@adguard/aglint/dist/linter/rules/duplicated-modifiers.js

Universal adblock filter list linter.

/*
 * AGLint v3.0.0 (build date: Wed, 21 May 2025 13:24:14 GMT)
 * (c) 2025 AdGuard Software Ltd.
 * Released under the MIT license
 * https://github.com/AdguardTeam/AGLint#readme
 */
import { RuleCategory } from '@adguard/agtree';
import { SEVERITY } from '../severity.js';

/**
 * Rule that checks if a network rule contains multiple same modifiers
 */
const DuplicatedModifiers = {
    meta: {
        severity: SEVERITY.error,
    },
    events: {
        onRule: (context) => {
            // Get actually iterated adblock rule
            const ast = context.getActualAdblockRuleAst();
            // Check if the rule is a basic network rule
            if (ast.category === RuleCategory.Network && ast.type === 'NetworkRule') {
                // Store which modifiers are already present
                const occurred = new Set();
                // This check is only relevant if there are at least two modifiers
                if (!ast.modifiers || ast.modifiers.children.length < 2) {
                    return;
                }
                for (const modifier of ast.modifiers.children) {
                    const name = modifier.name.value;
                    const nameToLowerCase = name.toLowerCase();
                    if (!occurred.has(nameToLowerCase)) {
                        occurred.add(nameToLowerCase);
                    }
                    else {
                        // Report if a modifier is occurring more than once
                        context.report({
                            message: `The modifier "${name}" is used multiple times, but it should be used only once`,
                            node: modifier,
                        });
                    }
                }
            }
        },
    },
};

export { DuplicatedModifiers };