"import type" from TypeScript 3.8 not recognized

After upgrading to TypeScript 3.8.2 I also use the new “import type” feature https://www.typescriptlang.org/docs/handbook/modules.html#importing-types. Now I’m getting a warning from import/no-duplicates.

My affected code is e.g.:

import type { Options } from 'express-rate-limit';
import rateLimit from 'express-rate-limit';

[xiaoxiangmoe]

rule import/order also needs to consider import type and import

[kmui2]

Seems TypeScript ESLint currently (v2.22.0) does not have support for TypeScript 3.8 yet (>=3.2.1 <3.8.0, https://github.com/typescript-eslint/typescript-eslint/issues/1436). Because of this, it’s not currently possible to write a test for the import type syntax. So I’m afraid we need to wait for the TypeScript 3.8 support for ESLint.

For future reference, here’s the test I was writing:

context('TypeScript', function() {
  getNonDefaultParsers().forEach((parser) => {
    const parserConfig = {
      parser: parser,
      settings: {
        'import/parsers': { [parser]: ['.ts'] },
        'import/resolver': { 'eslint-import-resolver-typescript': true },
      },
    }

    ruleTester.run('no-duplicates', rule, {
      valid: [
        // #1667: ignore duplicate if is a typescript type import
        test(
          {
            code: "import type { x } from './foo'; import y from './foo'",
            parser,
          },
          parserConfig,
        ),
      ],
      invalid: [],
    })
  })
})

    "@typescript-eslint/parser": "^2.22.0",
    "eslint-import-resolver-typescript": "^2.0.0",
    "typescript": "^3.8.3",

As of these TypeScript ESLint package versions, it will produce the error:

AssertionError [ERR_ASSERTION] [ERR_ASSERTION]: A fatal parsing error occurred in autofix: Parsing error: '{' expected.