Fix ValidationTests and possibleTypes logic

Author: wravery

include/Validation.h

@@ -250,6 +250,7 @@ class ValidateExecutableVisitor
 	VariableSet _referencedVariables;
 	FragmentSet _fragmentStack;
 	size_t _fieldCount = 0;
+	size_t _introspectionFieldCount = 0;
 	TypeFields _typeFields;
 	InputTypeFields _inputTypeFields;
 	ValidateType _scopedType;

include/graphqlservice/internal/Schema.h

@@ -177,7 +177,7 @@ class InterfaceType : public BaseType
 	GRAPHQLSERVICE_EXPORT static std::shared_ptr<InterfaceType> Make(
 		std::string_view name, std::string_view description);
 
-	GRAPHQLSERVICE_EXPORT void AddPossibleType(std::weak_ptr<ObjectType> possibleType);
+	GRAPHQLSERVICE_EXPORT void AddPossibleType(std::weak_ptr<BaseType> possibleType);
 	GRAPHQLSERVICE_EXPORT void AddInterfaces(
 		std::vector<std::shared_ptr<const InterfaceType>>&& interfaces);
 	GRAPHQLSERVICE_EXPORT void AddFields(std::vector<std::shared_ptr<const Field>>&& fields);
@@ -188,6 +188,8 @@ class InterfaceType : public BaseType
 		const noexcept final;
 	GRAPHQLSERVICE_EXPORT const std::vector<std::weak_ptr<const BaseType>>& possibleTypes()
 		const noexcept final;
+	GRAPHQLSERVICE_EXPORT const std::vector<std::shared_ptr<const InterfaceType>>& interfaces()
+		const noexcept final;
 
 private:
 	const std::string_view _name;

src/Introspection.cpp

@@ -5,12 +5,12 @@
 
 #include "graphqlservice/introspection/IntrospectionSchema.h"
 
-#include "graphqlservice/introspection/SchemaObject.h"
-#include "graphqlservice/introspection/TypeObject.h"
+#include "graphqlservice/introspection/DirectiveObject.h"
+#include "graphqlservice/introspection/EnumValueObject.h"
 #include "graphqlservice/introspection/FieldObject.h"
 #include "graphqlservice/introspection/InputValueObject.h"
-#include "graphqlservice/introspection/EnumValueObject.h"
-#include "graphqlservice/introspection/DirectiveObject.h"
+#include "graphqlservice/introspection/SchemaObject.h"
+#include "graphqlservice/introspection/TypeObject.h"
 
 namespace graphql::introspection {
 
@@ -168,9 +168,20 @@ std::optional<std::vector<std::shared_ptr<object::Type>>> Type::getPossibleTypes
 		possibleTypes.end(),
 		result->begin(),
 		[](const auto& entry) {
-			return std::make_shared<object::Type>(std::make_shared<Type>(entry.lock()));
+			auto typeEntry = entry.lock();
+
+			return typeEntry && typeEntry->kind() == introspection::TypeKind::OBJECT
+				? std::make_shared<object::Type>(std::make_shared<Type>(std::move(typeEntry)))
+				: std::shared_ptr<object::Type> {};
 		});
 
+	result->erase(std::remove_if(result->begin(),
+					  result->end(),
+					  [](const auto& entry) noexcept {
+						  return entry != nullptr;
+					  }),
+		result->cend());
+
 	return result;
 }
 
@@ -246,7 +257,8 @@ std::optional<std::string> Type::getSpecifiedByURL() const
 {
 	const auto specifiedByURL = _type->specifiedByURL();
 
-	return { specifiedByURL.empty() ? std::nullopt : std::make_optional<std::string>(specifiedByURL) };
+	return { specifiedByURL.empty() ? std::nullopt
+									: std::make_optional<std::string>(specifiedByURL) };
 }
 
 Field::Field(const std::shared_ptr<const schema::Field>& field)

src/Schema.cpp

@@ -235,8 +235,7 @@ void ObjectType::AddInterfaces(std::vector<std::shared_ptr<const InterfaceType>>
 
 	for (const auto& interface : _interfaces)
 	{
-		std::const_pointer_cast<InterfaceType>(interface)->AddPossibleType(
-			std::static_pointer_cast<ObjectType>(shared_from_this()));
+		std::const_pointer_cast<InterfaceType>(interface)->AddPossibleType(shared_from_this());
 	}
 }
 
@@ -278,14 +277,19 @@ InterfaceType::InterfaceType(init&& params)
 {
 }
 
-void InterfaceType::AddPossibleType(std::weak_ptr<ObjectType> possibleType)
+void InterfaceType::AddPossibleType(std::weak_ptr<BaseType> possibleType)
 {
 	_possibleTypes.push_back(possibleType);
 }
 
 void InterfaceType::AddInterfaces(std::vector<std::shared_ptr<const InterfaceType>>&& interfaces)
 {
 	_interfaces = std::move(interfaces);
+
+	for (const auto& interface : _interfaces)
+	{
+		std::const_pointer_cast<InterfaceType>(interface)->AddPossibleType(shared_from_this());
+	}
 }
 
 void InterfaceType::AddFields(std::vector<std::shared_ptr<const Field>>&& fields)
@@ -308,6 +312,11 @@ const std::vector<std::weak_ptr<const BaseType>>& InterfaceType::possibleTypes()
 	return _possibleTypes;
 }
 
+const std::vector<std::shared_ptr<const InterfaceType>>& InterfaceType::interfaces() const noexcept
+{
+	return _interfaces;
+}
+
 struct UnionType::init
 {
 	std::string_view name;

src/Validation.cpp

@@ -403,7 +403,15 @@ ValidateExecutableVisitor::ValidateExecutableVisitor(std::shared_ptr<schema::Sch
 			{
 				const auto& possibleTypes = entry.second->possibleTypes();
 
-				matchingTypes.reserve(possibleTypes.size());
+				if (kind == introspection::TypeKind::INTERFACE)
+				{
+					matchingTypes.reserve(possibleTypes.size() + 1);
+					matchingTypes.emplace(name);
+				}
+				else
+				{
+					matchingTypes.reserve(possibleTypes.size());
+				}
 
 				for (const auto& possibleType : possibleTypes)
 				{
@@ -773,26 +781,46 @@ void ValidateExecutableVisitor::visitOperationDefinition(const peg::ast_node& op
 	}
 
 	_scopedType = itrType->second;
+	_introspectionFieldCount = 0;
 	_fieldCount = 0;
 
 	const auto& selection = *operationDefinition.children.back();
 
 	visitSelection(selection);
 
-	if (_fieldCount > 1 && operationType == strSubscription)
+	if (operationType == strSubscription)
 	{
-		// https://spec.graphql.org/October2021/#sec-Single-root-field
-		auto position = operationDefinition.begin();
-		std::ostringstream error;
+		if (_fieldCount > 1)
+		{
+			// https://spec.graphql.org/October2021/#sec-Single-root-field
+			auto position = operationDefinition.begin();
+			std::ostringstream error;
 
-		error << "Subscription with more than one root field";
+			error << "Subscription with more than one root field";
 
-		if (!operationName.empty())
-		{
-			error << " name: " << operationName;
+			if (!operationName.empty())
+			{
+				error << " name: " << operationName;
+			}
+
+			_errors.push_back({ error.str(), { position.line, position.column } });
 		}
 
-		_errors.push_back({ error.str(), { position.line, position.column } });
+		if (_introspectionFieldCount != 0)
+		{
+			// https://spec.graphql.org/October2021/#sec-Single-root-field
+			auto position = operationDefinition.begin();
+			std::ostringstream error;
+
+			error << "Subscription with Introspection root field";
+
+			if (!operationName.empty())
+			{
+				error << " name: " << operationName;
+			}
+
+			_errors.push_back({ error.str(), { position.line, position.column } });
+		}
 	}
 
 	_scopedType.reset();
@@ -1622,7 +1650,7 @@ void ValidateExecutableVisitor::visitField(const peg::ast_node& field)
 	std::list<std::string_view> argumentNames;
 
 	peg::on_first_child<peg::arguments>(field,
-		[this, &name, &validateArguments, &argumentLocations, &argumentNames](
+		[this, name, &validateArguments, &argumentLocations, &argumentNames](
 			const peg::ast_node& child) {
 			for (auto& argument : child.children)
 			{
@@ -1760,8 +1788,10 @@ void ValidateExecutableVisitor::visitField(const peg::ast_node& field)
 		auto outerType = std::move(_scopedType);
 		auto outerFields = std::move(_selectionFields);
 		auto outerFieldCount = _fieldCount;
+		auto outerIntrospectionFieldCount = _introspectionFieldCount;
 
 		_fieldCount = 0;
+		_introspectionFieldCount = 0;
 		_selectionFields.clear();
 		_scopedType = std::move(innerType);
 
@@ -1771,6 +1801,7 @@ void ValidateExecutableVisitor::visitField(const peg::ast_node& field)
 		_scopedType = std::move(outerType);
 		_selectionFields = std::move(outerFields);
 		subFieldCount = _fieldCount;
+		_introspectionFieldCount = outerIntrospectionFieldCount;
 		_fieldCount = outerFieldCount;
 	}
 
@@ -1787,6 +1818,14 @@ void ValidateExecutableVisitor::visitField(const peg::ast_node& field)
 	}
 
 	++_fieldCount;
+
+	constexpr auto c_introspectionFieldPrefix = R"gql(__)gql"sv;
+
+	if (name.size() >= c_introspectionFieldPrefix.size()
+		&& name.substr(0, c_introspectionFieldPrefix.size()) == c_introspectionFieldPrefix)
+	{
+		++_introspectionFieldCount;
+	}
 }
 
 void ValidateExecutableVisitor::visitFragmentSpread(const peg::ast_node& fragmentSpread)

test/ValidationTests.cpp

@@ -268,7 +268,7 @@ TEST_F(ValidationExamplesCase, CounterExample112)
 
 	ASSERT_EQ(errors.size(), 1);
 	EXPECT_EQ(
-		R"js({"message":"Subscription with more than one root field name: sub","locations":[{"line":1,"column":1}]})js",
+		R"js({"message":"Subscription with Introspection root field name: sub","locations":[{"line":1,"column":1}]})js",
 		response::toJSON(std::move(errors[0])))
 		<< "error should match";
 }