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prevara/gio/widget/editor_test.go
2025-11-30 16:45:22 +00:00

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// SPDX-License-Identifier: Unlicense OR MIT
package widget
import (
"bytes"
"fmt"
"image"
"io"
"math/rand"
"reflect"
"testing"
"testing/quick"
"time"
"unicode/utf8"
nsareg "eliasnaur.com/font/noto/sans/arabic/regular"
"eliasnaur.com/font/roboto/robotoregular"
"github.com/p9c/p9/pkg/gel/gio/f32"
"github.com/p9c/p9/pkg/gel/gio/font"
"github.com/p9c/p9/pkg/gel/gio/font/gofont"
"github.com/p9c/p9/pkg/gel/gio/font/opentype"
"github.com/p9c/p9/pkg/gel/gio/io/input"
"github.com/p9c/p9/pkg/gel/gio/io/key"
"github.com/p9c/p9/pkg/gel/gio/io/pointer"
"github.com/p9c/p9/pkg/gel/gio/io/system"
"github.com/p9c/p9/pkg/gel/gio/layout"
"github.com/p9c/p9/pkg/gel/gio/op"
"github.com/p9c/p9/pkg/gel/gio/text"
"github.com/p9c/p9/pkg/gel/gio/unit"
)
var english = system.Locale{
Language: "EN",
Direction: system.LTR,
}
// TestEditorHistory ensures that undo and redo behave correctly.
func TestEditorHistory(t *testing.T) {
e := new(Editor)
// Insert some multi-byte unicode text.
e.SetText("안П你 hello 안П你")
assertContents(t, e, "안П你 hello 안П你", 0, 0)
// Overwrite all of the text with the empty string.
e.SetCaret(0, len([]rune("안П你 hello 안П你")))
e.Insert("")
assertContents(t, e, "", 0, 0)
// Ensure that undoing the overwrite succeeds.
e.undo()
assertContents(t, e, "안П你 hello 안П你", 13, 0)
// Ensure that redoing the overwrite succeeds.
e.redo()
assertContents(t, e, "", 0, 0)
// Insert some smaller text.
e.Insert("안П你 hello")
assertContents(t, e, "안П你 hello", 9, 9)
// Replace a region in the middle of the text.
e.SetCaret(1, 5)
e.Insert("П")
assertContents(t, e, "안Пello", 2, 2)
// Replace a second region in the middle.
e.SetCaret(3, 4)
e.Insert("П")
assertContents(t, e, "안ПeПlo", 4, 4)
// Ensure both operations undo successfully.
e.undo()
assertContents(t, e, "안Пello", 4, 3)
e.undo()
assertContents(t, e, "안П你 hello", 5, 1)
// Make a new modification.
e.Insert("Something New")
// Ensure that redo history is discarded now that
// we've diverged from the linear editing history.
// This redo() call should do nothing.
text := e.Text()
start, end := e.Selection()
e.redo()
assertContents(t, e, text, start, end)
}
func assertContents(t *testing.T, e *Editor, contents string, selectionStart, selectionEnd int) {
t.Helper()
actualContents := e.Text()
if actualContents != contents {
t.Errorf("expected editor to contain %s, got %s", contents, actualContents)
}
actualStart, actualEnd := e.Selection()
if actualStart != selectionStart {
t.Errorf("expected selection start to be %d, got %d", selectionStart, actualStart)
}
if actualEnd != selectionEnd {
t.Errorf("expected selection end to be %d, got %d", selectionEnd, actualEnd)
}
}
// TestEditorReadOnly ensures that mouse and keyboard interactions with readonly
// editors do nothing but manipulate the text selection.
func TestEditorReadOnly(t *testing.T) {
r := new(input.Router)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Constraints{
Max: image.Pt(100, 100),
},
Locale: english,
Source: r.Source(),
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
fontSize := unit.Sp(10)
font := font.Font{}
e := new(Editor)
e.ReadOnly = true
e.SetText("The quick brown fox jumps over the lazy dog. We just need a few lines of text in the editor so that it can adequately test a few different modes of selection. The quick brown fox jumps over the lazy dog. We just need a few lines of text in the editor so that it can adequately test a few different modes of selection.")
cStart, cEnd := e.Selection()
if cStart != cEnd {
t.Errorf("unexpected initial caret positions")
}
gtx.Execute(key.FocusCmd{Tag: e})
layoutEditor := func() layout.Dimensions {
return e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
}
layoutEditor()
r.Frame(gtx.Ops)
gtx.Ops.Reset()
layoutEditor()
r.Frame(gtx.Ops)
gtx.Ops.Reset()
layoutEditor()
r.Frame(gtx.Ops)
// Select everything.
gtx.Ops.Reset()
r.Queue(key.Event{Name: "A", Modifiers: key.ModShortcut})
layoutEditor()
textContent := e.Text()
cStart2, cEnd2 := e.Selection()
if cStart2 > cEnd2 {
cStart2, cEnd2 = cEnd2, cStart2
}
if cEnd2 != e.Len() {
t.Errorf("expected selection to contain %d runes, got %d", e.Len(), cEnd2)
}
if cStart2 != 0 {
t.Errorf("expected selection to start at rune 0, got %d", cStart2)
}
// Type some new characters.
gtx.Ops.Reset()
r.Queue(key.EditEvent{Range: key.Range{Start: cStart2, End: cEnd2}, Text: "something else"})
e.Update(gtx)
textContent2 := e.Text()
if textContent2 != textContent {
t.Errorf("readonly editor modified by key.EditEvent")
}
// Try to delete selection.
gtx.Ops.Reset()
r.Queue(key.Event{Name: key.NameDeleteBackward})
dims := layoutEditor()
textContent2 = e.Text()
if textContent2 != textContent {
t.Errorf("readonly editor modified by delete key.Event")
}
// Click and drag from the middle of the first line
// to the center.
gtx.Ops.Reset()
r.Queue(
pointer.Event{
Kind: pointer.Press,
Buttons: pointer.ButtonPrimary,
Position: f32.Pt(float32(dims.Size.X)*.5, 5),
},
pointer.Event{
Kind: pointer.Move,
Buttons: pointer.ButtonPrimary,
Position: layout.FPt(dims.Size).Mul(.5),
},
pointer.Event{
Kind: pointer.Release,
Buttons: pointer.ButtonPrimary,
Position: layout.FPt(dims.Size).Mul(.5),
},
)
e.Update(gtx)
cStart3, cEnd3 := e.Selection()
if cStart3 == cStart2 || cEnd3 == cEnd2 {
t.Errorf("expected mouse interaction to change selection.")
}
}
func TestEditorConfigurations(t *testing.T) {
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(300, 300)),
Locale: english,
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
fontSize := unit.Sp(10)
font := font.Font{}
sentence := "\n\n\n\n\n\n\n\n\n\n\n\nthe quick brown fox jumps over the lazy dog"
runes := len([]rune(sentence))
// Ensure that both ends of the text are reachable in all permutations
// of settings that influence layout.
for _, singleLine := range []bool{true, false} {
for _, alignment := range []text.Alignment{text.Start, text.Middle, text.End} {
for _, zeroMin := range []bool{true, false} {
t.Run(fmt.Sprintf("SingleLine: %v Alignment: %v ZeroMinConstraint: %v", singleLine, alignment, zeroMin), func(t *testing.T) {
defer func() {
if err := recover(); err != nil {
t.Error(err)
}
}()
if zeroMin {
gtx.Constraints.Min = image.Point{}
} else {
gtx.Constraints.Min = gtx.Constraints.Max
}
e := new(Editor)
e.SingleLine = singleLine
e.Alignment = alignment
e.SetText(sentence)
e.SetCaret(0, 0)
dims := e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
if dims.Size.X < gtx.Constraints.Min.X || dims.Size.Y < gtx.Constraints.Min.Y {
t.Errorf("expected min size %#+v, got %#+v", gtx.Constraints.Min, dims.Size)
}
coords := e.CaretCoords()
if halfway := float32(gtx.Constraints.Min.X) * .5; !singleLine && alignment == text.Middle && !zeroMin && coords.X != halfway {
t.Errorf("expected caret X to be %f, got %f", halfway, coords.X)
}
e.SetCaret(runes, runes)
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
coords = e.CaretCoords()
if int(coords.X) > gtx.Constraints.Max.X || int(coords.Y) > gtx.Constraints.Max.Y {
t.Errorf("caret coordinates %v exceed constraints %v", coords, gtx.Constraints.Max)
}
})
}
}
}
}
func TestEditor(t *testing.T) {
e := new(Editor)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Locale: english,
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
fontSize := unit.Sp(10)
font := font.Font{}
// Regression test for bad in-cluster rune offset math.
e.SetText("æbc")
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
e.text.MoveLineEnd(selectionClear)
assertCaret(t, e, 0, 3, len("æbc"))
textSample := "æbc\naøå••"
e.SetCaret(0, 0) // shouldn't panic
assertCaret(t, e, 0, 0, 0)
e.SetText(textSample)
if got, exp := e.Len(), utf8.RuneCountInString(e.Text()); got != exp {
t.Errorf("got length %d, expected %d", got, exp)
}
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
assertCaret(t, e, 0, 0, 0)
e.text.MoveLineEnd(selectionClear)
assertCaret(t, e, 0, 3, len("æbc"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 0, len("æbc\n"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 3, len("æbc"))
e.text.MoveLines(+1, selectionClear)
assertCaret(t, e, 1, 4, len("æbc\naøå•"))
e.text.MoveLineEnd(selectionClear)
assertCaret(t, e, 1, 5, len("æbc\naøå••"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 5, len("æbc\naøå••"))
e.text.MoveLines(3, selectionClear)
e.SetCaret(0, 0)
assertCaret(t, e, 0, 0, 0)
e.SetCaret(utf8.RuneCountInString("æ"), utf8.RuneCountInString("æ"))
assertCaret(t, e, 0, 1, 2)
e.SetCaret(utf8.RuneCountInString("æbc\naøå•"), utf8.RuneCountInString("æbc\naøå•"))
assertCaret(t, e, 1, 4, len("æbc\naøå•"))
// Ensure that password masking does not affect caret behavior
e.MoveCaret(-3, -3)
assertCaret(t, e, 1, 1, len("æbc\na"))
e.text.Mask = '*'
e.Update(gtx)
assertCaret(t, e, 1, 1, len("æbc\na"))
e.MoveCaret(-3, -3)
assertCaret(t, e, 0, 2, len("æb"))
// Test that moveLine applies x offsets from previous moves.
e.SetText("long line\nshort")
e.SetCaret(0, 0)
e.text.MoveLineEnd(selectionClear)
e.text.MoveLines(+1, selectionClear)
e.text.MoveLines(-1, selectionClear)
assertCaret(t, e, 0, utf8.RuneCountInString("long line"), len("long line"))
}
var arabic = system.Locale{
Language: "AR",
Direction: system.RTL,
}
var arabicCollection = func() []font.FontFace {
parsed, _ := opentype.Parse(nsareg.TTF)
return []font.FontFace{{Font: font.Font{}, Face: parsed}}
}()
func TestEditorRTL(t *testing.T) {
e := new(Editor)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Locale: arabic,
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(arabicCollection))
fontSize := unit.Sp(10)
font := font.Font{}
e.SetCaret(0, 0) // shouldn't panic
assertCaret(t, e, 0, 0, 0)
// Set the text to a single RTL word. The caret should start at 0 column
// zero, but this is the first column on the right.
e.SetText("الحب")
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
assertCaret(t, e, 0, 0, 0)
e.MoveCaret(+1, +1)
assertCaret(t, e, 0, 1, len("ا"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 0, 2, len("ال"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 0, 3, len("الح"))
// Move to the "end" of the line. This moves to the left edge of the line.
e.text.MoveLineEnd(selectionClear)
assertCaret(t, e, 0, 4, len("الحب"))
sentence := "الحب سماء لا\nتمط غير الأحلام"
e.SetText(sentence)
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
assertCaret(t, e, 0, 0, 0)
e.text.MoveLineEnd(selectionClear)
assertCaret(t, e, 0, 12, len("الحب سماء لا"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 0, len("الحب سماء لا\n"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 1, len("الحب سماء لا\nت"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 1, 0, len("الحب سماء لا\n"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 12, len("الحب سماء لا"))
e.text.MoveLines(+1, selectionClear)
assertCaret(t, e, 1, 14, len("الحب سماء لا\nتمط غير الأحلا"))
e.text.MoveLineEnd(selectionClear)
assertCaret(t, e, 1, 15, len("الحب سماء لا\nتمط غير الأحلام"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 15, len("الحب سماء لا\nتمط غير الأحلام"))
e.text.MoveLines(3, selectionClear)
assertCaret(t, e, 1, 15, len("الحب سماء لا\nتمط غير الأحلام"))
e.SetCaret(utf8.RuneCountInString(sentence), 0)
assertCaret(t, e, 1, 15, len("الحب سماء لا\nتمط غير الأحلام"))
if selection := e.SelectedText(); selection != sentence {
t.Errorf("expected selection %s, got %s", sentence, selection)
}
e.SetCaret(0, 0)
assertCaret(t, e, 0, 0, 0)
e.SetCaret(utf8.RuneCountInString("ا"), utf8.RuneCountInString("ا"))
assertCaret(t, e, 0, 1, len("ا"))
e.SetCaret(utf8.RuneCountInString("الحب سماء لا\nتمط غ"), utf8.RuneCountInString("الحب سماء لا\nتمط غ"))
assertCaret(t, e, 1, 5, len("الحب سماء لا\nتمط غ"))
}
func TestEditorLigature(t *testing.T) {
e := new(Editor)
e.WrapPolicy = text.WrapWords
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Locale: english,
}
face, err := opentype.Parse(robotoregular.TTF)
if err != nil {
t.Skipf("failed parsing test font: %v", err)
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection([]font.FontFace{
{
Font: font.Font{
Typeface: "Roboto",
},
Face: face,
},
}))
fontSize := unit.Sp(10)
font := font.Font{}
/*
In this font, the following rune sequences form ligatures:
- ffi
- ffl
- fi
- fl
*/
e.SetCaret(0, 0) // shouldn't panic
assertCaret(t, e, 0, 0, 0)
e.SetText("fl") // just a ligature
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
e.text.MoveLineEnd(selectionClear)
assertCaret(t, e, 0, 2, len("fl"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 1, len("f"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 0, 0)
e.MoveCaret(+2, +2)
assertCaret(t, e, 0, 2, len("fl"))
e.SetText("flaffl•ffi\n•fflfi") // 3 ligatures on line 0, 2 on line 1
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
assertCaret(t, e, 0, 0, 0)
e.text.MoveLineEnd(selectionClear)
assertCaret(t, e, 0, 10, len("ffaffl•ffi"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 0, len("ffaffl•ffi\n"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 1, len("ffaffl•ffi\n•"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 2, len("ffaffl•ffi\n•f"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 3, len("ffaffl•ffi\n•ff"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 4, len("ffaffl•ffi\n•ffl"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 5, len("ffaffl•ffi\n•fflf"))
e.MoveCaret(+1, +1)
assertCaret(t, e, 1, 6, len("ffaffl•ffi\n•fflfi"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 1, 5, len("ffaffl•ffi\n•fflf"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 1, 4, len("ffaffl•ffi\n•ffl"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 1, 3, len("ffaffl•ffi\n•ff"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 1, 2, len("ffaffl•ffi\n•f"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 1, 1, len("ffaffl•ffi\n•"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 1, 0, len("ffaffl•ffi\n"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 10, len("ffaffl•ffi"))
e.MoveCaret(-2, -2)
assertCaret(t, e, 0, 8, len("ffaffl•f"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 7, len("ffaffl•"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 6, len("ffaffl"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 5, len("ffaff"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 4, len("ffaf"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 3, len("ffa"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 2, len("ff"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 1, len("f"))
e.MoveCaret(-1, -1)
assertCaret(t, e, 0, 0, 0)
gtx.Constraints = layout.Exact(image.Pt(50, 50))
e.SetText("fflffl fflffl fflffl fflffl") // Many ligatures broken across lines.
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
// Ensure that all runes in the final cluster of a line are properly
// decoded when moving to the end of the line. This is a regression test.
e.text.MoveLineEnd(selectionClear)
// The first line was broken by line wrapping, not a newline character, and has a trailing
// whitespace. However, we should never be able to reach the "other side" of such a trailing
// whitespace glyph.
assertCaret(t, e, 0, 13, len("fflffl fflffl"))
e.text.MoveLines(1, selectionClear)
assertCaret(t, e, 1, 13, len("fflffl fflffl fflffl fflffl"))
e.text.MoveLines(-1, selectionClear)
assertCaret(t, e, 0, 13, len("fflffl fflffl"))
// Absurdly narrow constraints to force each ligature onto its own line.
gtx.Constraints = layout.Exact(image.Pt(10, 10))
e.SetText("ffl ffl") // Two ligatures on separate lines.
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
assertCaret(t, e, 0, 0, 0)
e.MoveCaret(1, 1) // Move the caret into the first ligature.
assertCaret(t, e, 0, 1, len("f"))
e.MoveCaret(4, 4) // Move the caret several positions.
assertCaret(t, e, 1, 1, len("ffl f"))
}
func TestEditorDimensions(t *testing.T) {
e := new(Editor)
r := new(input.Router)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Constraints{Max: image.Pt(100, 100)},
Source: r.Source(),
Locale: english,
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
fontSize := unit.Sp(10)
font := font.Font{}
gtx.Execute(key.FocusCmd{Tag: e})
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
r.Queue(key.EditEvent{Text: "A"})
dims := e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
if dims.Size.X < 5 {
t.Errorf("EditEvent was not reflected in Editor width")
}
}
// assertCaret asserts that the editor caret is at a particular line
// and column, and that the byte position matches as well.
func assertCaret(t *testing.T, e *Editor, line, col, bytes int) {
t.Helper()
gotLine, gotCol := e.CaretPos()
if gotLine != line || gotCol != col {
t.Errorf("caret at (%d, %d), expected (%d, %d)", gotLine, gotCol, line, col)
}
caretBytes := e.text.runeOffset(e.text.caret.start)
if bytes != caretBytes {
t.Errorf("caret at buffer position %d, expected %d", caretBytes, bytes)
}
// Ensure that SelectedText() does not panic no matter what the
// editor's state is.
_ = e.SelectedText()
}
type editMutation int
const (
setText editMutation = iota
moveRune
moveLine
movePage
moveTextStart
moveTextEnd
moveLineStart
moveLineEnd
moveCoord
moveWord
deleteWord
moveLast // Mark end; never generated.
)
func TestEditorCaretConsistency(t *testing.T) {
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Locale: english,
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
fontSize := unit.Sp(10)
font := font.Font{}
for _, a := range []text.Alignment{text.Start, text.Middle, text.End} {
e := &Editor{}
e.Alignment = a
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
consistent := func() error {
t.Helper()
gotLine, gotCol := e.CaretPos()
gotCoords := e.CaretCoords()
// Blow away index to re-compute position from scratch.
e.text.invalidate()
want := e.text.closestToRune(e.text.caret.start)
wantCoords := f32.Pt(float32(want.x)/64, float32(want.y))
if want.lineCol.line != gotLine || int(want.lineCol.col) != gotCol || gotCoords != wantCoords {
return fmt.Errorf("caret (%d,%d) pos %s, want (%d,%d) pos %s",
gotLine, gotCol, gotCoords, want.lineCol.line, want.lineCol.col, wantCoords)
}
return nil
}
if err := consistent(); err != nil {
t.Errorf("initial editor inconsistency (alignment %s): %v", a, err)
}
move := func(mutation editMutation, str string, distance int8, x, y uint16) bool {
switch mutation {
case setText:
e.SetText(str)
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
case moveRune:
e.MoveCaret(int(distance), int(distance))
case moveLine:
e.text.MoveLines(int(distance), selectionClear)
case movePage:
e.text.MovePages(int(distance), selectionClear)
case moveLineStart:
e.text.MoveLineStart(selectionClear)
case moveLineEnd:
e.text.MoveLineEnd(selectionClear)
case moveTextStart:
e.text.MoveTextStart(selectionClear)
case moveTextEnd:
e.text.MoveTextEnd(selectionClear)
case moveCoord:
e.text.MoveCoord(image.Pt(int(x), int(y)))
case moveWord:
e.text.MoveWord(int(distance), selectionClear)
case deleteWord:
e.deleteWord(int(distance))
default:
return false
}
if err := consistent(); err != nil {
t.Error(err)
return false
}
return true
}
if err := quick.Check(move, nil); err != nil {
t.Errorf("editor inconsistency (alignment %s): %v", a, err)
}
}
}
func TestEditorMoveWord(t *testing.T) {
type Test struct {
Text string
Start int
Skip int
Want int
}
tests := []Test{
{"", 0, 0, 0},
{"", 0, -1, 0},
{"", 0, 1, 0},
{"hello", 0, -1, 0},
{"hello", 0, 1, 5},
{"hello world", 3, 1, 5},
{"hello world", 3, -1, 0},
{"hello world", 8, -1, 6},
{"hello world", 8, 1, 11},
{"hello world", 3, 1, 5},
{"hello world", 3, 2, 14},
{"hello world", 8, 1, 14},
{"hello world", 8, -1, 0},
{"hello brave new world", 0, 3, 15},
}
setup := func(t string) *Editor {
e := new(Editor)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Locale: english,
}
e.SetText(t)
e.Update(gtx)
return e
}
for ii, tt := range tests {
e := setup(tt.Text)
e.MoveCaret(tt.Start, tt.Start)
e.text.MoveWord(tt.Skip, selectionClear)
caretBytes := e.text.runeOffset(e.text.caret.start)
if caretBytes != tt.Want {
t.Fatalf("[%d] moveWord: bad caret position: got %d, want %d", ii, caretBytes, tt.Want)
}
}
}
func TestEditorInsert(t *testing.T) {
type Test struct {
Text string
Start int
Selection int
Insertion string
Result string
}
tests := []Test{
// Nothing inserted
{"", 0, 0, "", ""},
{"", 0, -1, "", ""},
{"", 0, 1, "", ""},
{"", 0, -2, "", ""},
{"", 0, 2, "", ""},
{"world", 0, 0, "", "world"},
{"world", 0, -1, "", "world"},
{"world", 0, 1, "", "orld"},
{"world", 2, 0, "", "world"},
{"world", 2, -1, "", "wrld"},
{"world", 2, 1, "", "wold"},
{"world", 5, 0, "", "world"},
{"world", 5, -1, "", "worl"},
{"world", 5, 1, "", "world"},
// One rune inserted
{"", 0, 0, "_", "_"},
{"", 0, -1, "_", "_"},
{"", 0, 1, "_", "_"},
{"", 0, -2, "_", "_"},
{"", 0, 2, "_", "_"},
{"world", 0, 0, "_", "_world"},
{"world", 0, -1, "_", "_world"},
{"world", 0, 1, "_", "_orld"},
{"world", 2, 0, "_", "wo_rld"},
{"world", 2, -1, "_", "w_rld"},
{"world", 2, 1, "_", "wo_ld"},
{"world", 5, 0, "_", "world_"},
{"world", 5, -1, "_", "worl_"},
{"world", 5, 1, "_", "world_"},
// More runes inserted
{"", 0, 0, "-3-", "-3-"},
{"", 0, -1, "-3-", "-3-"},
{"", 0, 1, "-3-", "-3-"},
{"", 0, -2, "-3-", "-3-"},
{"", 0, 2, "-3-", "-3-"},
{"world", 0, 0, "-3-", "-3-world"},
{"world", 0, -1, "-3-", "-3-world"},
{"world", 0, 1, "-3-", "-3-orld"},
{"world", 2, 0, "-3-", "wo-3-rld"},
{"world", 2, -1, "-3-", "w-3-rld"},
{"world", 2, 1, "-3-", "wo-3-ld"},
{"world", 5, 0, "-3-", "world-3-"},
{"world", 5, -1, "-3-", "worl-3-"},
{"world", 5, 1, "-3-", "world-3-"},
// Runes with length > 1 inserted
{"", 0, 0, "éêè", "éêè"},
{"", 0, -1, "éêè", "éêè"},
{"", 0, 1, "éêè", "éêè"},
{"", 0, -2, "éêè", "éêè"},
{"", 0, 2, "éêè", "éêè"},
{"world", 0, 0, "éêè", "éêèworld"},
{"world", 0, -1, "éêè", "éêèworld"},
{"world", 0, 1, "éêè", "éêèorld"},
{"world", 2, 0, "éêè", "woéêèrld"},
{"world", 2, -1, "éêè", "wéêèrld"},
{"world", 2, 1, "éêè", "woéêèld"},
{"world", 5, 0, "éêè", "worldéêè"},
{"world", 5, -1, "éêè", "worléêè"},
{"world", 5, 1, "éêè", "worldéêè"},
// Runes with length > 1 deleted from selection
{"élançé", 0, 1, "", "lançé"},
{"élançé", 0, 1, "-3-", "-3-lançé"},
{"élançé", 3, 2, "-3-", "éla-3-é"},
{"élançé", 3, 3, "-3-", "éla-3-"},
{"élançé", 3, 10, "-3-", "éla-3-"},
{"élançé", 5, -1, "-3-", "élan-3-é"},
{"élançé", 6, -1, "-3-", "élanç-3-"},
{"élançé", 6, -3, "-3-", "éla-3-"},
}
setup := func(t string) *Editor {
e := new(Editor)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Locale: english,
}
e.SetText(t)
e.Update(gtx)
return e
}
for ii, tt := range tests {
e := setup(tt.Text)
e.MoveCaret(tt.Start, tt.Start)
e.MoveCaret(0, tt.Selection)
e.Insert(tt.Insertion)
if e.Text() != tt.Result {
t.Fatalf("[%d] Insert: invalid result: got %q, want %q", ii, e.Text(), tt.Result)
}
}
}
func TestEditorDeleteWord(t *testing.T) {
type Test struct {
Text string
Start int
Selection int
Delete int
Want int
Result string
}
tests := []Test{
// No text selected
{"", 0, 0, 0, 0, ""},
{"", 0, 0, -1, 0, ""},
{"", 0, 0, 1, 0, ""},
{"", 0, 0, -2, 0, ""},
{"", 0, 0, 2, 0, ""},
{"hello", 0, 0, -1, 0, "hello"},
{"hello", 0, 0, 1, 0, ""},
// Document (imho) incorrect behavior w.r.t. deleting spaces following
// words.
{"hello world", 0, 0, 1, 0, " world"}, // Should be "world", if you ask me.
{"hello world", 0, 0, 2, 0, "world"}, // Should be "".
{"hello ", 0, 0, 1, 0, " "}, // Should be "".
{"hello world", 11, 0, -1, 6, "hello "}, // Should be "hello".
{"hello world", 11, 0, -2, 5, "hello"}, // Should be "".
{"hello ", 6, 0, -1, 0, ""}, // Correct result.
{"hello world", 3, 0, 1, 3, "hel world"},
{"hello world", 3, 0, -1, 0, "lo world"},
{"hello world", 8, 0, -1, 6, "hello rld"},
{"hello world", 8, 0, 1, 8, "hello wo"},
{"hello world", 3, 0, 1, 3, "hel world"},
{"hello world", 3, 0, 2, 3, "helworld"},
{"hello world", 8, 0, 1, 8, "hello "},
{"hello world", 8, 0, -1, 5, "hello world"},
{"hello brave new world", 0, 0, 3, 0, " new world"},
{"helléèçàô world", 3, 0, 1, 3, "hel world"}, // unicode char with length > 1 in deleted part
// Add selected text.
//
// Several permutations must be tested:
// - select from the left or right
// - Delete + or -
// - abs(Delete) == 1 or > 1
//
// "brave |" selected; caret at |
{"hello there brave new world", 12, 6, 1, 12, "hello there new world"}, // #16
{"hello there brave new world", 12, 6, 2, 12, "hello there world"}, // The two spaces after "there" are actually suboptimal, if you ask me. See also above cases.
{"hello there brave new world", 12, 6, -1, 12, "hello there new world"},
{"hello there brave new world", 12, 6, -2, 6, "hello new world"},
{"hello there b®âve new world", 12, 6, 1, 12, "hello there new world"}, // unicode chars with length > 1 in selection
{"hello there b®âve new world", 12, 6, 2, 12, "hello there world"}, // ditto
{"hello there b®âve new world", 12, 6, -1, 12, "hello there new world"}, // ditto
{"hello there b®âve new world", 12, 6, -2, 6, "hello new world"}, // ditto
// "|brave " selected
{"hello there brave new world", 18, -6, 1, 12, "hello there new world"}, // #20
{"hello there brave new world", 18, -6, 2, 12, "hello there world"}, // ditto
{"hello there brave new world", 18, -6, -1, 12, "hello there new world"},
{"hello there brave new world", 18, -6, -2, 6, "hello new world"},
{"hello there b®âve new world", 18, -6, 1, 12, "hello there new world"}, // unicode chars with length > 1 in selection
// Random edge cases
{"hello there brave new world", 12, 6, 99, 12, "hello there "},
{"hello there brave new world", 18, -6, -99, 0, "new world"},
}
setup := func(t string) *Editor {
e := new(Editor)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Locale: english,
}
e.SetText(t)
e.Update(gtx)
return e
}
for ii, tt := range tests {
e := setup(tt.Text)
e.MoveCaret(tt.Start, tt.Start)
e.MoveCaret(0, tt.Selection)
e.deleteWord(tt.Delete)
caretBytes := e.text.runeOffset(e.text.caret.start)
if caretBytes != tt.Want {
t.Fatalf("[%d] deleteWord: bad caret position: got %d, want %d", ii, caretBytes, tt.Want)
}
if e.Text() != tt.Result {
t.Fatalf("[%d] deleteWord: invalid result: got %q, want %q", ii, e.Text(), tt.Result)
}
}
}
func TestEditorNoLayout(t *testing.T) {
var e Editor
e.SetText("hi!\n")
e.MoveCaret(1, 1)
}
// Generate generates a value of itself, for testing/quick.
func (editMutation) Generate(rand *rand.Rand, size int) reflect.Value {
t := editMutation(rand.Intn(int(moveLast)))
return reflect.ValueOf(t)
}
// TestEditorSelect tests the selection code. It lays out an editor with several
// lines in it, selects some text, verifies the selection, resizes the editor
// to make it much narrower (which makes the lines in the editor reflow), and
// then verifies that the updated (col, line) positions of the selected text
// are where we expect.
func TestEditorSelectReflow(t *testing.T) {
e := new(Editor)
e.SetText(`a 2 4 6 8 a
b 2 4 6 8 b
c 2 4 6 8 c
d 2 4 6 8 d
e 2 4 6 8 e
f 2 4 6 8 f
g 2 4 6 8 g
`)
r := new(input.Router)
gtx := layout.Context{
Ops: new(op.Ops),
Locale: english,
Source: r.Source(),
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
font := font.Font{}
fontSize := unit.Sp(10)
var tim time.Duration
selected := func(start, end int) string {
gtx.Execute(key.FocusCmd{Tag: e})
// Layout once with no events; populate e.lines.
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
gtx.Source = r.Source()
// Build the selection events
startPos := e.text.closestToRune(start)
endPos := e.text.closestToRune(end)
r.Queue(
pointer.Event{
Buttons: pointer.ButtonPrimary,
Kind: pointer.Press,
Source: pointer.Mouse,
Time: tim,
Position: f32.Pt(textWidth(e, startPos.lineCol.line, 0, startPos.lineCol.col), textBaseline(e, startPos.lineCol.line)),
},
pointer.Event{
Kind: pointer.Release,
Source: pointer.Mouse,
Time: tim,
Position: f32.Pt(textWidth(e, endPos.lineCol.line, 0, endPos.lineCol.col), textBaseline(e, endPos.lineCol.line)),
},
)
tim += time.Second // Avoid multi-clicks.
for {
_, ok := e.Update(gtx) // throw away any events from this layout
if !ok {
break
}
}
return e.SelectedText()
}
type screenPos image.Point
logicalPosMatch := func(t *testing.T, n int, label string, expected screenPos, actual combinedPos) {
t.Helper()
if actual.lineCol.line != expected.Y || actual.lineCol.col != expected.X {
t.Errorf("Test %d: Expected %s %#v; got %#v",
n, label,
expected, actual)
}
}
type testCase struct {
// input text offsets
start, end int
// expected selected text
selection string
// expected line/col positions of selection after resize
startPos, endPos screenPos
}
for n, tst := range []testCase{
{0, 1, "a", screenPos{}, screenPos{Y: 0, X: 1}},
{0, 4, "a 2 ", screenPos{}, screenPos{Y: 0, X: 4}},
{0, 11, "a 2 4 6 8 a", screenPos{}, screenPos{Y: 1, X: 3}},
{6, 10, "6 8 ", screenPos{Y: 0, X: 6}, screenPos{Y: 1, X: 2}},
{41, 66, " 6 8 d\ne 2 4 6 8 e\nf 2 4 ", screenPos{Y: 6, X: 5}, screenPos{Y: 10, X: 6}},
} {
gtx.Constraints = layout.Exact(image.Pt(100, 100))
if got := selected(tst.start, tst.end); got != tst.selection {
t.Errorf("Test %d pt1: Expected %q, got %q", n, tst.selection, got)
continue
}
// Constrain the editor to roughly 6 columns wide and redraw
gtx.Constraints = layout.Exact(image.Pt(36, 36))
// Keep existing selection
gtx = gtx.Disabled()
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
caretStart := e.text.closestToRune(e.text.caret.start)
caretEnd := e.text.closestToRune(e.text.caret.end)
logicalPosMatch(t, n, "start", tst.startPos, caretEnd)
logicalPosMatch(t, n, "end", tst.endPos, caretStart)
}
}
func TestEditorSelectShortcuts(t *testing.T) {
tFont := font.Font{}
tFontSize := unit.Sp(10)
tShaper := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
tEditor := &Editor{
SingleLine: false,
ReadOnly: true,
}
lines := "abc abc abc\ndef def def\nghi ghi ghi"
tEditor.SetText(lines)
type testCase struct {
// Initial text selection.
startPos, endPos int
// Keyboard shortcut to execute.
keyEvent key.Event
// Expected text selection.
selection string
}
pos1, pos2 := 14, 21
for n, tst := range []testCase{
{pos1, pos2, key.Event{Name: "A", Modifiers: key.ModShortcut}, lines},
{pos2, pos1, key.Event{Name: "A", Modifiers: key.ModShortcut}, lines},
{pos1, pos2, key.Event{Name: key.NameHome, Modifiers: key.ModShift}, "def def d"},
{pos1, pos2, key.Event{Name: key.NameEnd, Modifiers: key.ModShift}, "ef"},
{pos2, pos1, key.Event{Name: key.NameHome, Modifiers: key.ModShift}, "de"},
{pos2, pos1, key.Event{Name: key.NameEnd, Modifiers: key.ModShift}, "f def def"},
{pos1, pos2, key.Event{Name: key.NameHome, Modifiers: key.ModShortcut | key.ModShift}, "abc abc abc\ndef def d"},
{pos1, pos2, key.Event{Name: key.NameEnd, Modifiers: key.ModShortcut | key.ModShift}, "ef\nghi ghi ghi"},
{pos2, pos1, key.Event{Name: key.NameHome, Modifiers: key.ModShortcut | key.ModShift}, "abc abc abc\nde"},
{pos2, pos1, key.Event{Name: key.NameEnd, Modifiers: key.ModShortcut | key.ModShift}, "f def def\nghi ghi ghi"},
} {
tRouter := new(input.Router)
gtx := layout.Context{
Ops: new(op.Ops),
Locale: english,
Constraints: layout.Exact(image.Pt(100, 100)),
Source: tRouter.Source(),
}
gtx.Execute(key.FocusCmd{Tag: tEditor})
tEditor.Layout(gtx, tShaper, tFont, tFontSize, op.CallOp{}, op.CallOp{})
tEditor.SetCaret(tst.startPos, tst.endPos)
if cStart, cEnd := tEditor.Selection(); cStart != tst.startPos || cEnd != tst.endPos {
t.Errorf("TestEditorSelect %d: initial selection", n)
}
tRouter.Queue(tst.keyEvent)
tEditor.Update(gtx)
if got := tEditor.SelectedText(); got != tst.selection {
t.Errorf("TestEditorSelect %d: Expected %q, got %q", n, tst.selection, got)
}
}
}
// Verify that an existing selection is dismissed when you press arrow keys.
func TestSelectMove(t *testing.T) {
e := new(Editor)
e.SetText(`0123456789`)
r := new(input.Router)
gtx := layout.Context{
Ops: new(op.Ops),
Locale: english,
Source: r.Source(),
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
font := font.Font{}
fontSize := unit.Sp(10)
// Layout once to populate e.lines and get focus.
gtx.Execute(key.FocusCmd{Tag: e})
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
// Set up selecton so the Editor key handler filters for all 4 directional keys.
e.SetCaret(3, 6)
gtx.Ops.Reset()
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
gtx.Ops.Reset()
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
for _, keyName := range []key.Name{key.NameLeftArrow, key.NameRightArrow, key.NameUpArrow, key.NameDownArrow} {
// Select 345
e.SetCaret(3, 6)
if expected, got := "345", e.SelectedText(); expected != got {
t.Errorf("KeyName %s, expected %q, got %q", keyName, expected, got)
}
// Press the key
r.Queue(key.Event{State: key.Press, Name: keyName})
gtx.Ops.Reset()
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
if expected, got := "", e.SelectedText(); expected != got {
t.Errorf("KeyName %s, expected %q, got %q", keyName, expected, got)
}
}
}
func TestEditor_Read(t *testing.T) {
s := "hello world"
buf := make([]byte, len(s))
e := new(Editor)
e.SetText(s)
_, err := e.Seek(0, io.SeekStart)
if err != nil {
t.Error(err)
}
n, err := io.ReadFull(e, buf)
if err != nil {
t.Error(err)
}
if got, want := n, len(s); got != want {
t.Errorf("got %d; want %d", got, want)
}
if got, want := string(buf), s; got != want {
t.Errorf("got %q; want %q", got, want)
}
}
func TestEditor_WriteTo(t *testing.T) {
s := "hello world"
var buf bytes.Buffer
e := new(Editor)
e.SetText(s)
n, err := io.Copy(&buf, e)
if err != nil {
t.Error(err)
}
if got, want := int(n), len(s); got != want {
t.Errorf("got %d; want %d", got, want)
}
if got, want := buf.String(), s; got != want {
t.Errorf("got %q; want %q", got, want)
}
}
func TestEditor_MaxLen(t *testing.T) {
e := new(Editor)
e.MaxLen = 8
e.SetText("123456789")
if got, want := e.Text(), "12345678"; got != want {
t.Errorf("editor failed to cap SetText")
}
e.SetText("2345678")
r := new(input.Router)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Source: r.Source(),
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
fontSize := unit.Sp(10)
font := font.Font{}
gtx.Execute(key.FocusCmd{Tag: e})
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
r.Queue(
key.EditEvent{Range: key.Range{Start: 0, End: 2}, Text: "1234"},
key.SelectionEvent{Start: 4, End: 4},
)
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
if got, want := e.Text(), "12345678"; got != want {
t.Errorf("editor failed to cap EditEvent")
}
if start, end := e.Selection(); start != 3 || end != 3 {
t.Errorf("editor failed to adjust SelectionEvent")
}
}
func TestEditor_Filter(t *testing.T) {
e := new(Editor)
e.Filter = "123456789"
e.SetText("abcde1234")
if got, want := e.Text(), "1234"; got != want {
t.Errorf("editor failed to filter SetText")
}
e.SetText("2345678")
r := new(input.Router)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Source: r.Source(),
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
fontSize := unit.Sp(10)
font := font.Font{}
gtx.Execute(key.FocusCmd{Tag: e})
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
r.Queue(
key.EditEvent{Range: key.Range{Start: 0, End: 0}, Text: "ab1"},
key.SelectionEvent{Start: 4, End: 4},
)
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
if got, want := e.Text(), "12345678"; got != want {
t.Errorf("editor failed to filter EditEvent")
}
if start, end := e.Selection(); start != 2 || end != 2 {
t.Errorf("editor failed to adjust SelectionEvent")
}
}
func TestEditor_Submit(t *testing.T) {
e := new(Editor)
e.Submit = true
r := new(input.Router)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Exact(image.Pt(100, 100)),
Source: r.Source(),
}
cache := text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Collection()))
fontSize := unit.Sp(10)
font := font.Font{}
gtx.Execute(key.FocusCmd{Tag: e})
e.Layout(gtx, cache, font, fontSize, op.CallOp{}, op.CallOp{})
r.Frame(gtx.Ops)
r.Queue(
key.EditEvent{Range: key.Range{Start: 0, End: 0}, Text: "ab1\n"},
)
got := []EditorEvent{}
for {
ev, ok := e.Update(gtx)
if !ok {
break
}
got = append(got, ev)
}
if got, want := e.Text(), "ab1"; got != want {
t.Errorf("editor failed to filter newline")
}
want := []EditorEvent{
ChangeEvent{},
SubmitEvent{Text: e.Text()},
}
if !reflect.DeepEqual(want, got) {
t.Errorf("editor failed to register submit")
}
}
func TestNoFilterAllocs(t *testing.T) {
b := testing.Benchmark(func(b *testing.B) {
r := new(input.Router)
e := new(Editor)
gtx := layout.Context{
Ops: new(op.Ops),
Constraints: layout.Constraints{
Max: image.Pt(100, 100),
},
Locale: english,
Source: r.Source(),
}
b.ReportAllocs()
b.ResetTimer()
for b.Loop() {
e.Update(gtx)
}
})
if allocs := b.AllocsPerOp(); allocs != 0 {
t.Fatalf("expected 0 AllocsPerOp, got %d", allocs)
}
}
// textWidth is a text helper for building simple selection events.
// It assumes single-run lines, which isn't safe with non-test text
// data.
func textWidth(e *Editor, lineNum, colStart, colEnd int) float32 {
start := e.text.closestToLineCol(lineNum, colStart)
end := e.text.closestToLineCol(lineNum, colEnd)
delta := start.x - end.x
if delta < 0 {
delta = -delta
}
return float32(delta.Round())
}
// testBaseline returns the y coordinate of the baseline for the
// given line number.
func textBaseline(e *Editor, lineNum int) float32 {
start := e.text.closestToLineCol(lineNum, 0)
return float32(start.y)
}