eslint: AssertionError: ImportDeclaration should appear when the mode is ES6 and in the module context

“version”: “1.8.0” “escope”: “^3.2.0”

This issue is coming from escope in general (feel free to redirect there instead), though not sure which config option in eslint exists to enable modules mode (other than ecmaFeatures: { modules: true } which we already use).

We use ESLintTester (which seems is deprecated now, so maybe issue can be related as well). Trying to test the:

import Foo from 'Foo';

// Or type

import type Bar from 'Bar';

Fails with the assertion in the escope:

- AssertionError: ImportDeclaration should appear when the mode is ES6 and in the module context.
        at Referencer.ImportDeclaration (scripts/lint/eslint/node_modules/eslint/node_modules/escope/lib/referencer.js:711:17)
        at Referencer.Visitor.visit (scripts/lint/eslint/node_modules/eslint/node_modules/escope/node_modules/esrecurse/esrecurse.js:109:34)
        at Referencer.Visitor.visitChildren (scripts/lint/eslint/node_modules/eslint/node_modules/escope/node_modules/esrecurse/esrecurse.js:88:38)
        at Referencer.Program (scripts/lint/eslint/node_modules/eslint/node_modules/escope/lib/referencer.js:539:22)
        at Referencer.Visitor.visit (scripts/lint/eslint/node_modules/eslint/node_modules/escope/node_modules/esrecurse/esrecurse.js:109:34)
        at Object.analyze (scripts/lint/eslint/node_modules/eslint/node_modules/escope/lib/index.js:130:16)
        at EventEmitter.module.exports.api.verify (scripts/lint/eslint/node_modules/eslint/lib/eslint.js:736:35)
        at runRuleForItem (scripts/lint/eslint/node_modules/eslint/lib/testers/rule-tester.js:265:34)
        at testInvalidTemplate (scripts/lint/eslint/node_modules/eslint/lib/testers/rule-tester.js:302:26)
        at Spec.<anonymous> (scripts/lint/eslint/node_modules/eslint/lib/testers/rule-tester.js:370:21)

Is it a known issue? I didn’t find other config options to allow import in the tests.

Thanks!

About this issue

Original URL
State: closed
Created 9 years ago
Comments: 16 (3 by maintainers)

Commits related to this issue

Enable ECMA modules Ref: https://github.com/eslint/eslint/issues/4344 — committed to omipeople/eslint-config-omi by jumoel 8 years ago
Upgrade to fix error running eslint https://github.com/eslint/eslint/issues/4344 — committed to Automattic/wp-api-console by nylen 7 years ago
chore: disable prettier-eslint integration in VSCode Disable prettier-eslint integration in order to avoid the following error: ImportDeclaration should appear when the mode is ES6 and in th... — committed to loopbackio/loopback-next by bajtos 7 years ago
chore: disable prettier-eslint integration in VSCode Disable prettier-eslint integration in order to avoid the following error: ImportDeclaration should appear when the mode is ES6 and in th... — committed to loopbackio/loopback-next by bajtos 7 years ago
chore: disable prettier-eslint integration in VSCode Disable prettier-eslint integration in order to avoid the following error: ImportDeclaration should appear when the mode is ES6 and in th... — committed to loopbackio/loopback-next by bajtos 7 years ago

Most upvoted comments

I follow doc to add following options in .eslintrc.json file, and the issue is gone

  "parserOptions": {
    "ecmaVersion": 6,
    "sourceType": "module",
    "ecmaFeatures": {
      "modules": true
    }
  }

+50

gasolin on Mar 16, 2016

https://eslint.org/docs/user-guide/configuring#specifying-parser-options

adding the following lines in .eslintrc fixed the issue in my side.

"parserOptions": {
        "ecmaVersion": 6,
        "sourceType": "module",
        "ecmaFeatures": {
            "jsx": true
        }
    }

katwal-dipak on Aug 30, 2017

I got the same issue, I can’t find any babel-eslint@6 in stable version so I update to babel-eslint@6.0.0-beta.6, that solve the problem.

magrinj on Mar 24, 2016

In case this bites someone else, I had forgotten to move ecmaFeatures (at the top level) to parserOptions.ecmaFeatures in my config. For some reason, the former still works but not in all scenarios.

kumar303 on Aug 8, 2017

thanks @gasolin ! your fix worked for me (babel-eslint 6)

jamielesouef on Mar 31, 2016

For others seeing this error message, did you just upgrade eslint to 2.3.0? There’s an odd issue with babel-eslint depending on a module eslint no longer requires, https://github.com/eslint/eslint/issues/5476 npm install estraverse-fb will fix your issue in the short term.

Posting this here because it would have saved me some grief, since I did not come across this thread https://github.com/AtomLinter/linter-eslint/issues/469 first.

stkrzysiak on Mar 16, 2016