Issue with typescript namespace

[ynifamily3]

Bug description

Here's an example you can reproduce.
https://github.com/ynifamily3/esbuild-loader-issue

index.ts

import { NS } from "./types";
import B = NS.A;

function x(a: B) {
  console.log(a.message);
}

x({ message: "Hello" });

types.ts

export namespace NS {
  export interface A {
    message: string;
  }
}

When trying to bundle, I see an error.
TypeError: Cannot read properties of undefined (reading 'A')

Reproduction

Clone this this repo
Run npm i
Run npm run build # using ts-loader
Run npm run start
You should see a working node app.
Run npm run build:esbuild # using esbuild-loader
Run npm run start
You should see an error.

Node.js package manager

npm

Environment

System:
    OS: Windows 10 10.0.19042
    CPU: (16) x64 11th Gen Intel(R) Core(TM) i7-11700 @ 2.50GHz
    Memory: 16.01 GB / 31.86 GB
  Binaries:
    Node: 16.13.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.22.17 - ~\AppData\Roaming\npm\yarn.CMD
    npm: 8.1.4 - C:\Program Files\nodejs\npm.CMD
  npmPackages:
    esbuild-loader: ^2.19.0 => 2.19.0
    webpack: ^5.74.0 => 5.74.0

Can you contribute a fix?

• I’m interested in opening a pull request for this issue.

[privatenumber]

Can you use:

import type { NS } from "./types";

[ynifamily3]

@privatenumber A ts(1380) error occurs. :(

[privatenumber]

I think this is the same issue as privatenumber/tsx#83

It's an esbuild issue so I'm closing this and redirecting conversation here:
evanw/esbuild#2468