Adding ignores to the typescript-eslint recommended configuration?

Question

I'm trying to add an ignores object to the typescript-eslint configuration

I figured this would do the trick:

import eslint from "@eslint/js";
import tseslint from "typescript-eslint";

export default tseslint.config(
  eslint.configs.recommended,
  ...tseslint.configs.recommended,
).push({
  ignores: ["build/*"]
});

However when running npx eslint . it produces this error:

Oops! Something went wrong! :(

ESLint: 8.57.0

TypeError: All arguments must be objects.
    at ObjectSchema.merge (/Users/oleersoy/Github/fs-typescript-starter/node_modules/@humanwhocodes/object-schema/src/object-schema.js:234:19)
    at /Users/oleersoy/Github/fs-typescript-starter/node_modules/@humanwhocodes/config-array/api.js:935:42
    at Array.reduce (<anonymous>)
    at FlatConfigArray.getConfig (/Users/oleersoy/Github/fs-typescript-starter/node_modules/@humanwhocodes/config-array/api.js:934:39)
    at FlatConfigArray.isFileIgnored (/Users/oleersoy/Github/fs-typescript-starter/node_modules/@humanwhocodes/config-array/api.js:962:15)
    at /Users/oleersoy/Github/fs-typescript-starter/node_modules/eslint/lib/eslint/eslint-helpers.js:312:49
    at Array.reduce (<anonymous>)
    at entryFilter (/Users/oleersoy/Github/fs-typescript-starter/node_modules/eslint/lib/eslint/eslint-helpers.js:299:28)
    at Object.isAppliedFilter (/Users/oleersoy/Github/fs-typescript-starter/node_modules/@nodelib/fs.walk/out/readers/common.js:12:31)
    at AsyncReader._handleEntry (/Users/oleersoy/Github/fs-typescript-starter/node_modules/@nodelib/fs.walk/out/readers/async.js:86:20)

How should we go about extending the configuration to add ignores?

Answer 1

config expects objects; push acts on arrays. Just add the additional rule object:

import eslint from "@eslint/js";
import tseslint from "typescript-eslint";

export default tseslint.config(
  eslint.configs.recommended,
  ...tseslint.configs.recommended,
  {
    ignores: ["build/*"]
  }
);

See here for the documentation.