Re: [PATCH v3] config: correct '**' matching in includeIf patterns

[Jason Karns <jason.karns@gmail.com>]

On Tue, Mar 26, 2019 at 5:42 AM Nguyễn Thái Ngọc Duy <pclouds@gmail.com> wrote:
>
> The current wildmatch() call for includeIf's gitdir pattern does not
> pass the WM_PATHNAME flag. Without this flag, '*' is treated _almost_
> the same as '**' (because '*' also matches slashes) with one exception:
>
> '/**/' can match a single slash. The pattern 'foo/**/bar' matches
> 'foo/bar'.
>
> But '/*/', which is essentially what wildmatch engine sees without
> WM_PATHNAME, has to match two slashes (and '*' matches nothing). Which
> means 'foo/*/bar' cannot match 'foo/bar'. It can only match 'foo//bar'.
>
> The result of this is the current wildmatch() call works most of the
> time until the user depends on '/**/' matching no path component. And
> also '*' matches slashes while it should not, but people probably
> haven't noticed this yet. The fix is straightforward.
>
> Reported-by: Jason Karns <jason.karns@gmail.com>
> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
> ---
>  v3 updates the test to avoid mkdir and cd, and break long lines.
>
>  config.c                  |  2 +-
>  t/t1305-config-include.sh | 13 +++++++++++++
>  2 files changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/config.c b/config.c
> index 0f0cdd8c0f..c2846df3f1 100644
> --- a/config.c
> +++ b/config.c
> @@ -242,7 +242,7 @@ static int include_by_gitdir(const struct config_options *opts,
>         }
>
>         ret = !wildmatch(pattern.buf + prefix, text.buf + prefix,
> -                        icase ? WM_CASEFOLD : 0);
> +                        WM_PATHNAME | (icase ? WM_CASEFOLD : 0));
>
>         if (!ret && !already_tried_absolute) {
>                 /*
> diff --git a/t/t1305-config-include.sh b/t/t1305-config-include.sh
> index 635918505d..579a86b7f8 100755
> --- a/t/t1305-config-include.sh
> +++ b/t/t1305-config-include.sh
> @@ -229,6 +229,19 @@ test_expect_success 'conditional include, early config reading' '
>         )
>  '
>
> +test_expect_success 'conditional include with /**/' '
> +       REPO=foo/bar/repo &&
> +       git init $REPO &&
> +       cat >>$REPO/.git/config <<-\EOF &&
> +       [includeIf "gitdir:**/foo/**/bar/**"]
> +       path=bar7
> +       EOF
> +       echo "[test]seven=7" >$REPO/.git/bar7 &&
> +       echo 7 >expect &&
> +       git -C $REPO config test.seven >actual &&
> +       test_cmp expect actual
> +'
> +
>  test_expect_success SYMLINKS 'conditional include, set up symlinked $HOME' '
>         mkdir real-home &&
>         ln -s real-home home &&
> --
> 2.21.0.479.g47ac719cd3
>

Thank you all for looking into this! (and your work on git!) It is
very much appreciated.

Jason