Re: [PATCHv2 32/36] pathspec: allow querying for attributes

On Sat, Oct 29, 2016 at 1:54 AM, Stefan Beller [off-list ref] wrote:

The pathspec mechanism is extended via the new
":(attr:eol=input)pattern/to/match" syntax to filter paths so that it
requires paths to not just match the given pattern but also have the
specified attrs attached for them to be chosen.

Signed-off-by: Stefan Beller <redacted>
Signed-off-by: Junio C Hamano <redacted>
---
 Documentation/glossary-content.txt |  20 +++++
 dir.c                              |  35 ++++++++

Pathspec can be processed in a couple more places. The big two are
match_pathspec and tree_entry_interesting, the former traverses a list
while the latter does a tree. You don't have to implement attr
matching in tree_entry_interesting right now because nobody needs it,
probably. But you need to make sure if somebody accidentally calls
tree_entry_interesting with an attr pathspec, then it should
die("BUG"), not silently ignore attr.

The way to do that is GUARD_PATHSPEC macro which makes sure if only
recognized magic is allowed through. This macro guards all pathspec
processing functions. So you can add a new PATHSPEC_ATTR macro (or
some other name) to the "Pathspec magic" group near the beginning of
pathspec.h, set it whenever attr magic is present when you
parse_pathspec(), then lift the GUARD_PATHSPEC restriction in
match_pathspec() only because this function can handle it. Whenever
attr magic is used by any other functions, it will die() the way we
want.
-- 
Duy