From e4118c914fb8cdcced379a41b62f95402796cbed Mon Sep 17 00:00:00 2001
From: Dave Collins <davec@conformal.com>
Date: Wed, 13 Mar 2019 01:11:49 -0500
Subject: [PATCH] txscript: Add benchmark for IsNullData

---
 txscript/bench_test.go | 15 +++++++++++++++
 txscript/script.go     | 10 ++++++++++
 2 files changed, 25 insertions(+)

diff --git a/txscript/bench_test.go b/txscript/bench_test.go
index 529d32f7..fda83771 100644
--- a/txscript/bench_test.go
+++ b/txscript/bench_test.go
@@ -312,3 +312,18 @@ func BenchmarkIsWitnessScriptHash(b *testing.B) {
 		_ = IsPayToWitnessScriptHash(script)
 	}
 }
+
+// BenchmarkIsNullDataScript benchmarks how long it takes to analyze a very
+// large script to determine if it is a standard nulldata script.
+func BenchmarkIsNullDataScript(b *testing.B) {
+	script, err := genComplexScript()
+	if err != nil {
+		b.Fatalf("failed to create benchmark script: %v", err)
+	}
+
+	b.ResetTimer()
+	b.ReportAllocs()
+	for i := 0; i < b.N; i++ {
+		_ = IsNullData(script)
+	}
+}
diff --git a/txscript/script.go b/txscript/script.go
index 5968cec7..7f812207 100644
--- a/txscript/script.go
+++ b/txscript/script.go
@@ -151,6 +151,16 @@ func isWitnessProgram(pops []parsedOpcode) bool {
 		(len(pops[1].data) >= 2 && len(pops[1].data) <= 40)
 }
 
+// IsNullData returns true if the passed script is a null data script, false
+// otherwise.
+func IsNullData(script []byte) bool {
+	pops, err := parseScript(script)
+	if err != nil {
+		return false
+	}
+	return isNullData(pops)
+}
+
 // ExtractWitnessProgramInfo attempts to extract the witness program version,
 // as well as the witness program itself from the passed script.
 func ExtractWitnessProgramInfo(script []byte) (int, []byte, error) {