test(renderer): benchmark fragmented damage planning

commit: 616526c7729897d6cd4e07aed08780bd354f5c2c
author: brice · 3mo ago · 2026-07-15 07:18 UTC
parent: ce6cefd
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

1 file · +45 -0

M pkg/renderer/benchmark_test.go +45 -0


@@ -31,6 +31,51 @@ func BenchmarkRendererFullFrameDraw(b *testing.B) {
31	31		b.ReportMetric(float64(outBytes)/float64(b.N), "outbytes/op")
32	32		}
33	33
	34	+	func BenchmarkRendererFragmentedDamage(b *testing.B) {
	35	+	const (
	36	+	width = 120
	37	+	height = 40
	38	+	)
	39	+
	40	+	baseline := NewFrame(width, height)
	41	+	markBenchmarkFrame(&baseline)
	42	+	frame := NewFrame(width, height)
	43	+	markBenchmarkFrame(&frame)
	44	+
	45	+	// Create 256 overlapping or vertically adjacent text rectangles in reverse
	46	+	// row/column order. Canonical damage planning must sort and merge these into
	47	+	// stable per-row spans before emission.
	48	+	damage := make([]Damage, 0, 256)
	49	+	for row := 15; row >= 0; row-- {
	50	+	for col := 15; col >= 0; col-- {
	51	+	x, y := col7, row2
	52	+	damage = append(damage, Damage{Kind: DamageText, X: x, Y: y, Width: 8, Height: 2})
	53	+	for dy := range 2 {
	54	+	for dx := range 8 {
	55	+	frame.Set(x+dx, y+dy, Cell{Rune: 'z', Style: DefaultStyle()})
	56	+	}
	57	+	}
	58	+	}
	59	+	}
	60	+
	61	+	r := New(Capabilities{})
	62	+	b.ReportAllocs()
	63	+	var outBytes int64
	64	+	for b.Loop() {
	65	+	// Each iteration starts with the identical pre-update terminal shadow.
	66	+	r.replaceShadow(baseline)
	67	+	out, err := r.Draw(frame, damage)
	68	+	if err != nil {
	69	+	b.Fatal(err)
	70	+	}
	71	+	if len(out) == 0 {
	72	+	b.Fatal("expected renderer output")
	73	+	}
	74	+	outBytes += int64(len(out))
	75	+	}
	76	+	b.ReportMetric(float64(outBytes)/float64(b.N), "outbytes/op")
	77	+	}
	78	+
34	79		func BenchmarkRendererScrollFastPath(b *testing.B) {
35	80		frame := NewFrame(120, 40)
36	81		markBenchmarkFrame(&frame)


@@ -31,6 +31,51 @@ func BenchmarkRendererFullFrameDraw(b *testing.B) {
31	b.ReportMetric(float64(outBytes)/float64(b.N), "outbytes/op")	31		b.ReportMetric(float64(outBytes)/float64(b.N), "outbytes/op")
32	}	32		}
33		33
		34	+	func BenchmarkRendererFragmentedDamage(b *testing.B) {
		35	+	const (
		36	+	width = 120
		37	+	height = 40
		38	+	)
		39	+
		40	+	baseline := NewFrame(width, height)
		41	+	markBenchmarkFrame(&baseline)
		42	+	frame := NewFrame(width, height)
		43	+	markBenchmarkFrame(&frame)
		44	+
		45	+	// Create 256 overlapping or vertically adjacent text rectangles in reverse
		46	+	// row/column order. Canonical damage planning must sort and merge these into
		47	+	// stable per-row spans before emission.
		48	+	damage := make([]Damage, 0, 256)
		49	+	for row := 15; row >= 0; row-- {
		50	+	for col := 15; col >= 0; col-- {
		51	+	x, y := col7, row2
		52	+	damage = append(damage, Damage{Kind: DamageText, X: x, Y: y, Width: 8, Height: 2})
		53	+	for dy := range 2 {
		54	+	for dx := range 8 {
		55	+	frame.Set(x+dx, y+dy, Cell{Rune: 'z', Style: DefaultStyle()})
		56	+	}
		57	+	}
		58	+	}
		59	+	}
		60	+
		61	+	r := New(Capabilities{})
		62	+	b.ReportAllocs()
		63	+	var outBytes int64
		64	+	for b.Loop() {
		65	+	// Each iteration starts with the identical pre-update terminal shadow.
		66	+	r.replaceShadow(baseline)
		67	+	out, err := r.Draw(frame, damage)
		68	+	if err != nil {
		69	+	b.Fatal(err)
		70	+	}
		71	+	if len(out) == 0 {
		72	+	b.Fatal("expected renderer output")
		73	+	}
		74	+	outBytes += int64(len(out))
		75	+	}
		76	+	b.ReportMetric(float64(outBytes)/float64(b.N), "outbytes/op")
		77	+	}
		78	+
34	func BenchmarkRendererScrollFastPath(b *testing.B) {	79		func BenchmarkRendererScrollFastPath(b *testing.B) {
35	frame := NewFrame(120, 40)	80		frame := NewFrame(120, 40)
36	markBenchmarkFrame(&frame)	81		markBenchmarkFrame(&frame)