@Override
  public void process(Node externs, Node root) {
    Node initCode = null;
    if (!initCodeSource.isEmpty()) {
      Node initCodeRoot = compiler.parseSyntheticCode("template:init", initCodeSource);
      if (initCodeRoot != null && initCodeRoot.getFirstChild() != null) {
        initCode = initCodeRoot.removeChildren();
      } else {
        return; // parse failure
      }
    }

    NodeTraversal.traverseEs6(compiler, root, new RemoveCallback(declarationsToRemove));
    NodeTraversal.traverseEs6(compiler, root, new InstrumentCallback());

    if (!appNameSetter.isEmpty()) {
      Node call = IR.call(IR.name(appNameSetter), IR.string(appNameStr));
      call.putBooleanProp(Node.FREE_CALL, true);
      Node expr = IR.exprResult(call);

      Node addingRoot = compiler.getNodeForCodeInsertion(null);
      addingRoot.addChildrenToFront(expr.useSourceInfoIfMissingFromForTree(addingRoot));
      compiler.reportCodeChange();
    }

    if (initCode != null) {
      Node addingRoot = compiler.getNodeForCodeInsertion(null);
      addingRoot.addChildrenToFront(initCode);
      compiler.reportCodeChange();
    }
  }
  /**
   * Adds an interface for the given ClassDefinition to externs. This allows generated setter
   * functions for read-only properties to avoid renaming altogether.
   *
   * @see https://www.polymer-project.org/0.8/docs/devguide/properties.html#read-only
   */
  private void addInterfaceExterns(
      final ClassDefinition cls, List<MemberDefinition> readOnlyProps) {
    Node block = IR.block();

    String interfaceName = getInterfaceName(cls);
    Node fnNode = IR.function(IR.name(""), IR.paramList(), IR.block());
    Node varNode = IR.var(NodeUtil.newQName(compiler, interfaceName), fnNode);

    JSDocInfoBuilder info = new JSDocInfoBuilder(true);
    info.recordInterface();
    varNode.setJSDocInfo(info.build());
    block.addChildToBack(varNode);

    appendPropertiesToBlock(cls, block, interfaceName + ".prototype.");
    for (MemberDefinition prop : readOnlyProps) {
      // Add all _set* functions to avoid renaming.
      String propName = prop.name.getString();
      String setterName = "_set" + propName.substring(0, 1).toUpperCase() + propName.substring(1);
      Node setterExprNode =
          IR.exprResult(NodeUtil.newQName(compiler, interfaceName + ".prototype." + setterName));

      JSDocInfoBuilder setterInfo = new JSDocInfoBuilder(true);
      JSTypeExpression propType = getTypeFromProperty(prop);
      setterInfo.recordParameter(propName, propType);
      setterExprNode.getFirstChild().setJSDocInfo(setterInfo.build());

      block.addChildToBack(setterExprNode);
    }

    Node parent = polymerElementExterns.getParent();
    Node stmts = block.removeChildren();
    parent.addChildrenToBack(stmts);

    compiler.reportCodeChange();
  }
  /**
   * Duplicates the PolymerElement externs with a different element base class if needed. For
   * example, if the base class is HTMLInputElement, then a class PolymerInputElement will be added.
   * If the element does not extend a native HTML element, this method is a no-op.
   */
  private void appendPolymerElementExterns(final ClassDefinition cls) {
    if (!nativeExternsAdded.add(cls.nativeBaseElement)) {
      return;
    }

    Node block = IR.block();

    Node baseExterns = polymerElementExterns.cloneTree();
    String polymerElementType = getPolymerElementType(cls);
    baseExterns.getFirstChild().setString(polymerElementType);

    String elementType = tagNameMap.get(cls.nativeBaseElement);
    JSTypeExpression elementBaseType =
        new JSTypeExpression(new Node(Token.BANG, IR.string(elementType)), VIRTUAL_FILE);
    JSDocInfoBuilder baseDocs = JSDocInfoBuilder.copyFrom(baseExterns.getJSDocInfo());
    baseDocs.changeBaseType(elementBaseType);
    baseExterns.setJSDocInfo(baseDocs.build());
    block.addChildToBack(baseExterns);

    for (Node baseProp : polymerElementProps) {
      Node newProp = baseProp.cloneTree();
      Node newPropRootName =
          NodeUtil.getRootOfQualifiedName(newProp.getFirstChild().getFirstChild());
      newPropRootName.setString(polymerElementType);
      block.addChildToBack(newProp);
    }

    Node parent = polymerElementExterns.getParent();
    Node stmts = block.removeChildren();
    parent.addChildrenAfter(stmts, polymerElementExterns);

    compiler.reportCodeChange();
  }
  public void process(Node externs, Node root) {
    Node initCode = null;
    if (initCodeSource.length() != 0) {
      Node initCodeRoot = compiler.parseSyntheticCode(templateFilename + ":init", initCodeSource);
      if (initCodeRoot != null && initCodeRoot.getFirstChild() != null) {
        initCode = initCodeRoot.removeChildren();
      } else {
        return; // parse failure
      }
    }

    NodeTraversal.traverse(compiler, root, new RemoveCallback(declarationsToRemove));
    NodeTraversal.traverse(compiler, root, new InstrumentCallback());

    if (appNameSetter.length() != 0) {
      Node call =
          new Node(
              Token.CALL, Node.newString(Token.NAME, appNameSetter), Node.newString(appNameStr));
      Node expr = new Node(Token.EXPR_RESULT, call);

      Node addingRoot = compiler.getNodeForCodeInsertion(null);
      addingRoot.addChildrenToFront(expr);
      compiler.reportCodeChange();
    }

    if (initCode != null) {
      Node addingRoot = compiler.getNodeForCodeInsertion(null);
      addingRoot.addChildrenToFront(initCode);
      compiler.reportCodeChange();
    }
  }
 void replaceNodeInPlace(Node n, Node replacement) {
   Node parent = n.getParent();
   if (n.hasChildren()) {
     Node children = n.removeChildren();
     replacement.addChildrenToFront(children);
   }
   parent.replaceChild(n, replacement);
 }
  private void rewriteGoogDefineClass(Node exprRoot, final ClassDefinition cls) {
    // For simplicity add everything into a block, before adding it to the AST.
    Node block = IR.block();

    // remove the original jsdoc info if it was attached to the value.
    cls.constructor.value.setJSDocInfo(null);
    if (exprRoot.isVar()) {
      // example: var ctr = function(){}
      Node var = IR.var(cls.name.cloneTree(), cls.constructor.value).srcref(exprRoot);
      JSDocInfo mergedClassInfo = mergeJsDocFor(cls, var);
      var.setJSDocInfo(mergedClassInfo);
      block.addChildToBack(var);
    } else {
      // example: ns.ctr = function(){}
      Node assign =
          IR.assign(cls.name.cloneTree(), cls.constructor.value)
              .srcref(exprRoot)
              .setJSDocInfo(cls.constructor.info);

      JSDocInfo mergedClassInfo = mergeJsDocFor(cls, assign);
      assign.setJSDocInfo(mergedClassInfo);

      Node expr = IR.exprResult(assign).srcref(exprRoot);
      block.addChildToBack(expr);
    }

    if (cls.superClass != null) {
      // example: goog.inherits(ctr, superClass)
      block.addChildToBack(
          fixupSrcref(
              IR.exprResult(
                  IR.call(
                          NodeUtil.newQName(compiler, "goog.inherits").srcrefTree(cls.superClass),
                          cls.name.cloneTree(),
                          cls.superClass.cloneTree())
                      .srcref(cls.superClass))));
    }

    for (MemberDefinition def : cls.staticProps) {
      // remove the original jsdoc info if it was attached to the value.
      def.value.setJSDocInfo(null);

      // example: ctr.prop = value
      block.addChildToBack(
          fixupSrcref(
              IR.exprResult(
                  fixupSrcref(
                          IR.assign(
                              IR.getprop(
                                      cls.name.cloneTree(),
                                      IR.string(def.name.getString()).srcref(def.name))
                                  .srcref(def.name),
                              def.value))
                      .setJSDocInfo(def.info))));
      // Handle inner class definitions.
      maybeRewriteClassDefinition(block.getLastChild());
    }

    for (MemberDefinition def : cls.props) {
      // remove the original jsdoc info if it was attached to the value.
      def.value.setJSDocInfo(null);

      // example: ctr.prototype.prop = value
      block.addChildToBack(
          fixupSrcref(
              IR.exprResult(
                  fixupSrcref(
                          IR.assign(
                              IR.getprop(
                                      fixupSrcref(
                                          IR.getprop(
                                              cls.name.cloneTree(),
                                              IR.string("prototype").srcref(def.name))),
                                      IR.string(def.name.getString()).srcref(def.name))
                                  .srcref(def.name),
                              def.value))
                      .setJSDocInfo(def.info))));
      // Handle inner class definitions.
      maybeRewriteClassDefinition(block.getLastChild());
    }

    if (cls.classModifier != null) {
      // Inside the modifier function, replace references to the argument
      // with the class name.
      //   function(cls) { cls.Foo = bar; }
      // becomes
      //   function(cls) { theClassName.Foo = bar; }
      // The cls parameter is unused, but leave it there so that it
      // matches the JsDoc.
      // TODO(tbreisacher): Add a warning if the param is shadowed or reassigned.
      Node argList = cls.classModifier.getFirstChild().getNext();
      Node arg = argList.getFirstChild();
      final String argName = arg.getString();
      NodeTraversal.traverse(
          compiler,
          cls.classModifier.getLastChild(),
          new AbstractPostOrderCallback() {
            @Override
            public void visit(NodeTraversal t, Node n, Node parent) {
              if (n.isName() && n.getString().equals(argName)) {
                parent.replaceChild(n, cls.name.cloneTree());
              }
            }
          });

      block.addChildToBack(
          IR.exprResult(
                  fixupFreeCall(
                      IR.call(cls.classModifier, cls.name.cloneTree()).srcref(cls.classModifier)))
              .srcref(cls.classModifier));
    }

    Node parent = exprRoot.getParent();
    Node stmts = block.removeChildren();
    parent.addChildrenAfter(stmts, exprRoot);
    parent.removeChild(exprRoot);

    compiler.reportCodeChange();
  }
  private void rewritePolymerClass(Node exprRoot, final ClassDefinition cls, NodeTraversal t) {
    // Add {@code @lends} to the object literal.
    Node call = exprRoot.getFirstChild();
    if (call.isAssign()) {
      call = call.getChildAtIndex(1);
    } else if (call.isName()) {
      call = call.getFirstChild();
    }

    Node objLit = cls.descriptor;
    if (hasShorthandAssignment(objLit)) {
      compiler.report(JSError.make(objLit, POLYMER_SHORTHAND_NOT_SUPPORTED));
      return;
    }

    JSDocInfoBuilder objLitDoc = new JSDocInfoBuilder(true);
    objLitDoc.recordLends(cls.target.getQualifiedName() + ".prototype");
    objLit.setJSDocInfo(objLitDoc.build());

    this.addTypesToFunctions(objLit, cls.target.getQualifiedName());
    this.switchDollarSignPropsToBrackets(objLit);
    this.quoteListenerAndHostAttributeKeys(objLit);

    // For simplicity add everything into a block, before adding it to the AST.
    Node block = IR.block();

    if (cls.nativeBaseElement != null) {
      this.appendPolymerElementExterns(cls);
    }
    JSDocInfoBuilder constructorDoc = this.getConstructorDoc(cls);

    // Remove the original constructor JS docs from the objlit.
    Node ctorKey = cls.constructor.value.getParent();
    if (ctorKey != null) {
      ctorKey.removeProp(Node.JSDOC_INFO_PROP);
    }

    if (cls.target.isGetProp()) {
      // foo.bar = Polymer({...});
      Node assign = IR.assign(cls.target.cloneTree(), cls.constructor.value.cloneTree());
      assign.setJSDocInfo(constructorDoc.build());
      Node exprResult = IR.exprResult(assign);
      block.addChildToBack(exprResult);
    } else {
      // var foo = Polymer({...}); OR Polymer({...});
      Node var = IR.var(cls.target.cloneTree(), cls.constructor.value.cloneTree());
      var.setJSDocInfo(constructorDoc.build());
      block.addChildToBack(var);
    }

    appendPropertiesToBlock(cls, block, cls.target.getQualifiedName() + ".prototype.");
    appendBehaviorMembersToBlock(cls, block);
    List<MemberDefinition> readOnlyProps = parseReadOnlyProperties(cls, block);
    addInterfaceExterns(cls, readOnlyProps);
    removePropertyDocs(objLit);

    block.useSourceInfoIfMissingFromForTree(exprRoot);
    Node stmts = block.removeChildren();
    Node parent = exprRoot.getParent();

    // If the call to Polymer() is not in the global scope and the assignment target is not
    // namespaced (which likely means it's exported to the global scope), put the type declaration
    // into the global scope at the start of the current script.
    //
    // This avoids unknown type warnings which are a result of the compiler's poor understanding of
    // types declared inside IIFEs or any non-global scope. We should revisit this decision after
    // moving to the new type inference system which should be able to infer these types better.
    if (!t.getScope().isGlobal() && !cls.target.isGetProp()) {
      Node scriptNode = NodeUtil.getEnclosingScript(exprRoot);
      scriptNode.addChildrenToFront(stmts);
    } else {
      Node beforeRoot = parent.getChildBefore(exprRoot);
      if (beforeRoot == null) {
        parent.addChildrenToFront(stmts);
      } else {
        parent.addChildrenAfter(stmts, beforeRoot);
      }
    }

    if (exprRoot.isVar()) {
      Node assignExpr = varToAssign(exprRoot);
      parent.replaceChild(exprRoot, assignExpr);
    }

    compiler.reportCodeChange();
  }
  private void visitSuper(Node node, Node parent) {
    Node enclosing = parent;
    Node potentialCallee = node;
    if (!parent.isCall()) {
      enclosing = parent.getParent();
      potentialCallee = parent;
    }
    if (!enclosing.isCall() || enclosing.getFirstChild() != potentialCallee) {
      cannotConvertYet(node, "Only calls to super or to a method of super are supported.");
      return;
    }
    Node clazz = NodeUtil.getEnclosingClass(node);
    if (clazz == null) {
      compiler.report(JSError.make(node, NO_SUPERTYPE));
      return;
    }
    if (NodeUtil.getClassNameNode(clazz) == null) {
      // Unnamed classes of the form:
      //   f(class extends D { ... });
      // give the problem that there is no name to be used in the call to goog.base for the
      // translation of super calls.
      // This will throw an error when the class is processed.
      return;
    }

    Node enclosingMemberDef = NodeUtil.getEnclosingClassMember(node);
    if (enclosingMemberDef.isStaticMember()) {
      Node superName = clazz.getFirstChild().getNext();
      if (!superName.isQualifiedName()) {
        // This has already been reported, just don't need to continue processing the class.
        return;
      }
      Node callTarget;
      potentialCallee.detachFromParent();
      if (potentialCallee == node) {
        // of the form super()
        potentialCallee =
            IR.getprop(superName.cloneTree(), IR.string(enclosingMemberDef.getString()));
        enclosing.putBooleanProp(Node.FREE_CALL, false);
      } else {
        // of the form super.method()
        potentialCallee.replaceChild(node, superName.cloneTree());
      }
      callTarget = IR.getprop(potentialCallee, IR.string("call"));
      enclosing.addChildToFront(callTarget);
      enclosing.addChildAfter(IR.thisNode(), callTarget);
      enclosing.useSourceInfoIfMissingFromForTree(enclosing);
      compiler.reportCodeChange();
      return;
    }

    String methodName;
    Node callName = enclosing.removeFirstChild();
    if (callName.isSuper()) {
      methodName = enclosingMemberDef.getString();
    } else {
      methodName = callName.getLastChild().getString();
    }
    Node baseCall =
        baseCall(clazz, methodName, enclosing.removeChildren())
            .useSourceInfoIfMissingFromForTree(enclosing);
    enclosing.getParent().replaceChild(enclosing, baseCall);
    compiler.reportCodeChange();
  }