Re: [PATCH] doc/gitattributes: mention non-recursive behavior

From: Duy Nguyen <pclouds@gmail.com>
Date: Mar 20, 2018, 16:41 UTC
Message-ID: <CACsJy8CpwtNfp9oQGvECBuWGcwLEKK609iPJVEiXH4cDD6mpEg@mail.gmail.com>
In-Reply-To: <20180320041454.GA15213@sigill.intra.peff.net>

On Tue, Mar 20, 2018 at 5:14 AM, Jeff King <peff@peff.net> wrote:

Show 53 quoted lines

> On Tue, Mar 20, 2018 at 12:04:11AM -0400, Jeff King wrote:
>
>> > I guess my takeaway is that it would be _good_ if the gitattributes
>> > documentation contained the caveat about not matching directories
>> > recursively, but _great_ if gitattributes and gitignore (and whatever
>> > else there is) were consistent.
>>
>> I agree it would be nice if they were consistent (and pathspecs, too).
>> But unfortunately at this point there's a maze of backwards
>> compatibility to deal with.
>
> So let's not forget to do the easy half there. Here's a patch.
>
> -- >8 --
> Subject: [PATCH] doc/gitattributes: mention non-recursive behavior
>
> The gitattributes documentation claims that the pattern
> rules are largely the same as for gitignore. However, the
> rules for recursion are different.
>
> In an ideal world, we would make them the same (if for
> nothing else than consistency and simplicity), but that
> would create backwards compatibility issues. For some
> discussion, see this thread:
>
>   https://public-inbox.org/git/slrnkldd3g.1l4.jan@majutsushi.net/
>
> But let's at least document the differences instead of
> actively misleading the user by claiming that they're the
> same.
>
> Signed-off-by: Jeff King <peff@peff.net>
> ---
>  Documentation/gitattributes.txt | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
> index d52b254a22..1094fe2b5b 100644
> --- a/Documentation/gitattributes.txt
> +++ b/Documentation/gitattributes.txt
> @@ -56,9 +56,16 @@ Unspecified::
>
>  When more than one pattern matches the path, a later line
>  overrides an earlier line.  This overriding is done per
> -attribute.  The rules how the pattern matches paths are the
> -same as in `.gitignore` files; see linkgit:gitignore[5].
> -Unlike `.gitignore`, negative patterns are forbidden.
> +attribute.
> +
> +The rules by which the pattern matches paths are the same as in
> +`.gitignore` files (see linkgit:gitignore[5]), with a few exceptions:
> +
> +  - negative patterns are forbidden

After 8b1bd02415 (Make !pattern in .gitattributes non-fatal - 2013-03-01) maybe we could use the verb "ignored" too instead of "forbidden"

> +
> +  - patterns that match a directory do not recursively match paths
> +    inside that directory (so using the trailing-slash `path/` syntax is

Technically gitignore does not match paths inside either. It simply ignores the whole dir and not traverse in (which is more of an optimization than anything). That is coincidentally perceived as recursively ignoring. Anyway yes it's good to spell out the differences here for gitattributes.

> +    pointless in an attributes file; use `path/**` instead)

We probably could do this internally too (converting "path/" to "path/**") but we need to deal with corner cases (e.g. "path" without the trailing slash, but is a directory). So yes, suggesting the user to do it instead may be easier.

Show 6 quoted lines

>
>  When deciding what attributes are assigned to a path, Git
>  consults `$GIT_DIR/info/attributes` file (which has the highest
> --
> 2.17.0.rc0.402.ged0b3fd1ee
>

-- 
Duy