fix: handle nested SequenceMsg in event loop and use sync.WaitGroup f…

examples/go.mod

@@ -23,7 +23,7 @@ require (
 	github.com/aymanbagabas/go-udiff v0.2.0 // indirect
 	github.com/aymerick/douceur v0.2.0 // indirect
 	github.com/charmbracelet/colorprofile v0.2.3-0.20250311203215-f60798e515dc // indirect
-	github.com/charmbracelet/x/ansi v0.9.2 // indirect
+	github.com/charmbracelet/x/ansi v0.9.3 // indirect
 	github.com/charmbracelet/x/cellbuf v0.0.13 // indirect
 	github.com/charmbracelet/x/exp/golden v0.0.0-20241011142426-46044092ad91 // indirect
 	github.com/charmbracelet/x/exp/slice v0.0.0-20250327172914-2fdc97757edf // indirect
@@ -45,8 +45,7 @@ require (
 	github.com/yuin/goldmark v1.7.8 // indirect
 	github.com/yuin/goldmark-emoji v1.0.5 // indirect
 	golang.org/x/net v0.38.0 // indirect
-	golang.org/x/sync v0.14.0 // indirect
-	golang.org/x/sys v0.33.0 // indirect
+	golang.org/x/sys v0.34.0 // indirect
 	golang.org/x/term v0.31.0 // indirect
 	golang.org/x/text v0.24.0 // indirect
 )

examples/go.sum

@@ -24,8 +24,8 @@ github.com/charmbracelet/harmonica v0.2.0 h1:8NxJWRWg/bzKqqEaaeFNipOu77YR5t8aSwG
 github.com/charmbracelet/harmonica v0.2.0/go.mod h1:KSri/1RMQOZLbw7AHqgcBycp8pgJnQMYYT8QZRqZ1Ao=
 github.com/charmbracelet/lipgloss v1.1.1-0.20250404203927-76690c660834 h1:ZR7e0ro+SZZiIZD7msJyA+NjkCNNavuiPBLgerbOziE=
 github.com/charmbracelet/lipgloss v1.1.1-0.20250404203927-76690c660834/go.mod h1:aKC/t2arECF6rNOnaKaVU6y4t4ZeHQzqfxedE/VkVhA=
-github.com/charmbracelet/x/ansi v0.9.2 h1:92AGsQmNTRMzuzHEYfCdjQeUzTrgE1vfO5/7fEVoXdY=
-github.com/charmbracelet/x/ansi v0.9.2/go.mod h1:3RQDQ6lDnROptfpWuUVIUG64bD2g2BgntdxH0Ya5TeE=
+github.com/charmbracelet/x/ansi v0.9.3 h1:BXt5DHS/MKF+LjuK4huWrC6NCvHtexww7dMayh6GXd0=
+github.com/charmbracelet/x/ansi v0.9.3/go.mod h1:3RQDQ6lDnROptfpWuUVIUG64bD2g2BgntdxH0Ya5TeE=
 github.com/charmbracelet/x/cellbuf v0.0.13 h1:/KBBKHuVRbq1lYx5BzEHBAFBP8VcQzJejZ/IA3iR28k=
 github.com/charmbracelet/x/cellbuf v0.0.13/go.mod h1:xe0nKWGd3eJgtqZRaN9RjMtK7xUYchjzPr7q6kcvCCs=
 github.com/charmbracelet/x/exp/golden v0.0.0-20241011142426-46044092ad91 h1:payRxjMjKgx2PaCWLZ4p3ro9y97+TVLZNaRZgJwSVDQ=
@@ -86,12 +86,10 @@ golang.org/x/exp v0.0.0-20220909182711-5c715a9e8561 h1:MDc5xs78ZrZr3HMQugiXOAkSZ
 golang.org/x/exp v0.0.0-20220909182711-5c715a9e8561/go.mod h1:cyybsKvd6eL0RnXn6p/Grxp8F5bW7iYuBgsNCOHpMYE=
 golang.org/x/net v0.38.0 h1:vRMAPTMaeGqVhG5QyLJHqNDwecKTomGeqbnfZyKlBI8=
 golang.org/x/net v0.38.0/go.mod h1:ivrbrMbzFq5J41QOQh0siUuly180yBYtLp+CKbEaFx8=
-golang.org/x/sync v0.14.0 h1:woo0S4Yywslg6hp4eUFjTVOyKt0RookbpAHG4c1HmhQ=
-golang.org/x/sync v0.14.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=
 golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.33.0 h1:q3i8TbbEz+JRD9ywIRlyRAQbM0qF7hu24q3teo2hbuw=
-golang.org/x/sys v0.33.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
+golang.org/x/sys v0.34.0 h1:H5Y5sJ2L2JRdyv7ROF1he/lPdvFsd0mJHFw2ThKHxLA=
+golang.org/x/sys v0.34.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
 golang.org/x/term v0.31.0 h1:erwDkOK1Msy6offm1mOgvspSkslFnIGsFnxOKoufg3o=
 golang.org/x/term v0.31.0/go.mod h1:R4BeIy7D95HzImkxGkTW1UQTtP54tio2RyHz7PwK0aw=
 golang.org/x/text v0.24.0 h1:dd5Bzh4yt5KYA8f9CJHCP4FB4D51c2c6JvN37xJJkJ0=

tea.go

@@ -24,7 +24,6 @@ import (
 
 	"github.com/charmbracelet/x/term"
 	"github.com/muesli/cancelreader"
-	"golang.org/x/sync/errgroup"
 )
 
 // ErrProgramPanic is returned by [Program.Run] when the program recovers from a panic.
@@ -473,11 +472,10 @@ func (p *Program) eventLoop(model Model, cmds chan Cmd) (Model, error) {
 
 			case BatchMsg:
 				for _, cmd := range msg {
-					select {
-					case <-p.ctx.Done():
-						return model, nil
-					case cmds <- cmd:
+					if cmd == nil {
+						continue
 					}
+					go p.Send(cmd())
 				}
 				continue
 
@@ -490,22 +488,31 @@ func (p *Program) eventLoop(model Model, cmds chan Cmd) (Model, error) {
 						}
 
 						msg := cmd()
-						if batchMsg, ok := msg.(BatchMsg); ok {
-							g, _ := errgroup.WithContext(p.ctx)
-							for _, cmd := range batchMsg {
+						switch msg := msg.(type) {
+						case BatchMsg:
+							var wg sync.WaitGroup
+							for _, cmd := range msg {
+								if cmd == nil {
+									continue
+								}
+								wg.Add(1)
 								cmd := cmd
-								g.Go(func() error {
+								go func() {
+									defer wg.Done()
 									p.Send(cmd())
-									return nil
-								})
+								}()
 							}
-
-							//nolint:errcheck,gosec
-							g.Wait() // wait for all commands from batch msg to finish
-							continue
+							wg.Wait()
+						case sequenceMsg:
+							for _, cmd := range msg {
+								if cmd == nil {
+									continue
+								}
+								p.Send(cmd())
+							}
+						default:
+							p.Send(msg)
 						}
-
-						p.Send(msg)
 					}
 				}()
 

tea_test.go

@@ -424,6 +424,27 @@ func TestTeaSequenceMsgWithBatchMsg(t *testing.T) {
 	}
 }
 
+func TestTeaNestedSequenceMsg(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 p.Send(sequenceMsg{inc, Sequence(inc, inc), Quit})
+
+	if _, err := p.Run(); err != nil {
+		t.Fatal(err)
+	}
+
+	if m.counter.Load() != 3 {
+		t.Fatalf("counter should be 3, got %d", m.counter.Load())
+	}
+}
+
 func TestTeaSend(t *testing.T) {
 	var buf bytes.Buffer
 	var in bytes.Buffer