graphql/utilities/typeFromAST.mjs

A Query Language and Runtime which can target any service.

import inspect from '../jsutils/inspect';
import invariant from '../jsutils/invariant';
import { Kind } from '../language/kinds';
import { GraphQLList, GraphQLNonNull } from '../type/definition';
/**
 * Given a Schema and an AST node describing a type, return a GraphQLType
 * definition which applies to that type. For example, if provided the parsed
 * AST node for `[User]`, a GraphQLList instance will be returned, containing
 * the type called "User" found in the schema. If a type called "User" is not
 * found in the schema, then undefined will be returned.
 */

/* eslint-disable no-redeclare */

export function typeFromAST(schema, typeNode) {
  /* eslint-enable no-redeclare */
  var innerType;

  if (typeNode.kind === Kind.LIST_TYPE) {
    innerType = typeFromAST(schema, typeNode.type);
    return innerType && GraphQLList(innerType);
  }

  if (typeNode.kind === Kind.NON_NULL_TYPE) {
    innerType = typeFromAST(schema, typeNode.type);
    return innerType && GraphQLNonNull(innerType);
  }

  /* istanbul ignore else */
  if (typeNode.kind === Kind.NAMED_TYPE) {
    return schema.getType(typeNode.name.value);
  } // Not reachable. All possible type nodes have been considered.


  /* istanbul ignore next */
  invariant(false, 'Unexpected type node: ' + inspect(typeNode));
}