Merge pull request #45 from k1LoW/unuse-dg.ctxw

doneGroup.ctxw is not used anymore, so remove it.

donegroup.go

@@ -12,9 +12,7 @@ var ErrNotContainDoneGroup = errors.New("donegroup: context does not contain a d
 
 // doneGroup is cleanup function groups per Context.
 type doneGroup struct {
-	cancel context.CancelCauseFunc
-	// ctxw is the context used to call the cleanup functions
-	ctxw          context.Context
+	cancel        context.CancelCauseFunc
 	cleanupGroups []*sync.WaitGroup
 	errors        error
 	mu            sync.Mutex
@@ -178,17 +176,16 @@ func WaitWithContextAndKey(ctx, ctxw context.Context, key any) error {
 	if !ok {
 		return ErrNotContainDoneGroup
 	}
-	dg.mu.Lock()
-	dg.ctxw = ctxw
-	dg.mu.Unlock()
 	<-ctx.Done()
 	wg := &sync.WaitGroup{}
 	for _, g := range dg.cleanupGroups {
 		wg.Add(1)
+		dg.mu.Lock()
 		go func() {
 			g.Wait()
 			wg.Done()
 		}()
+		dg.mu.Unlock()
 	}
 	ch := make(chan struct{})
 	go func() {

donegroup_test.go

@@ -200,6 +200,7 @@ func TestNestedWithCancel(t *testing.T) {
 		thirdCancel()
 		<-thirdCtx.Done()
 
+		mu.Lock()
 		if firstCleanup != 0 {
 			t.Error("cleanup function for first called")
 		}
@@ -209,6 +210,7 @@ func TestNestedWithCancel(t *testing.T) {
 		if thirdCleanup != 0 {
 			t.Error("cleanup function for third called")
 		}
+		mu.Unlock()
 
 		secondCancel()
 		<-secondCtx.Done()
@@ -217,6 +219,7 @@ func TestNestedWithCancel(t *testing.T) {
 			t.Error(err)
 		}
 
+		mu.Lock()
 		if thirdCleanup != 3 {
 			t.Error("cleanup function for third not called")
 		}
@@ -226,6 +229,7 @@ func TestNestedWithCancel(t *testing.T) {
 		if firstCleanup != 0 {
 			t.Error("cleanup function for first called")
 		}
+		mu.Unlock()
 
 		firstCancel()
 		<-firstCtx.Done()
@@ -234,6 +238,7 @@ func TestNestedWithCancel(t *testing.T) {
 			t.Error(err)
 		}
 
+		mu.Lock()
 		if thirdCleanup != 3 {
 			t.Error("cleanup function for third not called")
 		}
@@ -243,6 +248,7 @@ func TestNestedWithCancel(t *testing.T) {
 		if firstCleanup != 10 {
 			t.Error("cleanup function for first not called")
 		}
+		mu.Unlock()
 	}()
 }