ScriptBuilder: Add methods opTrue() and opFalse().

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

@@ -1,5 +1,6 @@
 /*
  * Copyright 2013 Google Inc.
+ * Copyright 2018 Nicola Atzei
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -207,6 +208,40 @@ public class ScriptBuilder {
         return addChunk(index, new ScriptChunk(data.length, data));
     }
 
+    /**
+     * Adds true to the end of the program.
+     * @return this
+     */
+    public ScriptBuilder opTrue() {
+        return number(1); // it push OP_1/OP_TRUE
+    }
+
+    /**
+     * Adds true to the given index in the program.
+     * @param index at which insert true
+     * @return this
+     */
+    public ScriptBuilder opTrue(int index) {
+        return number(index, 1); // push OP_1/OP_TRUE
+    }
+
+    /**
+     * Adds false to the end of the program.
+     * @return this
+     */
+    public ScriptBuilder opFalse() {
+        return number(0); // push OP_0/OP_FALSE
+    }
+
+    /**
+     * Adds false to the given index in the program.
+     * @param index at which insert true
+     * @return this
+     */
+    public ScriptBuilder opFalse(int index) {
+        return number(index, 0); // push OP_0/OP_FALSE
+    }
+
     /** Creates a new immutable Script based on the state of the builder. */
     public Script build() {
         return new Script(chunks);

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Nicola Atzei
+ * Copyright 2018 Nicola Atzei
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,9 @@
 
 package org.bitcoinj.script;
 
+import static org.bitcoinj.script.ScriptOpCodes.OP_FALSE;
+import static org.bitcoinj.script.ScriptOpCodes.OP_TRUE;
+import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertTrue;
 
 import org.junit.Test;
@@ -31,4 +34,18 @@ public class ScriptBuilderTest {
             }
         }
     }
+
+    @Test
+    public void testOpTrue() {
+        byte[] expected = new byte[] { OP_TRUE };
+        byte[] s = new ScriptBuilder().opTrue().build().getProgram();
+        assertArrayEquals(expected, s);
+    }
+
+    @Test
+    public void testOpFalse() {
+        byte[] expected = new byte[] { OP_FALSE };
+        byte[] s = new ScriptBuilder().opFalse().build().getProgram();
+        assertArrayEquals(expected, s);
+    }
 }