// Copyright (C) 2005 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.caja.parser.js;
import com.google.caja.lexer.FilePosition;
import com.google.caja.lexer.TokenConsumer;
import com.google.caja.parser.ParseTreeNode;
import com.google.caja.reporting.RenderContext;
import java.util.List;
/**
* Introduces a variable into the current scope.
*
* @author mikesamuel@gmail.com
*/
public class Declaration extends AbstractStatement {
private static final long serialVersionUID = 8412211687133669346L;
// Local member variables are only changed in childrenChanged(),
// so this class satisfies the immutability contract of the superclass.
private Identifier identifier;
private Expression initializer;
/** @param value unused. This ctor is provided for reflection. */
@ReflectiveCtor
public Declaration(
FilePosition pos, Void value, List<? extends ParseTreeNode> children) {
super(pos, ParseTreeNode.class);
createMutation().appendChildren(children).execute();
}
public Declaration(
FilePosition pos, Identifier identifier, Expression initializer) {
super(pos, ParseTreeNode.class);
Mutation m = createMutation();
m.appendChild(identifier);
if (null != initializer) { m.appendChild(initializer); }
m.execute();
}
@Override
protected void childrenChanged() {
super.childrenChanged();
List<? extends ParseTreeNode> children = children();
this.identifier = (Identifier) children.get(0);
if (this.identifier.getName() == null) {
throw new NullPointerException();
}
this.initializer = (children.size() > 1
? (Expression) children.get(1)
: null);
if (children.size() > 2) {
throw new IllegalArgumentException(
"Declaration has extraneous children "
+ children.subList(2, children.size()));
}
}
public Identifier getIdentifier() { return this.identifier; }
public String getIdentifierName() { return this.identifier.getName(); }
public Expression getInitializer() { return this.initializer; }
@Override
public Object getValue() { return null; }
public void render(RenderContext rc) {
TokenConsumer out = rc.getOut();
out.mark(getFilePosition());
out.consume("var");
renderShort(rc);
}
/**
* Renders the short form without the "var" keyword.
* This is used in multi declarations, such as in
* {@code for (var a = 0, b = 1, ...)}.
*/
void renderShort(RenderContext rc) {
TokenConsumer out = rc.getOut();
out.mark(getFilePosition());
if (identifier.getName() == null) {
throw new IllegalStateException(
"null name for declaration at " + getFilePosition());
}
identifier.render(rc);
if (null != initializer) {
out.consume("=");
boolean isComma = Operation.is(initializer, Operator.COMMA);
if (isComma) { out.consume("("); }
initializer.render(rc);
if (isComma) { out.consume(")"); }
}
}
public boolean hasHangingConditional() { return false; }
}