'no-undef' error with optional chaining operator in v7.5.0

Hi,

In our code, we often use the optional chaining operator E.g: const valid = formContext?.formState?.isSubmitSuccessful But every time we do need to disable the ‘no-undef’ rule in order to not get any error.

We have then decided to update Eslint to v 7.5.0 and it’s plugging too, where needed. After updating the EsLint version to 7.5.0 we expected to do not get anymore the no-undef error; but we still do

EXPECTATION Shouldn’t eslint be able to recognize we are using the optional chaining operator and do not return any no-undef error?

We are using the default parser and, as suggested in the docs, added the parserOption proper config.

I am aware there are few similar errors, but they used Bable as a parser or had an older version. Thank you!

• **ESLint Version: 7.5.0
• **Node Version: 10.15.0
• **npm Version: 6.4.1
• **Operating System: macOS Catalina

**What parser: default

CONFIG:

module.exports = {
  parserOptions: {
    ecmaVersion: 2020,
  },
  extends: ['airbnb-typescript', 'plugin:prettier/recommended', 'prettier'],
  plugins: ['cup', 'header', 'prettier', 'react-hooks'],
  env: {
    jest: true,
  },
  globals: {
    page: true,
    browser: true,
    context: true,
    cy: true,
    Cypress: true,
    window: true,
  },
  rules: {
    'no-undef': 'off',
    'react/prop-types': 'off',
    'react/forbid-prop-types': 'error',
    'react-hooks/rules-of-hooks': 'error',
    'react-hooks/exhaustive-deps': 'warn',
    'import/no-extraneous-dependencies': [
      'error',
      {optionalDependencies: false, devDependencies: true},
    ],
    'import/prefer-default-export': 'off',
    'arrow-body-style': ['error', 'as-needed'],
    'react/jsx-one-expression-per-line': 'off',
    '@typescript-eslint/no-explicit-any': 'error',
    'import/no-unresolved': ['error', {ignore: ['csstype']}],
    'prettier/prettier': [
      'error',
      {
        singleQuote: true,
        trailingComma: 'all',
        bracketSpacing: false,
      },
    ],
  },
  overrides: [
    {
      files: ['*.js'],
      rules: {
        '@typescript-eslint/no-var-requires': 'off',
      },
    },
    {
      files: ['*.tsx'],
      env: {
        browser: true,
      },
    },
    {
      files: ['*.test.ts', '*.test.tsx'],
      rules: {
        '@typescript-eslint/no-explicit-any': 'off',
      },
    },
    {
      files: ['src/!(test)/*.ts', 'src/!(test)/*.tsx'],
      rules: {
        'import/no-extraneous-dependencies': [
          'error',
          {optionalDependencies: false, devDependencies: false},
        ],
      },
    },
    {
      files: ['site/**/*.ts', 'site/**/*.tsx'],
      rules: {
        'react/display-name': 'off',
        'import/no-unresolved': [
          'error',
          {ignore: ['newskit', 'csstype', '@components/page-title']},
        ],
      },
    },
    {
      files: ['cypress/**/*.spec.js'],
      env: {
        mocha: true,
      },
    },
  ],
};

[Vanals]

In that case it seems like it might be a bug on that parser. Can you file an issue with this information on that repo?

Will do, thanks for your guidance 🙏

[ljharb]

Yes, the important bits are the parser setting. Please update (wrap it in <details>/</details> and it won’t be as bothersome to readers, but make sure there’s a blank line before the output or it won’t highlight properly) with the entire result. You can | pbcopy and it’ll dump the entire output directly in your clipboard.