Explore configuration with real regex instead of strings

[lydell]

Now that ESLint 9 is here with Flat config written in JavaScript, it would be cool if it was possible to use regex literals instead of string literals when configuring this plugin.

Pros:

• No double escaping. Can write /\w/ instead of "\\w".
• Can choose flags. Like adding i for case in-sensitive.
• Can get more help from an IDE since it knows you are writing a regex.

What needs to be done:

• See if this is possible at all in Flat config.
• Figure out the eslintrc compatibility story.
• Update docs.
• Update tests.
• Support strings forever since it’s easy and then doesn’t force people to do boring update chores?

Example (the default groups):

import simpleImportSort from "eslint-plugin-simple-import-sort";

export default [
  {
    plugins: {
      "simple-import-sort": simpleImportSort,
    },
    rules: {
      "simple-import-sort/imports": ["error", {
        groups: [
          // Side effect imports.
          [/^\u0000/u],
          // Node.js builtins prefixed with `node:`.
          [/^node:/u],
          // Packages.
          // Things that start with a letter (or digit or underscore), or `@` followed by a letter.
          [/^@?\w/u],
          // Absolute imports and other imports such as Vue-style `@/foo`.
          // Anything not matched in another group.
          [/^/u],
          // Relative imports.
          // Anything that starts with a dot.
          [/^\./u],
        ]
      }],
    },
  },
];

[GollyJer]

regex literals would be cool. To solve your first problem I've been using String.raw

'simple-import-sort/imports': [
        'error',
        {
          groups: [
            // react, react-native, and side effect imports.
            ['^react$', '^react-native$', String.raw`^\u0000`],

            // Things that start with a letter (or digit or underscore), or `@` followed by a letter.
            [String.raw`^@?\w`],

            // Anything starting with a tilde. Anything starting with a dot.
            ['^~/', String.raw`^\.`],

            // type imports
            [String.raw`^@?\w.*\u0000$`, String.raw`^[^.].*\u0000$`, String.raw`^\..*\u0000$`],
          ],
        },

It's maybe slightly more readable and done via another eslint rule so I don't really have to think about it. 😛

[fisker]

See if this is possible at all in Flat config.
Figure out the eslintrc compatibility story.

In my experience, regex literal works for both flat config and eslintrc.

unicorn/prevent-abbreviation accepts Array<string | RegExp> for many years. https://github.com/sindresorhus/eslint-plugin-unicorn/blob/main/docs/rules/prevent-abbreviations.md#ignore