platform/packages/graphql/graphql_schema/test/validation_test.dart

import 'package:graphql_schema/graphql_schema.dart';
import 'package:test/test.dart';

void main() {
  var typeType = enumTypeFromStrings('Type', [
    'FIRE',
    'WATER',
    'GRASS',
  ]);

  var pokemonType = objectType('Pokémon', fields: [
    field(
      'name',
      graphQLString.nonNullable(),
    ),
    field(
      'type',
      typeType,
    ),
  ]);

  var isValidPokemon = predicate(
      (x) =>
          pokemonType.validate('@root', x as Map<String, dynamic>).successful,
      'is a valid Pokémon');

  var throwsATypeError = throwsA(predicate(
      (x) => x is TypeError || x is CastError, 'is a type or cast error'));

  test('object accepts valid input', () {
    expect({'name': 'Charmander', 'type': 'FIRE'}, isValidPokemon);
  });

  test('mismatched scalar type', () {
    expect(() => pokemonType.validate('@root', {'name': 24}), throwsATypeError);
  });

  test('empty passed for non-nullable', () {
    expect(<String, dynamic>{}, isNot(isValidPokemon));
  });

  test('null passed for non-nullable', () {
    expect({'name': null}, isNot(isValidPokemon));
  });

  test('rejects extraneous fields', () {
    expect({'name': 'Vulpix', 'foo': 'bar'}, isNot(isValidPokemon));
  });

  test('enum accepts valid value', () {
    expect(typeType.validate('@root', 'FIRE').successful, true);
  });

  test('enum rejects invalid value', () {
    expect(typeType.validate('@root', 'POISON').successful, false);
  });

  group('union type', () {
    var digimonType = objectType(
      'Digimon',
      fields: [
        field('size', graphQLFloat.nonNullable()),
      ],
    );

    var u = new GraphQLUnionType('Monster', [pokemonType, digimonType]);

    test('any of its types returns valid', () {
      expect(u.validate('@root', {'size': 32.0}).successful, true);
      expect(
          u.validate(
              '@root', {'name': 'Charmander', 'type': 'FIRE'}).successful,
          true);
    });
  });

  group('input object', () {
    var type = inputObjectType(
      'Foo',
      inputFields: [
        inputField('bar', graphQLString.nonNullable()),
        inputField('baz', graphQLFloat.nonNullable()),
      ],
    );

    test('accept valid input', () {
      expect(type.validate('@root', {'bar': 'a', 'baz': 2.0}).value,
          {'bar': 'a', 'baz': 2.0});
    });

    test('error on missing non-null fields', () {
      expect(type.validate('@root', {'bar': 'a'}).successful, false);
    });

    test('error on unrecognized fields', () {
      expect(
          type.validate(
              '@root', {'bar': 'a', 'baz': 2.0, 'franken': 'stein'}).successful,
          false);
    });
  });
}