Add some sort of comment-based annotation to tell CodeMirror which style to use.

CodeEditor's JSHint allows in-page customization of linter rules using comments like /* jshint esversion:10 */ and similar. I think the same will be possible with ESlint?

Alternatively, it could be stored as page prop

Page props are an artifact of parsing. So you'll need some kind of annotation in the text to begin with.

In T394964#10854824, @SD0001 wrote:

CodeEditor's JSHint allows in-page customization of linter rules using comments like /* jshint esversion:10 */ and similar. I think the same will be possible with ESlint?

Unfortunately, it is not possible with ESLint: https://eslint.org/docs/latest/use/configure/language-options-deprecated#specifying-parser-options

In T394964#10854996, @Bhsd wrote:

In T394964#10854824, @SD0001 wrote:

CodeEditor's JSHint allows in-page customization of linter rules using comments like /* jshint esversion:10 */ and similar. I think the same will be possible with ESlint?

Unfortunately, it is not possible with ESLint: https://eslint.org/docs/latest/use/configure/language-options-deprecated#specifying-parser-options

Customizing esversion specifically is not possible, yes, but in general it can be done for other options: https://eslint.org/docs/latest/use/configure/rules#using-configuration-comments, assuming we've not optimized away this functionality in the browserfied build.

In T394964#10855075, @SD0001 wrote:

Customizing esversion specifically is not possible, yes, but in general it can be done for other options: https://eslint.org/docs/latest/use/configure/rules#using-configuration-comments, assuming we've not optimized away this functionality in the browserfied build.

Broadly speaking, yes, inline configuration is supported. However, the es-x plugin is not available from the browserified version.

Change #1273213 had a related patch set uploaded (by Bhsd; author: Bhsd):

[mediawiki/extensions/CodeMirror@master] CodeMirrorWorker: getLintConfig

https://gerrit.wikimedia.org/r/1273213

Change #1273213 merged by jenkins-bot:

[mediawiki/extensions/CodeMirror@master] CodeMirrorWorker: getLintConfig

https://gerrit.wikimedia.org/r/1273213

At the current stage (after the deployment next week), a user can customize the client-side linting rules like this:

mw.hook( 'ext.CodeMirror.ready' ).add( ( cm ) => {
    const { worker } = cm.langExtension;
    switch ( cm.mode ) {
        // WikiLint for Wikitext
        case 'mediawiki':
            worker.onload( async () => {
                const lintConfig = await worker.getLintConfig();
                $.extend( true, lintConfig, {
                    rules: {
                        ruleName: severity,
                        // e.g.
                        'tag-like': 0
                    }
                } );
                worker.setLintConfig( lintConfig );
            } );
            break;

        // ESLint for JavaScript
        case 'javascript':
            worker.onload( () => {
                worker.setConfig( {
                    rules: {
                        ruleName: severity,
                        // e.g.
                        semi: 2
                    }
                } );
            } );
            break;

        // Stylelint for CSS
        case 'css':
            worker.onload( () => {
                worker.setConfig( {
                    ruleName: option,
                    // e.g.
                    'color-named': 'never'
                } );
            } );
    }
} );

Change #1273489 had a related patch set uploaded (by Bhsd; author: Bhsd):

[mediawiki/extensions/CodeMirror@master] mediawiki worker: convention of rule customization

https://gerrit.wikimedia.org/r/1273489