@maniascript/mslint/dist/lib/rules/no-dupe-keys.js

ManiaScript linter

import {} from '../linter/rule.js';
import { ArrayExpression } from '@maniascript/parser';
import { equalLiterals, getNodeText } from '../linter/ast-utils.js';
function keyAlreadyExists(key, previousKeys) {
    for (const previousKey of previousKeys) {
        if (equalLiterals(key, previousKey)) {
            return true;
        }
    }
    return false;
}
export const noDupeKeys = {
    meta: {
        id: 'no-dupe-keys',
        description: 'Forbid duplicate keys in associative arrays',
        recommended: true
    },
    create(context) {
        return {
            'ArrayExpression:exit': (node) => {
                if (node instanceof ArrayExpression && node.isAssociative && node.values.length > 1) {
                    const keys = new Set();
                    for (const { key } of node.values) {
                        if (key !== undefined) {
                            if (keyAlreadyExists(key, keys)) {
                                context.report(key, `Duplicate key '${getNodeText(key, context.tokens)}'`);
                            }
                            else {
                                keys.add(key);
                            }
                        }
                    }
                }
            }
        };
    }
};