Re: Change in .gitignore handling: intended or bug?

From: Junio C Hamano <gitster@pobox.com>
Date: Mar 10, 2016, 00:37 UTC
Message-ID: <xmqqd1r3f9rc.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <CACsJy8D=OjLBN-EXyKM4NnGhSGftYX+RAaR9fg8ML3QWAAb+iQ@mail.gmail.com>

Duy Nguyen <pclouds@gmail.com> writes:

Show 11 quoted lines

> A bit off topic, but these two paragraphs may need rephrasing, I don't
> really understand what it's trying to say
>
>  - If the pattern does not contain a slash '/', Git treats it as
>    a shell glob pattern and checks for a match against the
>    pathname relative to the location of the `.gitignore` file
>    (relative to the toplevel of the work tree if not from a
>    `.gitignore` file).
>
> Not sure why "relative to the location of .gitignore file" matters. We
> basically just take `basename $path` out and try to match it.

That is because the documentation was written with a single consistent matching mode in mind: you match various patterns against the FULL path in the repository, no matter where you find the path. If you find a pattern "*.c" in d/.gitignore file, a path d/hello.c matches, even though '*.c' does not match 'd/hello.c' in the shell glob sense, and the rule needs to clarify that the leading directory part "d/" in the path "d/hello.c" does not participate when matching it against the pattern "*.c" taken from "d/.gitignore" file.

If you start from a mindset to match hello.c part with *.c when you find both in d/ directory, "relative to the location" part would sound redundant or even confusing.

Show 9 quoted lines

>  - Otherwise, Git treats the pattern as a shell glob suitable
>    for consumption by fnmatch(3) with the FNM_PATHNAME flag:
>    wildcards in the pattern will not match a / in the pathname.
>    For example, "Documentation/{asterisk}.html" matches
>    "Documentation/git.html" but not "Documentation/ppc/ppc.html"
>    or "tools/perf/Documentation/perf.html".
>
> Perhaps "Otherwise" can be stated explicitly that "if the pattern does
> contain any slash, besides the trailing one".

Yeah, I think there originally was just two (it has slasn or it doesn't) and "If ..." followed by "Otherwise" was clear enough, but spellin it out would not hurt.