AST反混淆进阶-try-catch-finally简化

实现目的：try-catch-finally简化,删除catch部分，其他顺序排列，减少无用代码，增强可读性

处理前 demo.js

try {
	a = 1;
	b = 2;
} catch (_0x2aff1a) {
	c = 3;
	d = 4;
} finally {
	e = 5;
	f = 6;
}

处理后 demoNew.js

a = 1;
b = 2;
e = 5;
f = 6;

主逻辑源码 ObDecryFuMain.js

const fs = require("fs");//文件读写
const parse = require("@babel/parser"); //解析为ast
const traverse = require('@babel/traverse').default;//遍历节点
const t = require('@babel/types');//类型
const generator = require('@babel/generator').default;//ast解析为代码


//读取js文件
const jscode = fs.readFileSync(
    './demo.js', {
        encoding: 'utf-8'
    }
);
let ast = parse.parse(jscode);//js转ast

function del_TryStatement(path) {
	// try-catch-finally 语句简化
	if (path.node.block) {//
		if (path.node.finalizer) {
			//获取try中的body长度
			blocklength = path.node.block.body.length;
			//获取finally中的body长度
			finalizerlength = path.node.finalizer.body.length;
			//遍历finally中的内容，添加
			for (var i = 0; i < finalizerlength; i++) {
				path.node.block.body[blocklength + i] = path.node.finalizer.body[i];
			}
			//节点替换
			path.replaceInline(path.node.block.body);
		} else {
			path.replaceInline(path.node.block.body);
		}


	}
}
traverse(ast, {TryStatement: {exit: [del_TryStatement]},});
let {code} = generator(ast,opts = {jsescOption:{"minimal":true}})
//文件保存
fs.writeFile('./demoNew.js', code, (err) => {
});