Fix panic that occurs when an unexported time.Time is rendered.

I've also added tests for each of the filter types introduced in v0.3.4 to
ensure they all work correctly when applied to unexported fields.

sync_test.go

@@ -25,6 +25,17 @@ func TestPrinter_SyncFilter(t *testing.T) {
 	)
 	w.Unlock()
 
+	test(
+		t,
+		"sync.Mutex (unexported struct field)",
+		struct {
+			w sync.Mutex
+		}{},
+		"{",
+		"    w: sync.Mutex(<unlocked>)",
+		"}",
+	)
+
 	var rw sync.RWMutex
 
 	test(
@@ -75,6 +86,17 @@ func TestPrinter_SyncFilter(t *testing.T) {
 	<-barrier
 	rw.Unlock()
 
+	test(
+		t,
+		"sync.RWMutex (unexported struct field)",
+		struct {
+			rw sync.RWMutex
+		}{},
+		"{",
+		"    rw: sync.RWMutex(<unlocked>)",
+		"}",
+	)
+
 	var o sync.Once
 	test(
 		t,
@@ -106,4 +128,15 @@ func TestPrinter_SyncFilter(t *testing.T) {
 		"    once: <pending>",
 		"}",
 	)
+
+	test(
+		t,
+		"sync.Once (unexported struct field)",
+		struct {
+			o sync.Once
+		}{},
+		"{",
+		"    o: sync.Once(<pending>)",
+		"}",
+	)
 }

time.go

@@ -21,16 +21,16 @@ var (
 func TimeFilter(w io.Writer, v Value) (n int, err error) {
 	defer must.Recover(&err)
 
-	if v.DynamicType != timeType {
-		return 0, nil
+	if v.DynamicType == timeType {
+		mv, ok := unsafereflect.MakeMutable(v.Value)
+		if ok {
+			s := mv.Interface().(time.Time).Format(time.RFC3339Nano)
+			n += must.WriteString(w, s)
+			return
+		}
 	}
 
-	s := v.Value.
-		Convert(timeType).
-		Interface().(time.Time).
-		Format(time.RFC3339Nano)
-
-	return must.WriteString(w, s), nil
+	return 0, nil
 }
 
 // DurationFilter is a filter that formats time.Duration values.

time_test.go

@@ -23,9 +23,20 @@ func TestPrinter_TimeFilter(t *testing.T) {
 		tm,
 		"2019-11-03T10:13:08.839511Z",
 	)
+
+	test(
+		t,
+		"time.Time (unexported struct field)",
+		struct {
+			t time.Time
+		}{tm},
+		"{",
+		"    t: 2019-11-03T10:13:08.839511Z",
+		"}",
+	)
 }
 
-func TestPrinter_TimeDuration(t *testing.T) {
+func TestPrinter_DurationFilter(t *testing.T) {
 	dur := 20 * time.Second
 
 	test(
@@ -34,4 +45,15 @@ func TestPrinter_TimeDuration(t *testing.T) {
 		dur,
 		"20s",
 	)
+
+	test(
+		t,
+		"time.Duration (unexported struct field)",
+		struct {
+			d time.Duration
+		}{dur},
+		"{",
+		"    d: 20s",
+		"}",
+	)
 }