Merge pull request #4911 from ethereum/addressPayable

Payable and non-payable address type.

8 files changed, 154 insertions, 39 deletions

diff --git a/libsolidity/analysis/GlobalContext.cpp b/libsolidity/analysis/GlobalContext.cpp
index 3ac8fd47..cba2655c 100644
--- a/libsolidity/analysis/GlobalContext.cpp
+++ b/libsolidity/analysis/GlobalContext.cpp
@@ -56,10 +56,10 @@ m_magicVariables(vector<shared_ptr<MagicVariableDeclaration const>>{
 	make_shared<MagicVariableDeclaration>("revert", make_shared<FunctionType>(strings(), strings(), FunctionType::Kind::Revert, false, StateMutability::Pure)),
 	make_shared<MagicVariableDeclaration>("revert", make_shared<FunctionType>(strings{"string memory"}, strings(), FunctionType::Kind::Revert, false, StateMutability::Pure)),
 	make_shared<MagicVariableDeclaration>("ripemd160", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bytes20"}, FunctionType::Kind::RIPEMD160, false, StateMutability::Pure)),
-	make_shared<MagicVariableDeclaration>("selfdestruct", make_shared<FunctionType>(strings{"address"}, strings{}, FunctionType::Kind::Selfdestruct)),
+	make_shared<MagicVariableDeclaration>("selfdestruct", make_shared<FunctionType>(strings{"address payable"}, strings{}, FunctionType::Kind::Selfdestruct)),
 	make_shared<MagicVariableDeclaration>("sha256", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bytes32"}, FunctionType::Kind::SHA256, false, StateMutability::Pure)),
 	make_shared<MagicVariableDeclaration>("sha3", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bytes32"}, FunctionType::Kind::KECCAK256, false, StateMutability::Pure)),
-	make_shared<MagicVariableDeclaration>("suicide", make_shared<FunctionType>(strings{"address"}, strings{}, FunctionType::Kind::Selfdestruct)),
+	make_shared<MagicVariableDeclaration>("suicide", make_shared<FunctionType>(strings{"address payable"}, strings{}, FunctionType::Kind::Selfdestruct)),
 	make_shared<MagicVariableDeclaration>("tx", make_shared<MagicType>(MagicType::Kind::Transaction))
 })
 {
diff --git a/libsolidity/analysis/ReferencesResolver.cpp b/libsolidity/analysis/ReferencesResolver.cpp
index 4b678c3b..8a576e2e 100644
--- a/libsolidity/analysis/ReferencesResolver.cpp
+++ b/libsolidity/analysis/ReferencesResolver.cpp
@@ -119,11 +119,19 @@ bool ReferencesResolver::visit(ElementaryTypeName const& _typeName)
 		{
 			// for non-address types this was already caught by the parser
 			solAssert(_typeName.annotation().type->category() == Type::Category::Address, "");
-			if (!(
-				*_typeName.stateMutability() == StateMutability::Payable ||
-				*_typeName.stateMutability() == StateMutability::NonPayable
-			))
-				m_errorReporter.typeError(_typeName.location(), "Address types can only be payable or non-payable.");
+			switch(*_typeName.stateMutability())
+			{
+				case StateMutability::Payable:
+				case StateMutability::NonPayable:
+					_typeName.annotation().type = make_shared<AddressType>(*_typeName.stateMutability());
+					break;
+				default:
+					m_errorReporter.typeError(
+						_typeName.location(),
+						"Address types can only be payable or non-payable."
+					);
+					break;
+			}
 		}
 	}
 	return true;
diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 143ac109..e023dc38 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -571,6 +571,9 @@ TypePointers TypeChecker::typeCheckABIDecodeAndRetrieveReturnType(FunctionCall c
 			// data locations. Furthermore, storage can be a little dangerous and
 			// calldata is not really implemented anyway.
 			actualType = ReferenceType::copyForLocationIfReference(DataLocation::Memory, actualType);
+			// We force address payable for address types.
+			if (actualType->category() == Type::Category::Address)
+				actualType = make_shared<AddressType>(StateMutability::Payable);
 			solAssert(
 				!actualType->dataStoredIn(DataLocation::CallData) &&
 				!actualType->dataStoredIn(DataLocation::Storage),
@@ -1732,14 +1735,39 @@ bool TypeChecker::visit(FunctionCall const& _functionCall)
 				dataLoc = argRefType->location();
 			resultType = ReferenceType::copyForLocationIfReference(dataLoc, resultType);
 			if (!argType->isExplicitlyConvertibleTo(*resultType))
-				m_errorReporter.typeError(
-					_functionCall.location(),
-					"Explicit type conversion not allowed from \"" +
-					argType->toString() +
-					"\" to \"" +
-					resultType->toString() +
-					"\"."
-				);
+			{
+				if (resultType->category() == Type::Category::Contract && argType->category() == Type::Category::Address)
+				{
+					solAssert(dynamic_cast<ContractType const*>(resultType.get())->isPayable(), "");
+					solAssert(dynamic_cast<AddressType const*>(argType.get())->stateMutability() < StateMutability::Payable, "");
+					SecondarySourceLocation ssl;
+					if (auto const* identifier = dynamic_cast<Identifier const*>(arguments.front().get()))
+						if (auto const* variableDeclaration = dynamic_cast<VariableDeclaration const*>(identifier->annotation().referencedDeclaration))
+							ssl.append("Did you mean to declare this variable as \"address payable\"?", variableDeclaration->location());
+					m_errorReporter.typeError(
+						_functionCall.location(), ssl,
+						"Explicit type conversion not allowed from non-payable \"address\" to \"" +
+						resultType->toString() +
+						"\", which has a payable fallback function."
+					);
+				}
+				else
+					m_errorReporter.typeError(
+						_functionCall.location(),
+						"Explicit type conversion not allowed from \"" +
+						argType->toString() +
+						"\" to \"" +
+						resultType->toString() +
+						"\"."
+					);
+			}
+			if (resultType->category() == Type::Category::Address)
+			{
+				bool payable = true;
+				if (auto const* contractType = dynamic_cast<ContractType const*>(argType.get()))
+					payable = contractType->isPayable();
+				resultType = make_shared<AddressType>(payable ? StateMutability::Payable : StateMutability::NonPayable);
+			}
 		}
 		_functionCall.annotation().type = resultType;
 		_functionCall.annotation().isPure = isPure;
@@ -2103,7 +2131,7 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 				"after argument-dependent lookup in " + exprType->toString() +
 				(memberName == "value" ? " - did you forget the \"payable\" modifier?" : ".");
 		if (exprType->category() == Type::Category::Contract)
-			for (auto const& addressMember: AddressType().nativeMembers(nullptr))
+			for (auto const& addressMember: AddressType(StateMutability::Payable).nativeMembers(nullptr))
 				if (addressMember.name == memberName)
 				{
 					Identifier const* var = dynamic_cast<Identifier const*>(&_memberAccess.expression());
@@ -2354,7 +2382,7 @@ void TypeChecker::endVisit(Literal const& _literal)
 	if (_literal.looksLikeAddress())
 	{
 		// Assign type here if it even looks like an address. This prevents double errors for invalid addresses
-		_literal.annotation().type = make_shared<AddressType>();
+		_literal.annotation().type = make_shared<AddressType>(StateMutability::Payable);
 
 		string msg;
 		if (_literal.value().length() != 42) // "0x" + 40 hex digits
diff --git a/libsolidity/ast/ASTJsonConverter.cpp b/libsolidity/ast/ASTJsonConverter.cpp
index beab356c..8d52851a 100644
--- a/libsolidity/ast/ASTJsonConverter.cpp
+++ b/libsolidity/ast/ASTJsonConverter.cpp
@@ -394,10 +394,15 @@ bool ASTJsonConverter::visit(EventDefinition const& _node)
 
 bool ASTJsonConverter::visit(ElementaryTypeName const& _node)
 {
-	setJsonNode(_node, "ElementaryTypeName", {
+	std::vector<pair<string, Json::Value>> attributes = {
 		make_pair("name", _node.typeName().toString()),
 		make_pair("typeDescriptions", typePointerToJson(_node.annotation().type, true))
-	});
+	};
+
+	if (_node.stateMutability())
+		attributes.emplace_back(make_pair("stateMutability", stateMutabilityToString(*_node.stateMutability())));
+
+	setJsonNode(_node, "ElementaryTypeName", std::move(attributes));
 	return false;
 }
 
diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index a302203b..25702f19 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -299,7 +299,7 @@ TypePointer Type::fromElementaryTypeName(ElementaryTypeNameToken const& _type)
 	case Token::Byte:
 		return make_shared<FixedBytesType>(1);
 	case Token::Address:
-		return make_shared<AddressType>();
+		return make_shared<AddressType>(StateMutability::NonPayable);
 	case Token::Bool:
 		return make_shared<BoolType>();
 	case Token::Bytes:
@@ -340,6 +340,17 @@ TypePointer Type::fromElementaryTypeName(string const& _name)
 		}
 		return ref->copyForLocation(location, true);
 	}
+	else if (t->category() == Type::Category::Address)
+	{
+		if (nameParts.size() == 2)
+		{
+			if (nameParts[1] == "payable")
+				return make_shared<AddressType>(StateMutability::Payable);
+			else
+				solAssert(false, "Invalid state mutability for address type: " + nameParts[1]);
+		}
+		return make_shared<AddressType>(StateMutability::NonPayable);
+	}
 	else
 	{
 		solAssert(nameParts.size() == 1, "Storage location suffix only allowed for reference types");
@@ -439,21 +450,48 @@ MemberList::MemberMap Type::boundFunctions(Type const& _type, ContractDefinition
 	return members;
 }
 
+AddressType::AddressType(StateMutability _stateMutability):
+	m_stateMutability(_stateMutability)
+{
+	solAssert(m_stateMutability == StateMutability::Payable || m_stateMutability == StateMutability::NonPayable, "");
+}
+
 string AddressType::richIdentifier() const
 {
-	return "t_address";
+	if (m_stateMutability == StateMutability::Payable)
+		return "t_address_payable";
+	else
+		return "t_address";
+}
+
+bool AddressType::isImplicitlyConvertibleTo(Type const& _other) const
+{
+	if (_other.category() != category())
+		return false;
+	AddressType const& other = dynamic_cast<AddressType const&>(_other);
+
+	return other.m_stateMutability <= m_stateMutability;
 }
 
 bool AddressType::isExplicitlyConvertibleTo(Type const& _convertTo) const
 {
+	if (auto const* contractType = dynamic_cast<ContractType const*>(&_convertTo))
+		return (m_stateMutability >= StateMutability::Payable) || !contractType->isPayable();
 	return isImplicitlyConvertibleTo(_convertTo) ||
-		   _convertTo.category() == Category::Contract ||
 		   _convertTo.category() == Category::Integer ||
 		   (_convertTo.category() == Category::FixedBytes && 160 == dynamic_cast<FixedBytesType const&>(_convertTo).numBytes() * 8);
 }
 
 string AddressType::toString(bool) const
 {
+	if (m_stateMutability == StateMutability::Payable)
+		return "address payable";
+	else
+		return "address";
+}
+
+string AddressType::canonicalName() const
+{
 	return "address";
 }
 
@@ -479,17 +517,29 @@ TypePointer AddressType::binaryOperatorResult(Token::Value _operator, TypePointe
 	return Type::commonType(shared_from_this(), _other);
 }
 
+bool AddressType::operator==(Type const& _other) const
+{
+	if (_other.category() != category())
+		return false;
+	AddressType const& other = dynamic_cast<AddressType const&>(_other);
+	return other.m_stateMutability == m_stateMutability;
+}
+
 MemberList::MemberMap AddressType::nativeMembers(ContractDefinition const*) const
 {
-	return {
+	MemberList::MemberMap members = {
 		{"balance", make_shared<IntegerType>(256)},
 		{"call", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bool", "bytes memory"}, FunctionType::Kind::BareCall, false, StateMutability::Payable)},
 		{"callcode", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bool", "bytes memory"}, FunctionType::Kind::BareCallCode, false, StateMutability::Payable)},
 		{"delegatecall", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bool", "bytes memory"}, FunctionType::Kind::BareDelegateCall, false)},
-		{"send", make_shared<FunctionType>(strings{"uint"}, strings{"bool"}, FunctionType::Kind::Send)},
-		{"staticcall", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bool", "bytes memory"}, FunctionType::Kind::BareStaticCall, false, StateMutability::View)},
-		{"transfer", make_shared<FunctionType>(strings{"uint"}, strings(), FunctionType::Kind::Transfer)}
+		{"staticcall", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bool", "bytes memory"}, FunctionType::Kind::BareStaticCall, false, StateMutability::View)}
 	};
+	if (m_stateMutability == StateMutability::Payable)
+	{
+		members.emplace_back(MemberList::Member{"send", make_shared<FunctionType>(strings{"uint"}, strings{"bool"}, FunctionType::Kind::Send)});
+		members.emplace_back(MemberList::Member{"transfer", make_shared<FunctionType>(strings{"uint"}, strings(), FunctionType::Kind::Transfer)});
+	}
+	return members;
 }
 
 namespace
@@ -1476,7 +1526,9 @@ bool ContractType::isImplicitlyConvertibleTo(Type const& _convertTo) const
 
 bool ContractType::isExplicitlyConvertibleTo(Type const& _convertTo) const
 {
-	return isImplicitlyConvertibleTo(_convertTo) || _convertTo.category() == Category::Address;
+	if (auto const* addressType = dynamic_cast<AddressType const*>(&_convertTo))
+		return isPayable() || (addressType->stateMutability() < StateMutability::Payable);
+	return isImplicitlyConvertibleTo(_convertTo);
 }
 
 bool ContractType::isPayable() const
@@ -3275,7 +3327,7 @@ MemberList::MemberMap MagicType::nativeMembers(ContractDefinition const*) const
 	{
 	case Kind::Block:
 		return MemberList::MemberMap({
-			{"coinbase", make_shared<AddressType>()},
+			{"coinbase", make_shared<AddressType>(StateMutability::Payable)},
 			{"timestamp", make_shared<IntegerType>(256)},
 			{"blockhash", make_shared<FunctionType>(strings{"uint"}, strings{"bytes32"}, FunctionType::Kind::BlockHash, false, StateMutability::View)},
 			{"difficulty", make_shared<IntegerType>(256)},
@@ -3284,7 +3336,7 @@ MemberList::MemberMap MagicType::nativeMembers(ContractDefinition const*) const
 		});
 	case Kind::Message:
 		return MemberList::MemberMap({
-			{"sender", make_shared<AddressType>()},
+			{"sender", make_shared<AddressType>(StateMutability::Payable)},
 			{"gas", make_shared<IntegerType>(256)},
 			{"value", make_shared<IntegerType>(256)},
 			{"data", make_shared<ArrayType>(DataLocation::CallData)},
@@ -3292,7 +3344,7 @@ MemberList::MemberMap MagicType::nativeMembers(ContractDefinition const*) const
 		});
 	case Kind::Transaction:
 		return MemberList::MemberMap({
-			{"origin", make_shared<AddressType>()},
+			{"origin", make_shared<AddressType>(StateMutability::Payable)},
 			{"gasprice", make_shared<IntegerType>(256)}
 		});
 	case Kind::ABI:
diff --git a/libsolidity/ast/Types.h b/libsolidity/ast/Types.h
index 7ee66838..a2d18b0a 100644
--- a/libsolidity/ast/Types.h
+++ b/libsolidity/ast/Types.h
@@ -321,15 +321,16 @@ class AddressType: public Type
 public:
 	virtual Category category() const override { return Category::Address; }
 
-	explicit AddressType()
-	{
-	}
+	explicit AddressType(StateMutability _stateMutability);
 
 	virtual std::string richIdentifier() const override;
+	virtual bool isImplicitlyConvertibleTo(Type const& _other) const override;
 	virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
 	virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
 	virtual TypePointer binaryOperatorResult(Token::Value _operator, TypePointer const& _other) const override;
 
+	virtual bool operator==(Type const& _other) const override;
+
 	virtual unsigned calldataEncodedSize(bool _padded = true) const override { return _padded ? 32 : 160 / 8; }
 	virtual unsigned storageBytes() const override { return 160 / 8; }
 	virtual bool isValueType() const override { return true; }
@@ -337,11 +338,17 @@ public:
 	virtual MemberList::MemberMap nativeMembers(ContractDefinition const*) const override;
 
 	virtual std::string toString(bool _short) const override;
+	virtual std::string canonicalName() const override;
 
 	virtual u256 literalValue(Literal const* _literal) const override;
 
 	virtual TypePointer encodingType() const override { return shared_from_this(); }
 	virtual TypePointer interfaceType(bool) const override { return shared_from_this(); }
+
+	StateMutability stateMutability(void) const { return m_stateMutability; }
+
+private:
+	StateMutability m_stateMutability;
 };
 
 /**
@@ -755,7 +762,7 @@ public:
 	{
 		if (isSuper())
 			return TypePointer{};
-		return std::make_shared<AddressType>();
+		return std::make_shared<AddressType>(isPayable() ? StateMutability::Payable : StateMutability::NonPayable);
 	}
 	virtual TypePointer interfaceType(bool _inLibrary) const override
 	{
diff --git a/libsolidity/codegen/ABIFunctions.cpp b/libsolidity/codegen/ABIFunctions.cpp
index 5e5fe84a..6c27533c 100644
--- a/libsolidity/codegen/ABIFunctions.cpp
+++ b/libsolidity/codegen/ABIFunctions.cpp
@@ -242,8 +242,14 @@ string ABIFunctions::cleanupFunction(Type const& _type, bool _revertOnFailure)
 			break;
 		}
 		case Type::Category::Contract:
-			templ("body", "cleaned := " + cleanupFunction(AddressType()) + "(value)");
+		{
+			AddressType addressType(dynamic_cast<ContractType const&>(_type).isPayable() ?
+				StateMutability::Payable :
+				StateMutability::NonPayable
+			);
+			templ("body", "cleaned := " + cleanupFunction(addressType) + "(value)");
 			break;
+		}
 		case Type::Category::Enum:
 		{
 			size_t members = dynamic_cast<EnumType const&>(_type).numberOfMembers();
diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index 45e58bd0..bd863e05 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -1259,7 +1259,7 @@ bool ExpressionCompiler::visit(MemberAccess const& _memberAccess)
 				identifier = FunctionType(*function).externalIdentifier();
 			else
 				solAssert(false, "Contract member is neither variable nor function.");
-			utils().convertType(type, AddressType(), true);
+			utils().convertType(type, AddressType(type.isPayable() ? StateMutability::Payable : StateMutability::NonPayable), true);
 			m_context << identifier;
 		}
 		else
@@ -1277,15 +1277,24 @@ bool ExpressionCompiler::visit(MemberAccess const& _memberAccess)
 		{
 			utils().convertType(
 				*_memberAccess.expression().annotation().type,
-				AddressType(),
+				AddressType(StateMutability::NonPayable),
 				true
 			);
 			m_context << Instruction::BALANCE;
 		}
-		else if ((set<string>{"send", "transfer", "call", "callcode", "delegatecall", "staticcall"}).count(member))
+		else if ((set<string>{"send", "transfer"}).count(member))
+		{
+			solAssert(dynamic_cast<AddressType const&>(*_memberAccess.expression().annotation().type).stateMutability() == StateMutability::Payable, "");
+			utils().convertType(
+				*_memberAccess.expression().annotation().type,
+				AddressType(StateMutability::Payable),
+				true
+			);
+		}
+		else if ((set<string>{"call", "callcode", "delegatecall", "staticcall"}).count(member))
 			utils().convertType(
 				*_memberAccess.expression().annotation().type,
-				AddressType(),
+				AddressType(StateMutability::NonPayable),
 				true
 			);
 		else