diff --git a/metadata/metadata.go b/metadata/metadata.go
index e910f9a8..adebc38f 100644
--- a/metadata/metadata.go
+++ b/metadata/metadata.go
@@ -92,7 +92,7 @@ func New(m map[string]string) MD {
 	md := MD{}
 	for k, v := range m {
 		key, val := encodeKeyValue(k, v)
-		md[key] = append(md[key],val)
+		md[key] = append(md[key], val)
 	}
 	return md
 }
@@ -111,7 +111,7 @@ func Pairs(kv ...string) MD {
 			continue
 		}
 		key, val := encodeKeyValue(k, s)
-		md[key] = append(md[key],val)
+		md[key] = append(md[key], val)
 	}
 	return md
 }
@@ -126,7 +126,7 @@ func (md MD) Copy() MD {
 	out := MD{}
 	for k, v := range md {
 		for _, i := range v {
-			out[k] = append(out[k],i)
+			out[k] = append(out[k], i)
 		}
 	}
 	return out
diff --git a/test/end2end_test.go b/test/end2end_test.go
index 5696153c..761f25a1 100644
--- a/test/end2end_test.go
+++ b/test/end2end_test.go
@@ -76,8 +76,8 @@ func (s *testServer) EmptyCall(ctx context.Context, in *testpb.Empty) (*testpb.E
 			return nil, grpc.Errorf(codes.DataLoss, "got extra metadata")
 		}
 		var str []string
-		for _,entry := range md["user-agent"]{
-			str = append(str,"ua",entry)	
+		for _, entry := range md["user-agent"] {
+			str = append(str, "ua", entry)
 		}
 		grpc.SendHeader(ctx, metadata.Pairs(str...))
 	}