Add information about the git repository you're in to Fish shell's prompt

config.fish

# Fish git prompt
set __fish_git_prompt_showdirtystate 'yes'
set __fish_git_prompt_showstashstate 'yes'
set __fish_git_prompt_showupstream 'yes'
set __fish_git_prompt_color_branch yellow

# Status Chars
set __fish_git_prompt_char_dirtystate '⚡'
set __fish_git_prompt_char_stagedstate '→'
set __fish_git_prompt_char_stashstate '↩'
set __fish_git_prompt_char_upstream_ahead '↑'
set __fish_git_prompt_char_upstream_behind '↓'

function fish_prompt
  set last_status $status

  set_color $fish_color_cwd
  printf '%s' (prompt_pwd)
  set_color normal

  printf '%s ' (__fish_git_prompt)

  set_color normal
end