Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request? (put an "X" next to an item)

[ ] Documentation update
[x] Bug fix (template)
[ ] New rule (template)
[ ] Changes an existing rule (template)
[ ] Add autofix to a rule
[ ] Add a CLI option
[ ] Add something to the core
[ ] Other, please explain:

Tell us about your environment (npx eslint --env-info):

• Node version: v20.12.0
• npm version: v10.5.0
• Local ESLint version: v9.5.0
• Global ESLint version: no
• Operating System: windows

What parser are you using (place an "X" next to just one item)?

[x] Default (Espree)
[ ] @typescript-eslint/parser
[ ] @babel/eslint-parser
[ ] vue-eslint-parser
[ ] @angular-eslint/template-parser
[ ] Other

Please show your full configuration:

export default [];

What did you do? Please include the actual source code causing the issue.

// line 1
// line 2
/* eslint no-alert: [2 */

What did you expect to happen?

An error about invalid JSON in inlline config on line 3.

What actually happened? Please include the actual, raw output from ESLint.

Error on line 1 instead of line 3:

 1:1  error  Failed to parse JSON from ' "no-alert": [2': Expected ',' or ']' after array element in JSON at position 16

Playground Demo

What changes did you make? (Give an overview)

SourceCode#applyInlineConfig() was returning these errors without the loc property (line and column were directly on the error as received from the config comment parser) so the error loc start was defaulting to 1:1. I fixed this to return loc on the error, and also refactored code to create lint errors in the Linter rather than in the config comment parser. This also adds endLine and endColumn so the whole comment will be underlined.

Is there anything you'd like reviewers to focus on?

This bug was not introduced in #18448, we missed it earlier.