supported schema description and add test for it

internal/gqlgen/gqlgen.go

@@ -83,10 +83,22 @@ func NewExecutableSchema(filenames ...string) (*ExecutableSchema, error) {
 }
 
 type ExecutableSchema struct {
-	ParsedSchema *ast.Schema
+	ParsedSchema      *ast.Schema
+	wantReservedTypes bool
 }
 
-func (e *ExecutableSchema) Exec(oc *graphql.OperationContext) *bytes.Buffer {
+type ExecOption func(es *ExecutableSchema)
+
+func WithReservedTypes(want bool) ExecOption {
+	return func(es *ExecutableSchema) {
+		es.wantReservedTypes = want
+	}
+}
+
+func (e *ExecutableSchema) Exec(oc *graphql.OperationContext, opts ...ExecOption) *bytes.Buffer {
+	for _, opt := range opts {
+		opt(e)
+	}
 	ec := executionContext{oc, e}
 	data := ec._Query(context.Background(), oc.Operation.SelectionSet)
 	var buf bytes.Buffer
@@ -100,7 +112,7 @@ type executionContext struct {
 }
 
 func (ec *executionContext) introspectSchema() *wrapper.Schema {
-	return wrapper.WrapSchema(ec.ParsedSchema)
+	return wrapper.WrapSchema(ec.ParsedSchema, wrapper.WithReservedTypes(ec.wantReservedTypes))
 }
 
 func (ec *executionContext) introspectType(name string) *wrapper.Type {
@@ -559,6 +571,8 @@ func (ec *executionContext) ___Schema(ctx context.Context, sel ast.SelectionSet,
 			if out.Values[i] == gql.Null {
 				invalids++
 			}
+		case "description":
+			out.Values[i] = gql.MarshalString(obj.Description())
 		default:
 			panic("unknown field " + strconv.Quote(field.Name))
 		}

internal/gqlgen/gqlgen_test.go

@@ -101,7 +101,7 @@ func TestExec(t *testing.T) {
 			ParsedSchema: AST,
 		}
 
-		resp := es.Exec(oc)
+		resp := es.Exec(oc, gqlgen.WithReservedTypes(true))
 
 		return resp.Bytes(), nil
 	})

internal/gqlgen/gqlgen_test.yml

@@ -240,7 +240,9 @@ tests:
         }
       query: |
         {
-          __schema { description }
+          __schema {
+            description
+          }
         }
       json: |
         {"__schema":{"description":"This is a simple schema"}}

internal/wrapper/schema.go

@@ -7,13 +7,25 @@ import (
 	"github.com/Code-Hex/gqlparser/v2/ast"
 )
 
+type WrapSchemaOption func(s *Schema)
+
+func WithReservedTypes(want bool) WrapSchemaOption {
+	return func(s *Schema) {
+		s.wantReservedTypes = want
+	}
+}
+
 type Schema struct {
-	schema *ast.Schema
+	schema            *ast.Schema
+	wantReservedTypes bool
 }
 
 func (s *Schema) Types() []Type {
 	types := make([]Type, 0, len(s.schema.Types))
 	for _, typ := range s.schema.Types {
+		if !s.wantReservedTypes && strings.HasPrefix(typ.Name, "__") {
+			continue
+		}
 		types = append(types, *WrapTypeFromDef(s.schema, typ))
 	}
 	sort.Slice(types, func(i, j int) bool {

internal/wrapper/wrapper.go

@@ -32,8 +32,12 @@ type (
 	}
 )
 
-func WrapSchema(schema *ast.Schema) *Schema {
-	return &Schema{schema: schema}
+func WrapSchema(schema *ast.Schema, opts ...WrapSchemaOption) *Schema {
+	s := &Schema{schema: schema}
+	for _, opt := range opts {
+		opt(s)
+	}
+	return s
 }
 
 func (f *EnumValue) IsDeprecated() bool {