fix(usecase): reject invalid pane split directions

commit: e88f43d825c9c3fae01755e6a2147ed006302fc8
author: brice · 4mo ago · 2026-06-20 09:49 UTC
committer: brice · 4mo ago · 2026-06-20 10:00 UTC
parent: 2be8535
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

2 files · +99 -0

M internal/application/usecase/manage_panes.go +8 -0


@@ -112,6 +112,14 @@ func (uc *ManagePanesUseCase) Split(ctx context.Context, input SplitPaneInput) (
112	112		return nil, fmt.Errorf("target pane is required")
113	113		}
114	114
	115	+	// Validate split direction before any mutations
	116	+	switch input.Direction {
	117	+	case SplitLeft, SplitRight, SplitUp, SplitDown:
	118	+	// valid
	119	+	default:
	120	+	return nil, fmt.Errorf("invalid split direction: %s", input.Direction)
	121	+	}
	122	+
115	123		// If target is inside a stack, split around the entire stack
116	124		// (i.e., create the new pane as a sibling to the stack, not inside it)
117	125		// This applies to all directions - we don't want to nest split containers inside stacks.


@@ -112,6 +112,14 @@ func (uc *ManagePanesUseCase) Split(ctx context.Context, input SplitPaneInput) (
112	return nil, fmt.Errorf("target pane is required")	112		return nil, fmt.Errorf("target pane is required")
113	}	113		}
114		114
		115	+	// Validate split direction before any mutations
		116	+	switch input.Direction {
		117	+	case SplitLeft, SplitRight, SplitUp, SplitDown:
		118	+	// valid
		119	+	default:
		120	+	return nil, fmt.Errorf("invalid split direction: %s", input.Direction)
		121	+	}
		122	+
115	// If target is inside a stack, split around the entire stack	123		// If target is inside a stack, split around the entire stack
116	// (i.e., create the new pane as a sibling to the stack, not inside it)	124		// (i.e., create the new pane as a sibling to the stack, not inside it)
117	// This applies to all directions - we don't want to nest split containers inside stacks.	125		// This applies to all directions - we don't want to nest split containers inside stacks.

A internal/application/usecase/manage_panes_split_test.go +91 -0

@@ -0,0 +1,91 @@
	1	+	package usecase
	2	+
	3	+	import (
	4	+	"context"
	5	+	"strings"
	6	+	"testing"
	7	+
	8	+	"github.com/bnema/dumber/internal/domain/entity"
	9	+	)
	10	+
	11	+	func TestManagePanesUseCase_Split_ValidDirections(t *testing.T) {
	12	+	uc := NewManagePanesUseCase(func() string { return "id" })
	13	+	ctx := context.Background()
	14	+
	15	+	dirs := []SplitDirection{SplitLeft, SplitRight, SplitUp, SplitDown}
	16	+	for _, dir := range dirs {
	17	+	t.Run(string(dir), func(t *testing.T) {
	18	+	target := leaf("target")
	19	+	ws := &entity.Workspace{Root: target, ActivePaneID: "target"}
	20	+	target.Parent = nil // root
	21	+
	22	+	out, err := uc.Split(ctx, SplitPaneInput{
	23	+	Workspace: ws,
	24	+	TargetPane: target,
	25	+	Direction: dir,
	26	+	})
	27	+	if err != nil {
	28	+	t.Fatalf("unexpected error for direction %s: %v", dir, err)
	29	+	}
	30	+	if out == nil {
	31	+	t.Fatalf("output is nil for direction %s", dir)
	32	+	}
	33	+	if out.NewPaneNode == nil {
	34	+	t.Fatalf("new pane node is nil for direction %s", dir)
	35	+	}
	36	+	if out.ParentNode == nil {
	37	+	t.Fatalf("parent node is nil for direction %s", dir)
	38	+	}
	39	+	if !out.ParentNode.IsSplit() {
	40	+	t.Fatalf("parent node should be a split for direction %s, got SplitDir=%v", dir, out.ParentNode.SplitDir)
	41	+	}
	42	+	if ws.Root != out.ParentNode {
	43	+	t.Fatalf("workspace root should be the parent node for direction %s", dir)
	44	+	}
	45	+	// Verify the tree has 2 leaf panes
	46	+	if ws.PaneCount() != 2 {
	47	+	t.Fatalf("workspace should have 2 panes for direction %s, got %d", dir, ws.PaneCount())
	48	+	}
	49	+	})
	50	+	}
	51	+	}
	52	+
	53	+	func TestManagePanesUseCase_Split_InvalidDirection_ReturnsError(t *testing.T) {
	54	+	uc := NewManagePanesUseCase(func() string { return "id" })
	55	+	ctx := context.Background()
	56	+
	57	+	target := leaf("target")
	58	+	ws := &entity.Workspace{Root: target, ActivePaneID: "target"}
	59	+
	60	+	// Save initial state
	61	+	initialRoot := ws.Root
	62	+	initialActive := ws.ActivePaneID
	63	+
	64	+	_, err := uc.Split(ctx, SplitPaneInput{
	65	+	Workspace: ws,
	66	+	TargetPane: target,
	67	+	Direction: SplitDirection("diagonal"),
	68	+	})
	69	+	if err == nil {
	70	+	t.Fatalf("expected error for invalid direction, got nil")
	71	+	}
	72	+	if !strings.Contains(err.Error(), "invalid split direction: diagonal") {
	73	+	t.Fatalf("unexpected error message: %v", err)
	74	+	}
	75	+
	76	+	// Verify workspace state is unchanged
	77	+	if ws.Root != initialRoot {
	78	+	t.Fatalf("workspace root was modified")
	79	+	}
	80	+	if ws.ActivePaneID != initialActive {
	81	+	t.Fatalf("workspace active pane was modified")
	82	+	}
	83	+	// Verify target pane parent is still nil (was root)
	84	+	if target.Parent != nil {
	85	+	t.Fatalf("target pane parent was modified")
	86	+	}
	87	+	// Verify pane count is still 1
	88	+	if ws.PaneCount() != 1 {
	89	+	t.Fatalf("workspace pane count changed: got %d, want 1", ws.PaneCount())
	90	+	}
	91	+	}

@@ -0,0 +1,91 @@
	1	+	package usecase
	2	+
	3	+	import (
	4	+	"context"
	5	+	"strings"
	6	+	"testing"
	7	+
	8	+	"github.com/bnema/dumber/internal/domain/entity"
	9	+	)
	10	+
	11	+	func TestManagePanesUseCase_Split_ValidDirections(t *testing.T) {
	12	+	uc := NewManagePanesUseCase(func() string { return "id" })
	13	+	ctx := context.Background()
	14	+
	15	+	dirs := []SplitDirection{SplitLeft, SplitRight, SplitUp, SplitDown}
	16	+	for _, dir := range dirs {
	17	+	t.Run(string(dir), func(t *testing.T) {
	18	+	target := leaf("target")
	19	+	ws := &entity.Workspace{Root: target, ActivePaneID: "target"}
	20	+	target.Parent = nil // root
	21	+
	22	+	out, err := uc.Split(ctx, SplitPaneInput{
	23	+	Workspace: ws,
	24	+	TargetPane: target,
	25	+	Direction: dir,
	26	+	})
	27	+	if err != nil {
	28	+	t.Fatalf("unexpected error for direction %s: %v", dir, err)
	29	+	}
	30	+	if out == nil {
	31	+	t.Fatalf("output is nil for direction %s", dir)
	32	+	}
	33	+	if out.NewPaneNode == nil {
	34	+	t.Fatalf("new pane node is nil for direction %s", dir)
	35	+	}
	36	+	if out.ParentNode == nil {
	37	+	t.Fatalf("parent node is nil for direction %s", dir)
	38	+	}
	39	+	if !out.ParentNode.IsSplit() {
	40	+	t.Fatalf("parent node should be a split for direction %s, got SplitDir=%v", dir, out.ParentNode.SplitDir)
	41	+	}
	42	+	if ws.Root != out.ParentNode {
	43	+	t.Fatalf("workspace root should be the parent node for direction %s", dir)
	44	+	}
	45	+	// Verify the tree has 2 leaf panes
	46	+	if ws.PaneCount() != 2 {
	47	+	t.Fatalf("workspace should have 2 panes for direction %s, got %d", dir, ws.PaneCount())
	48	+	}
	49	+	})
	50	+	}
	51	+	}
	52	+
	53	+	func TestManagePanesUseCase_Split_InvalidDirection_ReturnsError(t *testing.T) {
	54	+	uc := NewManagePanesUseCase(func() string { return "id" })
	55	+	ctx := context.Background()
	56	+
	57	+	target := leaf("target")
	58	+	ws := &entity.Workspace{Root: target, ActivePaneID: "target"}
	59	+
	60	+	// Save initial state
	61	+	initialRoot := ws.Root
	62	+	initialActive := ws.ActivePaneID
	63	+
	64	+	_, err := uc.Split(ctx, SplitPaneInput{
	65	+	Workspace: ws,
	66	+	TargetPane: target,
	67	+	Direction: SplitDirection("diagonal"),
	68	+	})
	69	+	if err == nil {
	70	+	t.Fatalf("expected error for invalid direction, got nil")
	71	+	}
	72	+	if !strings.Contains(err.Error(), "invalid split direction: diagonal") {
	73	+	t.Fatalf("unexpected error message: %v", err)
	74	+	}
	75	+
	76	+	// Verify workspace state is unchanged
	77	+	if ws.Root != initialRoot {
	78	+	t.Fatalf("workspace root was modified")
	79	+	}
	80	+	if ws.ActivePaneID != initialActive {
	81	+	t.Fatalf("workspace active pane was modified")
	82	+	}
	83	+	// Verify target pane parent is still nil (was root)
	84	+	if target.Parent != nil {
	85	+	t.Fatalf("target pane parent was modified")
	86	+	}
	87	+	// Verify pane count is still 1
	88	+	if ws.PaneCount() != 1 {
	89	+	t.Fatalf("workspace pane count changed: got %d, want 1", ws.PaneCount())
	90	+	}
	91	+	}