chore: bump go from 1.13 to 1.18

This reverts the code back to the logic from 4ce16e8 which fixed the
issue of the cursor not being moved when an initial value was set with
SetValue.

The fix regressed in 16053f4.

README.md

@@ -41,6 +41,18 @@ the common, and many customization options.
 * [Example code, one field](https://github.com/charmbracelet/tea/tree/master/examples/textinput/main.go)
 * [Example code, many fields](https://github.com/charmbracelet/tea/tree/master/examples/textinputs/main.go)
 
+## Text Area
+
+<img src="https://stuff.charm.sh/bubbles-examples/textarea.gif" width="400" alt="Text Area Example">
+
+A text area field, akin to an `<textarea />` in HTML. Allows for input that
+spans multiple lines. Supports unicode, pasting, vertical scrolling when the
+value exceeds the width and height of the element,  and many customization
+options.
+
+* [Example code, chat input](https://github.com/charmbracelet/tea/tree/master/examples/chat/main.go)
+* [Example code, story time input](https://github.com/charmbracelet/tea/tree/master/examples/textarea/main.go)
+
 
 ## Progress
 

cursor/cursor.go

@@ -0,0 +1,207 @@
+package cursor
+
+import (
+	"context"
+	"time"
+
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+)
+
+const defaultBlinkSpeed = time.Millisecond * 530
+
+// initialBlinkMsg initializes cursor blinking.
+type initialBlinkMsg struct{}
+
+// BlinkMsg signals that the cursor should blink. It contains metadata that
+// allows us to tell if the blink message is the one we're expecting.
+type BlinkMsg struct {
+	id  int
+	tag int
+}
+
+// blinkCanceled is sent when a blink operation is canceled.
+type blinkCanceled struct{}
+
+// blinkCtx manages cursor blinking.
+type blinkCtx struct {
+	ctx    context.Context
+	cancel context.CancelFunc
+}
+
+// Mode describes the behavior of the cursor.
+type Mode int
+
+// Available cursor modes.
+const (
+	CursorBlink Mode = iota
+	CursorStatic
+	CursorHide
+)
+
+// String returns the cursor mode in a human-readable format. This method is
+// provisional and for informational purposes only.
+func (c Mode) String() string {
+	return [...]string{
+		"blink",
+		"static",
+		"hidden",
+	}[c]
+}
+
+// Model is the Bubble Tea model for this cursor element.
+type Model struct {
+	BlinkSpeed time.Duration
+	// Style for styling the cursor block.
+	Style lipgloss.Style
+	// TextStyle is the style used for the cursor when it is hidden (when blinking).
+	// I.e. displaying normal text.
+	TextStyle lipgloss.Style
+
+	// char is the character under the cursor
+	char string
+	// The ID of this Model as it relates to other cursors
+	id int
+	// focus indicates whether the containing input is focused
+	focus bool
+	// Cursor Blink state.
+	Blink bool
+	// Used to manage cursor blink
+	blinkCtx *blinkCtx
+	// The ID of the blink message we're expecting to receive.
+	blinkTag int
+	// cursorMode determines the behavior of the cursor
+	cursorMode Mode
+}
+
+// New creates a new model with default settings.
+func New() Model {
+	return Model{
+		BlinkSpeed: defaultBlinkSpeed,
+
+		Blink:      true,
+		cursorMode: CursorBlink,
+
+		blinkCtx: &blinkCtx{
+			ctx: context.Background(),
+		},
+	}
+}
+
+// Update updates the cursor.
+func (m Model) Update(msg tea.Msg) (Model, tea.Cmd) {
+	switch msg := msg.(type) {
+	case initialBlinkMsg:
+		// We accept all initialBlinkMsgs generated by the Blink command.
+
+		if m.cursorMode != CursorBlink || !m.focus {
+			return m, nil
+		}
+
+		cmd := m.BlinkCmd()
+		return m, cmd
+
+	case BlinkMsg:
+		// We're choosy about whether to accept blinkMsgs so that our cursor
+		// only exactly when it should.
+
+		// Is this model blink-able?
+		if m.cursorMode != CursorBlink || !m.focus {
+			return m, nil
+		}
+
+		// Were we expecting this blink message?
+		if msg.id != m.id || msg.tag != m.blinkTag {
+			return m, nil
+		}
+
+		var cmd tea.Cmd
+		if m.cursorMode == CursorBlink {
+			m.Blink = !m.Blink
+			cmd = m.BlinkCmd()
+		}
+		return m, cmd
+
+	case blinkCanceled: // no-op
+		return m, nil
+	}
+	return m, nil
+}
+
+// CursorMode returns the model's cursor mode. For available cursor modes, see
+// type CursorMode.
+func (m Model) CursorMode() Mode {
+	return m.cursorMode
+}
+
+// SetCursorMode sets the model's cursor mode. This method returns a command.
+//
+// For available cursor modes, see type CursorMode.
+func (m *Model) SetCursorMode(mode Mode) tea.Cmd {
+	m.cursorMode = mode
+	m.Blink = m.cursorMode == CursorHide || !m.focus
+	if mode == CursorBlink {
+		return Blink
+	}
+	return nil
+}
+
+// BlinkCmd is an command used to manage cursor blinking.
+func (m *Model) BlinkCmd() tea.Cmd {
+	if m.cursorMode != CursorBlink {
+		return nil
+	}
+
+	if m.blinkCtx != nil && m.blinkCtx.cancel != nil {
+		m.blinkCtx.cancel()
+	}
+
+	ctx, cancel := context.WithTimeout(m.blinkCtx.ctx, m.BlinkSpeed)
+	m.blinkCtx.cancel = cancel
+
+	m.blinkTag++
+
+	return func() tea.Msg {
+		defer cancel()
+		<-ctx.Done()
+		if ctx.Err() == context.DeadlineExceeded {
+			return BlinkMsg{id: m.id, tag: m.blinkTag}
+		}
+		return blinkCanceled{}
+	}
+}
+
+// Blink is a command used to initialize cursor blinking.
+func Blink() tea.Msg {
+	return initialBlinkMsg{}
+}
+
+// Focus focuses the cursor to allow it to blink if desired.
+func (m *Model) Focus() tea.Cmd {
+	m.focus = true
+	m.Blink = m.cursorMode == CursorHide // show the cursor unless we've explicitly hidden it
+
+	if m.cursorMode == CursorBlink && m.focus {
+		return m.BlinkCmd()
+	}
+	return nil
+}
+
+// Blur blurs the cursor.
+func (m *Model) Blur() {
+	m.focus = false
+	m.Blink = true
+}
+
+// SetChar sets the character under the cursor.
+func (m *Model) SetChar(char string) {
+	m.char = char
+}
+
+// View displays the cursor.
+func (m Model) View() string {
+	if m.Blink {
+		return m.TextStyle.Render(m.char)
+	}
+	return m.Style.Inline(true).Reverse(true).Render(m.char)
+}

go.mod

@@ -1,16 +1,26 @@
 module github.com/charmbracelet/bubbles
 
-go 1.13
+go 1.18
 
 require (
 	github.com/atotto/clipboard v0.1.4
-	github.com/charmbracelet/bubbletea v0.21.0
+	github.com/charmbracelet/bubbletea v0.22.0
 	github.com/charmbracelet/harmonica v0.2.0
 	github.com/charmbracelet/lipgloss v0.5.0
-	github.com/kylelemons/godebug v1.1.0 // indirect
 	github.com/lucasb-eyer/go-colorful v1.2.0
 	github.com/mattn/go-runewidth v0.0.13
 	github.com/muesli/reflow v0.3.0
-	github.com/muesli/termenv v0.11.1-0.20220212125758-44cd13922739
+	github.com/muesli/termenv v0.12.0
 	github.com/sahilm/fuzzy v0.1.0
 )
+
+require (
+	github.com/containerd/console v1.0.3 // indirect
+	github.com/kylelemons/godebug v1.1.0 // indirect
+	github.com/mattn/go-isatty v0.0.14 // indirect
+	github.com/muesli/ansi v0.0.0-20211018074035-2e021307bc4b // indirect
+	github.com/muesli/cancelreader v0.2.1 // indirect
+	github.com/rivo/uniseg v0.2.0 // indirect
+	golang.org/x/sys v0.0.0-20220209214540-3681064d5158 // indirect
+	golang.org/x/term v0.0.0-20210927222741-03fcf44c2211 // indirect
+)

go.sum

@@ -1,7 +1,7 @@
 github.com/atotto/clipboard v0.1.4 h1:EH0zSVneZPSuFR11BlR9YppQTVDbh5+16AmcJi4g1z4=
 github.com/atotto/clipboard v0.1.4/go.mod h1:ZY9tmq7sm5xIbd9bOK4onWV4S6X0u6GY7Vn0Yu86PYI=
-github.com/charmbracelet/bubbletea v0.21.0 h1:f3y+kanzgev5PA916qxmDybSHU3N804uOnKnhRPXTcI=
+github.com/charmbracelet/bubbletea v0.22.0 h1:E1BTNSE3iIrq0G0X6TjGAmrQ32cGCbFDPcIuImikrUc=
-github.com/charmbracelet/bubbletea v0.21.0/go.mod h1:GgmJMec61d08zXsOhqRC/AiOx4K4pmz+VIcRIm1FKr4=
+github.com/charmbracelet/bubbletea v0.22.0/go.mod h1:aoVIwlNlr5wbCB26KhxfrqAn0bMp4YpJcoOelbxApjs=
 github.com/charmbracelet/harmonica v0.2.0 h1:8NxJWRWg/bzKqqEaaeFNipOu77YR5t8aSwG4pgaUBiQ=
 github.com/charmbracelet/harmonica v0.2.0/go.mod h1:KSri/1RMQOZLbw7AHqgcBycp8pgJnQMYYT8QZRqZ1Ao=
 github.com/charmbracelet/lipgloss v0.5.0 h1:lulQHuVeodSgDez+3rGiuxlPVXSnhth442DATR2/8t8=
@@ -20,19 +20,17 @@ github.com/mattn/go-runewidth v0.0.13 h1:lTGmDsbAYt5DmK6OnoV7EuIF1wEIFAcxld6ypU4
 github.com/mattn/go-runewidth v0.0.13/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
 github.com/muesli/ansi v0.0.0-20211018074035-2e021307bc4b h1:1XF24mVaiu7u+CFywTdcDo2ie1pzzhwjt6RHqzpMU34=
 github.com/muesli/ansi v0.0.0-20211018074035-2e021307bc4b/go.mod h1:fQuZ0gauxyBcmsdE3ZT4NasjaRdxmbCS0jRHsrWu3Ho=
-github.com/muesli/cancelreader v0.2.0 h1:SOpr+CfyVNce341kKqvbhhzQhBPyJRXQaCtn03Pae1Q=
+github.com/muesli/cancelreader v0.2.1 h1:Xzd1B4U5bWQOuSKuN398MyynIGTNT89dxzpEDsalXZs=
-github.com/muesli/cancelreader v0.2.0/go.mod h1:3XuTXfFS2VjM+HTLZY9Ak0l6eUKfijIfMUZ4EgX0QYo=
+github.com/muesli/cancelreader v0.2.1/go.mod h1:3XuTXfFS2VjM+HTLZY9Ak0l6eUKfijIfMUZ4EgX0QYo=
 github.com/muesli/reflow v0.2.1-0.20210115123740-9e1d0d53df68/go.mod h1:Xk+z4oIWdQqJzsxyjgl3P22oYZnHdZ8FFTHAQQt5BMQ=
 github.com/muesli/reflow v0.3.0 h1:IFsN6K9NfGtjeggFP+68I4chLZV2yIKsXJFNZ+eWh6s=
 github.com/muesli/reflow v0.3.0/go.mod h1:pbwTDkVPibjO2kyvBQRBxTWEEGDGq0FlB1BIKtnHY/8=
 github.com/muesli/termenv v0.11.1-0.20220204035834-5ac8409525e0/go.mod h1:Bd5NYQ7pd+SrtBSrSNoBBmXlcY8+Xj4BMJgh8qcZrvs=
-github.com/muesli/termenv v0.11.1-0.20220212125758-44cd13922739 h1:QANkGiGr39l1EESqrE0gZw0/AJNYzIvoGLhIoVYtluI=
 github.com/muesli/termenv v0.11.1-0.20220212125758-44cd13922739/go.mod h1:Bd5NYQ7pd+SrtBSrSNoBBmXlcY8+Xj4BMJgh8qcZrvs=
-github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+github.com/muesli/termenv v0.12.0 h1:KuQRUE3PgxRFWhq4gHvZtPSLCGDqM5q/cYr1pZ39ytc=
+github.com/muesli/termenv v0.12.0/go.mod h1:WCCv32tusQ/EEZ5S8oUIIrC/nIuBcxCVqlN4Xfkv+7A=
 github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
-github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
-github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
 github.com/sahilm/fuzzy v0.1.0 h1:FzWGaw2Opqyu+794ZQ9SYifWv2EIXpwP4q8dY1kDAwI=
 github.com/sahilm/fuzzy v0.1.0/go.mod h1:VFvziUEIMCrT6A6tw2RFIXPXXmzXbOsSHF0DOI8ZK9Y=

key/key.go

@@ -106,7 +106,7 @@ func (b Binding) Help() Help {
 // keybindings won't be activated and won't show up in help. Keybindings are
 // enabled by default.
 func (b Binding) Enabled() bool {
-	return !b.disabled
+	return !b.disabled || b.keys == nil
 }
 
 // SetEnabled enables or disables the keybinding.

list/list.go

@@ -534,6 +534,15 @@ func (m Model) SettingFilter() bool {
 	return m.filterState == Filtering
 }
 
+// IsFiltered returns whether or not the list is currently filtered.
+// It's purely a convenience method for the following:
+//
+//	 m.FilterState() == FilterApplied
+//
+func (m Model) IsFiltered() bool {
+	return m.filterState == FilterApplied
+}
+
 // Width returns the current width setting.
 func (m Model) Width() int {
 	return m.width

textarea/textarea_test.go

@@ -0,0 +1,446 @@
+package textarea
+
+import (
+	"strings"
+	"testing"
+
+	tea "github.com/charmbracelet/bubbletea"
+)
+
+func TestNew(t *testing.T) {
+	textarea := newTextArea()
+	view := textarea.View()
+
+	if !strings.Contains(view, ">") {
+		t.Log(view)
+		t.Error("Text area did not render the prompt")
+	}
+
+	if !strings.Contains(view, "World!") {
+		t.Log(view)
+		t.Error("Text area did not render the placeholder")
+	}
+}
+
+func TestInput(t *testing.T) {
+	textarea := newTextArea()
+
+	input := "foo"
+
+	for _, k := range []rune(input) {
+		textarea, _ = textarea.Update(keyPress(k))
+	}
+
+	view := textarea.View()
+
+	if !strings.Contains(view, input) {
+		t.Log(view)
+		t.Error("Text area did not render the input")
+	}
+
+	if textarea.col != len(input) {
+		t.Log(view)
+		t.Error("Text area did not move the cursor to the correct position")
+	}
+}
+
+func TestSoftWrap(t *testing.T) {
+	textarea := newTextArea()
+	textarea.Prompt = ""
+	textarea.ShowLineNumbers = false
+	textarea.SetWidth(5)
+	textarea.SetHeight(5)
+	textarea.CharLimit = 60
+
+	textarea, _ = textarea.Update(nil)
+
+	input := "foo bar baz"
+
+	for _, k := range []rune(input) {
+		textarea, _ = textarea.Update(keyPress(k))
+	}
+
+	view := textarea.View()
+
+	for _, word := range strings.Split(input, " ") {
+		if !strings.Contains(view, word) {
+			t.Log(view)
+			t.Error("Text area did not render the input")
+		}
+	}
+
+	// Due to the word wrapping, each word will be on a new line and the
+	// text area will look like this:
+	//
+	// > foo
+	// > bar
+	// > baz█
+	//
+	// However, due to soft-wrapping the column will still be at the end of the line.
+	if textarea.row != 0 || textarea.col != len(input) {
+		t.Log(view)
+		t.Error("Text area did not move the cursor to the correct position")
+	}
+}
+
+func TestCharLimit(t *testing.T) {
+	textarea := newTextArea()
+
+	// First input (foo bar) should be accepted as it will fall within the
+	// CharLimit. Second input (baz) should not appear in the input.
+	input := []string{"foo bar", "baz"}
+	textarea.CharLimit = len(input[0])
+
+	for _, k := range []rune(strings.Join(input, " ")) {
+		textarea, _ = textarea.Update(keyPress(k))
+	}
+
+	view := textarea.View()
+	if strings.Contains(view, input[1]) {
+		t.Log(view)
+		t.Error("Text area should not include input past the character limit")
+	}
+}
+
+func TestVerticalScrolling(t *testing.T) {
+	textarea := newTextArea()
+	textarea.Prompt = ""
+	textarea.ShowLineNumbers = false
+	textarea.SetHeight(1)
+	textarea.SetWidth(20)
+	textarea.CharLimit = 100
+
+	textarea, _ = textarea.Update(nil)
+
+	input := "This is a really long line that should wrap around the text area."
+
+	for _, k := range []rune(input) {
+		textarea, _ = textarea.Update(keyPress(k))
+	}
+
+	view := textarea.View()
+
+	// The view should contain the first "line" of the input.
+	if !strings.Contains(view, "This is a really") {
+		t.Log(view)
+		t.Error("Text area did not render the input")
+	}
+
+	// But we should be able to scroll to see the next line.
+	// Let's scroll down for each line to view the full input.
+	lines := []string{
+		"long line that",
+		"should wrap around",
+		"the text area.",
+	}
+	for _, line := range lines {
+		textarea.viewport.LineDown(1)
+		view = textarea.View()
+		if !strings.Contains(view, line) {
+			t.Log(view)
+			t.Error("Text area did not render the correct scrolled input")
+		}
+	}
+}
+
+func TestWordWrapOverflowing(t *testing.T) {
+	// An interesting edge case is when the user enters many words that fill up
+	// the text area and then goes back up and inserts a few words which causes
+	// a cascading wrap and causes an overflow of the last line.
+	//
+	// In this case, we should not let the user insert more words if, after the
+	// entire wrap is complete, the last line is overflowing.
+	textarea := newTextArea()
+
+	textarea.SetHeight(3)
+	textarea.SetWidth(20)
+	textarea.CharLimit = 500
+
+	textarea, _ = textarea.Update(nil)
+
+	input := "Testing Testing Testing Testing Testing Testing Testing Testing"
+
+	for _, k := range []rune(input) {
+		textarea, _ = textarea.Update(keyPress(k))
+		textarea.View()
+	}
+
+	// We have essentially filled the text area with input.
+	// Let's see if we can cause wrapping to overflow the last line.
+	textarea.row = 0
+	textarea.col = 0
+
+	input = "Testing"
+
+	for _, k := range []rune(input) {
+		textarea, _ = textarea.Update(keyPress(k))
+		textarea.View()
+	}
+
+	lastLineWidth := textarea.LineInfo().Width
+	if lastLineWidth > 20 {
+		t.Log(lastLineWidth)
+		t.Log(textarea.View())
+		t.Fail()
+	}
+}
+
+func TestValueSoftWrap(t *testing.T) {
+	textarea := newTextArea()
+	textarea.SetWidth(16)
+	textarea.SetHeight(10)
+	textarea.CharLimit = 500
+
+	textarea, _ = textarea.Update(nil)
+
+	input := "Testing Testing Testing Testing Testing Testing Testing Testing"
+
+	for _, k := range []rune(input) {
+		textarea, _ = textarea.Update(keyPress(k))
+		textarea.View()
+	}
+
+	value := textarea.Value()
+	if value != input {
+		t.Log(value)
+		t.Log(input)
+		t.Fatal("The text area does not have the correct value")
+	}
+}
+
+func TestSetValue(t *testing.T) {
+	textarea := newTextArea()
+	textarea.SetValue(strings.Join([]string{"Foo", "Bar", "Baz"}, "\n"))
+
+	if textarea.row != 2 && textarea.col != 3 {
+		t.Log(textarea.row, textarea.col)
+		t.Fatal("Cursor Should be on row 2 column 3 after inserting 2 new lines")
+	}
+
+	value := textarea.Value()
+	if value != "Foo\nBar\nBaz" {
+		t.Fatal("Value should be Foo\nBar\nBaz")
+	}
+
+	// SetValue should reset text area
+	textarea.SetValue("Test")
+	value = textarea.Value()
+	if value != "Test" {
+		t.Log(value)
+		t.Fatal("Text area was not reset when SetValue() was called")
+	}
+}
+
+func TestInsertString(t *testing.T) {
+	textarea := newTextArea()
+
+	// Insert some text
+	input := "foo baz"
+
+	for _, k := range []rune(input) {
+		textarea, _ = textarea.Update(keyPress(k))
+	}
+
+	// Put cursor in the middle of the text
+	textarea.col = 4
+
+	textarea.InsertString("bar ")
+
+	value := textarea.Value()
+	if value != "foo bar baz" {
+		t.Log(value)
+		t.Fatal("Expected insert string to insert bar between foo and baz")
+	}
+}
+
+func TestCanHandleEmoji(t *testing.T) {
+	textarea := newTextArea()
+	input := "🧋"
+
+	for _, k := range []rune(input) {
+		textarea, _ = textarea.Update(keyPress(k))
+	}
+
+	value := textarea.Value()
+	if value != input {
+		t.Log(value)
+		t.Fatal("Expected emoji to be inserted")
+	}
+
+	input = "🧋🧋🧋"
+
+	textarea.SetValue(input)
+
+	value = textarea.Value()
+	if value != input {
+		t.Log(value)
+		t.Fatal("Expected emoji to be inserted")
+	}
+
+	if textarea.col != 3 {
+		t.Log(textarea.col)
+		t.Fatal("Expected cursor to be on the third character")
+	}
+
+	if charOffset := textarea.LineInfo().CharOffset; charOffset != 6 {
+		t.Log(charOffset)
+		t.Fatal("Expected cursor to be on the sixth character")
+	}
+}
+
+func TestVerticalNavigationKeepsCursorHorizontalPosition(t *testing.T) {
+	textarea := newTextArea()
+	textarea.SetWidth(20)
+
+	textarea.SetValue(strings.Join([]string{"你好你好", "Hello"}, "\n"))
+
+	textarea.row = 0
+	textarea.col = 2
+
+	// 你好|你好
+	// Hell|o
+	// 1234|
+
+	// Let's imagine our cursor is on the first line where the pipe is.
+	// We press the down arrow to get to the next line.
+	// The issue is that if we keep the cursor on the same column, the cursor will jump to after the `e`.
+	//
+	// 你好|你好
+	// He|llo
+	//
+	// But this is wrong because visually we were at the 4th character due to
+	// the first line containing double-width runes.
+	// We want to keep the cursor on the same visual column.
+	//
+	// 你好|你好
+	// Hell|o
+	//
+	// This test ensures that the cursor is kept on the same visual column by
+	// ensuring that the column offset goes from 2 -> 4.
+
+	lineInfo := textarea.LineInfo()
+	if lineInfo.CharOffset != 4 || lineInfo.ColumnOffset != 2 {
+		t.Log(lineInfo.CharOffset)
+		t.Log(lineInfo.ColumnOffset)
+		t.Fatal("Expected cursor to be on the fourth character because there two double width runes on the first line.")
+	}
+
+	downMsg := tea.KeyMsg{Type: tea.KeyDown, Alt: false, Runes: []rune{}}
+	textarea, _ = textarea.Update(downMsg)
+
+	lineInfo = textarea.LineInfo()
+	if lineInfo.CharOffset != 4 || lineInfo.ColumnOffset != 4 {
+		t.Log(lineInfo.CharOffset)
+		t.Log(lineInfo.ColumnOffset)
+		t.Fatal("Expected cursor to be on the fourth character because we came down from the first line.")
+	}
+}
+
+func TestVerticalNavigationShouldRememberPositionWhileTraversing(t *testing.T) {
+	textarea := newTextArea()
+	textarea.SetWidth(40)
+
+	// Let's imagine we have a text area with the following content:
+	//
+	// Hello
+	// World
+	// This is a long line.
+	//
+	// If we are at the end of the last line and go up, we should be at the end
+	// of the second line.
+	// And, if we go up again we should be at the end of the first line.
+	// But, if we go back down twice, we should be at the end of the last line
+	// again and not the fifth (length of second line) character of the last line.
+	//
+	// In other words, we should remember the last horizontal position while
+	// traversing vertically.
+
+	textarea.SetValue(strings.Join([]string{"Hello", "World", "This is a long line."}, "\n"))
+
+	// We are at the end of the last line.
+	if textarea.col != 20 || textarea.row != 2 {
+		t.Log(textarea.col)
+		t.Fatal("Expected cursor to be on the 20th character of the last line")
+	}
+
+	// Let's go up.
+	upMsg := tea.KeyMsg{Type: tea.KeyUp, Alt: false, Runes: []rune{}}
+	textarea, _ = textarea.Update(upMsg)
+
+	// We should be at the end of the second line.
+	if textarea.col != 5 || textarea.row != 1 {
+		t.Log(textarea.col)
+		t.Fatal("Expected cursor to be on the 5th character of the second line")
+	}
+
+	// And, again.
+	textarea, _ = textarea.Update(upMsg)
+
+	// We should be at the end of the first line.
+	if textarea.col != 5 || textarea.row != 0 {
+		t.Log(textarea.col)
+		t.Fatal("Expected cursor to be on the 5th character of the first line")
+	}
+
+	// Let's go down, twice.
+	downMsg := tea.KeyMsg{Type: tea.KeyDown, Alt: false, Runes: []rune{}}
+	textarea, _ = textarea.Update(downMsg)
+	textarea, _ = textarea.Update(downMsg)
+
+	// We should be at the end of the last line.
+	if textarea.col != 20 || textarea.row != 2 {
+		t.Log(textarea.col)
+		t.Fatal("Expected cursor to be on the 20th character of the last line")
+	}
+
+	// Now, for correct behavior, if we move right or left, we should forget
+	// (reset) the saved horizontal position. Since we assume the user wants to
+	// keep the cursor where it is horizontally. This is how most text areas
+	// work.
+
+	textarea, _ = textarea.Update(upMsg)
+	leftMsg := tea.KeyMsg{Type: tea.KeyLeft, Alt: false, Runes: []rune{}}
+	textarea, _ = textarea.Update(leftMsg)
+
+	if textarea.col != 4 || textarea.row != 1 {
+		t.Log(textarea.col)
+		t.Fatal("Expected cursor to be on the 5th character of the second line")
+	}
+
+	// Going down now should keep us at the 4th column since we moved left and
+	// reset the horizontal position saved state.
+	textarea, _ = textarea.Update(downMsg)
+	if textarea.col != 4 || textarea.row != 2 {
+		t.Log(textarea.col)
+		t.Fatal("Expected cursor to be on the 4th character of the last line")
+	}
+}
+
+func TestRendersEndOfLineBuffer(t *testing.T) {
+	textarea := newTextArea()
+	textarea.ShowLineNumbers = true
+	textarea.SetWidth(20)
+
+	view := textarea.View()
+	if !strings.Contains(view, "~") {
+		t.Log(view)
+		t.Fatal("Expected to see a tilde at the end of the line")
+	}
+}
+
+func newTextArea() Model {
+	textarea := New()
+
+	textarea.Prompt = "> "
+	textarea.Placeholder = "Hello, World!"
+
+	textarea.Focus()
+
+	textarea, _ = textarea.Update(nil)
+
+	return textarea
+}
+
+func keyPress(key rune) tea.Msg {
+	return tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune{key}, Alt: false}
+}