| /** @category Validation Rules */ |
| import { GraphQLError } from '../../error/GraphQLError.mjs'; |
| import { print } from '../../language/printer.mjs'; |
| import { isCompositeType } from '../../type/definition.mjs'; |
| import { typeFromAST } from '../../utilities/typeFromAST.mjs'; |
| |
| /** |
| * Fragments on composite type |
| * |
| * Fragments use a type condition to determine if they apply, since fragments |
| * can only be spread into a composite type (object, interface, or union), the |
| * type condition must also be a composite type. |
| * |
| * See https://spec.graphql.org/draft/#sec-Fragments-On-Composite-Types |
| * @param context - The validation context used while checking the document. |
| * @returns A visitor that reports validation errors for this rule. |
| * @example |
| * ```ts |
| * import { buildSchema, parse, validate } from 'graphql'; |
| * import { FragmentsOnCompositeTypesRule } from 'graphql/validation'; |
| * |
| * const schema = buildSchema(` |
| * type Query { |
| * name: String |
| * } |
| * `); |
| * |
| * const invalidDocument = parse(` |
| * fragment Bad on String { length } |
| * `); |
| * const invalidErrors = validate(schema, invalidDocument, [FragmentsOnCompositeTypesRule]); |
| * |
| * invalidErrors.length; // => 1 |
| * |
| * const validDocument = parse(` |
| * fragment Good on Query { name } |
| * `); |
| * const validErrors = validate(schema, validDocument, [FragmentsOnCompositeTypesRule]); |
| * |
| * validErrors; // => [] |
| * ``` |
| */ |
| export function FragmentsOnCompositeTypesRule(context) { |
| return { |
| InlineFragment(node) { |
| const typeCondition = node.typeCondition; |
| |
| if (typeCondition) { |
| const type = typeFromAST(context.getSchema(), typeCondition); |
| |
| if (type && !isCompositeType(type)) { |
| const typeStr = print(typeCondition); |
| context.reportError( |
| new GraphQLError( |
| `Fragment cannot condition on non composite type "${typeStr}".`, |
| { |
| nodes: typeCondition, |
| }, |
| ), |
| ); |
| } |
| } |
| }, |
| |
| FragmentDefinition(node) { |
| const type = typeFromAST(context.getSchema(), node.typeCondition); |
| |
| if (type && !isCompositeType(type)) { |
| const typeStr = print(node.typeCondition); |
| context.reportError( |
| new GraphQLError( |
| `Fragment "${node.name.value}" cannot condition on non composite type "${typeStr}".`, |
| { |
| nodes: node.typeCondition, |
| }, |
| ), |
| ); |
| } |
| }, |
| }; |
| } |