Different Declaration output for same code from js and ts file

This is a test project to demonstrate a bug in the TypeScript compiler when using JavaScript. See microsoft/TypeScript#51622

Outline

When creating types from a ts source file it keeps the import pathes as is. (which is expected)

import { LitElement } from "lit";
export class ElementA extends LitElement {}

import { LitElement } from "lit";
export declare class ElementA extends LitElement {}

When creating types from "the exact same file" but as a js it changes the import pathes by "resolving" them.

import { LitElement } from "lit";
export class ElementB extends LitElement {}

export class ElementB extends LitElement {}
import { LitElement } from "lit-element/lit-element.js";

export class ElementB extends LitElement {}
import { LitElement } from "lit";

Because of the miss match between the "location" of LitElement TS believes those are different LitElement types.