Re: .gitattributes override behavior (possible bug, or documentation bug)

From: Junio C Hamano <gitster@pobox.com>
Date: Mar 21, 2018, 16:18 UTC
Message-ID: <xmqqa7v1qu5o.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <CAHnyXxTf16ukf8CFSfzjQjTEjf5yJXFqK5TnS9KiXZEeAD7dgg@mail.gmail.com>

Dakota Hawkins <dakota@dakotahawkins.com> writes:

Show 12 quoted lines

> At any rate, would it at least be a good idea to make the "trailing
> slash halts recursion, won't consider nested .gitignore files"
> explicit in the `.gitignore` doc? Unless I'm missing it, I don't think
> that behavior is called out (or at least not called out concisely/in
> one place). It looks like this is all there is:
>
>     "If the pattern ends with a slash, it is removed for the purpose
> of the following description, but it would only find a match with a
> directory. In other words, foo/ will match a directory foo and paths
> underneath it, but will not match a regular file or a symbolic link
> foo (this is consistent with the way how pathspec works in general in
> Git)."

This is not saying "trailing slash halts" (and there is no need to say "trailing slash halts"---the rule is "directory is not recursed into"). The mention of '/' in the above paragraph is merely saying that we chose to use a trailing slash as a syntax to say "I want the path to match this pattern, but only when the path is a directory". In other words, if "D" (nothing else on the line) is on a line, it would match a file whose path is "D", but if you write "D/", it would not. It only would match a directory whose path is "D".

What "removed for the purpose of the following description" wants to say is about where in the path "D" in the above example can appear. Another rule after the paragraph would say that a pattern with a slash in it will match only at the current level, and a pattern with no slash would match in any level down below. Imagine an entry "D" and another entry "A/B" in .gitignore at the top-level of the project. The former has slash in it, the latter does not. These patterns match paths "D", "X/D", "A/B" but not "X/A/B". The first two match because the pattern "D" is not anchored with any slash, the last one does not match because the pattern "A/B" has a slash in it.

If the top-level .gitignore had "D/" and "A/B" in the above example, and paths "D" and "X/D" were both directories, the pattern "D/" still matches the directory "X/D", even though it is spelled with a slash in it. That slash is there merely for the purpose of marking the pattern to only match directories, and does not trigger "slash in a pattern anchors the pattern" rule, because it is "removed for the purpose of the following description".

> Also, I'm not sure what the "following description" is in "it is
> removed for the purpose of the following description". Is that trying
> to imply "excluded from the rest of the doc"?

See above.