JS backend: added visitors with context

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/ChameleonJsExpression.java

@@ -51,4 +51,9 @@ public class ChameleonJsExpression implements JsExpression {
     public JsExpression source(Object info) {
         return expression.source(info);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext visitor, JsContext ctx) {
+        expression.traverse(visitor, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsArrayAccess.java

@@ -46,4 +46,13 @@ public final class JsArrayAccess extends JsExpressionImpl {
         visitor.accept(arrayExpression);
         visitor.accept(indexExpression);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            arrayExpression = v.accept(arrayExpression);
+            indexExpression = v.accept(indexExpression);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsArrayLiteral.java

@@ -35,4 +35,12 @@ public final class JsArrayLiteral extends JsLiteral {
     public void acceptChildren(JsVisitor visitor) {
         visitor.acceptWithInsertRemove(expressions);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            v.acceptList(expressions);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsBinaryOperation.java

@@ -48,4 +48,17 @@ public final class JsBinaryOperation extends JsExpressionImpl {
         }
         visitor.accept(arg2);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            if (op.isAssignment()) {
+                arg1 = v.acceptLvalue(arg1);
+            } else {
+                arg1 = v.accept(arg1);
+            }
+            arg2 = v.accept(arg2);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsBlock.java

@@ -7,8 +7,6 @@ package com.google.dart.compiler.backend.js.ast;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.Collections;
 import java.util.List;
 
 /**
@@ -56,4 +54,12 @@ public class JsBlock extends SourceInfoAwareJsNode implements JsStatement {
     public void acceptChildren(JsVisitor visitor) {
         visitor.acceptWithInsertRemove(statements);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            v.acceptStatementList(statements);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsBreak.java

@@ -20,4 +20,10 @@ public final class JsBreak extends JsContinue {
     public void accept(JsVisitor v) {
         v.visitBreak(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        v.visit(this, ctx);
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsCase.java

@@ -32,4 +32,13 @@ public final class JsCase extends JsSwitchMember {
         visitor.accept(caseExpression);
         super.acceptChildren(visitor);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            caseExpression = v.accept(caseExpression);
+            v.acceptStatementList(statements);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsCatch.java

@@ -60,4 +60,16 @@ public class JsCatch extends SourceInfoAwareJsNode implements HasCondition {
         }
         visitor.accept(body);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            param = v.accept(param);
+            if (condition != null) {
+                condition = v.accept(condition);
+            }
+            body = v.accept(body);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsConditional.java

@@ -53,4 +53,14 @@ public final class JsConditional extends JsExpressionImpl {
         visitor.accept(thenExpression);
         visitor.accept(elseExpression);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            testExpression = v.accept(testExpression);
+            thenExpression = v.accept(thenExpression);
+            elseExpression = v.accept(elseExpression);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsContext.java

@@ -4,6 +4,8 @@
 
 package com.google.dart.compiler.backend.js.ast;
 
+import org.jetbrains.annotations.Nullable;
+
 /**
  * The context in which a JsNode visitation occurs. This represents the set of
  * possible operations a JsVisitor subclass can perform on the currently visited
@@ -23,4 +25,7 @@ public interface JsContext {
   void removeMe();
 
   void replaceMe(JsNode node);
+
+  @Nullable
+  JsNode getCurrentNode();
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsContinue.java

@@ -26,4 +26,10 @@ public class JsContinue extends SourceInfoAwareJsNode implements JsStatement {
     public void accept(JsVisitor v) {
         v.visitContinue(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        v.visit(this, ctx);
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsDebugger.java

@@ -20,4 +20,10 @@ public class JsDebugger extends SourceInfoAwareJsNode implements JsStatement {
     public void acceptChildren(JsVisitor visitor) {
 
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        v.visit(this, ctx);
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsDefault.java

@@ -12,4 +12,12 @@ public final class JsDefault extends JsSwitchMember {
     public void accept(JsVisitor v) {
         v.visitDefault(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            v.acceptStatementList(statements);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsDoWhile.java

@@ -19,4 +19,13 @@ public class JsDoWhile extends JsWhile {
     public void accept(JsVisitor v) {
         v.visitDoWhile(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            body = v.acceptStatement(body);
+            condition = v.accept(condition);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsDocComment.java

@@ -26,4 +26,8 @@ public class JsDocComment extends JsExpressionImpl {
     public void accept(JsVisitor v) {
         v.visitDocComment(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsEmpty.java

@@ -12,4 +12,10 @@ public class JsEmpty extends SourceInfoAwareJsNode implements JsStatement {
     public void accept(JsVisitor v) {
         v.visitEmpty(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        v.visit(this, ctx);
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsEmptyExpression.java

@@ -33,4 +33,9 @@ public class JsEmptyExpression extends JsExpressionImpl {
     public void accept(JsVisitor visitor) {
         throw new IllegalArgumentException("empty expression should not be here during generating Javascript code");
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext visitor, JsContext ctx) {
+        throw new IllegalArgumentException("empty expression should not be here during generating Javascript code");
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsExpressionStatement.java

@@ -39,4 +39,12 @@ public final class JsExpressionStatement extends AbstractNode implements JsState
     public JsNode source(Object info) {
         throw new IllegalStateException("You must not set source info for JsExpressionStatement, set for expression");
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            expression = v.accept(expression);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsFor.java

@@ -95,4 +95,27 @@ public class JsFor extends SourceInfoAwareJsNode implements JsStatement {
         }
         visitor.accept(body);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            assert (!(initExpression != null && initVars != null));
+
+            if (initExpression != null) {
+                initExpression = v.accept(initExpression);
+            } else if (initVars != null) {
+                initVars = v.accept(initVars);
+            }
+
+            if (condition != null) {
+                condition = v.accept(condition);
+            }
+
+            if (incrementExpression != null) {
+                incrementExpression = v.accept(incrementExpression);
+            }
+            body = v.acceptStatement(body);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsForIn.java

@@ -61,4 +61,16 @@ public class JsForIn extends SourceInfoAwareJsNode implements JsStatement {
         visitor.accept(objectExpression);
         visitor.accept(body);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            if (iterExpression != null) {
+                iterExpression = v.acceptLvalue(iterExpression);
+            }
+            objectExpression = v.accept(objectExpression);
+            body = v.acceptStatement(body);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsFunction.java

@@ -76,7 +76,16 @@ public final class JsFunction extends JsLiteral implements HasName {
 
     @Override
     public void acceptChildren(JsVisitor visitor) {
-        visitor.acceptWithInsertRemove(params);
+        visitor.acceptWithInsertRemove(getParameters());
         visitor.accept(body);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            v.acceptList(getParameters());
+            body = v.accept(body);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsIf.java

@@ -63,4 +63,16 @@ public final class JsIf extends SourceInfoAwareJsNode implements JsStatement {
             visitor.accept(elseStatement);
         }
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            ifExpression = v.accept(ifExpression);
+            thenStatement = v.acceptStatement(thenStatement);
+            if (elseStatement != null) {
+                elseStatement = v.acceptStatement(elseStatement);
+            }
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsInvocation.java

@@ -8,7 +8,6 @@ import com.intellij.util.SmartList;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.List;
 
 public final class JsInvocation extends JsExpressionImpl.JsExpressionHasArguments {
@@ -60,4 +59,13 @@ public final class JsInvocation extends JsExpressionImpl.JsExpressionHasArgument
         visitor.accept(qualifier);
         visitor.acceptList(arguments);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            qualifier = v.accept(qualifier);
+            v.acceptList(arguments);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsLabel.java

@@ -50,4 +50,12 @@ public class JsLabel extends SourceInfoAwareJsNode implements JsStatement, HasNa
     public void acceptChildren(JsVisitor visitor) {
         visitor.accept(statement);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            statement = v.acceptStatement(statement);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsLiteral.java

@@ -26,24 +26,36 @@ public abstract class JsLiteral extends JsExpressionImpl {
         public void accept(JsVisitor v) {
             v.visitThis(this);
         }
+
+        @Override
+        public void traverse(JsVisitorWithContext v, JsContext ctx) {
+            v.visit(this, ctx);
+            v.endVisit(this, ctx);
+        }
     }
 
     public static final class JsBooleanLiteral extends JsValueLiteral {
-      private final boolean value;
+        private final boolean value;
 
-      // Should be interned by JsProgram
-      private JsBooleanLiteral(boolean value) {
+        // Should be interned by JsProgram
+        private JsBooleanLiteral(boolean value) {
         this.value = value;
       }
 
-      public boolean getValue() {
+        public boolean getValue() {
         return value;
       }
 
-      @Override
-      public void accept(JsVisitor v) {
+        @Override
+        public void accept(JsVisitor v) {
         v.visitBoolean(this);
       }
+
+        @Override
+        public void traverse(JsVisitorWithContext v, JsContext ctx) {
+            v.visit(this, ctx);
+            v.endVisit(this, ctx);
+        }
     }
 
     /**

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsNameRef.java

@@ -79,4 +79,14 @@ public final class JsNameRef extends JsExpressionImpl implements HasName {
            visitor.accept(qualifier);
         }
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            if (qualifier != null) {
+                qualifier = v.accept(qualifier);
+            }
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsNew.java

@@ -34,4 +34,13 @@ public final class JsNew extends JsExpressionImpl.JsExpressionHasArguments {
         visitor.accept(constructorExpression);
         visitor.acceptList(arguments);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            constructorExpression = v.accept(constructorExpression);
+            v.acceptList(arguments);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsNode.java

@@ -27,4 +27,12 @@ public interface JsNode {
     void setSource(Object info);
 
     JsNode source(Object info);
+
+    /**
+     * Causes this object to have the visitor visit itself and its children.
+     *
+     * @param visitor the visitor that should traverse this node
+     * @param ctx the context of an existing traversal
+     */
+    void traverse(JsVisitorWithContext visitor, JsContext ctx);
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsNullLiteral.java

@@ -12,4 +12,10 @@ public final class JsNullLiteral extends JsLiteral.JsValueLiteral {
     public void accept(JsVisitor v) {
         v.visitNull(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        v.visit(this, ctx);
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsNumberLiteral.java

@@ -22,6 +22,12 @@ public abstract class JsNumberLiteral extends JsLiteral.JsValueLiteral {
         public String toString() {
             return String.valueOf(value);
         }
+
+        @Override
+        public void traverse(JsVisitorWithContext v, JsContext ctx) {
+            v.visit(this, ctx);
+            v.endVisit(this, ctx);
+        }
     }
 
     public static final class JsIntLiteral extends JsNumberLiteral {
@@ -39,5 +45,11 @@ public abstract class JsNumberLiteral extends JsLiteral.JsValueLiteral {
         public String toString() {
             return String.valueOf(value);
         }
+
+        @Override
+        public void traverse(JsVisitorWithContext v, JsContext ctx) {
+            v.visit(this, ctx);
+            v.endVisit(this, ctx);
+        }
     }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsObjectLiteral.java

@@ -47,4 +47,12 @@ public final class JsObjectLiteral extends JsLiteral {
     public void acceptChildren(JsVisitor visitor) {
         visitor.acceptWithInsertRemove(properties);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            v.acceptList(properties);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsParameter.java

@@ -34,4 +34,10 @@ public final class JsParameter extends SourceInfoAwareJsNode implements HasName
     public void accept(JsVisitor v) {
         v.visitParameter(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        v.visit(this, ctx);
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsPostfixOperation.java

@@ -17,4 +17,12 @@ public final class JsPostfixOperation extends JsUnaryOperation {
   public void accept(JsVisitor v) {
     v.visitPostfixOperation(this);
   }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            super.traverse(v, ctx);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsPrefixOperation.java

@@ -17,4 +17,12 @@ public final class JsPrefixOperation extends JsUnaryOperation {
     public void accept(JsVisitor v) {
         v.visitPrefixOperation(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            super.traverse(v, ctx);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsProgram.java

@@ -129,4 +129,14 @@ public final class JsProgram extends SourceInfoAwareJsNode {
             visitor.accept(fragment);
         }
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            for (JsProgramFragment fragment : fragments) {
+                v.accept(fragment);
+            }
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsProgramFragment.java

@@ -27,4 +27,12 @@ public class JsProgramFragment extends SourceInfoAwareJsNode {
     public void acceptChildren(JsVisitor visitor) {
         visitor.accept(globalBlock);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            v.accept(globalBlock);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsPropertyInitializer.java

@@ -44,4 +44,13 @@ public class JsPropertyInitializer extends SourceInfoAwareJsNode {
         visitor.accept(labelExpr);
         visitor.accept(valueExpr);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            labelExpr = v.accept(labelExpr);
+            valueExpr = v.accept(valueExpr);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsRegExp.java

@@ -31,4 +31,10 @@ public final class JsRegExp extends JsLiteral.JsValueLiteral {
     public void accept(JsVisitor v) {
         v.visitRegExp(this);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        v.visit(this, ctx);
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsReturn.java

@@ -36,4 +36,14 @@ public final class JsReturn extends SourceInfoAwareJsNode implements JsStatement
             visitor.accept(expression);
         }
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            if (expression != null) {
+                expression = v.accept(expression);
+            }
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsStringLiteral.java

@@ -6,14 +6,14 @@ package com.google.dart.compiler.backend.js.ast;
 
 public final class JsStringLiteral extends JsLiteral.JsValueLiteral {
 
-  private final String value;
+    private final String value;
 
-  // These only get created by JsProgram so that they can be interned.
-  JsStringLiteral(String value) {
+    // These only get created by JsProgram so that they can be interned.
+    JsStringLiteral(String value) {
     this.value = value;
   }
 
-  public String getValue() {
+    public String getValue() {
     return value;
   }
 
@@ -21,4 +21,10 @@ public final class JsStringLiteral extends JsLiteral.JsValueLiteral {
   public void accept(JsVisitor v) {
     v.visitString(this);
   }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        v.visit(this, ctx);
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsSwitch.java

@@ -41,4 +41,13 @@ public class JsSwitch extends SourceInfoAwareJsNode implements JsStatement {
         visitor.accept(expression);
         visitor.acceptWithInsertRemove(cases);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            expression = v.accept(expression);
+            v.acceptList(cases);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsThrow.java

@@ -31,4 +31,12 @@ public class JsThrow extends SourceInfoAwareJsNode implements JsStatement {
     public void acceptChildren(JsVisitor visitor) {
         visitor.accept(expression);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            expression = v.accept(expression);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsTry.java

@@ -60,4 +60,16 @@ public class JsTry extends SourceInfoAwareJsNode implements JsStatement {
            visitor.accept(finallyBlock);
         }
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            tryBlock = v.accept(tryBlock);
+            v.acceptList(catches);
+            if (finallyBlock != null) {
+                finallyBlock = v.accept(finallyBlock);
+            }
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsUnaryOperation.java

@@ -43,4 +43,17 @@ public abstract class JsUnaryOperation extends JsExpressionImpl {
             visitor.accept(arg);
         }
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (op.isModifying()) {
+      /*
+       * The delete operator is practically like an assignment of undefined, so for practical
+       * purposes we're treating it as an lvalue.
+       */
+            arg = v.acceptLvalue(arg);
+        } else {
+            arg = v.accept(arg);
+        }
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsVars.java

@@ -88,6 +88,16 @@ public class JsVars extends SourceInfoAwareJsNode implements JsStatement, Iterab
                 visitor.accept(initExpression);
             }
         }
+
+        @Override
+        public void traverse(JsVisitorWithContext v, JsContext ctx) {
+            if (v.visit(this, ctx)) {
+                if (initExpression != null) {
+                    initExpression = v.accept(initExpression);
+                }
+            }
+            v.endVisit(this, ctx);
+        }
     }
 
     public void add(JsVar var) {
@@ -126,4 +136,12 @@ public class JsVars extends SourceInfoAwareJsNode implements JsStatement, Iterab
     public void acceptChildren(JsVisitor visitor) {
         visitor.acceptWithInsertRemove(vars);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            v.acceptList(vars);
+        }
+        v.endVisit(this, ctx);
+    }
 }

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsVisitorWithContext.java

@@ -0,0 +1,366 @@
+/*
+ * Copyright 2008 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package com.google.dart.compiler.backend.js.ast;
+
+/**
+ * Taken from GWT project with modifications.
+ * Original:
+ *  repository: https://gwt.googlesource.com/gwt
+ *  revision: e32bf0a95029165d9e6ab457c7ee7ca8b07b908c
+ *  file: dev/core/src/com/google/gwt/dev/js/ast/JsVisitor.java
+ */
+
+import java.util.List;
+
+/**
+ * Implemented by nodes that will visit child nodes.
+ */
+@SuppressWarnings("UnusedParameters")
+public abstract class JsVisitorWithContext {
+
+    public final <T extends JsNode> T accept(T node) {
+        return doAccept(node);
+    }
+
+    public JsExpression acceptLvalue(JsExpression expr) {
+        return doAcceptLvalue(expr);
+    }
+
+    public final <T extends JsNode> void acceptList(List<T> collection) {
+        doAcceptList(collection);
+    }
+
+    public final <T extends JsStatement> T acceptStatement(T statement) {
+        //noinspection unchecked
+        return (T) doAcceptStatement(statement);
+    }
+
+    public final <T extends JsStatement> void acceptStatementList(List<T> statements) {
+        doAcceptStatementList(statements);
+    }
+
+    public void endVisit(JsArrayAccess x, JsContext ctx) {
+    }
+
+    public void endVisit(JsArrayLiteral x, JsContext ctx) {
+    }
+
+    public void endVisit(JsBinaryOperation x, JsContext ctx) {
+    }
+
+    public void endVisit(JsBlock x, JsContext ctx) {
+    }
+
+    public void endVisit(JsLiteral.JsBooleanLiteral x, JsContext ctx) {
+    }
+
+    public void endVisit(JsBreak x, JsContext ctx) {
+    }
+
+    public void endVisit(JsCase x, JsContext ctx) {
+    }
+
+    public void endVisit(JsCatch x, JsContext ctx) {
+    }
+
+    public void endVisit(JsConditional x, JsContext ctx) {
+    }
+
+    public void endVisit(JsContinue x, JsContext ctx) {
+    }
+
+    public void endVisit(JsDebugger x, JsContext ctx) {
+    }
+
+    public void endVisit(JsDefault x, JsContext ctx) {
+    }
+
+    public void endVisit(JsDoWhile x, JsContext ctx) {
+    }
+
+    public void endVisit(JsEmpty x, JsContext ctx) {
+    }
+
+    public void endVisit(JsExpressionStatement x, JsContext ctx) {
+    }
+
+    public void endVisit(JsFor x, JsContext ctx) {
+    }
+
+    public void endVisit(JsForIn x, JsContext ctx) {
+    }
+
+    public void endVisit(JsFunction x, JsContext ctx) {
+    }
+
+    public void endVisit(JsIf x, JsContext ctx) {
+    }
+
+    public void endVisit(JsInvocation x, JsContext ctx) {
+    }
+
+    public void endVisit(JsLabel x, JsContext ctx) {
+    }
+
+    public void endVisit(JsName x, JsContext ctx) {
+    }
+
+    public void endVisit(JsNameRef x, JsContext ctx) {
+    }
+
+    public void endVisit(JsNew x, JsContext ctx) {
+    }
+
+    public void endVisit(JsNullLiteral x, JsContext ctx) {
+    }
+
+    public void endVisit(JsNumberLiteral x, JsContext ctx) {
+    }
+
+    public void endVisit(JsObjectLiteral x, JsContext ctx) {
+    }
+
+    public void endVisit(JsParameter x, JsContext ctx) {
+    }
+
+    public void endVisit(JsPostfixOperation x, JsContext ctx) {
+    }
+
+    public void endVisit(JsPrefixOperation x, JsContext ctx) {
+    }
+
+    public void endVisit(JsProgram x, JsContext ctx) {
+    }
+
+    public void endVisit(JsProgramFragment x, JsContext ctx) {
+    }
+
+    public void endVisit(JsPropertyInitializer x, JsContext ctx) {
+    }
+
+    public void endVisit(JsRegExp x, JsContext ctx) {
+    }
+
+    public void endVisit(JsReturn x, JsContext ctx) {
+    }
+
+    public void endVisit(JsStringLiteral x, JsContext ctx) {
+    }
+
+    public void endVisit(JsSwitch x, JsContext ctx) {
+    }
+
+    public void endVisit(JsLiteral.JsThisRef x, JsContext ctx) {
+    }
+
+    public void endVisit(JsThrow x, JsContext ctx) {
+    }
+
+    public void endVisit(JsTry x, JsContext ctx) {
+    }
+
+    public void endVisit(JsVars.JsVar x, JsContext ctx) {
+    }
+
+    public void endVisit(JsVars x, JsContext ctx) {
+    }
+
+    public void endVisit(JsWhile x, JsContext ctx) {
+    }
+
+    public boolean visit(JsArrayAccess x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsArrayLiteral x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsBinaryOperation x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsBlock x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsLiteral.JsBooleanLiteral x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsBreak x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsCase x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsCatch x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsConditional x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsContinue x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsDebugger x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsDefault x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsDoWhile x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsEmpty x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsExpressionStatement x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsFor x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsForIn x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsFunction x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsIf x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsInvocation x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsLabel x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsName x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsNameRef x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsNew x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsNullLiteral x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsNumberLiteral x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsObjectLiteral x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsParameter x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsPostfixOperation x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsPrefixOperation x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsProgram x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsProgramFragment x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsPropertyInitializer x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsRegExp x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsReturn x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsStringLiteral x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsSwitch x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsLiteral.JsThisRef x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsThrow x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsTry x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsVars.JsVar x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsVars x, JsContext ctx) {
+        return true;
+    }
+
+    public boolean visit(JsWhile x, JsContext ctx) {
+        return true;
+    }
+
+    protected abstract  <T extends JsNode> T doAccept(T node);
+
+    protected abstract JsExpression doAcceptLvalue(JsExpression expr);
+
+    protected abstract <T extends JsNode> void doAcceptList(List<T> collection);
+
+    protected abstract <T extends JsStatement> JsStatement doAcceptStatement(T statement);
+
+    protected abstract <T extends JsStatement> void doAcceptStatementList(List<T> statements);
+
+    protected abstract <T extends JsNode> void doTraverse(T node, JsContext ctx) ;
+}

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsVisitorWithContextImpl.java

@@ -0,0 +1,210 @@
+/*
+ * Copyright 2008 Google Inc.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+
+package com.google.dart.compiler.backend.js.ast;
+
+/**
+ * Taken from GWT project with modifications.
+ * Original:
+ *  repository: https://gwt.googlesource.com/gwt
+ *  revision: e32bf0a95029165d9e6ab457c7ee7ca8b07b908c
+ *  file: dev/core/src/com/google/gwt/dev/js/ast/JsModVisitor.java
+ */
+
+import com.intellij.util.SmartList;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.List;
+import java.util.Stack;
+
+/**
+ * A visitor for iterating through and modifying an AST.
+ */
+public class JsVisitorWithContextImpl extends JsVisitorWithContext {
+
+    private final Stack<JsContext> statementContexts = new Stack<JsContext>();
+
+    public class ListContext<T extends JsNode> implements JsContext {
+        private List<T> collection;
+        private int index;
+
+        @Override
+        public boolean canInsert() {
+            return true;
+        }
+
+        @Override
+        public boolean canRemove() {
+            return true;
+        }
+
+        @Override
+        public void insertAfter(JsNode node) {
+            //noinspection unchecked
+            collection.add(index + 1, (T) node);
+        }
+
+        @Override
+        public void insertBefore(JsNode node) {
+            //noinspection unchecked
+            collection.add(index++, (T) node);
+        }
+
+        @Override
+        public boolean isLvalue() {
+            return false;
+        }
+
+        @Override
+        public void removeMe() {
+            collection.remove(index--);
+        }
+
+        @Override
+        public void replaceMe(JsNode node) {
+            checkReplacement(collection.get(index), node);
+            //noinspection unchecked
+            collection.set(index, (T) node);
+        }
+        
+        @Nullable
+        @Override
+        public JsNode getCurrentNode() {
+            if (index < collection.size()) {
+                return collection.get(index);
+            }
+
+            return null;
+        }
+
+        protected void traverse(List<T> collection) {
+            this.collection = collection;
+            for (index = 0; index < collection.size(); ++index) {
+                T node = collection.get(index);
+                doTraverse(node, this);
+            }
+        }
+    }
+
+    private class LvalueContext extends NodeContext<JsExpression> {
+        @Override
+        public boolean isLvalue() {
+            return true;
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    private class NodeContext<T extends JsNode> implements JsContext {
+        protected T node;
+
+        @Override
+        public boolean canInsert() {
+            return false;
+        }
+
+        @Override
+        public boolean canRemove() {
+            return false;
+        }
+
+        @Override
+        public void insertAfter(JsNode node) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void insertBefore(JsNode node) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public boolean isLvalue() {
+            return false;
+        }
+
+        @Override
+        public void removeMe() {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public void replaceMe(JsNode node) {
+            checkReplacement(this.node, node);
+            this.node = (T) node;
+        }
+
+        @Nullable
+        @Override
+        public JsNode getCurrentNode() {
+            return node;
+        }
+
+        protected T traverse(T node) {
+            this.node = node;
+            doTraverse(node, this);
+            return this.node;
+        }
+    }
+
+    protected static void checkReplacement(@SuppressWarnings("UnusedParameters") JsNode origNode, JsNode newNode) {
+        if (newNode == null) throw new RuntimeException("Cannot replace with null");
+    }
+
+    @Override
+    protected <T extends JsNode> T doAccept(T node) {
+        return new NodeContext<T>().traverse(node);
+    }
+
+    @Override
+    protected JsExpression doAcceptLvalue(JsExpression expr) {
+        return new LvalueContext().traverse(expr);
+    }
+
+    @Override
+    protected <T extends JsStatement> JsStatement doAcceptStatement(T statement) {
+        List<JsStatement> statements = new SmartList<JsStatement>(statement);
+        doAcceptStatementList(statements);
+
+        if (statements.size() == 1) {
+            return statements.get(0);
+        }
+
+        return new JsBlock(statements);
+    }
+
+    @Override
+    protected <T extends JsStatement> void doAcceptStatementList(List<T> statements) {
+        ListContext<T> context = new ListContext<T>();
+        statementContexts.push(context);
+        context.traverse(statements);
+        statementContexts.pop();
+    }
+
+    @Override
+    protected <T extends JsNode> void doAcceptList(List<T> collection) {
+        new ListContext<T>().traverse(collection);
+    }
+
+    @NotNull
+    protected JsContext getLastStatementLevelContext() {
+        return statementContexts.peek();
+    }
+
+    @Override
+    protected <T extends JsNode> void doTraverse(T node, JsContext ctx) {
+        node.traverse(this, ctx);
+    }
+
+}

js/js.dart-ast/src/com/google/dart/compiler/backend/js/ast/JsWhile.java

@@ -45,4 +45,13 @@ public class JsWhile extends SourceInfoAwareJsNode implements JsStatement {
         visitor.accept(condition);
         visitor.accept(body);
     }
+
+    @Override
+    public void traverse(JsVisitorWithContext v, JsContext ctx) {
+        if (v.visit(this, ctx)) {
+            condition = v.accept(condition);
+            body = v.acceptStatement(body);
+        }
+        v.endVisit(this, ctx);
+    }
 }