Re: [PATCH 5/5] completion: fix completion of certain aliases

[Junio C Hamano <gitster@pobox.com>]

Felipe Contreras <felipe.contreras@gmail.com> writes:

> Some commands need the first word to determine the actual action that is
> being executed, however, the command is wrong when we use an alias, for
> example 'alias.p=push', if we try to complete 'git p origin ', the
> result would be wrong because __git_complete_remote_or_refspec() doesn't
> know where it come from.
>
> So let's override words[1], so the alias 'p' is override by the actual
> command, 'push'.
>
> Reported-by: Aymeric Beaumet <aymeric.beaumet@gmail.com>
> Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
> ---

Does "some commands" above refer to anything that uses
__git_complete_remote_or_refspec, or is the set of commands larger
than that?

I am wondering if it is safer to introduce a new "local" variable
that is set by the caller of __git_complete_remote_or_refspec and
inspected by __git_complete_remote_or_refspec (instead of words[1])
to communiate the real name of the git subcommand being completed,
without touching words[] in place.

That way, we wouldn't have to worry about all the other references
of words[c], words[i], words[CURRENT] etc. in the script seeing the
word that the end-user did not type and did not actually appear on
the command line.

But perhaps we muck with the contents of words[] in a similar way in
many different places in the existing completion code often enough
that such an attempt not to touch the words[] array does not buy us
much safety anyway.  I didn't check (and that is why I am asking
with "I am wondering...").

Thanks, will queue.

[Ram and Szeder CC'ed as they appear in shortlog for the past 12
months].

>  contrib/completion/git-completion.bash | 1 +
>  contrib/completion/git-completion.zsh  | 1 +
>  2 files changed, 2 insertions(+)
>
> diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
> index 9525343..893ae5d 100644
> --- a/contrib/completion/git-completion.bash
> +++ b/contrib/completion/git-completion.bash
> @@ -2547,6 +2547,7 @@ __git_main ()
>  
>  	local expansion=$(__git_aliased_command "$command")
>  	if [ -n "$expansion" ]; then
> +		words[1]=$expansion
>  		completion_func="_git_${expansion//-/_}"
>  		declare -f $completion_func >/dev/null && $completion_func
>  	fi
> diff --git a/contrib/completion/git-completion.zsh b/contrib/completion/git-completion.zsh
> index 6b77968..9f6f0fa 100644
> --- a/contrib/completion/git-completion.zsh
> +++ b/contrib/completion/git-completion.zsh
> @@ -104,6 +104,7 @@ __git_zsh_bash_func ()
>  
>  	local expansion=$(__git_aliased_command "$command")
>  	if [ -n "$expansion" ]; then
> +		words[1]=$expansion
>  		completion_func="_git_${expansion//-/_}"
>  		declare -f $completion_func >/dev/null && $completion_func
>  	fi