test: add batchMsg test

tea_test.go

@@ -7,8 +7,11 @@ import (
 	"time"
 )
 
+type incrementMsg struct{}
+
 type testModel struct {
 	executed atomic.Value
+	counter  atomic.Value
 }
 
 func (m testModel) Init() Cmd {
@@ -17,9 +20,18 @@ func (m testModel) Init() Cmd {
 
 func (m *testModel) Update(msg Msg) (Model, Cmd) {
 	switch msg.(type) {
+	case incrementMsg:
+		i := m.counter.Load()
+		if i == nil {
+			m.counter.Store(1)
+		} else {
+			m.counter.Store(i.(int) + 1)
+		}
+
 	case KeyMsg:
 		return m, Quit
 	}
+
 	return m, nil
 }
 
@@ -84,3 +96,35 @@ func TestTeaKill(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func TestTeaBatchMsg(t *testing.T) {
+	var buf bytes.Buffer
+	var in bytes.Buffer
+
+	inc := func() Msg {
+		return incrementMsg{}
+	}
+
+	m := &testModel{}
+	p := NewProgram(m, WithInput(&in), WithOutput(&buf))
+	go func() {
+		p.Send(batchMsg{inc, inc})
+
+		for {
+			time.Sleep(time.Millisecond)
+			i := m.counter.Load()
+			if i != nil && i.(int) >= 2 {
+				p.Quit()
+				return
+			}
+		}
+	}()
+
+	if _, err := p.Run(); err != nil {
+		t.Fatal(err)
+	}
+
+	if m.counter.Load() != 2 {
+		t.Fatalf("counter should be 2, got %d", m.counter)
+	}
+}