Re: How do I qualify paths in the .gitignore file w.r.t. the repo root directory?

On 2009-02-24, Junio C Hamano <gitster@pobox.com> wrote:

[lots of very clear and detailed explanation snipped for brevity...]

I'd been sort of struggling with the part of 'man gitignore' that describes the rules for the exclusion patterns; it just didn't seem as clear as it could have been. It's very accurate, but I (and I noticed a few others on irc) had to read very carefully to do anything moderately complex.

A few days ago, 'doener' (Björn Steinbrink) came up with some much simpler rules that said the same thing, and -- building on the insight that his rules gave me -- I came up with these:

----->8-----

Note that rule 1 merely *modifies* rules 2 and 3, it does not supercede or preclude them.

1.  If you pattern ends with a slash, it matches only
    directories (and their contents)
2.  If there is no slash otherwise, it matches that name, at
    any depth in the tree
3.  If there is a slash anywhere else, it matches that name,
    relative to the .gitignore (or $GIT_WORK_TREE if the
    pattern is from one of the other pattern sources like
    `.git/info/exclude` etc)

The wildcards (`*` and `?`) do not match slashes, but otherwise the patterns are normal shell globs as defined by fnmatch(3) with the FNM_PATHNAME flag set.

----->8-----

Those rules are meant to clarify the following lines from the gitignore man page:

 - 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).

 - If the pattern does not contain a slash '/', git treats it as
   a shell glob pattern and checks for a match against the
   pathname without leading directories.

 - 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.