com.google.javascript.jscomp.jsonml.NodeUtil.java Source code

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Here is the source code for com.google.javascript.jscomp.jsonml.NodeUtil.java

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/*
 * Copyright 2010 The Closure Compiler Authors.
 *
 * 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.javascript.jscomp.jsonml;

import com.google.common.base.Preconditions;
import com.google.javascript.rhino.Node;
import com.google.javascript.rhino.Token;

/**
 * Non public methods copied from com.google.javascript.jscomp.NodeUtil class.
 *
 * @author dhans@google.com (Daniel Hans)
 */
class NodeUtil {

    /**
     * @return Whether the node represents a FOR-IN loop.
     */
    static boolean isForIn(Node n) {
        return n.getType() == Token.FOR && n.getChildCount() == 3;
    }

    /**
     * @return Whether the node is used as a statement.
     */
    static boolean isStatement(Node n) {
        Node parent = n.getParent();
        // It is not possible to determine definitely if a node is a statement
        // or not if it is not part of the AST.  A FUNCTION node can be
        // either part of an expression or a statement.
        Preconditions.checkState(parent != null);
        switch (parent.getType()) {
        case Token.SCRIPT:
        case Token.BLOCK:
        case Token.LABEL:
            return true;
        default:
            return false;
        }
    }

    /**
     * Is this node a function declaration? A function declaration is a function
     * that has a name that is added to the current scope (i.e. a function that
     * is not part of a expression; see {@link #isFunctionExpression}).
     */
    static boolean isFunctionDeclaration(Node n) {
        return n.getType() == Token.FUNCTION && isStatement(n);
    }

    /**
     * Is this node a hoisted function declaration? A function declaration in the
     * scope root is hoisted to the top of the scope.
     * See {@link #isFunctionDeclaration}).
     */
    static boolean isHoistedFunctionDeclaration(Node n) {
        return isFunctionDeclaration(n) && (n.getParent().getType() == Token.SCRIPT
                || n.getParent().getParent().getType() == Token.FUNCTION);
    }
}