parcel 2 cannot build typescript project

Choose one: is this a 🐛 bug report or 🙋 feature request? bug report

🎛 Configuration (.babelrc, package.json, cli command)

 "targets": {
    "browser": {
      "main": "src/Main.ts",
      "publicUrl": "./"
    }
  }

🤔 Expected Behavior

build sucessfully

😯 Current Behavior

when i run parcel build src/Main.ts, it’ll run , but nothing show up, and the cpu usage is about 30%, even i have waited it for half hour, still same

💁 Possible Solution

not sure

🔦 Context

A Typescript H5 Game

💻 Code Sample

🌍 Your Environment

Software	Version(s)
Parcel	2.0.0-alpha.1.1
Node	12.9.1
npm/Yarn	6.11.2
Operating System	arch linux

[phaux]

The project builds when I simplify it by removing almost everything and rendering simple “hello world” with react + react-dom. It seems to be failing when it has to bundle material-ui

[mischnic]

import React from "react";
import { render } from "react-dom";
import { Button } from "@material-ui/core";

function App() {
	return <Button color="primary">Hello World</Button>;
}

render(<App />, document.getElementById("app"));

works correctly now.