From a7454ce5950e83caac9774ef32cc8979e5975f30 Mon Sep 17 00:00:00 2001
From: chanxuehong <chanxuehong@gmail.com>
Date: Fri, 13 Sep 2019 22:24:02 +0800
Subject: [PATCH] Improve noop impementation (#223)

---
 noop.go | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/noop.go b/noop.go
index 0d32f69..f9b680a 100644
--- a/noop.go
+++ b/noop.go
@@ -21,9 +21,9 @@ type noopSpan struct{}
 type noopSpanContext struct{}
 
 var (
-	defaultNoopSpanContext = noopSpanContext{}
-	defaultNoopSpan        = noopSpan{}
-	defaultNoopTracer      = NoopTracer{}
+	defaultNoopSpanContext SpanContext = noopSpanContext{}
+	defaultNoopSpan        Span        = noopSpan{}
+	defaultNoopTracer      Tracer      = NoopTracer{}
 )
 
 const (
@@ -35,7 +35,7 @@ func (n noopSpanContext) ForeachBaggageItem(handler func(k, v string) bool) {}
 
 // noopSpan:
 func (n noopSpan) Context() SpanContext                                  { return defaultNoopSpanContext }
-func (n noopSpan) SetBaggageItem(key, val string) Span                   { return defaultNoopSpan }
+func (n noopSpan) SetBaggageItem(key, val string) Span                   { return n }
 func (n noopSpan) BaggageItem(key string) string                         { return emptyString }
 func (n noopSpan) SetTag(key string, value interface{}) Span             { return n }
 func (n noopSpan) LogFields(fields ...log.Field)                         {}