ScriptBuilder: Fix number encoding for 16. It must be encoded with smallNum().

core/src/main/java/org/bitcoinj/script/ScriptBuilder.java

@@ -112,7 +112,7 @@ public class ScriptBuilder {
      * shortest encoding possible.
      */
     public ScriptBuilder number(long num) {
-        if (num >= 0 && num < 16) {
+        if (num >= 0 && num <= 16) {
             return smallNum((int) num);
         } else {
             return bigNum(num);
@@ -124,7 +124,7 @@ public class ScriptBuilder {
      * uses shortest encoding possible.
      */
     public ScriptBuilder number(int index, long num) {
-        if (num >= 0 && num < 16) {
+        if (num >= 0 && num <= 16) {
             return addChunk(index, new ScriptChunk(Script.encodeToOpN((int) num), null));
         } else {
             return bigNum(index, num);

core/src/test/java/org/bitcoinj/script/ScriptTest.java

@@ -1,6 +1,7 @@
 /*
  * Copyright 2011 Google Inc.
  * Copyright 2014 Andreas Schildbach
+ * Copyright 2017 Thomas König
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -491,4 +492,14 @@ public class ScriptTest {
             ((byte) 133) // Pushed data
         }, builder.build().getProgram());
     }
+
+    @Test
+    public void numberBuilder16() {
+        ScriptBuilder builder = new ScriptBuilder();
+        // Numbers greater than 16 must be encoded with PUSHDATA
+        builder.number(15).number(16).number(17);
+        builder.number(0, 17).number(1, 16).number(2, 15);
+        Script script = builder.build();
+        assertEquals("PUSHDATA(1)[11] 16 15 15 16 PUSHDATA(1)[11]", script.toString());
+    }
 }