import { GraphQLError } from '../../error/GraphQLError' ; import type { ASTVisitor } from '../../language/visitor' ; import type { ValidationContext } from '../ValidationContext' ; /**
 * Known fragment names
 *
 * A GraphQL document is only valid if all `...Fragment` fragment spreads refer
 * to fragments defined in the same document.
 *
 * See https://spec.graphql.org/draft/#sec-Fragment-spread-target-defined
 */ export function KnownFragmentNamesRule ( context ) { return { FragmentSpread ( node ) { const fragmentName = node . name . value ; const fragment = context . getFragment ( fragmentName ) ; if ( ! fragment ) { context . reportError ( new GraphQLError ( `Unknown fragment "${ fragmentName }".` , node . name ) ) ; } } , } ; }