[Bug]: Destructurisation transformation loses typescript types

[cainrus]

💻

• Would you like to work on a fix?

How are you using Babel?

@babel/cli

Input code

type Point = {
  x: number;
  y: number;
}

export function test({x, y}: Point) {
  return x * y;
}

Configuration file name

.babelrc.json

Configuration

{
  "plugins": [
    "@babel/plugin-transform-parameters",
    ["@babel/plugin-transform-destructuring", {
      "loose": true
    }],
    "@babel/plugin-syntax-typescript"
  ]
}

Current and expected behavior

Current output:

type Point = {
  x: number;
  y: number;
};
export function test(_ref) {
  let x = _ref.x,
      y = _ref.y;
  return x * y;
}

Expected output:

type Point = {
  x: number;
  y: number;
};
export function test(_ref: Point) {
  let x = _ref.x,
      y = _ref.y;
  return x * y;
}

Environment

System:
OS: macOS 12.2
Binaries:
Node: 16.14.2 - ~/.nvm/versions/node/v16.14.2/bin/node
Yarn: 3.2.1 - /usr/local/bin/yarn
npm: 8.5.0 - ~/.nvm/versions/node/v16.14.2/bin/npm
npmPackages:
@babel/cli: ^7.17.10 => 7.17.10
@babel/core: ^7.18.5 => 7.18.5
@babel/plugin-syntax-typescript: ^7.17.12 => 7.17.12
@babel/plugin-transform-destructuring: ^7.18.0 => 7.18.0

Possible solution

No response

Additional context

Reproduction repo

[babel-bot]

Hey @cainrus! We really appreciate you taking the time to report an issue. The collaborators on this project attempt to help as many people as possible, but we're a limited number of volunteers, so it's possible this won't be addressed swiftly.

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[nicolo-ribaudo]

Out of curiosity, which tool/platform are you using that supports TS but not destructuring?

[cainrus]

Out of curiosity, which tool/platform are you using that supports TS but not destructuring?

I want to use it with assemblyscript, to downgrade some neat modern syntax features to compatible with assemblyscript syntax (partial es2015 support)

[magic-akari]

Is this the only case which type is losing?
I am willing to fix it, and I guess there are a lot of similar issues.

[cainrus]

I guess there are a lot of similar issues.

Definitely a lot. I saw some more cases within my experiments (regenerated loops?)
But destruction helps a lot with boilerplate code.