trace: disable additional trace output for unit tests

Some unit-tests use trace output to verify internal state, and unstable
output such as timestamps and line numbers are not useful there.

Disable additional trace output if GIT_TRACE_BARE is set.

Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/trace.c b/trace.c
index 3d02bcc..a194b16 100644
--- a/trace.c
+++ b/trace.c
@@ -87,11 +87,17 @@ static const char err_msg[] = "Could not trace into fd given by "
 
 static int prepare_trace_line(struct trace_key *key, struct strbuf *buf)
 {
+	static struct trace_key trace_bare = TRACE_KEY_INIT(BARE);
+
 	if (!trace_want(key))
 		return 0;
 
 	set_try_to_free_routine(NULL);	/* is never reset */
 
+	/* unit tests may want to disable additional trace output */
+	if (trace_want(&trace_bare))
+		return 1;
+
 	/* add line prefix here */
 
 	return 1;