Merge pull request #665 from axic/feature/accept-ether

BREAKING: Add payable modifier

9 files changed, 133 insertions, 44 deletions

diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index bc03da01..06e26a76 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -272,6 +272,7 @@ void TypeChecker::checkContractIllegalOverrides(ContractDefinition const& _contr
 				if (
 					overriding->visibility() != function->visibility() ||
 					overriding->isDeclaredConst() != function->isDeclaredConst() ||
+					overriding->isPayable() != function->isPayable() ||
 					overridingType != functionType
 				)
 					typeError(overriding->location(), "Override changes extended function signature.");
@@ -348,7 +349,7 @@ void TypeChecker::endVisit(InheritanceSpecifier const& _inheritance)
 		typeError(_inheritance.location(), "Libraries cannot be inherited from.");
 
 	auto const& arguments = _inheritance.arguments();
-	TypePointers parameterTypes = ContractType(*base).constructorType()->parameterTypes();
+	TypePointers parameterTypes = ContractType(*base).newExpressionType()->parameterTypes();
 	if (!arguments.empty() && parameterTypes.size() != arguments.size())
 	{
 		typeError(
@@ -416,6 +417,15 @@ bool TypeChecker::visit(StructDefinition const& _struct)
 bool TypeChecker::visit(FunctionDefinition const& _function)
 {
 	bool isLibraryFunction = dynamic_cast<ContractDefinition const&>(*_function.scope()).isLibrary();
+	if (_function.isPayable())
+	{
+		if (isLibraryFunction)
+			typeError(_function.location(), "Library functions cannot be payable.");
+		if (!_function.isConstructor() && !_function.name().empty() && !_function.isPartOfExternalInterface())
+			typeError(_function.location(), "Internal functions cannot be payable.");
+		if (_function.isDeclaredConst())
+			typeError(_function.location(), "Functions cannot be constant and payable at the same time.");
+	}
 	for (ASTPointer<VariableDeclaration> const& var: _function.parameters() + _function.returnParameters())
 	{
 		if (!type(*var)->canLiveOutsideStorage())
@@ -1256,15 +1266,7 @@ void TypeChecker::endVisit(NewExpression const& _newExpression)
 				"Circular reference for contract creation (cannot create instance of derived or same contract)."
 			);
 
-		auto contractType = make_shared<ContractType>(*contract);
-		TypePointers parameterTypes = contractType->constructorType()->parameterTypes();
-		_newExpression.annotation().type = make_shared<FunctionType>(
-			parameterTypes,
-			TypePointers{contractType},
-			strings(),
-			strings(),
-			FunctionType::Location::Creation
-		);
+		_newExpression.annotation().type = FunctionType::newExpressionType(*contract);
 	}
 	else if (type->category() == Type::Category::Array)
 	{
@@ -1328,14 +1330,16 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 		fatalTypeError(
 			_memberAccess.location(),
 			"Member \"" + memberName + "\" not found or not visible "
-			"after argument-dependent lookup in " + exprType->toString()
+			"after argument-dependent lookup in " + exprType->toString() +
+			(memberName == "value" ? " - did you forget the \"payable\" modifier?" : "")
 		);
 	}
 	else if (possibleMembers.size() > 1)
 		fatalTypeError(
 			_memberAccess.location(),
 			"Member \"" + memberName + "\" not unique "
-			"after argument-dependent lookup in " + exprType->toString()
+			"after argument-dependent lookup in " + exprType->toString() +
+			(memberName == "value" ? " - did you forget the \"payable\" modifier?" : "")
 		);
 
 	auto& annotation = _memberAccess.annotation();
diff --git a/libsolidity/ast/AST.h b/libsolidity/ast/AST.h
index 761d85fe..8fd1584d 100644
--- a/libsolidity/ast/AST.h
+++ b/libsolidity/ast/AST.h
@@ -540,6 +540,7 @@ public:
 		bool _isDeclaredConst,
 		std::vector<ASTPointer<ModifierInvocation>> const& _modifiers,
 		ASTPointer<ParameterList> const& _returnParameters,
+		bool _isPayable,
 		ASTPointer<Block> const& _body
 	):
 		CallableDeclaration(_location, _name, _visibility, _parameters, _returnParameters),
@@ -547,6 +548,7 @@ public:
 		ImplementationOptional(_body != nullptr),
 		m_isConstructor(_isConstructor),
 		m_isDeclaredConst(_isDeclaredConst),
+		m_isPayable(_isPayable),
 		m_functionModifiers(_modifiers),
 		m_body(_body)
 	{}
@@ -556,6 +558,7 @@ public:
 
 	bool isConstructor() const { return m_isConstructor; }
 	bool isDeclaredConst() const { return m_isDeclaredConst; }
+	bool isPayable() const { return m_isPayable; }
 	std::vector<ASTPointer<ModifierInvocation>> const& modifiers() const { return m_functionModifiers; }
 	std::vector<ASTPointer<VariableDeclaration>> const& returnParameters() const { return m_returnParameters->parameters(); }
 	Block const& body() const { return *m_body; }
@@ -578,6 +581,7 @@ public:
 private:
 	bool m_isConstructor;
 	bool m_isDeclaredConst;
+	bool m_isPayable;
 	std::vector<ASTPointer<ModifierInvocation>> m_functionModifiers;
 	ASTPointer<Block> m_body;
 };
diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index d86a2caf..a0c1626d 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -362,8 +362,8 @@ MemberList::MemberMap IntegerType::nativeMembers(ContractDefinition const*) cons
 	if (isAddress())
 		return {
 			{"balance", make_shared<IntegerType >(256)},
-			{"call", make_shared<FunctionType>(strings(), strings{"bool"}, FunctionType::Location::Bare, true)},
-			{"callcode", make_shared<FunctionType>(strings(), strings{"bool"}, FunctionType::Location::BareCallCode, true)},
+			{"call", make_shared<FunctionType>(strings(), strings{"bool"}, FunctionType::Location::Bare, true, false, true)},
+			{"callcode", make_shared<FunctionType>(strings(), strings{"bool"}, FunctionType::Location::BareCallCode, true, false, true)},
 			{"delegatecall", make_shared<FunctionType>(strings(), strings{"bool"}, FunctionType::Location::BareDelegateCall, true)},
 			{"send", make_shared<FunctionType>(strings{"uint"}, strings{"bool"}, FunctionType::Location::Send)}
 		};
@@ -1329,16 +1329,10 @@ MemberList::MemberMap ContractType::nativeMembers(ContractDefinition const*) con
 	return members;
 }
 
-shared_ptr<FunctionType const> const& ContractType::constructorType() const
+shared_ptr<FunctionType const> const& ContractType::newExpressionType() const
 {
 	if (!m_constructorType)
-	{
-		FunctionDefinition const* constructor = m_contract.constructor();
-		if (constructor)
-			m_constructorType = make_shared<FunctionType>(*constructor);
-		else
-			m_constructorType = make_shared<FunctionType>(TypePointers(), TypePointers());
-	}
+		m_constructorType = FunctionType::newExpressionType(m_contract);
 	return m_constructorType;
 }
 
@@ -1653,6 +1647,7 @@ TypePointer TupleType::closestTemporaryType(TypePointer const& _targetType) cons
 FunctionType::FunctionType(FunctionDefinition const& _function, bool _isInternal):
 	m_location(_isInternal ? Location::Internal : Location::External),
 	m_isConstant(_function.isDeclaredConst()),
+	m_isPayable(_function.isPayable()),
 	m_declaration(&_function)
 {
 	TypePointers params;
@@ -1737,7 +1732,7 @@ FunctionType::FunctionType(VariableDeclaration const& _varDecl):
 	swap(retParamNames, m_returnParameterNames);
 }
 
-FunctionType::FunctionType(const EventDefinition& _event):
+FunctionType::FunctionType(EventDefinition const& _event):
 	m_location(Location::Event), m_isConstant(true), m_declaration(&_event)
 {
 	TypePointers params;
@@ -1753,6 +1748,35 @@ FunctionType::FunctionType(const EventDefinition& _event):
 	swap(paramNames, m_parameterNames);
 }
 
+FunctionTypePointer FunctionType::newExpressionType(ContractDefinition const& _contract)
+{
+	FunctionDefinition const* constructor = _contract.constructor();
+	TypePointers parameters;
+	strings parameterNames;
+	bool payable = false;
+
+	if (constructor)
+	{
+		for (ASTPointer<VariableDeclaration> const& var: constructor->parameters())
+		{
+			parameterNames.push_back(var->name());
+			parameters.push_back(var->annotation().type);
+		}
+		payable = constructor->isPayable();
+	}
+	return make_shared<FunctionType>(
+		parameters,
+		TypePointers{make_shared<ContractType>(_contract)},
+		parameterNames,
+		strings{""},
+		Location::Creation,
+		false,
+		nullptr,
+		false,
+		payable
+	);
+}
+
 vector<string> FunctionType::parameterNames() const
 {
 	if (!bound())
@@ -1871,7 +1895,12 @@ FunctionTypePointer FunctionType::interfaceFunctionType() const
 	if (variable && retParamTypes.empty())
 		return FunctionTypePointer();
 
-	return make_shared<FunctionType>(paramTypes, retParamTypes, m_parameterNames, m_returnParameterNames, m_location, m_arbitraryParameters);
+	return make_shared<FunctionType>(
+		paramTypes, retParamTypes,
+		m_parameterNames, m_returnParameterNames,
+		m_location, m_arbitraryParameters,
+		m_declaration, m_isConstant, m_isPayable
+	);
 }
 
 MemberList::MemberMap FunctionType::nativeMembers(ContractDefinition const*) const
@@ -1889,20 +1918,25 @@ MemberList::MemberMap FunctionType::nativeMembers(ContractDefinition const*) con
 	{
 		MemberList::MemberMap members;
 		if (m_location != Location::BareDelegateCall && m_location != Location::DelegateCall)
-			members.push_back(MemberList::Member(
-				"value",
-				make_shared<FunctionType>(
-					parseElementaryTypeVector({"uint"}),
-					TypePointers{copyAndSetGasOrValue(false, true)},
-					strings(),
-					strings(),
-					Location::SetValue,
-					false,
-					nullptr,
-					m_gasSet,
-					m_valueSet
-				)
-			));
+		{
+			if (m_isPayable)
+				members.push_back(MemberList::Member(
+					"value",
+					make_shared<FunctionType>(
+						parseElementaryTypeVector({"uint"}),
+						TypePointers{copyAndSetGasOrValue(false, true)},
+						strings(),
+						strings(),
+						Location::SetValue,
+						false,
+						nullptr,
+						false,
+						false,
+						m_gasSet,
+						m_valueSet
+					)
+				));
+		}
 		if (m_location != Location::Creation)
 			members.push_back(MemberList::Member(
 				"gas",
@@ -1914,6 +1948,8 @@ MemberList::MemberMap FunctionType::nativeMembers(ContractDefinition const*) con
 					Location::SetGas,
 					false,
 					nullptr,
+					false,
+					false,
 					m_gasSet,
 					m_valueSet
 				)
@@ -2019,6 +2055,8 @@ TypePointer FunctionType::copyAndSetGasOrValue(bool _setGas, bool _setValue) con
 		m_location,
 		m_arbitraryParameters,
 		m_declaration,
+		m_isConstant,
+		m_isPayable,
 		m_gasSet || _setGas,
 		m_valueSet || _setValue,
 		m_bound
@@ -2064,6 +2102,8 @@ FunctionTypePointer FunctionType::asMemberFunction(bool _inLibrary, bool _bound)
 		location,
 		m_arbitraryParameters,
 		m_declaration,
+		m_isConstant,
+		m_isPayable,
 		m_gasSet,
 		m_valueSet,
 		_bound
diff --git a/libsolidity/ast/Types.h b/libsolidity/ast/Types.h
index 1282e5d8..9173f39a 100644
--- a/libsolidity/ast/Types.h
+++ b/libsolidity/ast/Types.h
@@ -640,9 +640,8 @@ public:
 	bool isSuper() const { return m_super; }
 	ContractDefinition const& contractDefinition() const { return m_contract; }
 
-	/// Returns the function type of the constructor. Note that the location part of the function type
-	/// is not used, as this type cannot be the type of a variable or expression.
-	FunctionTypePointer const& constructorType() const;
+	/// Returns the function type of the constructor modified to return an object of the contract's type.
+	FunctionTypePointer const& newExpressionType() const;
 
 	/// @returns the identifier of the function with the given name or Invalid256 if such a name does
 	/// not exist.
@@ -820,21 +819,32 @@ public:
 	explicit FunctionType(VariableDeclaration const& _varDecl);
 	/// Creates the function type of an event.
 	explicit FunctionType(EventDefinition const& _event);
+	/// Function type constructor to be used for a plain type (not derived from a declaration).
 	FunctionType(
 		strings const& _parameterTypes,
 		strings const& _returnParameterTypes,
 		Location _location = Location::Internal,
-		bool _arbitraryParameters = false
+		bool _arbitraryParameters = false,
+		bool _constant = false,
+		bool _payable = false
 	): FunctionType(
 		parseElementaryTypeVector(_parameterTypes),
 		parseElementaryTypeVector(_returnParameterTypes),
 		strings(),
 		strings(),
 		_location,
-		_arbitraryParameters
+		_arbitraryParameters,
+		nullptr,
+		_constant,
+		_payable
 	)
 	{
 	}
+
+	/// @returns the type of the "new Contract" function, i.e. basically the constructor.
+	static FunctionTypePointer newExpressionType(ContractDefinition const& _contract);
+
+	/// Detailed constructor, use with care.
 	FunctionType(
 		TypePointers const& _parameterTypes,
 		TypePointers const& _returnParameterTypes,
@@ -843,6 +853,8 @@ public:
 		Location _location = Location::Internal,
 		bool _arbitraryParameters = false,
 		Declaration const* _declaration = nullptr,
+		bool _isConstant = false,
+		bool _isPayable = false,
 		bool _gasSet = false,
 		bool _valueSet = false,
 		bool _bound = false
@@ -856,6 +868,8 @@ public:
 		m_gasSet(_gasSet),
 		m_valueSet(_valueSet),
 		m_bound(_bound),
+		m_isConstant(_isConstant),
+		m_isPayable(_isPayable),
 		m_declaration(_declaration)
 	{}
 
@@ -905,6 +919,7 @@ public:
 	}
 	bool hasDeclaration() const { return !!m_declaration; }
 	bool isConstant() const { return m_isConstant; }
+	bool isPayable() const { return m_isPayable; }
 	/// @return A shared pointer of an ASTString.
 	/// Can contain a nullptr in which case indicates absence of documentation
 	ASTPointer<ASTString> documentation() const;
@@ -942,6 +957,7 @@ private:
 	bool const m_valueSet = false; ///< true iff the value to be sent is on the stack
 	bool const m_bound = false; ///< true iff the function is called as arg1.fun(arg2, ..., argn)
 	bool m_isConstant = false;
+	bool m_isPayable = false;
 	Declaration const* m_declaration = nullptr;
 };
 
diff --git a/libsolidity/codegen/ContractCompiler.cpp b/libsolidity/codegen/ContractCompiler.cpp
index 9d77ccdc..33571bc0 100644
--- a/libsolidity/codegen/ContractCompiler.cpp
+++ b/libsolidity/codegen/ContractCompiler.cpp
@@ -242,6 +242,12 @@ void ContractCompiler::appendFunctionSelector(ContractDefinition const& _contrac
 	m_context << notFound;
 	if (fallback)
 	{
+		if (!fallback->isPayable())
+		{
+			// Throw if function is not payable but call contained ether.
+			m_context << Instruction::CALLVALUE;
+			m_context.appendConditionalJumpTo(m_context.errorTag());
+		}
 		eth::AssemblyItem returnTag = m_context.pushNewTag();
 		fallback->accept(*this);
 		m_context << returnTag;
@@ -255,7 +261,15 @@ void ContractCompiler::appendFunctionSelector(ContractDefinition const& _contrac
 		FunctionTypePointer const& functionType = it.second;
 		solAssert(functionType->hasDeclaration(), "");
 		CompilerContext::LocationSetter locationSetter(m_context, functionType->declaration());
+
 		m_context << callDataUnpackerEntryPoints.at(it.first);
+		if (!functionType->isPayable())
+		{
+			// Throw if function is not payable but call contained ether.
+			m_context << Instruction::CALLVALUE;
+			m_context.appendConditionalJumpTo(m_context.errorTag());
+		}
+
 		eth::AssemblyItem returnTag = m_context.pushNewTag();
 		m_context << CompilerUtils::dataStartOffset;
 		appendCalldataUnpacker(functionType->parameterTypes());
diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index 7b6aa50a..1cc4a50d 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -583,6 +583,8 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 					Location::Bare,
 					false,
 					nullptr,
+					false,
+					false,
 					true,
 					true
 				),
diff --git a/libsolidity/interface/InterfaceHandler.cpp b/libsolidity/interface/InterfaceHandler.cpp
index d39f8285..6e3ae78f 100644
--- a/libsolidity/interface/InterfaceHandler.cpp
+++ b/libsolidity/interface/InterfaceHandler.cpp
@@ -52,6 +52,7 @@ string InterfaceHandler::abiInterface(ContractDefinition const& _contractDef)
 		method["type"] = "function";
 		method["name"] = it.second->declaration().name();
 		method["constant"] = it.second->isConstant();
+		method["payable"] = it.second->isPayable();
 		method["inputs"] = populateParameters(
 			externalFunctionType->parameterNames(),
 			externalFunctionType->parameterTypeNames(_contractDef.isLibrary())
@@ -81,6 +82,7 @@ string InterfaceHandler::abiInterface(ContractDefinition const& _contractDef)
 		Json::Value method;
 		method["type"] = "fallback";
 		method["constant"] = externalFunctionType->isConstant();
+		method["payable"] = externalFunctionType->isPayable();
 		abi.append(method);
 	}
 	for (auto const& it: _contractDef.interfaceEvents())
diff --git a/libsolidity/parsing/Parser.cpp b/libsolidity/parsing/Parser.cpp
index 1bffa5d7..0e99d1e7 100644
--- a/libsolidity/parsing/Parser.cpp
+++ b/libsolidity/parsing/Parser.cpp
@@ -305,6 +305,7 @@ ASTPointer<FunctionDefinition> Parser::parseFunctionDefinition(ASTString const*
 	options.allowLocationSpecifier = true;
 	ASTPointer<ParameterList> parameters(parseParameterList(options));
 	bool isDeclaredConst = false;
+	bool isPayable = false;
 	Declaration::Visibility visibility(Declaration::Visibility::Default);
 	vector<ASTPointer<ModifierInvocation>> modifiers;
 	while (true)
@@ -315,6 +316,11 @@ ASTPointer<FunctionDefinition> Parser::parseFunctionDefinition(ASTString const*
 			isDeclaredConst = true;
 			m_scanner->next();
 		}
+		else if (m_scanner->currentToken() == Token::Payable)
+		{
+			isPayable = true;
+			m_scanner->next();
+		}
 		else if (token == Token::Identifier)
 			modifiers.push_back(parseModifierInvocation());
 		else if (Token::isVisibilitySpecifier(token))
@@ -354,6 +360,7 @@ ASTPointer<FunctionDefinition> Parser::parseFunctionDefinition(ASTString const*
 		isDeclaredConst,
 		modifiers,
 		returnParameters,
+		isPayable,
 		block
 	);
 }
diff --git a/libsolidity/parsing/Token.h b/libsolidity/parsing/Token.h
index 15d4860f..cc85b610 100644
--- a/libsolidity/parsing/Token.h
+++ b/libsolidity/parsing/Token.h
@@ -166,6 +166,7 @@ namespace solidity
 	K(Memory, "memory", 0)                                             \
 	K(Modifier, "modifier", 0)                                         \
 	K(New, "new", 0)                                                   \
+	K(Payable, "payable", 0)                                           \
 	K(Public, "public", 0)                                             \
 	K(Pragma, "pragma", 0)                                             \
 	K(Private, "private", 0)                                           \
@@ -229,7 +230,6 @@ namespace solidity
 	K(Let, "let", 0)                                                   \
 	K(Match, "match", 0)                                               \
 	K(Of, "of", 0)                                                     \
-	K(Payable, "payable", 0)                                           \
 	K(Relocatable, "relocatable", 0)                                   \
 	K(Static, "static", 0)                                             \
 	K(Switch, "switch", 0)                                             \