我正在尝试使用解析器(通过uglify-js,但其他任何方法都很好),以便从输入字符串中提取私有函数。
a.js
var UglifyJS = require('uglify-js');
var ast = UglifyJS.parse(require('fs').readFileSync('b.js').toString());
var stream = UglifyJS.OutputStream({});
// need to manipulate ast here to extract the `sum` function
ast.print(stream)
console.log(stream+'')
b.js
var addRandom = (function() {
function sum(x, y) {
return x + y
};
return function (input) {
return sum(input, Math.random());
};
})();
运行node a.js
会产生......
var fn=function(){function sum(x,y){return x+y}function addRandom(input){return sum(input,Math.random())}return{addRandom:addRandom}}();
...但我需要在输出之前操纵ast,以提取sum
函数。我要打印的是......
function sum(x,y){return x+y}
如何在输出之前提取我想要的AST树的一部分?
答案 0 :(得分:1)
使用TreeWalker可以管理...
a.js
var UglifyJS = require('uglify-js'),
fs = require('fs');
function showPrivates(file) {
var privates = {};
UglifyJS.parse(fs.readFileSync(file).toString('UTF-8')).walk(new UglifyJS.TreeWalker(function(node) {
if (node instanceof UglifyJS.AST_Defun) {
var stream = UglifyJS.OutputStream({});
node.print(stream);
privates[node.name.name] = stream.toString('UTF-8');
}
}));
return privates;
}
console.log(showPrivates('b.js').sum);
b.js
var addRandom = (function() {
function sum(x, y) {
return x + y;
};
function random(x) {
return Math.floor(Math.random()*x);
};
return function (input) {
return sum(input, random(10));
};
})();
......看看......
console.log(showPrivates('b.js').sum);
// function sum(x,y){return x+y}
答案 1 :(得分:1)
var UglifyJS = require('uglify-js');
var code = require('fs').readFileSync('b.js').toString();
var stream = UglifyJS.OutputStream({});
var toplevel = UglifyJS.parse(code);
var walker = new UglifyJS.TreeWalker(function(node){
if (node instanceof UglifyJS.AST_Defun) {
node.print(stream);
}
});
toplevel.walk(walker);
console.log(stream + '');