Re: [PATCH v5 3/3] completion: handle unusual characters for sparse-checkout

[Elijah Newren <newren@gmail.com>]

On Thu, Feb 3, 2022 at 12:44 PM Lessley Dennington via GitGitGadget
<gitgitgadget@gmail.com> wrote:
>
> From: Lessley Dennington <lessleydennington@gmail.com>
>
> Update the __gitcomp_directories method to de-quote and handle unusual
> characters in directory names. Although this initially involved an attempt
> to re-use the logic in __git_index_files, this method removed
> subdirectories (e.g. folder1/0/ became folder1/), so instead new custom
> logic was placed directly in the __gitcomp_directories method.
>
> Co-authored-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> Co-authored-by: Lessley Dennington <lessleydennington@gmail.com>
> Signed-off-by: Lessley Dennington <lessleydennington@gmail.com>
> ---
>  contrib/completion/git-completion.bash | 50 +++++++++++++-------------
>  t/t9902-completion.sh                  | 28 +++++++++++++++
>  2 files changed, 52 insertions(+), 26 deletions(-)
>
> diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
> index c5c8df6b6e5..c47e9ce09b2 100644
> --- a/contrib/completion/git-completion.bash
> +++ b/contrib/completion/git-completion.bash
> @@ -2988,32 +2988,30 @@ _git_show_branch ()
>
>  __gitcomp_directories ()
>  {
> -     local _tmp_dir _tmp_completions
> -
> -     # Get the directory of the current token; this differs from dirname
> -     # in that it keeps up to the final trailing slash.  If no slash found
> -     # that's fine too.
> -     [[ "$cur" =~ .*/ ]]
> -     _tmp_dir=$BASH_REMATCH
> -
> -     # Find possible directory completions, adding trailing '/' characters
> -     _tmp_completions="$(git ls-tree -d --name-only HEAD $_tmp_dir |
> -         sed -e s%$%/%)"
> -
> -     if [[ -n "$_tmp_completions" ]]; then
> -         # There were some directory completions, so find ones that
> -         # start with "$cur", the current token, and put those in COMPREPLY
> -         local i=0 c IFS=$' \t\n'
> -         for c in $_tmp_completions; do
> -             if [[ $c == "$cur"* ]]; then
> -                 COMPREPLY+=("$c")
> -             fi
> -         done
> -     elif [[ "$cur" =~ /$ ]]; then
> -         # No possible further completions any deeper, so assume we're at
> -         # a leaf directory and just consider it complete
> -         __gitcomp_direct_append "$cur "
> -     fi
> +       local _tmp_dir _tmp_completions _found=0
> +
> +       # Get the directory of the current token; this differs from dirname
> +       # in that it keeps up to the final trailing slash.  If no slash found
> +       # that's fine too.
> +       [[ "$cur" =~ .*/ ]]
> +       _tmp_dir=$BASH_REMATCH
> +
> +       # Find possible directory completions, adding trailing '/' characters,
> +       # de-quoting, and handling unusual characters.
> +       while IFS= read -r -d $'\0' c ; do
> +               # If there are directory completions, find ones that start
> +               # with "$cur", the current token, and put those in COMPREPLY
> +               if [[ $c == "$cur"* ]]; then
> +                       COMPREPLY+=("$c/")
> +                       _found=1
> +               fi
> +       done < <(git ls-tree -z -d --name-only HEAD $_tmp_dir)
> +
> +       if [[ $_found == 0 ]] && [[ "$cur" =~ /$ ]]; then
> +               # No possible further completions any deeper, so assume we're at
> +               # a leaf directory and just consider it complete
> +               __gitcomp_direct_append "$cur "
> +       fi

The indentation changes are distracting and make the patch harder to
review.  Could you either remove those, or apply the indentation
changes to patch 2 so that it starts with the right indentation?

I'm slightly surprised that __gitcomp_direct_append handles the
quoting for us, but the testcases below seem to cover it, so that's
cool.

Anyway, looks pretty clever to me; I was worried this was going to
require a much bigger change.

>  }
>
>  _git_sparse_checkout ()
> diff --git a/t/t9902-completion.sh b/t/t9902-completion.sh
> index b38a7302249..7f63d6057be 100755
> --- a/t/t9902-completion.sh
> +++ b/t/t9902-completion.sh
> @@ -1508,6 +1508,34 @@ test_expect_success 'cone mode sparse-checkout completes directory names' '
>         )
>  '
>
> +# use FUNNYNAMES to avoid running on Windows, which doesn't permit backslashes in paths
> +test_expect_success FUNNYNAMES 'cone mode sparse-checkout completes directory names with special characters' '
> +       # reset sparse-checkout
> +       git -C sparse-checkout sparse-checkout disable &&
> +       (
> +               cd sparse-checkout &&
> +               mkdir "directory with spaces" &&
> +               mkdir "$(printf "directory\twith\ttabs")" &&
> +               mkdir "directory\with\backslashes" &&
> +               mkdir "directory-with-áccent" &&
> +               >"directory with spaces/randomfile" &&
> +               >"$(printf "directory\twith\ttabs")/randomfile" &&
> +               >"directory\with\backslashes/randomfile" &&
> +               >"directory-with-áccent/randomfile" &&
> +               git add . &&
> +               git commit -m "Add directories containing unusual characters" &&
> +               git sparse-checkout set --cone "directory with spaces" \
> +                       "$(printf "directory\twith\ttabs")" "directory\with\backslashes" \
> +                       "directory-with-áccent" &&
> +               test_completion "git sparse-checkout add dir" <<-\EOF
> +               directory with spaces/
> +               directory       with    tabs/
> +               directory\with\backslashes/
> +               directory-with-áccent/
> +               EOF
> +       )
> +'

I'm glad you tested with lots of special characters -- spaces, tabs,
backslashes, and accents.  Newlines might also be nice, but probably
makes the test hard.  Anyway, looks good to me, other than the
indentation change.

> +
>  test_expect_success 'non-cone mode sparse-checkout uses bash completion' '
>         # reset sparse-checkout repo to non-cone mode
>         git -C sparse-checkout sparse-checkout disable &&
> --
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