func TestTypeSystem_ObjectsMustAdhereToInterfaceTheyImplement_AcceptsAnObjectWithAnEquivalentlyModifiedInterfaceField(t *testing.T) {
	anotherInterface := types.NewGraphQLInterfaceType(types.GraphQLInterfaceTypeConfig{
		Name: "AnotherInterface",
		ResolveType: func(value interface{}, info types.GraphQLResolveInfo) *types.GraphQLObjectType {
			return nil
		},
		Fields: types.GraphQLFieldConfigMap{
			"field": &types.GraphQLFieldConfig{
				Type: types.NewGraphQLNonNull(types.NewGraphQLList(types.GraphQLString)),
			},
		},
	})
	anotherObject := types.NewGraphQLObjectType(types.GraphQLObjectTypeConfig{
		Name:       "AnotherObject",
		Interfaces: []*types.GraphQLInterfaceType{anotherInterface},
		Fields: types.GraphQLFieldConfigMap{
			"field": &types.GraphQLFieldConfig{
				Type: types.NewGraphQLNonNull(types.NewGraphQLList(types.GraphQLString)),
			},
		},
	})
	_, err := schemaWithObjectFieldOfType(anotherObject)
	if err != nil {
		t.Fatalf(`unexpected error: %v for type "%v"`, err, anotherObject)
	}
}

func TestTypeSystem_DefinitionExample_StringifiesSimpleTypes(t *testing.T) {

	type Test struct {
		ttype    types.GraphQLType
		expected string
	}
	tests := []Test{
		Test{types.GraphQLInt, "Int"},
		Test{blogArticle, "Article"},
		Test{interfaceType, "Interface"},
		Test{unionType, "Union"},
		Test{enumType, "Enum"},
		Test{inputObjectType, "InputObject"},
		Test{types.NewGraphQLNonNull(types.GraphQLInt), "Int!"},
		Test{types.NewGraphQLList(types.GraphQLInt), "[Int]"},
		Test{types.NewGraphQLNonNull(types.NewGraphQLList(types.GraphQLInt)), "[Int]!"},
		Test{types.NewGraphQLList(types.NewGraphQLNonNull(types.GraphQLInt)), "[Int!]"},
		Test{types.NewGraphQLList(types.NewGraphQLList(types.GraphQLInt)), "[[Int]]"},
	}
	for _, test := range tests {
		ttypeStr := fmt.Sprintf("%v", test.ttype)
		if ttypeStr != test.expected {
			t.Fatalf(`expected %v , got: %v`, test.expected, ttypeStr)
		}
	}
}

func PluralIdentifyingRootField(config PluralIdentifyingRootFieldConfig) *types.GraphQLFieldConfig {
	inputArgs := types.GraphQLFieldConfigArgumentMap{}
	if config.ArgName != "" {
		inputArgs[config.ArgName] = &types.GraphQLArgumentConfig{
			Type: types.NewGraphQLNonNull(types.NewGraphQLList(types.NewGraphQLNonNull(config.InputType))),
		}
	}

	return &types.GraphQLFieldConfig{
		Description: config.Description,
		Type:        types.NewGraphQLList(config.OutputType),
		Args:        inputArgs,
		Resolve: func(p types.GQLFRParams) interface{} {
			inputs, ok := p.Args[config.ArgName]
			if !ok {
				return nil
			}

			if config.ResolveSingleInput == nil {
				return nil
			}
			switch inputs := inputs.(type) {
			case []interface{}:
				res := []interface{}{}
				for _, input := range inputs {
					r := config.ResolveSingleInput(input)
					res = append(res, r)
				}
				return res
			}
			return nil
		},
	}
}

func withModifiers(ttypes []types.GraphQLType) []types.GraphQLType {
	res := ttypes
	for _, ttype := range ttypes {
		res = append(res, types.NewGraphQLList(ttype))
	}
	for _, ttype := range ttypes {
		res = append(res, types.NewGraphQLNonNull(ttype))
	}
	for _, ttype := range ttypes {
		res = append(res, types.NewGraphQLNonNull(types.NewGraphQLList(ttype)))
	}
	return res
}

func TestTypeSystem_ListMustAcceptGraphQLTypes_RejectsANilTypeAsItemTypeOfList(t *testing.T) {
	result := types.NewGraphQLList(nil)
	expectedError := `Can only create List of a GraphQLType but got: <nil>.`
	if result.GetError() == nil || result.GetError().Error() != expectedError {
		t.Fatalf("Expected error: %v, got %v", expectedError, result.GetError())
	}
}

func TestTypeSystem_DefinitionExample_IdentifiesOutputTypes(t *testing.T) {
	type Test struct {
		ttype    types.GraphQLType
		expected bool
	}
	tests := []Test{
		Test{types.GraphQLInt, true},
		Test{objectType, true},
		Test{interfaceType, true},
		Test{unionType, true},
		Test{enumType, true},
		Test{inputObjectType, false},
	}
	for _, test := range tests {
		ttypeStr := fmt.Sprintf("%v", test.ttype)
		if types.IsOutputType(test.ttype) != test.expected {
			t.Fatalf(`expected %v , got: %v`, test.expected, ttypeStr)
		}
		if types.IsOutputType(types.NewGraphQLList(test.ttype)) != test.expected {
			t.Fatalf(`expected %v , got: %v`, test.expected, ttypeStr)
		}
		if types.IsOutputType(types.NewGraphQLNonNull(test.ttype)) != test.expected {
			t.Fatalf(`expected %v , got: %v`, test.expected, ttypeStr)
		}
	}
}

func TestLists_NonNullListOfNonNullFunc_ReturnsNull(t *testing.T) {
	ttype := types.NewGraphQLNonNull(types.NewGraphQLList(types.NewGraphQLNonNull(types.GraphQLInt)))

	// `data` is a function that return values
	// Note that its uses the expected signature `func() interface{} {...}`
	data := func() interface{} {
		return nil
	}
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"nest": nil,
		},
		Errors: []graphqlerrors.GraphQLFormattedError{
			graphqlerrors.GraphQLFormattedError{
				Message: "Cannot return null for non-nullable field DataType.test.",
				Locations: []location.SourceLocation{
					location.SourceLocation{
						Line:   1,
						Column: 10,
					},
				},
			},
		},
	}
	checkList(t, ttype, data, expected)
}

func TestLists_NullableListOfNonNullObjects_ContainsNull(t *testing.T) {
	ttype := types.NewGraphQLList(types.NewGraphQLNonNull(types.GraphQLInt))
	data := []interface{}{
		1, nil, 2,
	}
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"nest": map[string]interface{}{
				"test": nil,
			},
		},
		Errors: []graphqlerrors.GraphQLFormattedError{
			graphqlerrors.GraphQLFormattedError{
				Message: "Cannot return null for non-nullable field DataType.test.",
				Locations: []location.SourceLocation{
					location.SourceLocation{
						Line:   1,
						Column: 10,
					},
				},
			},
		},
	}
	checkList(t, ttype, data, expected)
}

func TestLists_NonNullListOfNonNullArrayOfFunc_ContainsNulls(t *testing.T) {
	ttype := types.NewGraphQLNonNull(types.NewGraphQLList(types.NewGraphQLNonNull(types.GraphQLInt)))

	// `data` is a slice of functions that return values
	// Note that its uses the expected signature `func() interface{} {...}`
	data := []interface{}{
		func() interface{} {
			return 1
		},
		func() interface{} {
			return nil
		},
		func() interface{} {
			return 2
		},
	}
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"nest": map[string]interface{}{
				"test": []interface{}{
					1, nil, 2,
				},
			},
		},
	}
	checkList(t, ttype, data, expected)
}

func TestTypeSystem_NonNullMustAcceptGraphQLTypes_AcceptsAnTypeAsNullableTypeOfNonNull(t *testing.T) {
	nullableTypes := []types.GraphQLType{
		types.GraphQLString,
		someScalarType,
		someObjectType,
		someUnionType,
		someInterfaceType,
		someEnumType,
		someInputObject,
		types.NewGraphQLList(types.GraphQLString),
		types.NewGraphQLList(types.NewGraphQLNonNull(types.GraphQLString)),
	}
	for _, ttype := range nullableTypes {
		result := types.NewGraphQLNonNull(ttype)
		if result.GetError() != nil {
			t.Fatalf(`unexpected error: %v for type "%v"`, result.GetError(), ttype)
		}
	}
}

func TestLists_ListOfNullableObjects_ReturnsNull(t *testing.T) {
	ttype := types.NewGraphQLList(types.GraphQLInt)
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"nest": map[string]interface{}{
				"test": nil,
			},
		},
	}
	checkList(t, ttype, nil, expected)
}

func TestLists_ListOfNullableObjects_ContainsNull(t *testing.T) {
	ttype := types.NewGraphQLList(types.GraphQLInt)
	data := []interface{}{
		1, nil, 2,
	}
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"nest": map[string]interface{}{
				"test": []interface{}{
					1, nil, 2,
				},
			},
		},
	}
	checkList(t, ttype, data, expected)
}

func TestTypeSystem_ListMustAcceptGraphQLTypes_AcceptsAnTypeAsItemTypeOfList(t *testing.T) {
	testTypes := withModifiers([]types.GraphQLType{
		types.GraphQLString,
		someScalarType,
		someEnumType,
		someObjectType,
		someUnionType,
		someInterfaceType,
	})
	for _, ttype := range testTypes {
		result := types.NewGraphQLList(ttype)
		if result.GetError() != nil {
			t.Fatalf(`unexpected error: %v for type "%v"`, result.GetError(), ttype)
		}
	}
}

// Describe [T!]! Array<T>
func TestLists_NonNullListOfNonNullObjects_ContainsValues(t *testing.T) {
	ttype := types.NewGraphQLNonNull(types.NewGraphQLList(types.NewGraphQLNonNull(types.GraphQLInt)))
	data := []interface{}{
		1, 2,
	}
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"nest": map[string]interface{}{
				"test": []interface{}{
					1, 2,
				},
			},
		},
	}
	checkList(t, ttype, data, expected)
}

func TestLists_NullableListOfNonNullFunc_ReturnsNull(t *testing.T) {
	ttype := types.NewGraphQLList(types.NewGraphQLNonNull(types.GraphQLInt))

	// `data` is a function that return values
	// Note that its uses the expected signature `func() interface{} {...}`
	data := func() interface{} {
		return nil
	}
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"nest": map[string]interface{}{
				"test": nil,
			},
		},
	}
	checkList(t, ttype, data, expected)
}

func ConnectionDefinitions(config ConnectionConfig) *GraphQLConnectionDefinitions {

	edgeType := types.NewGraphQLObjectType(types.GraphQLObjectTypeConfig{
		Name:        config.Name + "Edge",
		Description: "An edge in a connection",
		Fields: types.GraphQLFieldConfigMap{
			"node": &types.GraphQLFieldConfig{
				Type:        config.NodeType,
				Description: "The item at the end of the edge",
			},
			"cursor": &types.GraphQLFieldConfig{
				Type:        types.NewGraphQLNonNull(types.GraphQLString),
				Description: " cursor for use in pagination",
			},
		},
	})
	for fieldName, fieldConfig := range config.EdgeFields {
		edgeType.AddFieldConfig(fieldName, fieldConfig)
	}

	connectionType := types.NewGraphQLObjectType(types.GraphQLObjectTypeConfig{
		Name:        config.Name + "Connection",
		Description: "A connection to a list of items.",

		Fields: types.GraphQLFieldConfigMap{
			"pageInfo": &types.GraphQLFieldConfig{
				Type:        types.NewGraphQLNonNull(pageInfoType),
				Description: "Information to aid in pagination.",
			},
			"edges": &types.GraphQLFieldConfig{
				Type:        types.NewGraphQLList(edgeType),
				Description: "Information to aid in pagination.",
			},
		},
	})
	for fieldName, fieldConfig := range config.ConnectionFields {
		connectionType.AddFieldConfig(fieldName, fieldConfig)
	}

	return &GraphQLConnectionDefinitions{
		EdgeType:       edgeType,
		ConnectionType: connectionType,
	}
}

// Describe [T] Func()Array<T> // equivalent to Promise<Array<T>>
func TestLists_ListOfNullableFunc_ContainsValues(t *testing.T) {
	ttype := types.NewGraphQLList(types.GraphQLInt)

	// `data` is a function that return values
	// Note that its uses the expected signature `func() interface{} {...}`
	data := func() interface{} {
		return []interface{}{
			1, 2,
		}
	}
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"nest": map[string]interface{}{
				"test": []interface{}{
					1, 2,
				},
			},
		},
	}
	checkList(t, ttype, data, expected)
}

func TestFailsWhenAnIsTypeOfCheckIsNotMet(t *testing.T) {

	query := `{ specials { value } }`

	data := map[string]interface{}{
		"specials": []interface{}{
			testSpecialType{"foo"},
			testNotSpecialType{"bar"},
		},
	}

	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"specials": []interface{}{
				map[string]interface{}{
					"value": "foo",
				},
				nil,
			},
		},
		Errors: []graphqlerrors.GraphQLFormattedError{
			graphqlerrors.GraphQLFormattedError{
				Message:   `Expected value of type "SpecialType" but got: executor_test.testNotSpecialType.`,
				Locations: []location.SourceLocation{},
			},
		},
	}

	specialType := types.NewGraphQLObjectType(types.GraphQLObjectTypeConfig{
		Name: "SpecialType",
		IsTypeOf: func(value interface{}, info types.GraphQLResolveInfo) bool {
			if _, ok := value.(testSpecialType); ok {
				return true
			}
			return false
		},
		Fields: types.GraphQLFieldConfigMap{
			"value": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
				Resolve: func(ctx context.Context, p types.GQLFRParams) interface{} {
					return p.Source.(testSpecialType).Value
				},
			},
		},
	})
	schema, err := types.NewGraphQLSchema(types.GraphQLSchemaConfig{
		Query: types.NewGraphQLObjectType(types.GraphQLObjectTypeConfig{
			Name: "Query",
			Fields: types.GraphQLFieldConfigMap{
				"specials": &types.GraphQLFieldConfig{
					Type: types.NewGraphQLList(specialType),
					Resolve: func(ctx context.Context, p types.GQLFRParams) interface{} {
						return p.Source.(map[string]interface{})["specials"]
					},
				},
			},
		}),
	})
	if err != nil {
		t.Fatalf("Error in schema %v", err.Error())
	}

	// parse query
	ast := testutil.Parse(t, query)

	// execute
	ep := executor.ExecuteParams{
		Schema: schema,
		AST:    ast,
		Root:   data,
	}
	result := testutil.Execute(t, ep)
	if len(result.Errors) == 0 {
		t.Fatalf("wrong result, unexpected errors: %v", result.Errors)
	}
	if !reflect.DeepEqual(expected, result) {
		t.Fatalf("Unexpected result, Diff: %v", testutil.Diff(expected, result))
	}
}

//.........这里部分代码省略.........
		if !ok {
			return nil
		}
		// get and type assert argument
		sizeArg, ok := p.Args["size"].(int)
		if !ok {
			return nil
		}
		return picResolver(sizeArg)
	}
	dataType := types.NewGraphQLObjectType(types.GraphQLObjectTypeConfig{
		Name: "DataType",
		Fields: types.GraphQLFieldConfigMap{
			"a": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"b": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"c": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"d": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"e": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"f": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"pic": &types.GraphQLFieldConfig{
				Args: types.GraphQLFieldConfigArgumentMap{
					"size": &types.GraphQLArgumentConfig{
						Type: types.GraphQLInt,
					},
				},
				Type:    types.GraphQLString,
				Resolve: picResolverFn,
			},
		},
	})
	deepDataType := types.NewGraphQLObjectType(types.GraphQLObjectTypeConfig{
		Name: "DeepDataType",
		Fields: types.GraphQLFieldConfigMap{
			"a": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"b": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"c": &types.GraphQLFieldConfig{
				Type: types.NewGraphQLList(types.GraphQLString),
			},
			"deeper": &types.GraphQLFieldConfig{
				Type: types.NewGraphQLList(dataType),
			},
		},
	})

	// Exploring a way to have a GraphQLObjectType within itself
	// in this case DataType has DeepDataType has DataType
	dataType.AddFieldConfig("deep", &types.GraphQLFieldConfig{
		Type: deepDataType,
	})
	// in this case DataType has DataType
	dataType.AddFieldConfig("promise", &types.GraphQLFieldConfig{
		Type: dataType,
	})

	schema, err := types.NewGraphQLSchema(types.GraphQLSchemaConfig{
		Query: dataType,
	})
	if err != nil {
		t.Fatalf("Error in schema %v", err.Error())
	}

	// parse query
	astDoc := testutil.Parse(t, query)

	// execute
	args := map[string]interface{}{
		"size": 100,
	}
	operationName := "Example"
	ep := executor.ExecuteParams{
		Schema:        schema,
		Root:          data,
		AST:           astDoc,
		OperationName: operationName,
		Args:          args,
	}
	result := testutil.Execute(t, ep)
	if len(result.Errors) > 0 {
		t.Fatalf("wrong result, unexpected errors: %v", result.Errors)
	}
	if !reflect.DeepEqual(expected, result) {
		t.Fatalf("Unexpected result, Diff: %v", testutil.Diff(expected, result))
	}
}

func TestUnionIntersectionTypes_GetsExecutionInfoInResolver(t *testing.T) {

	var encounteredSchema *types.GraphQLSchema
	var encounteredRootValue interface{}

	var personType2 *types.GraphQLObjectType

	namedType2 := types.NewGraphQLInterfaceType(types.GraphQLInterfaceTypeConfig{
		Name: "Named",
		Fields: types.GraphQLFieldConfigMap{
			"name": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
		},
		ResolveType: func(value interface{}, info types.GraphQLResolveInfo) *types.GraphQLObjectType {
			encounteredSchema = &info.Schema
			encounteredRootValue = info.RootValue
			return personType2
		},
	})

	personType2 = types.NewGraphQLObjectType(types.GraphQLObjectTypeConfig{
		Name: "Person",
		Interfaces: []*types.GraphQLInterfaceType{
			namedType2,
		},
		Fields: types.GraphQLFieldConfigMap{
			"name": &types.GraphQLFieldConfig{
				Type: types.GraphQLString,
			},
			"friends": &types.GraphQLFieldConfig{
				Type: types.NewGraphQLList(namedType2),
			},
		},
	})

	schema2, _ := types.NewGraphQLSchema(types.GraphQLSchemaConfig{
		Query: personType2,
	})

	john2 := &testPerson{
		Name: "John",
		Friends: []testNamedType{
			liz,
		},
	}

	doc := `{ name, friends { name } }`
	expected := &types.GraphQLResult{
		Data: map[string]interface{}{
			"name": "John",
			"friends": []interface{}{
				map[string]interface{}{
					"name": "Liz",
				},
			},
		},
	}
	// parse query
	ast := testutil.Parse(t, doc)

	// execute
	ep := executor.ExecuteParams{
		Schema: schema2,
		AST:    ast,
		Root:   john2,
	}
	result := testutil.Execute(t, ep)
	if len(result.Errors) != len(expected.Errors) {
		t.Fatalf("Unexpected errors, Diff: %v", testutil.Diff(expected.Errors, result.Errors))
	}
	if !reflect.DeepEqual(expected, result) {
		t.Fatalf("Unexpected result, Diff: %v", testutil.Diff(expected, result))
	}
}