diff --git a/internal/app/app.go b/internal/app/app.go
index 6572186b..2a931703 100644
--- a/internal/app/app.go
+++ b/internal/app/app.go
@@ -148,7 +148,8 @@ func (app *App) saveText(filename string, m *slackdump.Conversation) error {
 	return m.ToText(app.sd, f)
 }
 
-// listEntities queries lists the supported entities, and writes the output to output.
+// listEntities queries lists the supported entities, and writes the output to
+// the output defined in the app.cfg.
 func (app *App) listEntities(ctx context.Context) error {
 	f, err := createFile(app.cfg.Output.Filename)
 	if err != nil {
@@ -207,7 +208,7 @@ func (app *App) fetchEntity(ctx context.Context, listFlags ListFlags) (rep slack
 	return
 }
 
-// formatEntity formats the entity according to output specification.
+// formatEntity formats the entity according to output parameter value.
 func (app *App) formatEntity(w io.Writer, rep slackdump.Reporter, output Output) error {
 	switch output.Format {
 	case OutputTypeText:
diff --git a/internal/app/timevalue.go b/internal/app/timevalue.go
index 387f6d7b..bcef015b 100644
--- a/internal/app/timevalue.go
+++ b/internal/app/timevalue.go
@@ -17,7 +17,7 @@ func (tv *TimeValue) Set(s string) error {
 	if s == "" {
 		return nil
 	}
-	if t, err := time.Parse(s, timeFmt); err != nil {
+	if t, err := time.Parse(timeFmt, s); err != nil {
 		return err
 	} else {
 		*tv = TimeValue(t)
diff --git a/internal/app/timevalue_test.go b/internal/app/timevalue_test.go
new file mode 100644
index 00000000..b0b57d0e
--- /dev/null
+++ b/internal/app/timevalue_test.go
@@ -0,0 +1,43 @@
+package app
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func tv(t time.Time) *TimeValue {
+	tv := TimeValue(t)
+	return &tv
+}
+
+func TestTimeValue_Set(t *testing.T) {
+	type args struct {
+		s string
+	}
+	tests := []struct {
+		name     string
+		tv       *TimeValue
+		args     args
+		wantTime *TimeValue
+		wantErr  bool
+	}{
+		{
+			"valid value",
+			&TimeValue{},
+			args{"2009-09-16T20:30:40"},
+			tv(time.Date(2009, 9, 16, 20, 30, 40, 0, time.UTC)),
+			false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			tv := &TimeValue{}
+			if err := tv.Set(tt.args.s); (err != nil) != tt.wantErr {
+				t.Errorf("TimeValue.Set() error = %v, wantErr %v", err, tt.wantErr)
+			}
+			assert.Equal(t, tt.wantTime, tv)
+		})
+	}
+}