fix race

testutil/accumulator.go

@@ -55,6 +55,8 @@ func (a *Accumulator) NMetrics() uint64 {
 }
 
 func (a *Accumulator) GetTelegrafMetrics() []telegraf.Metric {
+	a.Lock()
+	defer a.Unlock()
 	metrics := []telegraf.Metric{}
 	for _, m := range a.Metrics {
 		metrics = append(metrics, FromTestMetric(m))
@@ -251,6 +253,8 @@ func (a *Accumulator) SetDebug(debug bool) {
 
 // Get gets the specified measurement point from the accumulator
 func (a *Accumulator) Get(measurement string) (*Metric, bool) {
+	a.Lock()
+	defer a.Unlock()
 	for _, p := range a.Metrics {
 		if p.Measurement == measurement {
 			return p, true
@@ -261,6 +265,8 @@ func (a *Accumulator) Get(measurement string) (*Metric, bool) {
 }
 
 func (a *Accumulator) HasTag(measurement string, key string) bool {
+	a.Lock()
+	defer a.Unlock()
 	for _, p := range a.Metrics {
 		if p.Measurement == measurement {
 			_, ok := p.Tags[key]
@@ -271,6 +277,8 @@ func (a *Accumulator) HasTag(measurement string, key string) bool {
 }
 
 func (a *Accumulator) TagSetValue(measurement string, key string) string {
+	a.Lock()
+	defer a.Unlock()
 	for _, p := range a.Metrics {
 		if p.Measurement == measurement {
 			v, ok := p.Tags[key]
@@ -283,6 +291,8 @@ func (a *Accumulator) TagSetValue(measurement string, key string) string {
 }
 
 func (a *Accumulator) TagValue(measurement string, key string) string {
+	a.Lock()
+	defer a.Unlock()
 	for _, p := range a.Metrics {
 		if p.Measurement == measurement {
 			v, ok := p.Tags[key]
@@ -323,13 +333,13 @@ func (a *Accumulator) NFields() int {
 // Wait waits for the given number of metrics to be added to the accumulator.
 func (a *Accumulator) Wait(n int) {
 	a.Lock()
+	defer a.Unlock()
 	if a.Cond == nil {
 		a.Cond = sync.NewCond(&a.Mutex)
 	}
 	for int(a.NMetrics()) < n {
 		a.Cond.Wait()
 	}
-	a.Unlock()
 }
 
 // WaitError waits for the given number of errors to be added to the accumulator.