.

go/internal/xtracing/tracetest/tracetest.go

@@ -843,6 +843,7 @@ func Verify(t *testing.T, f func(t *T)) {
 	if len(trace0) < 2 {
 		return
 	}
+	streams0 := streamsOfTrace(trace0)
 
 	// sort trace0 by time just in case - events migth come from multiple
 	// CPUs simultaneously, and so for close events they might be added to
@@ -860,7 +861,7 @@ func Verify(t *testing.T, f func(t *T)) {
 		}
 	}
 
-	// retest f with 10·δtMax injected at i'th event
+	// retest f with 10·δtMax delay injected at i'th event	XXX 10x is too much?
 	for i := 0; i < len(trace0); i++ {
 		// stream and on-stream sequence number for i'th global event
 		stream := trace0[i].stream
@@ -875,22 +876,37 @@ func Verify(t *testing.T, f func(t *T)) {
 			tT := testf(t, map[string]*delayInjectState{
 				stream: &delayInjectState{
 					delayAt: istream,
-					delayT:  10*δtMax, // XXX make sure it < deadTime
+					delayT:  10*δtMax, // TODO make sure it < deadTime
 				},
 			})
 
-			// XXX in the end: verify that streams are the same from run to run (if completed successfully).
-			_ = tT
+			// verify that streams are the same from run to run
+			if tT.Failed() {
+				return
+			}
+			streams := streamsOfTrace(tT.tracev)
+			fmt.Printf("streams0: %v\n", streams0)
+			fmt.Printf("streams:  %v\n", streams)
+			if !reflect.DeepEqual(streams, streams0) {
+				tT.Fatalf("streams are not the same as in the first run:\n"+
+					  "first: %s\nnow:   %s\ndiff:\n%s\n\n",
+					  streams0, streams, pretty.Compare(streams0, streams))
+			}
 		})
-
 	}
 }
 
 
-/*
-// ---- misc ----
-
-func panicf(format string, argv ...interface{}) {
-	panic(fmt.Sprintf(format, argv...))
+// streamsOfTrace returns sorted list of all streams present in a trace.
+func streamsOfTrace(tracev []eventTrace) []string {
+	streams := make(map[string]struct{})
+	for _, t := range tracev {
+		streams[t.stream] = struct{}{}
+	}
+	streamv := []string{}
+	for stream := range streams {
+		streamv = append(streamv, stream)
+	}
+	sort.Strings(streamv)
+	return streamv
 }
-*/