From 0db2a5f1838bf396e6d0e160095879d954dfc9ef Mon Sep 17 00:00:00 2001
From: Andreas Schildbach <andreas.schildbach@bloq.com>
Date: Wed, 30 Jan 2019 01:48:32 +0100
Subject: [PATCH] ScriptBuilder: Add createP2PKHOutputScript() helpers.

---
 .../org/bitcoinj/script/ScriptBuilder.java    | 29 +++++++++++++++----
 .../org/bitcoinj/core/TransactionTest.java    |  5 +---
 .../bitcoinj/script/ScriptPatternTest.java    |  3 +-
 .../wallet/DefaultRiskAnalysisTest.java       |  2 +-
 4 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/core/src/main/java/org/bitcoinj/script/ScriptBuilder.java b/core/src/main/java/org/bitcoinj/script/ScriptBuilder.java
index 0305c5ec..51a11b84 100644
--- a/core/src/main/java/org/bitcoinj/script/ScriptBuilder.java
+++ b/core/src/main/java/org/bitcoinj/script/ScriptBuilder.java
@@ -258,12 +258,7 @@ public class ScriptBuilder {
         if (to instanceof LegacyAddress) {
             ScriptType scriptType = to.getOutputScriptType();
             if (scriptType == ScriptType.P2PKH) {
-                // OP_DUP OP_HASH160 <pubKeyHash> OP_EQUALVERIFY OP_CHECKSIG
-                builder.op(OP_DUP);
-                builder.op(OP_HASH160);
-                builder.data(to.getHash());
-                builder.op(OP_EQUALVERIFY);
-                builder.op(OP_CHECKSIG);
+                return createP2PKHOutputScript(to.getHash());
             } else if (scriptType == ScriptType.P2SH) {
                 // OP_HASH160 <scriptHash> OP_EQUAL
                 builder.op(OP_HASH160);
@@ -438,6 +433,28 @@ public class ScriptBuilder {
         return builder.build();
     }
 
+    /**
+     * Creates a scriptPubKey that sends to the given public key hash.
+     */
+    public static Script createP2PKHOutputScript(byte[] hash) {
+        checkArgument(hash.length == LegacyAddress.LENGTH);
+        ScriptBuilder builder = new ScriptBuilder();
+        builder.op(OP_DUP);
+        builder.op(OP_HASH160);
+        builder.data(hash);
+        builder.op(OP_EQUALVERIFY);
+        builder.op(OP_CHECKSIG);
+        return builder.build();
+    }
+
+    /**
+     * Creates a scriptPubKey that sends to the given public key.
+     */
+    public static Script createP2PKHOutputScript(ECKey key) {
+        checkArgument(key.isCompressed());
+        return createP2PKHOutputScript(key.getPubKeyHash());
+    }
+
     /**
      * Creates a segwit scriptPubKey that sends to the given public key hash.
      */
diff --git a/core/src/test/java/org/bitcoinj/core/TransactionTest.java b/core/src/test/java/org/bitcoinj/core/TransactionTest.java
index 9b096709..11dc5222 100644
--- a/core/src/test/java/org/bitcoinj/core/TransactionTest.java
+++ b/core/src/test/java/org/bitcoinj/core/TransactionTest.java
@@ -337,10 +337,7 @@ public class TransactionTest {
         assertEquals("30450221008b9d1dc26ba6a9cb62127b02742fa9d754cd3bebf337f7a55d114c8e5cdd30be022040529b194ba3f9281a99f2b1c0a19c0489bc22ede944ccf4ecbab4cc618ef3ed01",
                 HEX.encode(txSig0.encodeToBitcoin()));
 
-        Script scriptCode = new ScriptBuilder()
-                .data(ScriptBuilder.createOutputScript(LegacyAddress.fromKey(netParams, key1))
-                        .getProgram())
-                .build();
+        Script scriptCode = new ScriptBuilder().data(ScriptBuilder.createP2PKHOutputScript(key1).getProgram()).build();
         assertEquals("1976a9141d0f172a0ecb48aee1be1f2687d2963ae33f71a188ac",
                 HEX.encode(scriptCode.getProgram()));
 
diff --git a/core/src/test/java/org/bitcoinj/script/ScriptPatternTest.java b/core/src/test/java/org/bitcoinj/script/ScriptPatternTest.java
index 04f737be..70c5868a 100644
--- a/core/src/test/java/org/bitcoinj/script/ScriptPatternTest.java
+++ b/core/src/test/java/org/bitcoinj/script/ScriptPatternTest.java
@@ -19,7 +19,6 @@ package org.bitcoinj.script;
 
 import com.google.common.collect.Lists;
 
-import org.bitcoinj.core.LegacyAddress;
 import org.bitcoinj.core.NetworkParameters;
 import org.bitcoinj.core.SegwitAddress;
 import org.bitcoinj.core.Sha256Hash;
@@ -39,7 +38,7 @@ public class ScriptPatternTest {
     @Test
     public void testCommonScripts() {
         assertTrue(ScriptPattern.isPayToPubKeyHash(
-                ScriptBuilder.createOutputScript(LegacyAddress.fromKey(MAINNET, keys.get(0)))
+                ScriptBuilder.createP2PKHOutputScript(keys.get(0))
         ));
         assertTrue(ScriptPattern.isPayToScriptHash(
                 ScriptBuilder.createP2SHOutputScript(2, keys)
diff --git a/core/src/test/java/org/bitcoinj/wallet/DefaultRiskAnalysisTest.java b/core/src/test/java/org/bitcoinj/wallet/DefaultRiskAnalysisTest.java
index ca530166..3f37cdd8 100644
--- a/core/src/test/java/org/bitcoinj/wallet/DefaultRiskAnalysisTest.java
+++ b/core/src/test/java/org/bitcoinj/wallet/DefaultRiskAnalysisTest.java
@@ -208,7 +208,7 @@ public class DefaultRiskAnalysisTest {
         Transaction tx = new Transaction(MAINNET);
         tx.addInput(MAINNET.getGenesisBlock().getTransactions().get(0).getOutput(0));
         // A pay to address output
-        tx.addOutput(Coin.CENT, ScriptBuilder.createOutputScript(LegacyAddress.fromKey(MAINNET, key1)));
+        tx.addOutput(Coin.CENT, ScriptBuilder.createP2PKHOutputScript(key1));
         // A pay to pubkey output
         tx.addOutput(Coin.CENT, ScriptBuilder.createOutputScript(key1));
         tx.addOutput(Coin.CENT, ScriptBuilder.createOutputScript(key1));