problem with try catch on ie8

描述

nodejs@8.1.1
babel-core@6.25.0
babel-preset-babili@0.1.4
babel-preset-env@1.5.2

var babel = require('babel-core');
var env = require('babel-preset-env');
var babili = require('babel-preset-babili');
var t = babel.transformFileSync('code.js', {
	presets: [[env,{"targets":{"browsers":"ie >= 7"}}],babili],
	babelrc: false
});
console.log(t.code);

function a(b){
	try{
		console.log(123);
	} catch(e){}
	b();
}
a(function(){
	console.log(456);
});

node test.js

"use strict";function a(a){try{console.log(123)}catch(a){}a()}a(function(){console.log(456)});

貢獻者指南

技術棧

javascriptnodejs

領域

build system

議題類型

bug

難度面向新貢獻者的預計實作難度，1 表示很小改動，5 表示專家級工作。

3

預計時間有經驗貢獻者完成調查、實作、測試並準備 pull request 的粗略時間範圍。

1-3 hours

活動狀態議題目前的可參與程度：新鮮、活躍、陳舊、阻塞或等待維護者輸入。

stale

清晰度議題是否清楚說明預期改動、驗收標準和下一步。

clear

前置要求

JavaScriptBabel basics

新手友善度1-100 的估計分數，表示該議題對首次貢獻者的友善程度。

20

研究方向

The issue arises when babili minifies a try catch block where the catch variable 'e' gets renamed to 'a', conflicting with the function parameter 'a'. This causes IE8 to throw a syntax error because catch parameter names cannot shadow function parameter names in older IE. To fix, investigate how babili handles catch parameter renaming and ensure it avoids such conflicts, possibly by preserving the original name or using a different renaming strategy for catch parameters. The relevant code is in babili's variable renaming logic, likely in the scope handling of try catch blocks.