@theguild/federation-composition/esm/subgraph/validation/rules/unique-argument-names-rule.js

Open Source Composition library for Apollo Federation

import { GraphQLError } from 'graphql';
export function UniqueArgumentNamesRule(context) {
    return {
        Field: checkArgUniqueness,
        Directive: checkArgUniqueness,
    };
    function checkArgUniqueness(parentNode) {
        const argumentNodes = parentNode.arguments ?? [];
        const seenArgs = new Set();
        for (const argumentNode of argumentNodes) {
            if (seenArgs.has(argumentNode.name.value)) {
                context.reportError(new GraphQLError(`There can be only one argument named "${argumentNode.name.value}".`, {
                    extensions: {
                        code: 'INVALID_GRAPHQL',
                    },
                }));
            }
            else {
                seenArgs.add(argumentNode.name.value);
            }
        }
    }
}