dir: hide untracked contents of untracked dirs

When we taught read_directory_recursive() to recurse into untracked
directories in search of ignored files given DIR_SHOW_IGNORED_TOO, that
had the side effect of teaching it to collect the untracked contents of
untracked directories. It doesn't always make sense to return these,
though (we do need them for `clean -d`), so we introduce a flag
(DIR_KEEP_UNTRACKED_CONTENTS) to control whether or not read_directory()
strips dir->entries of the untracked contents of untracked dirs.

We also introduce check_contains() to check if one dir_entry corresponds
to a path which contains the path corresponding to another dir_entry.

This also fixes known breakages in t7061, since status --ignored now
searches untracked directories for ignored files.

Signed-off-by: Samuel Lijin <sxlijin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/Documentation/technical/api-directory-listing.txt b/Documentation/technical/api-directory-listing.txt
index 7f8e78d..6c77b49 100644
--- a/Documentation/technical/api-directory-listing.txt
+++ b/Documentation/technical/api-directory-listing.txt
@@ -33,6 +33,12 @@ The notable options are:
 	Similar to `DIR_SHOW_IGNORED`, but return ignored files in `ignored[]`
 	in addition to untracked files in `entries[]`.
 
+`DIR_KEEP_UNTRACKED_CONTENTS`:::
+
+	Only has meaning if `DIR_SHOW_IGNORED_TOO` is also set; if this is set, the
+	untracked contents of untracked directories are also returned in
+	`entries[]`.
+
 `DIR_COLLECT_IGNORED`:::
 
 	Special mode for git-add. Return ignored files in `ignored[]` and