Fish shell's git prompt modified to support mercurial repos and bookmarks

fish_prompt.fish

function hg_prompt_update
        set -e -g __hg_branch
        set -e -g __hg_book
end

function fish_prompt --description 'Write out the prompt'
        
        set -l last_status $status

        # Just calculate these once, to save a few cycles when displaying the prompt
        if not set -q __fish_prompt_hostname
                set -g __fish_prompt_hostname (hostname|cut -d . -f 1)
        end

        if not set -q __fish_prompt_normal
                set -g __fish_prompt_normal (set_color normal)
        end
        
        if not set -q -g __fish_classic_git_functions_defined
                set -g __fish_classic_git_functions_defined

                function __fish_repaint_user --on-variable fish_color_user --description "Event handler, repaint when fish_color_user changes"
                        if status --is-interactive
                                set -e __fish_prompt_user
                                commandline -f repaint ^/dev/null
                        end
                end
                
                function __fish_repaint_host --on-variable fish_color_host --description "Event handler, repaint when fish_color_host changes"
                        if status --is-interactive
                                set -e __fish_prompt_host
                                commandline -f repaint ^/dev/null
                        end
                end
                
                function __fish_repaint_status --on-variable fish_color_status --description "Event handler; repaint when fish_color_status changes"
                        if status --is-interactive
                                set -e __fish_prompt_status
                                commandline -f repaint ^/dev/null
                        end
                end
        end

        set -l delim '>'

        switch $USER

        case root

                if not set -q __fish_prompt_cwd
                        if set -q fish_color_cwd_root
                                set -g __fish_prompt_cwd (set_color $fish_color_cwd_root)
                        else
                                set -g __fish_prompt_cwd (set_color $fish_color_cwd)
                        end
                end

        case '*'

                if not set -q __fish_prompt_cwd
                        set -g __fish_prompt_cwd (set_color $fish_color_cwd)
                end

        end

        set -l prompt_status
        if test $last_status -ne 0
                if not set -q __fish_prompt_status
                        set -g __fish_prompt_status (set_color $fish_color_status)
                end
                set prompt_status "$__fish_prompt_status [$last_status]$__fish_prompt_normal"
        end

        if not set -q __fish_prompt_user
                set -g __fish_prompt_user (set_color $fish_color_user)
        end
        if not set -q __fish_prompt_host
                set -g __fish_prompt_host (set_color $fish_color_host)
        end

#        echo -n -s "$__fish_prompt_user" "$USER" "$__fish_prompt_normal" @ "$__fish_prompt_host" "$__fish_prompt_hostname" "$__fish_prompt_normal" ' ' "$__fish_prompt_cwd" (prompt_pwd) (__fish_git_prompt) "$__fish_prompt_normal" "$prompt_status" "$delim" ' '

        if hg root >/dev/null 2>&1 
#               if not set -q -g __hg_branch
                        set -g __hg_branch (hg branch)
#               end
#               if not set -q -g __hg_book 
                        set -g __hg_book (hg book | grep \* | cut -d\  -f3)
#               end 
        else 
                hg_prompt_update
        end

        function hg_prompt
                set_color normal
                printf 'Mercurial: '
                set_color magenta
                printf '%s' $__hg_branch
                if  test -n "$__hg_book"
                        printf ' (%s)' $__hg_book
                end
                set_color normal
        end

        echo -n -s "$__fish_prompt_user" "$USER" "$__fish_prompt_normal" @ "$__fish_prompt_host" "$__fish_prompt_hostname" "$__fish_prompt_normal" ' ' "$__fish_prompt_cwd" (pwd | sed 's/\/home\/pgee/~/') 
        if set -q __hg_branch
#               echo -s  (__fish_git_prompt) (hg_prompt) "$__fish_prompt_normal" "$prompt_status" "$delim" ' '
                echo ' $'
                echo -s  (hg_prompt) "$__fish_prompt_normal" "$prompt_status" "$delim" ' '
        else
                echo -n -s (__fish_git_prompt) "$__fish_prompt_normal" "$prompt_status" "$delim" ' '
        end
end