Add a pretty printer for Skylark ASTs

This can be used to canonically compare ASTs for equality, e.g. in tests.

RELNOTES: None
PiperOrigin-RevId: 160283160

1 files changed, 3 insertions, 0 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/syntax/ASTNodeTest.java b/src/test/java/com/google/devtools/build/lib/syntax/ASTNodeTest.java
index 877bbe5653..651c1f11b7 100644
--- a/src/test/java/com/google/devtools/build/lib/syntax/ASTNodeTest.java
+++ b/src/test/java/com/google/devtools/build/lib/syntax/ASTNodeTest.java
@@ -15,6 +15,7 @@ package com.google.devtools.build.lib.syntax;
 
 import static org.junit.Assert.fail;
 
+import java.io.IOException;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -32,6 +33,8 @@ public class ASTNodeTest {
   public final void createNode() throws Exception  {
     node = new ASTNode() {
       @Override
+      public void prettyPrint(Appendable buffer, int indentLevel) throws IOException {}
+      @Override
       public String toString() {
         return null;
       }