@graphql-eslint/eslint-plugin/esm/rules/require-nullable-fields-with-oneof/index.js

GraphQL plugin for ESLint

import { Kind } from "graphql";
import { getNodeName } from "../../utils.js";
const RULE_ID = "require-nullable-fields-with-oneof", rule = {
  meta: {
    type: "suggestion",
    docs: {
      category: "Schema",
      description: "Require `input` or `type` fields to be non-nullable with `@oneOf` directive.",
      url: `https://the-guild.dev/graphql/eslint/rules/${RULE_ID}`,
      examples: [
        {
          title: "Incorrect",
          code: (
            /* GraphQL */
            `
            input Input @oneOf {
              foo: String!
              b: Int
            }
          `
          )
        },
        {
          title: "Correct",
          code: (
            /* GraphQL */
            `
            input Input @oneOf {
              foo: String
              bar: Int
            }
          `
          )
        }
      ]
    },
    messages: {
      [RULE_ID]: '{{ nodeName }} must be nullable when "@oneOf" is in use'
    },
    schema: []
  },
  create(context) {
    return {
      "Directive[name.value=oneOf]"({ parent }) {
        if ([
          Kind.OBJECT_TYPE_DEFINITION,
          Kind.INPUT_OBJECT_TYPE_DEFINITION
        ].includes(parent.kind))
          for (const field of parent.fields || [])
            field.gqlType.kind === Kind.NON_NULL_TYPE && context.report({
              node: field.name,
              messageId: RULE_ID,
              data: { nodeName: getNodeName(field) }
            });
      }
    };
  }
};
export {
  rule
};