Extend unit test

internal/buffer/unbounded.go

@@ -86,7 +86,9 @@ func (b *Unbounded) Load() {
 //
 // Upon reading a value from this channel, users are expected to call Load() to
 // send the next buffered value onto the channel if there is any.
-// If the unbounded buffer is closed, a read channel returned by this method is closed.
+//
+// If the unbounded buffer is closed, the read channel returned by this method
+// is closed.
 func (b *Unbounded) Get() <-chan interface{} {
 	return b.c
 }

internal/buffer/unbounded_test.go

@@ -120,11 +120,18 @@ func (s) TestMultipleWriters(t *testing.T) {
 	}
 }
 
+// TestClose makes sure that the buffer is closed after calling Close().
 func (s) TestClose(t *testing.T) {
 	ub := NewUnbounded()
 	ub.Close()
+	if v, ok := <-ub.Get(); ok {
+		t.Errorf("Unbounded.Get() = %v, want closed channel", v)
+	}
 	ub.Put(1)
 	ub.Load()
+	if v, ok := <-ub.Get(); ok {
+		t.Errorf("Unbounded.Get() = %v, want closed channel", v)
+	}
 	ub.Close()
 	if v, ok := <-ub.Get(); ok {
 		t.Errorf("Unbounded.Get() = %v, want closed channel", v)

xds/internal/xdsclient/transport/transport.go

@@ -402,7 +402,7 @@ func (t *Transport) send(ctx context.Context) {
 			sendNodeProto = false
 		case u, ok := <-t.adsRequestCh.Get():
 			if !ok {
-				// No requests will be sent after the channel is closed.
+				// No requests will be sent after the unbounded buffer is closed.
 				return
 			}
 			t.adsRequestCh.Load()