com.google.javascript.jscomp.NameAnonymousFunctions Maven / Gradle / Ivy
/*
* Copyright 2004 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;
import com.google.javascript.rhino.Node;
import java.util.logging.Logger;
/**
* Gives anonymous function names. This makes it way easier to debug because
* debuggers and stack traces use the function names. So if you have
*
* goog.string.htmlEscape = function(str) {
* }
*
* It will become
*
* goog.string.htmlEscape = function $goog$string$htmlEscape$(str) {
* }
*
*/
class NameAnonymousFunctions implements CompilerPass {
private static final Logger logger = Logger.getLogger(
NameAnonymousFunctions.class.getName());
static final char DELIMITER = '$';
private final AbstractCompiler compiler;
private int namedCount = 0;
private int bytesUsed = 0;
NameAnonymousFunctions(AbstractCompiler compiler) {
this.compiler = compiler;
}
@Override
public void process(Node externs, Node root) {
AnonymousFunctionNamingCallback namingCallback =
new AnonymousFunctionNamingCallback(new AnonymousFunctionNamer());
NodeTraversal.traverse(compiler, root, namingCallback);
logger.fine("Named " + namedCount + " anon functions using " +
bytesUsed + " bytes");
}
/**
* Names anonymous functions. The function names don't have to be globally
* unique or even locally unique. We make them somewhat unique because of a
* bug in IE (and there may be other bugs we haven't found). See unit test for
* more info.
*/
private class AnonymousFunctionNamer
implements AnonymousFunctionNamingCallback.FunctionNamer {
private final NodeNameExtractor nameExtractor;
AnonymousFunctionNamer() {
this.nameExtractor = new NodeNameExtractor(DELIMITER);
}
/**
* Returns a likely not conflicting name to make IE happy. See unit test
* for more info.
*/
private String getLikelyNonConflictingName(String name) {
return DELIMITER + name + DELIMITER;
}
@Override
public final String getName(Node node) {
return nameExtractor.getName(node);
}
@Override
public final void setFunctionName(String name, Node fnNode) {
Node fnNameNode = fnNode.getFirstChild();
String uniqueName = getLikelyNonConflictingName(name);
fnNameNode.setString(uniqueName);
compiler.reportChangeToEnclosingScope(fnNameNode);
namedCount++;
bytesUsed += uniqueName.length();
}
@Override
public final String getCombinedName(String lhs, String rhs) {
return lhs + DELIMITER + rhs;
}
}
}