| import { GraphQLError } from '../../error/GraphQLError.mjs'; |
| |
| /** |
| * Unique fragment names |
| * |
| * A GraphQL document is only valid if all defined fragments have unique names. |
| * |
| * See https://spec.graphql.org/draft/#sec-Fragment-Name-Uniqueness |
| */ |
| export function UniqueFragmentNamesRule(context) { |
| const knownFragmentNames = Object.create(null); |
| return { |
| OperationDefinition: () => false, |
| |
| FragmentDefinition(node) { |
| const fragmentName = node.name.value; |
| |
| if (knownFragmentNames[fragmentName]) { |
| context.reportError( |
| new GraphQLError( |
| `There can be only one fragment named "${fragmentName}".`, |
| { |
| nodes: [knownFragmentNames[fragmentName], node.name], |
| }, |
| ), |
| ); |
| } else { |
| knownFragmentNames[fragmentName] = node.name; |
| } |
| |
| return false; |
| }, |
| }; |
| } |