Send resize event to leaf node models

pkg/panes/alignment_test.go

@@ -118,7 +118,7 @@ func TestWithAlignment(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			p := panes.NewLeaf(newDummyModel("foo", nil, nil)).WithDimensions(14, 5)
+			p, _ := panes.NewLeaf(newDummyModel("foo", nil, nil)).WithDimensions(14, 5)
 
 			p = p.WithAlignment(tc.vertical, tc.horizontal)
 

pkg/panes/dummymodel_test.go

@@ -19,13 +19,17 @@ func newDummyModel(text string, initCmd func() tea.Msg, updateCallback func(tea.
 }
 
 func (m dummyModel) Init() tea.Cmd {
-	m.initCmd()
+	if m.initCmd != nil {
+		m.initCmd()
+	}
 
 	return m.initCmd
 }
 
 func (m dummyModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
-	m.updateCallback(msg)
+	if m.updateCallback != nil {
+		m.updateCallback(msg)
+	}
 
 	return m, nil
 }

pkg/panes/layout.go

@@ -1,12 +1,17 @@
 package panes
 
-func (m Pane) WithDimensions(width, height int) Pane {
+import tea "github.com/charmbracelet/bubbletea"
+
+type ViewableSize struct {
+	Width  int
+	Height int
+}
+
+func (m Pane) WithDimensions(width, height int) (Pane, tea.Cmd) {
 	m.width = width
 	m.height = height
 
-	m = m.recalculateDimensions()
-
-	return m
+	return m.recalculateDimensions()
 }
 
 func (m Pane) WithDirection(direction Direction) Pane {
@@ -29,10 +34,17 @@ func (m Pane) Children() []Pane {
 	return m.children
 }
 
-func (m Pane) recalculateDimensions() Pane {
+func (m Pane) recalculateDimensions() (Pane, tea.Cmd) {
 	numChildren := len(m.children)
 	if numChildren == 0 {
-		return m
+		var cmd tea.Cmd = nil
+		if m.model != nil {
+			m.model, cmd = m.model.Update(ViewableSize{
+				Width:  m.width - 2,
+				Height: m.height - 2,
+			})
+		}
+		return m, cmd
 	}
 	width := m.width
 	height := m.height
@@ -43,9 +55,15 @@ func (m Pane) recalculateDimensions() Pane {
 		width = width / numChildren
 	}
 
+	var (
+		cmd  tea.Cmd
+		cmds []tea.Cmd
+	)
+
 	for i := range m.children {
-		m.children[i] = m.children[i].WithDimensions(width, height)
+		m.children[i], cmd = m.children[i].WithDimensions(width, height)
+		cmds = append(cmds, cmd)
 	}
 
-	return m
+	return m, tea.Batch(cmds...)
 }

pkg/panes/layout_test.go

@@ -9,14 +9,14 @@ import (
 
 func TestFullPaneTakesFullDimensions(t *testing.T) {
 	// Ensure a single pane with no children takes the entire dimensions
-	pane := panes.NewLeaf(nil).WithDimensions(200, 100)
+	pane, _ := panes.NewLeaf(nil).WithDimensions(200, 100)
 	assert.Equal(t, 200, pane.Width(), "Wrong width")
 	assert.Equal(t, 100, pane.Height(), "Wrong height")
 }
 
 func TestHorizontalPanesSplitHorizontally(t *testing.T) {
 	// Ensure a single pane with ten children horizontally splits the width
-	pane := panes.NewNode(panes.DirectionHorizontal, panes.NewLeaf(nil), panes.NewLeaf(nil)).WithDimensions(100, 100)
+	pane, _ := panes.NewNode(panes.DirectionHorizontal, panes.NewLeaf(nil), panes.NewLeaf(nil)).WithDimensions(100, 100)
 	for i, child := range pane.Children() {
 		assert.Equal(t, 50, child.Width(), "Wrong width for child %d", i)
 		assert.Equal(t, 100, child.Height(), "Wrong height for child %d", i)
@@ -25,7 +25,7 @@ func TestHorizontalPanesSplitHorizontally(t *testing.T) {
 
 func TestVerticalPanesSplitVertically(t *testing.T) {
 	// Ensure a single pane with ten children vertically splits the height
-	pane := panes.NewNode(panes.DirectionVertical, panes.NewLeaf(nil), panes.NewLeaf(nil)).WithDimensions(100, 100)
+	pane, _ := panes.NewNode(panes.DirectionVertical, panes.NewLeaf(nil), panes.NewLeaf(nil)).WithDimensions(100, 100)
 	for i, child := range pane.Children() {
 		assert.Equal(t, 100, child.Width(), "Wrong width for child %d", i)
 		assert.Equal(t, 50, child.Height(), "Wrong height for child %d", i)
@@ -42,7 +42,7 @@ func TestNestedPanesSplitWithinParent(t *testing.T) {
 		sideChildren[i] = panes.NewLeaf(nil)
 	}
 
-	pane := panes.NewNode(panes.DirectionHorizontal,
+	pane, _ := panes.NewNode(panes.DirectionHorizontal,
 		panes.NewLeaf(nil),
 		panes.NewNode(panes.DirectionVertical, sideChildren...),
 	).WithDimensions(100, 100)
@@ -66,7 +66,7 @@ func TestNestedPanesSplitWithinParent(t *testing.T) {
 func TestChangingDirectionChangesLayout(t *testing.T) {
 	// With a parent pane that contains two leaf children split horizontally,
 	// switch to vertical and make sure the layout changes.
-	pane := panes.NewNode(panes.DirectionHorizontal, panes.NewLeaf(nil), panes.NewLeaf(nil)).WithDimensions(100, 100)
+	pane, _ := panes.NewNode(panes.DirectionHorizontal, panes.NewLeaf(nil), panes.NewLeaf(nil)).WithDimensions(100, 100)
 
 	for _, child := range pane.Children() {
 		assert.Equal(t, 50, child.Width(), "Wrong width for child")

pkg/panes/panes_test.go

@@ -59,11 +59,34 @@ func TestUpdateParentNodeSendsUpdateToChildren(t *testing.T) {
 	assert.True(t, sawUpdate, "Model should have seen update")
 }
 
+func TestUpdateSendsResizeEventToLeafNodes(t *testing.T) {
+	// Given a parent node with nested children,
+	// the model should receive the update message
+	var resizeMsg panes.ViewableSize
+	dummy := newDummyModel("testing", nil, func(msg tea.Msg) {
+		switch msg := msg.(type) {
+		case panes.ViewableSize:
+			resizeMsg = msg
+		}
+	})
+	parent := panes.NewNode(panes.DirectionHorizontal, panes.NewLeaf(dummy))
+
+	const (
+		newWidth  = 48
+		newHeight = 24
+	)
+
+	parent.WithDimensions(newWidth, newHeight)
+
+	assert.Equal(t, newWidth-2, resizeMsg.Width, "Model should have seen new width")
+	assert.Equal(t, newHeight-2, resizeMsg.Height, "Model should have seen new height")
+}
+
 func TestViewLeafNodeShowsInnerModel(t *testing.T) {
 	// Given a leaf node with a simple model,
 	// the view should return the inner model's view
 	dummy := newDummyModel("testing", nil, nil)
-	pane := panes.NewLeaf(dummy).WithDimensions(100, 100)
+	pane, _ := panes.NewLeaf(dummy).WithDimensions(100, 100)
 
 	assert.Contains(t, pane.View(), "testing", "View should return inner model's view")
 }
@@ -73,7 +96,7 @@ func TestViewLeafNodeCropsInnerModel(t *testing.T) {
 	// the view should crop the text to the pane's dimensions.
 	const expectedLines = 2
 	text := strings.Repeat("testing\n", 100)
-	pane := panes.NewLeaf(newDummyModel(text, nil, nil)).
+	pane, _ := panes.NewLeaf(newDummyModel(text, nil, nil)).
 		WithDimensions(10, expectedLines+2) // Account for border
 
 	numTesting := strings.Count(pane.View(), "testing")
@@ -86,7 +109,7 @@ func TestViewParentNodeShowsInnerModelsOfChildren(t *testing.T) {
 	// the view should return the inner model's view
 	dummyLeft := newDummyModel("left", nil, nil)
 	dummyRight := newDummyModel("right", nil, nil)
-	pane := panes.NewNode(
+	pane, _ := panes.NewNode(
 		panes.DirectionHorizontal,
 		panes.NewLeaf(dummyLeft),
 		panes.NewLeaf(dummyRight),
@@ -99,7 +122,7 @@ func TestViewParentNodeShowsInnerModelsOfChildren(t *testing.T) {
 func TestViewHorizontalGoesLeftToRight(t *testing.T) {
 	dummyLeft := newDummyModel("left", nil, nil)
 	dummyRight := newDummyModel("right", nil, nil)
-	pane := panes.NewNode(
+	pane, _ := panes.NewNode(
 		panes.DirectionHorizontal,
 		panes.NewLeaf(dummyLeft),
 		panes.NewLeaf(dummyRight),
@@ -114,7 +137,7 @@ func TestViewHorizontalGoesLeftToRight(t *testing.T) {
 func TestViewVerticalGoesTopToBottom(t *testing.T) {
 	dummyTop := newDummyModel("top", nil, nil)
 	dummyBottom := newDummyModel("bottom", nil, nil)
-	pane := panes.NewNode(panes.DirectionVertical, panes.NewLeaf(dummyTop), panes.NewLeaf(dummyBottom)).WithDimensions(10, 100)
+	pane, _ := panes.NewNode(panes.DirectionVertical, panes.NewLeaf(dummyTop), panes.NewLeaf(dummyBottom)).WithDimensions(10, 100)
 
 	indexTop := strings.Index(pane.View(), "top")
 	indexBottom := strings.Index(pane.View(), "bottom")
@@ -127,7 +150,7 @@ func TestViewTitleIsShown(t *testing.T) {
 │testing │
 ╰────────╯`
 	dummy := newDummyModel("testing", nil, nil)
-	pane := panes.NewLeaf(dummy).WithName("title").WithDimensions(10, 3)
+	pane, _ := panes.NewLeaf(dummy).WithName("title").WithDimensions(10, 3)
 
 	assert.Equal(t, expectedView, pane.View())
 }
@@ -137,7 +160,7 @@ func TestViewNoTitleShowsBorderProperly(t *testing.T) {
 │testing │
 ╰────────╯`
 	dummy := newDummyModel("testing", nil, nil)
-	pane := panes.NewLeaf(dummy).WithDimensions(10, 3)
+	pane, _ := panes.NewLeaf(dummy).WithDimensions(10, 3)
 
 	assert.Equal(t, expectedView, pane.View())
 }
@@ -147,7 +170,7 @@ func TestViewRemovingTitleShowsBorderProperly(t *testing.T) {
 │testing │
 ╰────────╯`
 	dummy := newDummyModel("testing", nil, nil)
-	pane := panes.NewLeaf(dummy).WithName("title").WithDimensions(10, 3)
+	pane, _ := panes.NewLeaf(dummy).WithName("title").WithDimensions(10, 3)
 
 	pane = pane.WithName("")
 

pkg/yakdash/yakdash.go

@@ -38,7 +38,8 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		}
 
 	case tea.WindowSizeMsg:
-		m.rootPane = m.rootPane.WithDimensions(msg.Width, msg.Height)
+		m.rootPane, cmd = m.rootPane.WithDimensions(msg.Width, msg.Height)
+		cmds = append(cmds, cmd)
 	}
 
 	m.rootPane, cmd = m.rootPane.Update(msg)