Re: [PATCH v5] completion: add new __git_complete helper

[Felipe Contreras <felipe.contreras@gmail.com>]

On Mon, May 14, 2012 at 7:43 PM, Junio C Hamano <gitster@pobox.com> wrote:
> Felipe Contreras <felipe.contreras@gmail.com> writes:
>
>> This simplifies the completions, and would make it easier to define
>> aliases in the future.
>>
>> Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
>> ---
>>  contrib/completion/git-completion.bash |   70 +++++++++++++++-----------------
>>  t/t9902-completion.sh                  |    2 +-
>>  2 files changed, 34 insertions(+), 38 deletions(-)
>>
>> diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
>> index 9f56ec7..d60bb8a 100755
>> --- a/contrib/completion/git-completion.bash
>> +++ b/contrib/completion/git-completion.bash
>> @@ -2603,21 +2603,6 @@ _git ()
>>  {
>>       local i c=1 command __git_dir
>>
>> -     if [[ -n ${ZSH_VERSION-} ]]; then
>> -             emulate -L bash
>> -             setopt KSH_TYPESET
>> -
>> -             # workaround zsh's bug that leaves 'words' as a special
>> -             # variable in versions < 4.3.12
>> -             typeset -h words
>> -
>> -             # workaround zsh's bug that quotes spaces in the COMPREPLY
>> -             # array if IFS doesn't contain spaces.
>> -             typeset -h IFS
>> -     fi
>> -
>> -     local cur words cword prev
>> -     _get_comp_words_by_ref -n =: cur words cword prev
>>       while [ $c -lt $cword ]; do
>>               i="${words[c]}"
>>               case "$i" in
>> @@ -2667,22 +2652,6 @@ _git ()
>>
>>  _gitk ()
>>  {
>> -     if [[ -n ${ZSH_VERSION-} ]]; then
>> -             emulate -L bash
>> -             setopt KSH_TYPESET
>> -
>> -             # workaround zsh's bug that leaves 'words' as a special
>> -             # variable in versions < 4.3.12
>> -             typeset -h words
>> -
>> -             # workaround zsh's bug that quotes spaces in the COMPREPLY
>> -             # array if IFS doesn't contain spaces.
>> -             typeset -h IFS
>> -     fi
>> -
>> -     local cur words cword prev
>> -     _get_comp_words_by_ref -n =: cur words cword prev
>> -
>> @@ -2703,16 +2672,43 @@ _gitk ()
>>       __git_complete_revlist
>>  }
>>
>> -complete -o bashdefault -o default -o nospace -F _git git 2>/dev/null \
>> -     || complete -o default -o nospace -F _git git
>> -complete -o bashdefault -o default -o nospace -F _gitk gitk 2>/dev/null \
>> -     || complete -o default -o nospace -F _gitk gitk
>
> Nice code reduction by moving the duplicated code into the new helpers ;-)
>
>> +__git_func_wrap ()
>> +{
>> +     if [[ -n ${ZSH_VERSION-} ]]; then
>> +             emulate -L bash
>> +             setopt KSH_TYPESET
>> +
>> +             # workaround zsh's bug that leaves 'words' as a special
>> +             # variable in versions < 4.3.12
>> +             typeset -h words
>> +
>> +             # workaround zsh's bug that quotes spaces in the COMPREPLY
>> +             # array if IFS doesn't contain spaces.
>> +             typeset -h IFS
>> +     fi
>> +     local cur words cword prev
>> +     _get_comp_words_by_ref -n =: cur words cword prev
>> +     $1
>> +}
>> +
>> +# Setup completion for certain functions defined above by setting common
>> +# variables and workarounds.
>> +# This is NOT a public function; use at your own risk.
>> +__git_complete ()
>> +{
>> +     local wrapper="__git_wrap${2}"
>> +     eval "$wrapper () { __git_func_wrap $2 ; }"
>> +     complete -o bashdefault -o default -o nospace -F $wrapper $1 2>/dev/null \
>> +             || complete -o default -o nospace -F $wrapper $1
>> +}
>> +
>> +__git_complete git _git
>> +__git_complete gitk _gitk
>
> It makes my stomach queasy whenever I see $var not in double quotes that
> forces me to guess (and trace to verify if the codepath is what I really
> care about) if any value with $IFS in it could be used there, so even when
> they are known to be safe, I'd prefer to see either explicit quotes or
> comment that says what are expected in $1 and $2.

Which ones? These?

>> +     $1
>> +     complete -o bashdefault -o default -o nospace -F $wrapper $1 2>/dev/null \
>> +             || complete -o default -o nospace -F $wrapper $1

So you want:

  "$1"

  complete -o bashdefault -o default -o nospace -F "$wrapper" "$1" 2>/dev/null \
    || complete -o default -o nospace -F "$wrapper" "$1"

I wouldn't object to the arguments of complete, but the function call
seems totally unintuitive to me like that.

-- 
Felipe Contreras