CompoundAssignmentExpression.java

/**
 *  Copyright 2013 Douglas Campos, and individual contributors
 *
 *  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 org.dynjs.parser.ast;

import java.util.ArrayList;
import java.util.List;

import org.dynjs.exception.ThrowException;
import org.dynjs.parser.CodeVisitor;
import org.dynjs.parser.js.Position;
import org.dynjs.runtime.EnvironmentRecord;
import org.dynjs.runtime.ExecutionContext;
import org.dynjs.runtime.Reference;

public class CompoundAssignmentExpression extends AbstractExpression {

    private final AbstractBinaryExpression rootExpr;

    public CompoundAssignmentExpression(AbstractBinaryExpression rootExpr) {
        this.rootExpr = rootExpr;
    }
    
    public Position getPosition() {
        return this.rootExpr.getPosition();
    }
    
    public List<FunctionDeclaration> getFunctionDeclarations() {
        return this.rootExpr.getFunctionDeclarations();
    }

    @Override
    public Object interpret(ExecutionContext context, boolean debug) {
        Object r = getRootExpr().interpret(context, debug);
        Object lref = getRootExpr().getLhs().interpret(context, debug);

        if (lref instanceof Reference) {
            if (((Reference) lref).isStrictReference()) {
                if (((Reference) lref).getBase() instanceof EnvironmentRecord) {
                    if (((Reference) lref).getReferencedName().equals("arguments") || ((Reference) lref).getReferencedName().equals("eval")) {
                        throw new ThrowException(context, context.createSyntaxError("invalid assignment: " + ((Reference) lref).getReferencedName()));
                    }
                }
            }

            ((Reference) lref).putValue(context, r);
            return(r);

        }

        throw new ThrowException(context, context.createReferenceError("cannot assign to non-reference"));
    }

    public AbstractBinaryExpression getRootExpr() {
        return this.rootExpr;
    }

    public String toString() {
        return rootExpr.getLhs() + " " + rootExpr.getOp() + "=" + rootExpr.getRhs();
    }
    
    public int getSizeMetric() {
        return this.rootExpr.getSizeMetric() + 5;
    }

    @Override
    public Object accept(Object context, CodeVisitor visitor, boolean strict) {
        return visitor.visit( context, this, strict);
    }

    public String dump(String indent) {
        StringBuilder buf = new StringBuilder(super.dump(indent));

        buf.append(rootExpr.dump(indent + "  "));

        return buf.toString();
    }
}