Subject: Re: [PATCH 2/2] bash completion: Support "divergence from upstream" warnings in __git_ps1

From: SZEDER Gábor <[email-masked]>
Date: Sat, 12 Jun 2010 02:00:02 +0200

Hi,

On Thu, Jun 10, 2010 at 01:47:24PM +0200, Thomas Rast wrote:
> From: Andrew Sayers <[email-masked]>

> diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
> index de5e6c1..49253a1 100755
> --- a/contrib/completion/git-completion.bash
> +++ b/contrib/completion/git-completion.bash
> @@ -42,6 +42,14 @@
>  #       set GIT_PS1_SHOWUNTRACKEDFILES to a nonempty value. If there're
>  #       untracked files, then a '%' will be shown next to the branch name.
>  #
> +#       If you would like to see the difference bitween HEAD and its
> +#       upstream, set GIT_PS1_SHOWUPSTREAM to a nonempty value.  The
> +#       difference will be shown as, e.g., "u+7-5" meaning that you
> +#       are 7 commits ahead of and 5 commits behind the upstream.  You
> +#       can enable git-svn mode by setting GIT_PS1_SHOWUPSTREAM=svn
> +#       and set the value per-repository with the bash.showUpstream
> +#       variable.

I find the last sentence of this description ambiguous.  What value
should bash.showUpstream be set to?  Do I really need to set both
GIT_PS1_SHOWUPSTREAM and bash.showUpstream?  What if
GIT_PS1_SHOWUPSTREAM=foo and bash.showUpstream=svn?

Furthermore, I think it would be good to provide means to disable this
feature for some repositories while keeping it enabled for others.  In
the current version I could either disable or enable it globally.
Perhaps we could disable it when bash.showUpstream is set to an empty
value.

> +#
>  # To submit patches:
>  #
>  #    *) Read Documentation/SubmittingPatches
> @@ -132,6 +140,7 @@ __git_ps1 ()
>  		local s
>  		local u
>  		local c
> +		local p
>  
>  		if [ "true" = "$(git rev-parse --is-inside-git-dir 2>/dev/null)" ]; then
>  			if [ "true" = "$(git rev-parse --is-bare-repository 2>/dev/null)" ]; then
> @@ -159,10 +168,56 @@ __git_ps1 ()
>  			      u="%"
>  			   fi
>  			fi
> +
> +			if [ -n "${GIT_PS1_SHOWUPSTREAM-}" ]; then
> +
> +				# Note: 'p' is used as a temporary throughout this block,
> +				# before finally being assigned its correct value
> +

Back in the old days when I was just learning programming, I got my
ass kicked when I dared to reuse the same variable for different
purposes.  C'mon, just how much shorter it is to create one more
variable than this two lines long comment?! ;)  It could even be
squashed together with the "local upstream" line.

> +				if p="$(git config --get bash.showUpstream)"
> +				then
> +					GIT_PS1_SHOWUPSTREAM="$p"
> +				fi
> +
> +				local upstream
> +
> +				if [ "${GIT_PS1_SHOWUPSTREAM-}" = "svn" ]; then

No need to use default value here, because GIT_PS1_SHOWUPSTREAM has
already been set above.

> +
> +					# git-svn upstream checking
> +					p="$( git config --get svn-remote.svn.url )"
> +					upstream=( $( git log --first-parent -1 \
> +						--grep="^git-svn-id: $p" ) )
> +					upstream=${upstream[ ${#upstream[@]} - 2 ]}
> +					upstream=${upstream%@*}
> +					upstream=${upstream#*$p/}
> +

Unnecessary empty lines before and after this block of code.

> +				else # git upstream checking
> +					upstream="@{upstream}"
> +				fi
> +
> +				p=$(git rev-list --count --left-right "$upstream"...HEAD 2>/dev/null)
> +				debug_p="$p"

The leftover debugging mentioned by Michael.

> +				case "$p" in
> +				"0	0"|"") # empty means no --count support or no upstream
> +					p=
> +					;;
> +				"0	"*)
> +					p="+${p#0	}"
> +					;;
> +				*"	0")
> +					p="-${p%	0}"
> +					;;
> +				*)
> +					p="+${p#*	}-${p%	*}"
> +					;;
> +				esac
> +
> +			fi
> +
>  		fi

Unnecessary empty lines before both fi.

>  
>  		local f="$w$i$s$u"
> -		printf "${1:- (%s)}" "$c${b##refs/heads/}${f:+ $f}$r"
> +		printf "${1:- (%s)}" "$c${b##refs/heads/}${f:+ $f}$r${p:+ u$p}"
>  	fi
>  }
>  
> -- 
> 1.7.1.553.ge4d5c.dirty
> 
>