@graphql-eslint/eslint-plugin/esm/rules/no-scalar-result-type-on-mutation.js

GraphQL plugin for ESLint

import { isScalarType } from 'graphql';
import { requireGraphQLSchemaFromContext } from '../utils.js';
const RULE_ID = 'no-scalar-result-type-on-mutation';
export const rule = {
    meta: {
        type: 'suggestion',
        hasSuggestions: true,
        docs: {
            category: 'Schema',
            description: 'Avoid scalar result type on mutation type to make sure to return a valid state.',
            url: `https://github.com/B2o5T/graphql-eslint/blob/master/docs/rules/${RULE_ID}.md`,
            requiresSchema: true,
            examples: [
                {
                    title: 'Incorrect',
                    code: /* GraphQL */ `
            type Mutation {
              createUser: Boolean
            }
          `,
                },
                {
                    title: 'Correct',
                    code: /* GraphQL */ `
            type Mutation {
              createUser: User!
            }
          `,
                },
            ],
        },
        schema: [],
    },
    create(context) {
        const schema = requireGraphQLSchemaFromContext(RULE_ID, context);
        const mutationType = schema.getMutationType();
        if (!mutationType) {
            return {};
        }
        const selector = [
            `:matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value=${mutationType.name}]`,
            '> FieldDefinition > .gqlType Name',
        ].join(' ');
        return {
            [selector](node) {
                const typeName = node.value;
                const graphQLType = schema.getType(typeName);
                if (isScalarType(graphQLType)) {
                    context.report({
                        node,
                        message: `Unexpected scalar result type \`${typeName}\`.`,
                        suggest: [
                            {
                                desc: `Remove \`${typeName}\``,
                                fix: fixer => fixer.remove(node),
                            },
                        ],
                    });
                }
            },
        };
    },
};