  Assert !empty(globpath(&rtp, 'colors/seoul256.vim')), 'seoul256.vim should be found'
  Assert !empty(globpath(&rtp, 'autoload/emoji.vim')), 'vim-emoji should be found'
  q

Execute (PlugUpdate only to find out plugins are up-to-date):
  PlugUpdate
  AssertEqual 2, len(filter(getline(1, line('$')), 'v:val =~ "Already up-to-date"'))
  AssertEqual 3, g:vimrc_reloaded
  q

Execute (Cleanup):
  call system('rm -rf '.temp_plugged)

  unlet g:plugs
  unlet g:plug_home
  unlet g:vimrc_reloaded
  unlet temp_plugged vader plug basertp

  Restore
  source $MYVIMRC