[PATCH] gitignore: warn about pointless syntax

[Jan Engelhardt <jengelh@medozas.de>]

Add a warning to the gitignore parser if it sees "**". Git, using
fnmatch, does not consider the double-asterisk anything special like
rsync/zsh. Remind users of that, since too many seem to be Doing It
Wrong™.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
---
 dir.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/dir.c b/dir.c
index 0a78d00..60f65cb 100644
--- a/dir.c
+++ b/dir.c
@@ -376,6 +376,15 @@ void free_excludes(struct exclude_list *el)
 	el->excludes = NULL;
 }
 
+static inline void check_bogus_wildcard(const char *file, const char *p)
+{
+	if (strstr(p, "**") == NULL)
+		return;
+	warning(_("Pattern \"%s\" from file \"%s\": Double asterisk does not "
+		"have a special meaning and is interpreted just like a single "
+		"asterisk.\n"), file, p);
+}
+
 int add_excludes_from_file_to_list(const char *fname,
 				   const char *base,
 				   int baselen,
@@ -427,6 +436,7 @@ int add_excludes_from_file_to_list(const char *fname,
 		if (buf[i] == '\n') {
 			if (entry != buf + i && entry[0] != '#') {
 				buf[i - (i && buf[i-1] == '\r')] = 0;
+				check_bogus_wildcard(fname, entry);
 				add_exclude(entry, base, baselen, which);
 			}
 			entry = buf + i + 1;
-- 
1.7.7