Re: [RFC/PATCH] completion: avoid "words" as variable name for zsh portability

["SZEDER Gábor" <szeder@ira.uka.de>]

Hi,


On Wed, Apr 27, 2011 at 01:40:34AM -0500, Jonathan Nieder wrote:
> The "_get_comp_words_by_ref -n := words" command from the
> bash_completion library reassembles a modified version of COMP_WORDS
> with ':' and '=' no longer treated as word separators and stores it in
> the ${words[@]} array.  Git's programmable tab completion script uses
> this to abstract away the difference between bash v3's and bash v4's
> definitions of COMP_WORDS (bash v3 used shell words, while bash v4
> breaks at separator characters); see v1.7.4-rc0~11^2~2 (bash: get
> --pretty=m<tab> completion to work with bash v4, 2010-12-02).
> 
> zsh has (or rather its completion functions have) another idea about
> what ${words[@]} should contain: the array is prepopulated with the
> words from the command it is completing.  For reasons that are not
> well understood, when git-completion.bash reserves its own "words"
> variable with "local words", the variable becomes empty and cannot be
> changed from then on.  So the completion script neglects the arguments
> it has seen, and words complete like git subcommand names.  For
> example, typing "git log origi<TAB>" gives no completions because
> there are no "git origi..." commands.
> 
> Work around this by using a different variable (comp_words) that is
> not special to zsh.  So now commands that completed correctly before
> v1.7.4-rc0~11^2~2 on zsh should be able to complete correctly again.

Thanks for this explanation.  I tried to fix this some time ago, but
got only as far as to indentify that something is amiss with returning
$words from _get_comp_words_by_ref(), and during tracing I saw so much
weird and (for me) unexplicable zsh behavior that I simply gave up.

But this patch heavily conflicted with one of my long-forgotten
cleanup patch series, and that series together with the above
explanation gave me alternative ideas for fixing this issue with zsh.

So, here it is.  The first two patches are independent cleanups, but
they make the actual fix in the third patch so short.

It works well as far as I tested it with both bash and zsh, but I
would really appreciate a few extra sets of eyeballs for the cleanups
and sanity-checking and testing of the bugfix.


SZEDER Gábor (3):
  bash: don't modify the $cur variable in completion functions
  bash: remove unnecessary _get_comp_words_by_ref() invocations
  bash: don't declare 'local words' to make zsh happy

 contrib/completion/git-completion.bash |  225 +++++++++-----------------------
 1 files changed, 64 insertions(+), 161 deletions(-)