run ResetForTest during cleanup (#2754)

Co-authored-by: Chester Cheung <[email protected]>

Author: dmathieu

internal/global/benchmark_test.go

@@ -25,7 +25,7 @@ import (
 func BenchmarkStartEndSpanNoSDK(b *testing.B) {
 	// Compare with BenchmarkStartEndSpan() in
 	// ../../sdk/trace/benchmark_test.go.
-	global.ResetForTest()
+	global.ResetForTest(b)
 	t := otel.Tracer("Benchmark StartEndSpan")
 	ctx := context.Background()
 	b.ResetTimer()

internal/global/propagator_test.go

@@ -23,7 +23,7 @@ import (
 )
 
 func TestTextMapPropagatorDelegation(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 	ctx := context.Background()
 	carrier := internaltest.NewTextMapCarrier(nil)
 
@@ -53,7 +53,7 @@ func TestTextMapPropagatorDelegation(t *testing.T) {
 }
 
 func TestTextMapPropagatorDelegationNil(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 	ctx := context.Background()
 	carrier := internaltest.NewTextMapCarrier(nil)
 
@@ -75,7 +75,7 @@ func TestTextMapPropagatorDelegationNil(t *testing.T) {
 }
 
 func TestTextMapPropagatorFields(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 	initial := global.TextMapPropagator()
 	delegate := internaltest.NewTextMapPropagator("test")
 	delegateFields := delegate.Fields()

internal/global/state.go

@@ -17,6 +17,7 @@ package global // import "go.opentelemetry.io/otel/internal/global"
 import (
 	"sync"
 	"sync/atomic"
+	"testing"
 
 	"go.opentelemetry.io/otel/propagation"
 	"go.opentelemetry.io/otel/trace"
@@ -97,10 +98,13 @@ func defaultPropagatorsValue() *atomic.Value {
 	return v
 }
 
-// ResetForTest restores the initial global state, for testing purposes.
-func ResetForTest() {
-	globalTracer = defaultTracerValue()
-	globalPropagators = defaultPropagatorsValue()
-	delegateTraceOnce = sync.Once{}
-	delegateTextMapPropagatorOnce = sync.Once{}
+// ResetForTest configures the test to restores the initial global state during
+// its Cleanup step
+func ResetForTest(t testing.TB) {
+	t.Cleanup(func() {
+		globalTracer = defaultTracerValue()
+		globalPropagators = defaultPropagatorsValue()
+		delegateTraceOnce = sync.Once{}
+		delegateTextMapPropagatorOnce = sync.Once{}
+	})
 }

internal/global/state_test.go

@@ -21,7 +21,7 @@ import (
 )
 
 func TestResetsOfGlobalsPanic(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 	tests := map[string]func(){
 		"SetTextMapPropagator": func() {
 			global.SetTextMapPropagator(global.TextMapPropagator())

internal/global/trace_test.go

@@ -44,7 +44,7 @@ func (fn fnTracer) Start(ctx context.Context, spanName string, opts ...trace.Spa
 }
 
 func TestTraceProviderDelegation(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 
 	// Map of tracers to expected span names.
 	expected := map[string][]string{
@@ -98,7 +98,7 @@ func TestTraceProviderDelegation(t *testing.T) {
 }
 
 func TestTraceProviderDelegates(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 
 	// Retrieve the placeholder TracerProvider.
 	gtp := otel.GetTracerProvider()
@@ -118,7 +118,7 @@ func TestTraceProviderDelegates(t *testing.T) {
 }
 
 func TestTraceProviderDelegatesConcurrentSafe(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 
 	// Retrieve the placeholder TracerProvider.
 	gtp := otel.GetTracerProvider()
@@ -161,7 +161,7 @@ func TestTraceProviderDelegatesConcurrentSafe(t *testing.T) {
 }
 
 func TestTracerDelegatesConcurrentSafe(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 
 	// Retrieve the placeholder TracerProvider.
 	gtp := otel.GetTracerProvider()
@@ -210,7 +210,7 @@ func TestTracerDelegatesConcurrentSafe(t *testing.T) {
 }
 
 func TestTraceProviderDelegatesSameInstance(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 
 	// Retrieve the placeholder TracerProvider.
 	gtp := otel.GetTracerProvider()
@@ -228,7 +228,7 @@ func TestTraceProviderDelegatesSameInstance(t *testing.T) {
 }
 
 func TestSpanContextPropagatedWithNonRecordingSpan(t *testing.T) {
-	global.ResetForTest()
+	global.ResetForTest(t)
 
 	sc := trace.NewSpanContext(trace.SpanContextConfig{
 		TraceID:    [16]byte{0x01},