.

go/internal/xtracing/tracetest/example_test.go

@@ -106,7 +106,7 @@ func TestTracetestExample(t *testing.T) {
 		}()
 
 		// assert that events come as expected
-		t.Expect("t2", eventHello("T1·C"))
+		t.Expect("t2", eventHello("T2·C"))
 		t.Expect("t1", eventHi("T1·A"))
 		t.Expect("t1", eventHello("T1·B"))
 

go/internal/xtracing/tracetest/tracetest.go

@@ -523,12 +523,16 @@ func (t *T) SetEventRouter(routeEvent func(event interface{}) (stream string)) {
 
 // XXX doc; naming
 func (t *T) RxEvent(event interface{}) {
+	stream := "default"
 	t.streamTabMu.Lock()
-	ch := t.chanForEvent(event)
+	if t.routeEvent != nil {
+		stream = t.routeEvent(event)
+	}
+	ch := t.chanForStream(stream)
 	t.streamTabMu.Unlock()
 
 	if ch == nil {
-		t.fatalfInNonMain("test failed")
+		t.fatalfInNonMain("%s: send: canceled (test failed)", stream)
 	}
 
 	// TODO it is possible to empirically detect here if a test incorrectly
@@ -563,6 +567,7 @@ func (t *T) RxEvent(event interface{}) {
 	ch.Send(event)
 }
 
+/*
 // chanForEvent returns channel corresponding to stream where event has to be delivered.
 // must be called under streamTabMu.
 func (t *T) chanForEvent(event interface{}) Chan {
@@ -572,6 +577,7 @@ func (t *T) chanForEvent(event interface{}) Chan {
 	}
 	return t.chanForStream(stream)
 }
+*/
 
 // chanForStream returns channel corresponding to stream.
 // must be called under streamTabMu.
@@ -790,7 +796,7 @@ func (t *T) FailNow() {
 		__.msg.nak(__.why)
 	}
 	for _, __ := range sendv {
-		__.msg.nak("test failed") // XXX reason can be custom / different
+		__.msg.nak("canceled (test failed)") // XXX reason can be custom / different
 	}
 	// in any case close channel where future Sends may arrive so that will "panic" too.
 	for _, ch := range streamTab {