[PATCH] add `tag:' prefix to `--output=tags' results

[Pieter Praet]

Alter `do_search_tags()' to prepend each result with `tag:',
and update affected test.

This makes its output consistent with `do_search_threads()' and
`do_search_messages()'.

See this discussion: id:"871v6b79s0.fsf at yoom.home.cworth.org"

Signed-off-by: Pieter Praet <pieter at praet.org>
---
 notmuch-search.c   |    2 +-
 test/search-output |    8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/notmuch-search.c b/notmuch-search.c
index faccaf7..5b91a40 100644
--- a/notmuch-search.c
+++ b/notmuch-search.c
@@ -364,7 +364,7 @@ do_search_tags (notmuch_database_t *notmuch,
 	if (! first_tag)
 	    fputs (format->item_sep, stdout);
 
-	format->item_id (tags, "", tag);
+	format->item_id (tags, "tag:", tag);
 
 	first_tag = 0;
     }
diff --git a/test/search-output b/test/search-output
index 10291c3..37f1b3d 100755
--- a/test/search-output
+++ b/test/search-output
@@ -289,10 +289,10 @@ test_expect_equal_file OUTPUT EXPECTED
 test_begin_subtest "--output=tags"
 notmuch search --output=tags '*' >OUTPUT
 cat <<EOF >EXPECTED
-attachment
-inbox
-signed
-unread
+tag:attachment
+tag:inbox
+tag:signed
+tag:unread
 EOF
 test_expect_equal_file OUTPUT EXPECTED
 
-- 
1.7.4.1