Untitled

/src
   /test
      unittest.ts
      unittest.html
    main.ts

class Point {
    constructor(public x: number, public y: number) {
    }
}
export { Point };

import Point from "../main";

function basicTest() {
   let Point = new Point(10, 15);
   // ...
}

basicTest();

<html>
  <meta charset="UTF-8">
  <head></head>
  <body>
    <script src="unittest.js" charset="utf-8"></script>
  </body>
</html>