@typescript-eslint/no-unused-var error in namespace

.eslintrc.js

'use strict'

module.exports = {
  root: true,
  extends: ['plugin:@typescript-eslint/recommended'],
  rules: {
    '@typescript-eslint/no-unused-vars': 'error',
  },
}

.gitignore

node_modules
package-lock.json

README.md

overview

npm run lint

• @typescript-eslint/[email protected] - no errors
• @typescript-eslint/[email protected] - error
• @typescript-eslint/[email protected] - error

expected

No errors

actual

If a function parameter matches the function name, the function name is marked as "unused"

// types.d.ts
declare namespace Foo {
    function foo(foo: string): void // 'foo' is defined but never used.
}

package.json

{
  "name": "unused-function-param",
  "private": true,
  "version": "1.0.0",
  "description": "",
  "scripts": {
    "lint": "eslint '**/*.ts'"
  },
  "keywords": [],
  "author": "Mike Cousins <[email protected]> (https://mike.cousins.io)",
  "license": "MIT",
  "devDependencies": {
    "@typescript-eslint/eslint-plugin": "1.4.1",
    "eslint": "5.14.1",
    "typescript": "3.3.3333"
  }
}

types.d.ts

declare namespace Foo {
    function foo(foo: string): void
}