add test

extra/redisotel/metrics.go

@@ -82,10 +82,15 @@ func InstrumentMetrics(rdb redis.UniversalClient, opts ...MetricsOption) error {
 	}
 }
 
+func poolStatsAttrs(conf *config) (poolAttrs, idleAttrs, usedAttrs attribute.Set) {
+	poolAttrs = attribute.NewSet(conf.attrs...)
+	idleAttrs = attribute.NewSet(append(poolAttrs.ToSlice(), attribute.String("state", "idle"))...)
+	usedAttrs = attribute.NewSet(append(poolAttrs.ToSlice(), attribute.String("state", "used"))...)
+	return
+}
+
 func reportPoolStats(rdb *redis.Client, conf *config) error {
-	poolAttrs := attribute.NewSet(conf.attrs...)
-	idleAttrs := attribute.NewSet(append(poolAttrs.ToSlice(), attribute.String("state", "idle"))...)
-	usedAttrs := attribute.NewSet(append(poolAttrs.ToSlice(), attribute.String("state", "used"))...)
+	poolAttrs, idleAttrs, usedAttrs := poolStatsAttrs(conf)
 
 	idleMax, err := conf.meter.Int64ObservableUpDownCounter(
 		"db.client.connections.idle.max",

extra/redisotel/metrics_test.go

@@ -0,0 +1,54 @@
+package redisotel
+
+import (
+	"reflect"
+	"testing"
+
+	"go.opentelemetry.io/otel/attribute"
+)
+
+func Test_poolStatsAttrs(t *testing.T) {
+	t.Parallel()
+	type args struct {
+		conf *config
+	}
+	tests := []struct {
+		name          string
+		args          args
+		wantPoolAttrs attribute.Set
+		wantIdleAttrs attribute.Set
+		wantUsedAttrs attribute.Set
+	}{
+		{
+			name: "#3122",
+			args: func() args {
+				conf := &config{
+					attrs: make([]attribute.KeyValue, 0, 4),
+				}
+				conf.attrs = append(conf.attrs, attribute.String("foo1", "bar1"), attribute.String("foo2", "bar2"))
+				conf.attrs = append(conf.attrs, attribute.String("pool.name", "pool1"))
+				return args{conf: conf}
+			}(),
+			wantPoolAttrs: attribute.NewSet(attribute.String("foo1", "bar1"), attribute.String("foo2", "bar2"),
+				attribute.String("pool.name", "pool1")),
+			wantIdleAttrs: attribute.NewSet(attribute.String("foo1", "bar1"), attribute.String("foo2", "bar2"),
+				attribute.String("pool.name", "pool1"), attribute.String("state", "idle")),
+			wantUsedAttrs: attribute.NewSet(attribute.String("foo1", "bar1"), attribute.String("foo2", "bar2"),
+				attribute.String("pool.name", "pool1"), attribute.String("state", "used")),
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotPoolAttrs, gotIdleAttrs, gotUsedAttrs := poolStatsAttrs(tt.args.conf)
+			if !reflect.DeepEqual(gotPoolAttrs, tt.wantPoolAttrs) {
+				t.Errorf("poolStatsAttrs() gotPoolAttrs = %v, want %v", gotPoolAttrs, tt.wantPoolAttrs)
+			}
+			if !reflect.DeepEqual(gotIdleAttrs, tt.wantIdleAttrs) {
+				t.Errorf("poolStatsAttrs() gotIdleAttrs = %v, want %v", gotIdleAttrs, tt.wantIdleAttrs)
+			}
+			if !reflect.DeepEqual(gotUsedAttrs, tt.wantUsedAttrs) {
+				t.Errorf("poolStatsAttrs() gotUsedAttrs = %v, want %v", gotUsedAttrs, tt.wantUsedAttrs)
+			}
+		})
+	}
+}