How to avoid generating a .d.ts when it is already existed? I think it should copy the original .d.ts file

[lz1998]

I have a TypeScript project. Most of the code is written in TS, but there is a file generated by protobufjs called proto.js. And there is a generated proto.d.ts.
When I execute tsc, it doesn't copy the original proto.d.tsto lib directory, but generate another proto.d.ts.

Project: https://github.com/ProtobufBot/js-pbbot

src/proto/proto.d.ts

import * as $protobuf from "protobufjs";
/** Namespace onebot. */
export namespace onebot {

    /** Properties of a Frame. */
    interface IFrame {

        /** Frame botId */
        botId?: (Long|null);

......

Run tsc --build tsconfig.json

lib/proto/proto.d.ts

export = $root;
declare var $root: $protobuf.Root;
import $protobuf = require("protobufjs/minimal");

I think it should copy the original .d.ts file when .d.ts file is existed, but it doesn't.

[cspotcode]

This is a tsc question, not a ts-node question, so I'm going to close it as off-topic.

[lz1998]

Which repo should I create this issue?