From b25f0c52ac01857a82dda20ec2b646c7ae90cd7d Mon Sep 17 00:00:00 2001
From: Alex Beregszaszi <alex@rtfs.hu>
Date: Sat, 12 Aug 2017 00:45:37 +0100
Subject: Reject the creation of interface with the new statement

---
 libsolidity/analysis/TypeChecker.cpp | 6 ++++++
 libsolidity/ast/Types.cpp            | 3 +++
 2 files changed, 9 insertions(+)

(limited to 'libsolidity')

diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 32d078fd..f70b75d3 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -429,6 +429,10 @@ void TypeChecker::endVisit(InheritanceSpecifier const& _inheritance)
 	if (base->isLibrary())
 		m_errorReporter.typeError(_inheritance.location(), "Libraries cannot be inherited from.");
 
+	// Interface can have no constructors - no need to validate
+	if (base->contractKind() == ContractDefinition::ContractKind::Interface)
+		return;
+
 	auto const& arguments = _inheritance.arguments();
 	TypePointers parameterTypes = ContractType(*base).newExpressionType()->parameterTypes();
 	if (!arguments.empty() && parameterTypes.size() != arguments.size())
@@ -1554,6 +1558,8 @@ void TypeChecker::endVisit(NewExpression const& _newExpression)
 
 		if (!contract)
 			m_errorReporter.fatalTypeError(_newExpression.location(), "Identifier is not a contract.");
+		if (contract->contractKind() == ContractDefinition::ContractKind::Interface)
+				m_errorReporter.fatalTypeError(_newExpression.location(), "Cannot instantiate an interface.");
 		if (!contract->annotation().unimplementedFunctions.empty())
 			m_errorReporter.typeError(
 				_newExpression.location(),
diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index e6664895..adf41229 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -2140,6 +2140,8 @@ FunctionTypePointer FunctionType::newExpressionType(ContractDefinition const& _c
 	strings parameterNames;
 	StateMutability stateMutability = StateMutability::NonPayable;
 
+	solAssert(_contract.contractKind() != ContractDefinition::ContractKind::Interface, "");
+
 	if (constructor)
 	{
 		for (ASTPointer<VariableDeclaration> const& var: constructor->parameters())
@@ -2150,6 +2152,7 @@ FunctionTypePointer FunctionType::newExpressionType(ContractDefinition const& _c
 		if (constructor->isPayable())
 			stateMutability = StateMutability::Payable;
 	}
+
 	return make_shared<FunctionType>(
 		parameters,
 		TypePointers{make_shared<ContractType>(_contract)},
-- 
cgit