];

In the eslintrc config system it was possible to use`eslint-env` configuration comments to define globals for a file.

These comments are no longer recognized when linting with flat config: in a future version of ESLint,`eslint-env` comments will be reported as errors.

For this reason, when migrating from eslintrc to flat config,`eslint-env` configuration comments should be removed from all files.

They can be either replaced with equivalent but more verbose`global` configuration comments, or dropped in favor of`globals` definitions in the config file.

For example, when using eslintrc, a file to be linted could look like this:

describe("unit tests", ()=> {

it("should pass", ()=> {

});

});

In the above example,`describe` and`it` would be recognized as global identifiers because of the`/* eslint-env mocha */` comment.

The same effect can be achieved with flat config with a`global` configuration comment, e.g.:

describe("unit tests", ()=> {

it("should pass", ()=> {

});

});

Another option is to remove the comment from the file being linted and define the globals in the configuration, for example:

importglobalsfrom"globals";

exportdefault [

{

files: [

],

languageOptions: {

globals: {

...globals.mocha

}

}

}

];

In eslintrc files, use the`extends` property to use predefined configs. ESLint comes with two predefined configs that you can access as strings: