| // @flow strict |
| |
| import { GraphQLError } from '../../error/GraphQLError'; |
| import { type ASTVisitor } from '../../language/visitor'; |
| |
| import { type ASTValidationContext } from '../ValidationContext'; |
| |
| /** |
| * Unique operation names |
| * |
| * A GraphQL document is only valid if all defined operations have unique names. |
| */ |
| export function UniqueOperationNamesRule( |
| context: ASTValidationContext, |
| ): ASTVisitor { |
| const knownOperationNames = Object.create(null); |
| return { |
| OperationDefinition(node) { |
| const operationName = node.name; |
| if (operationName) { |
| if (knownOperationNames[operationName.value]) { |
| context.reportError( |
| new GraphQLError( |
| `There can be only one operation named "${operationName.value}".`, |
| [knownOperationNames[operationName.value], operationName], |
| ), |
| ); |
| } else { |
| knownOperationNames[operationName.value] = operationName; |
| } |
| } |
| return false; |
| }, |
| FragmentDefinition: () => false, |
| }; |
| } |