func mustFindLogV2(t *testing.T, trc io.Reader, category string) trace.Event {
	r, err := trace.NewReader(trc)
	if err != nil {
		t.Fatalf("bad trace: %v", err)
	}
	var candidates []trace.Event
	for {
		ev, err := r.ReadEvent()
		if err == io.EOF {
			break
		}
		if err != nil {
			t.Fatalf("failed to parse trace: %v", err)
		}
		if ev.Kind() == trace.EventLog && ev.Log().Category == category {
			candidates = append(candidates, ev)

			{trace.EventRegionBegin, trace.BackgroundTask, []string{"post-existing region"}},
		}
		r, err := trace.NewReader(bytes.NewReader(tb))
		if err != nil {
			t.Error(err)
		}
		for {
			ev, err := r.ReadEvent()
			if err == io.EOF {
				break
			}
			if err != nil {
				t.Fatal(err)
			}
			for i, wantEv := range want {
				if wantEv.kind != ev.Kind() {
					continue
				}
				match := false

			emittedSync: true,
		}, nil
	default:
		return nil, fmt.Errorf("unknown or unsupported version go 1.%d", v)
	}
}

// ReadEvent reads a single event from the stream.
//
// If the stream has been exhausted, it returns an invalid
// event and io.EOF.
func (r *Reader) ReadEvent() (e Event, err error) {
	if r.go121Events != nil {
		ev, err := r.go121Events.next()
		if err != nil {

	var textTrace bytes.Buffer
	r, err := raw.NewReader(&trace)
	if err != nil {
		log.Fatalf("reading trace: %v", err)
	}
	w, err := raw.NewTextWriter(&textTrace, version.Current)
	for {
		ev, err := r.ReadEvent()
		if err == io.EOF {
			break
		}
		if err != nil {
			log.Fatalf("reading trace: %v", err)
		}
		if err := w.WriteEvent(ev); err != nil {
			log.Fatalf("writing trace: %v", err)
		}
	}

	// Create a reader.
	r, err := trace.NewReader(trc)
	if err != nil {
		t.Fatalf("failed to create trace reader for %s: %v", testPath, err)
	}
	// Process the trace.
	for {
		ev, err := r.ReadEvent()
		if err == io.EOF {
			break
		}
		if err != nil {
			t.Fatalf("failed to process trace %s: %v", testPath, err)
		}
		s.Event(&ev)
	}
	return s.Finalize()
}

		}
		var events []trace.Event
		tr, err := trace.NewReader(r)
		if err != nil {
			t.Fatalf("malformed test %s: bad trace file: %v", testPath, err)
		}
		for {
			ev, err := tr.ReadEvent()
			if err == io.EOF {
				break
			}
			if err != nil {
				t.Fatalf("malformed test %s: bad trace file: %v", testPath, err)
			}
			events = append(events, ev)
		}

	}
	var trace bytes.Buffer
	w, err := raw.NewWriter(&trace, r.Version())
	if err != nil {
		t.Fatalf("failed to write out test %s: %v", testPath, err)
	}
	for {
		ev, err := r.ReadEvent()
		if err == io.EOF {
			break
		}
		if err != nil {
			t.Fatalf("failed to read test %s: %v", testPath, err)
		}
		if err := w.WriteEvent(ev); err != nil {

	}
	r, err := traceparse.NewReader(stdOut)
	if err != nil {
		t.Fatalf("could not create trace.NewReader: %v", err)
	}
	var seen, seenSync bool
	i := 1
loop:
	for ; ; i++ {
		ev, err := r.ReadEvent()
		if err != nil {
			// We may have a broken tail to the trace -- that's OK.
			// We'll make sure we saw at least one complete generation.
			if err != io.EOF {
				t.Logf("error at event %d: %v", i, err)
			}

 * {@link DeadEvent} and reposted.
 *
 * <p>If a subscriber for a supertype of all events (such as Object) is registered, no event will
 * ever be considered dead, and no DeadEvents will be generated. Accordingly, while DeadEvent
 * extends {@link Object}, a subscriber registered to receive any Object will never receive a
 * DeadEvent.
 *
 * <p>This class is safe for concurrent use.
 *

 * {@link DeadEvent} and reposted.
 *
 * <p>If a subscriber for a supertype of all events (such as Object) is registered, no event will
 * ever be considered dead, and no DeadEvents will be generated. Accordingly, while DeadEvent
 * extends {@link Object}, a subscriber registered to receive any Object will never receive a
 * DeadEvent.
 *
 * <p>This class is safe for concurrent use.
 *