Fix a bug in SyntaxTreeVisitor to handle return statements.

--
MOS_MIGRATED_REVID=102237430

2 files changed, 10 insertions, 2 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/Parser.java b/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
index bbed96e332..67c9ceb3fb 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
@@ -43,6 +43,8 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 
+import javax.annotation.Nullable;
+
 /**
  * Recursive descent parser for LL(2) BUILD language.
  * Loosely based on Python 2 grammar.
@@ -208,12 +210,14 @@ class Parser {
       Lexer lexer,
       EventHandler eventHandler,
       CachingPackageLocator locator,
-      ValidationEnvironment validationEnvironment) {
+      @Nullable ValidationEnvironment validationEnvironment) {
     Parser parser = new Parser(lexer, eventHandler, locator, SKYLARK);
     List<Statement> statements = parser.parseFileInput();
     boolean hasSemanticalErrors = false;
     try {
-      validationEnvironment.validateAst(statements);
+      if (validationEnvironment != null) {
+        validationEnvironment.validateAst(statements);
+      }
     } catch (EvalException e) {
       // Do not report errors caused by a previous parsing error, as it has already been reported.
       if (!e.isDueToIncompleteAST()) {
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/SyntaxTreeVisitor.java b/src/main/java/com/google/devtools/build/lib/syntax/SyntaxTreeVisitor.java
index 67690617cd..2e0f19d4ff 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/SyntaxTreeVisitor.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/SyntaxTreeVisitor.java
@@ -117,6 +117,10 @@ public class SyntaxTreeVisitor {
     visitAll(node.getStatements());
   }
 
+  public void visit(ReturnStatement node) {
+    visit(node.getReturnExpression());
+  }
+
   public void visit(DictionaryLiteral node) {
     visitAll(node.getEntries());
   }