use lru cache

go.mod

@@ -11,8 +11,9 @@ require (
 	github.com/emirpasic/gods v1.18.1
 	github.com/google/go-cmp v0.6.0
 	github.com/google/uuid v1.4.0
+	github.com/hashicorp/golang-lru/v2 v2.0.7
+	github.com/mattn/go-runewidth v0.0.16
 	github.com/muesli/reflow v0.3.0
-	github.com/muesli/termenv v0.15.2
 	github.com/spf13/cobra v1.8.0
 	github.com/spf13/pflag v1.0.5
 	github.com/spf13/viper v1.18.2
@@ -23,7 +24,6 @@ require (
 )
 
 require (
-	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
 	github.com/charmbracelet/colorprofile v0.1.6 // indirect
 	github.com/charmbracelet/x/ansi v0.4.3 // indirect
 	github.com/charmbracelet/x/cellbuf v0.0.3 // indirect
@@ -49,8 +49,6 @@ require (
 	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
 	github.com/magiconair/properties v1.8.7 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
-	github.com/mattn/go-isatty v0.0.20 // indirect
-	github.com/mattn/go-runewidth v0.0.16 // indirect
 	github.com/mitchellh/mapstructure v1.5.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect

go.sum

@@ -1,7 +1,5 @@
 github.com/atotto/clipboard v0.1.4 h1:EH0zSVneZPSuFR11BlR9YppQTVDbh5+16AmcJi4g1z4=
 github.com/atotto/clipboard v0.1.4/go.mod h1:ZY9tmq7sm5xIbd9bOK4onWV4S6X0u6GY7Vn0Yu86PYI=
-github.com/aymanbagabas/go-osc52/v2 v2.0.1 h1:HwpRHbFMcZLEVr42D4p7XBqjyuxQH5SMiErDT4WkJ2k=
-github.com/aymanbagabas/go-osc52/v2 v2.0.1/go.mod h1:uYgXzlJ7ZpABp8OJ+exZzJJhRNQ2ASbcXHWsFqH8hp8=
 github.com/carlmjohnson/versioninfo v0.22.5 h1:O00sjOLUAFxYQjlN/bzYTuZiS0y6fWDQjMRvwtKgwwc=
 github.com/carlmjohnson/versioninfo v0.22.5/go.mod h1:QT9mph3wcVfISUKd0i9sZfVrPviHuSF+cUtLjm2WSf8=
 github.com/charmbracelet/bubbles/v2 v2.0.0-alpha.2 h1:Oevn3XNNcccbI8m6cOI6rAMsY1niKsDMv55qtejWRXE=
@@ -63,6 +61,8 @@ github.com/google/pprof v0.0.0-20210720184732-4bb14d4b1be1 h1:K6RDEckDVWvDI9JAJY
 github.com/google/pprof v0.0.0-20210720184732-4bb14d4b1be1/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/uuid v1.4.0 h1:MtMxsa51/r9yyhkyLsVeVt0B+BGQZzpQiTQ4eHZ8bc4=
 github.com/google/uuid v1.4.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
+github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
 github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
 github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
 github.com/imdario/mergo v0.3.6 h1:xTNEAn+kxVO7dTZGu0CegyqKZmoWFI0rF8UxjlB2d28=
@@ -88,8 +88,6 @@ github.com/magiconair/properties v1.8.7 h1:IeQXZAiQcpL9mgcAe1Nu6cX9LLw6ExEHKjN0V
 github.com/magiconair/properties v1.8.7/go.mod h1:Dhd985XPs7jluiymwWYZ0G4Z61jb3vdS329zhj2hYo0=
 github.com/mailru/easyjson v0.7.7 h1:UGYAvKxe3sBsEDzO8ZeWOSlIQfWFlxbzLZe7hwFURr0=
 github.com/mailru/easyjson v0.7.7/go.mod h1:xzfreul335JAWq5oZzymOObrkdz5UnU4kGfJJLY9Nlc=
-github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
-github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-runewidth v0.0.12/go.mod h1:RAqKPSqVFrSLVXbA8x7dzmKdmGzieGRCM46jaSJTDAk=
 github.com/mattn/go-runewidth v0.0.16 h1:E5ScNMtiwvlvB5paMFdw9p4kSQzbXFikJ5SQO6TULQc=
 github.com/mattn/go-runewidth v0.0.16/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
@@ -104,8 +102,6 @@ github.com/muesli/cancelreader v0.2.2 h1:3I4Kt4BQjOR54NavqnDogx/MIoWBFa0StPA8ELU
 github.com/muesli/cancelreader v0.2.2/go.mod h1:3XuTXfFS2VjM+HTLZY9Ak0l6eUKfijIfMUZ4EgX0QYo=
 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 v0.15.2 h1:GohcuySI0QmI3wN8Ok9PtKGkgkFIk7y6Vpb5PvrY+Wo=
-github.com/muesli/termenv v0.15.2/go.mod h1:Epx+iuz8sNs7mNKhxzH4fWXGNpZwUaJKRS1noLXviQ8=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
 github.com/onsi/ginkgo/v2 v2.15.0 h1:79HwNRBAZHOEwrczrgSOPy+eFTTlIGELKy5as+ClttY=
@@ -184,7 +180,6 @@ golang.org/x/sync v0.8.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.26.0 h1:KHjCJyddX0LoSTb3J+vWpupP9p0oznkqVk/IfjymZbo=
 golang.org/x/sys v0.26.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.18.0 h1:FcHjZXDMxI8mM3nwhX9HlKop4C0YQvCVCdwYl2wOtE8=

internal/viewport/viewport.go

@@ -5,10 +5,13 @@ import (
 	"github.com/charmbracelet/bubbles/v2/key"
 	tea "github.com/charmbracelet/bubbletea/v2"
 	"github.com/charmbracelet/lipgloss/v2"
+	"github.com/hashicorp/golang-lru/v2/expirable"
 	"github.com/robinovitch61/kl/internal/dev"
 	"github.com/robinovitch61/kl/internal/linebuffer"
 	"regexp"
+
 	"strings"
+	"time"
 )
 
 // Terminology:
@@ -100,7 +103,7 @@ type Model[T RenderableComparable] struct {
 	// lineBufferCache is a cache of linebuffers as calls to linebuffer.New are expensive and repeated multiple times
 	// for the same input for each Update -> View cycle at the moment. It is faster to hash the inputs and store in a
 	// map than rerun linebuffer.New multiple times
-	lineBufferCache map[string]*linebuffer.LineBuffer
+	lineBufferCache *expirable.LRU[string, *linebuffer.LineBuffer]
 }
 
 // New creates a new viewport model with reasonable defaults
@@ -113,7 +116,11 @@ func New[T RenderableComparable](width, height int) (m Model[T]) {
 	m.KeyMap = DefaultKeyMap()
 	m.continuationIndicator = "..."
 	m.footerVisible = true
-	m.lineBufferCache = make(map[string]*linebuffer.LineBuffer)
+
+	// 500 is an estimate for the max reasonable height of a terminal viewport
+	// 5 seconds expiry balances between not using too much memory and not having to recreate linebuffers too often
+	m.lineBufferCache = expirable.NewLRU[string, *linebuffer.LineBuffer](500, nil, 5*time.Second)
+
 	return m
 }
 
@@ -125,9 +132,6 @@ func (m Model[T]) Update(msg tea.Msg) (Model[T], tea.Cmd) {
 		cmds []tea.Cmd
 	)
 
-	// clear cache
-	m.lineBufferCache = make(map[string]*linebuffer.LineBuffer)
-
 	switch msg := msg.(type) {
 	case tea.KeyMsg:
 		switch {
@@ -264,9 +268,6 @@ func (m Model[T]) View() string {
 		viewString = strings.TrimSuffix(viewString, "\n")
 	}
 
-	// clear cache
-	m.lineBufferCache = make(map[string]*linebuffer.LineBuffer)
-
 	return lipgloss.NewStyle().Width(m.width).Height(m.height).Render(viewString)
 }
 
@@ -553,12 +554,12 @@ func (m *Model[T]) viewRight(n int) {
 
 func (m *Model[T]) getLineBuffer(s string, width int, continuationIndicator string) *linebuffer.LineBuffer {
 	k := fmt.Sprintf("%s-%d-%s", s, width, continuationIndicator)
-	if lb, ok := m.lineBufferCache[k]; ok {
+	if lb, ok := m.lineBufferCache.Get(k); ok {
 		lb.SeekToWidth(0)
 		return lb
 	}
 	lb := linebuffer.New(s, width, continuationIndicator)
-	m.lineBufferCache[k] = &lb
+	m.lineBufferCache.Add(k, &lb)
 	return &lb
 }