Re: [PATCH] Completion must sort before using uniq

> The uniq program only works with sorted input.  The man page states
> "uniq prints the unique lines in a sorted file".
>
> When __git_refs use the guess heuristic employed by checkout for
> tracking branches it wants to consider remote branches but only if
> the branch name is unique.  To do that, it calls 'uniq -u'.  However
> the input given to 'uniq -u' is not sorted.
>
> For example if all available branches are:
>   master
>   remotes/GitHub/maint
>   remotes/GitHub/master
>   remotes/origin/maint
>   remotes/origin/master
>
> When performing completion on 'git checkout ma' the choices given are
>   maint
>   master
> but when performing completion on 'git checkout mai', no choices
> appear, which is obviously contradictory.
>
> The reason is that, when dealing with 'git checkout ma',
> "__git_refs '' 1" will find the following list:
>   master
>   maint
>   master
>   maint
>   master
> which, when passed to 'uniq -u' will remain the same.
> But when dealing with 'git checkout mai', the list will be:
>   maint
>   maint
> which happens to be sorted and will be emptied by 'uniq -u'.
>
> The solution is to first call 'sort' and then 'uniq -u'.