Struct types.

7 files changed, 126 insertions, 20 deletions

diff --git a/AST.cpp b/AST.cpp
index d5f856df..e8bdecf3 100644
--- a/AST.cpp
+++ b/AST.cpp
@@ -460,8 +460,17 @@ bool FunctionCall::isTypeConversion() const
 
 void MemberAccess::checkTypeRequirements()
 {
-	BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Member access not yet implemented."));
-	// m_type = ;
+	m_expression->checkTypeRequirements();
+	m_expression->requireLValue();
+	if (m_expression->getType()->getCategory() != Type::Category::STRUCT)
+		BOOST_THROW_EXCEPTION(createTypeError("Member access to a non-struct (is " +
+													  m_expression->getType()->toString() + ")"));
+	StructType const& type = dynamic_cast<StructType const&>(*m_expression->getType());
+	unsigned memberIndex = type.memberNameToIndex(*m_memberName);
+	if (memberIndex >= type.getMemberCount())
+		BOOST_THROW_EXCEPTION(createTypeError("Member \"" + *m_memberName + "\" not found in " + type.toString()));
+	m_type = type.getMemberByIndex(memberIndex).getType();
+	m_isLvalue = true;
 }
 
 void IndexAccess::checkTypeRequirements()
diff --git a/AST.h b/AST.h
index 31ca56f7..80c7dd19 100644
--- a/AST.h
+++ b/AST.h
@@ -146,7 +146,7 @@ private:
 /**
  * Parameter list, used as function parameter list and return list.
  * None of the parameters is allowed to contain mappings (not even recursively
- * inside structs), but (@todo) this is not yet enforced.
+ * inside structs).
  */
 class ParameterList: public ASTNode
 {
@@ -368,7 +368,6 @@ private:
 
 /**
  * Statement in which a break statement is legal.
- * @todo actually check this requirement.
  */
 class BreakableStatement: public Statement
 {
@@ -629,6 +628,7 @@ public:
 				 ASTPointer<ASTString> const& _memberName):
 		Expression(_location), m_expression(_expression), m_memberName(_memberName) {}
 	virtual void accept(ASTVisitor& _visitor) override;
+	Expression& getExpression() const { return *m_expression; }
 	ASTString const& getMemberName() const { return *m_memberName; }
 	virtual void checkTypeRequirements() override;
 
@@ -651,6 +651,7 @@ public:
 
 	Expression& getBaseExpression() const { return *m_base; }
 	Expression& getIndexExpression() const { return *m_index; }
+
 private:
 	ASTPointer<Expression> m_base;
 	ASTPointer<Expression> m_index;
diff --git a/ExpressionCompiler.cpp b/ExpressionCompiler.cpp
index d80b42b3..f37ce39c 100644
--- a/ExpressionCompiler.cpp
+++ b/ExpressionCompiler.cpp
@@ -49,7 +49,6 @@ bool ExpressionCompiler::visit(Assignment& _assignment)
 {
 	_assignment.getRightHandSide().accept(*this);
 	appendTypeConversion(*_assignment.getRightHandSide().getType(), *_assignment.getType());
-	m_currentLValue.reset();
 	_assignment.getLeftHandSide().accept(*this);
 	if (asserts(m_currentLValue.isValid()))
 		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("LValue not retrieved."));
@@ -63,6 +62,7 @@ bool ExpressionCompiler::visit(Assignment& _assignment)
 		appendOrdinaryBinaryOperatorCode(Token::AssignmentToBinaryOp(op), *_assignment.getType());
 	}
 	m_currentLValue.storeValue(_assignment);
+	m_currentLValue.reset();
 
 	return false;
 }
@@ -90,6 +90,7 @@ void ExpressionCompiler::endVisit(UnaryOperation& _unaryOperation)
 		if (m_currentLValue.storesReferenceOnStack())
 			m_context << eth::Instruction::SWAP1;
 		m_currentLValue.storeValue(_unaryOperation);
+		m_currentLValue.reset();
 		break;
 	case Token::INC: // ++ (pre- or postfix)
 	case Token::DEC: // -- (pre- or postfix)
@@ -113,6 +114,7 @@ void ExpressionCompiler::endVisit(UnaryOperation& _unaryOperation)
 		if (m_currentLValue.storesReferenceOnStack())
 			m_context << eth::Instruction::SWAP1;
 		m_currentLValue.storeValue(_unaryOperation, !_unaryOperation.isPrefixOperation());
+		m_currentLValue.reset();
 		break;
 	case Token::ADD: // +
 		// unary add, so basically no-op
@@ -182,10 +184,10 @@ bool ExpressionCompiler::visit(FunctionCall& _functionCall)
 			arguments[i]->accept(*this);
 			appendTypeConversion(*arguments[i]->getType(), *function.getParameters()[i]->getType());
 		}
-		m_currentLValue.reset();
 		_functionCall.getExpression().accept(*this);
 		if (asserts(m_currentLValue.isInCode()))
 			BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Code reference expected."));
+		m_currentLValue.reset();
 
 		m_context.appendJump();
 		m_context << returnLabel;
@@ -201,9 +203,16 @@ bool ExpressionCompiler::visit(FunctionCall& _functionCall)
 	return false;
 }
 
-void ExpressionCompiler::endVisit(MemberAccess&)
+void ExpressionCompiler::endVisit(MemberAccess& _memberAccess)
 {
-	BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Member access not yet implemented."));
+	if (asserts(m_currentLValue.isInStorage()))
+		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Member access to a non-storage value."));
+	StructType const& type = dynamic_cast<StructType const&>(*_memberAccess.getExpression().getType());
+	unsigned memberIndex = type.memberNameToIndex(_memberAccess.getMemberName());
+	if (asserts(memberIndex <= type.getMemberCount()))
+		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Member not found in struct during compilation."));
+	m_context << type.getStorageOffsetOfMember(memberIndex) << eth::Instruction::ADD;
+	m_currentLValue.retrieveValueIfLValueNotRequested(_memberAccess);
 }
 
 bool ExpressionCompiler::visit(IndexAccess& _indexAccess)
diff --git a/NameAndTypeResolver.cpp b/NameAndTypeResolver.cpp
index 4a15fe79..5bc40685 100644
--- a/NameAndTypeResolver.cpp
+++ b/NameAndTypeResolver.cpp
@@ -37,7 +37,10 @@ void NameAndTypeResolver::resolveNamesAndTypes(ContractDefinition& _contract)
 	reset();
 	DeclarationRegistrationHelper registrar(m_scopes, _contract);
 	m_currentScope = &m_scopes[&_contract];
-	//@todo structs
+	for (ASTPointer<StructDefinition> const& structDef: _contract.getDefinedStructs())
+		ReferencesResolver resolver(*structDef, *this, nullptr);
+	for (ASTPointer<StructDefinition> const& structDef: _contract.getDefinedStructs())
+		checkForRecursion(*structDef);
 	for (ASTPointer<VariableDeclaration> const& variable: _contract.getStateVariables())
 		ReferencesResolver resolver(*variable, *this, nullptr);
 	for (ASTPointer<FunctionDefinition> const& function: _contract.getDefinedFunctions())
@@ -70,6 +73,24 @@ Declaration* NameAndTypeResolver::getNameFromCurrentScope(ASTString const& _name
 	return m_currentScope->resolveName(_name, _recursive);
 }
 
+void NameAndTypeResolver::checkForRecursion(StructDefinition const& _struct)
+{
+	set<StructDefinition const*> definitionsSeen;
+	vector<StructDefinition const*> queue = {&_struct};
+	while (!queue.empty())
+	{
+		StructDefinition const* def = queue.back();
+		queue.pop_back();
+		if (definitionsSeen.count(def))
+			BOOST_THROW_EXCEPTION(ParserError() << errinfo_sourceLocation(def->getLocation())
+												<< errinfo_comment("Recursive struct definition."));
+		definitionsSeen.insert(def);
+		for (ASTPointer<VariableDeclaration> const& member: def->getMembers())
+			if (member->getType()->getCategory() == Type::Category::STRUCT)
+				queue.push_back(dynamic_cast<UserDefinedTypeName&>(*member->getTypeName()).getReferencedStruct());
+	}
+}
+
 void NameAndTypeResolver::reset()
 {
 	m_scopes.clear();
@@ -163,8 +184,8 @@ void DeclarationRegistrationHelper::registerDeclaration(Declaration& _declaratio
 }
 
 ReferencesResolver::ReferencesResolver(ASTNode& _root, NameAndTypeResolver& _resolver,
-									   ParameterList* _returnParameters):
-	m_resolver(_resolver), m_returnParameters(_returnParameters)
+									   ParameterList* _returnParameters, bool _allowLazyTypes):
+	m_resolver(_resolver), m_returnParameters(_returnParameters), m_allowLazyTypes(_allowLazyTypes)
 {
 	_root.accept(*this);
 }
@@ -175,6 +196,8 @@ void ReferencesResolver::endVisit(VariableDeclaration& _variable)
 	// or mapping
 	if (_variable.getTypeName())
 		_variable.setType(_variable.getTypeName()->toType());
+	else if (!m_allowLazyTypes)
+		BOOST_THROW_EXCEPTION(_variable.createTypeError("Explicit type needed."));
 	// otherwise we have a "var"-declaration whose type is resolved by the first assignment
 }
 
diff --git a/NameAndTypeResolver.h b/NameAndTypeResolver.h
index 90902494..d335807e 100644
--- a/NameAndTypeResolver.h
+++ b/NameAndTypeResolver.h
@@ -55,10 +55,13 @@ public:
 	Declaration* getNameFromCurrentScope(ASTString const& _name, bool _recursive = true);
 
 private:
+	/// Throws if @a _struct contains a recursive loop. Note that recursion via mappings is fine.
+	void checkForRecursion(StructDefinition const& _struct);
 	void reset();
 
-	/// Maps nodes declaring a scope to scopes, i.e. ContractDefinition, FunctionDeclaration and
-	/// StructDefinition (@todo not yet implemented), where nullptr denotes the global scope.
+	/// Maps nodes declaring a scope to scopes, i.e. ContractDefinition and FunctionDeclaration,
+	/// where nullptr denotes the global scope. Note that structs are not scope since they do
+	/// not contain code.
 	std::map<ASTNode const*, Scope> m_scopes;
 
 	Scope* m_currentScope;
@@ -99,7 +102,8 @@ private:
 class ReferencesResolver: private ASTVisitor
 {
 public:
-	ReferencesResolver(ASTNode& _root, NameAndTypeResolver& _resolver, ParameterList* _returnParameters);
+	ReferencesResolver(ASTNode& _root, NameAndTypeResolver& _resolver,
+					   ParameterList* _returnParameters, bool _allowLazyTypes = true);
 
 private:
 	virtual void endVisit(VariableDeclaration& _variable) override;
@@ -110,6 +114,7 @@ private:
 
 	NameAndTypeResolver& m_resolver;
 	ParameterList* m_returnParameters;
+	bool m_allowLazyTypes;
 };
 
 }
diff --git a/Types.cpp b/Types.cpp
index e37ed3e5..63bad5d6 100644
--- a/Types.cpp
+++ b/Types.cpp
@@ -80,7 +80,7 @@ shared_ptr<Type> Type::forLiteral(Literal const& _literal)
 	case Token::NUMBER:
 		return IntegerType::smallestTypeForLiteral(_literal.getValue());
 	case Token::STRING_LITERAL:
-		return shared_ptr<Type>(); // @todo
+		return shared_ptr<Type>(); // @todo add string literals
 	default:
 		return shared_ptr<Type>();
 	}
@@ -231,6 +231,48 @@ u256 StructType::getStorageSize() const
 	return max<u256>(1, size);
 }
 
+bool StructType::canLiveOutsideStorage() const
+{
+	for (unsigned i = 0; i < getMemberCount(); ++i)
+		if (!getMemberByIndex(i).getType()->canLiveOutsideStorage())
+			return false;
+	return true;
+}
+
+string StructType::toString() const
+{
+	return string("struct ") + m_struct.getName();
+}
+
+unsigned StructType::getMemberCount() const
+{
+	return m_struct.getMembers().size();
+}
+
+unsigned StructType::memberNameToIndex(string const& _name) const
+{
+	vector<ASTPointer<VariableDeclaration>> const& members = m_struct.getMembers();
+	for (unsigned index = 0; index < members.size(); ++index)
+		if (members[index]->getName() == _name)
+			return index;
+	return unsigned(-1);
+}
+
+VariableDeclaration const& StructType::getMemberByIndex(unsigned _index) const
+{
+	return *m_struct.getMembers()[_index];
+}
+
+u256 StructType::getStorageOffsetOfMember(unsigned _index) const
+{
+	//@todo cache member offset?
+	u256 offset;
+	vector<ASTPointer<VariableDeclaration>> const& members = m_struct.getMembers();
+	for (unsigned index = 0; index < _index; ++index)
+		offset += getMemberByIndex(index).getType()->getStorageSize();
+	return offset;
+}
+
 bool FunctionType::operator==(Type const& _other) const
 {
 	if (_other.getCategory() != getCategory())
@@ -239,6 +281,12 @@ bool FunctionType::operator==(Type const& _other) const
 	return other.m_function == m_function;
 }
 
+string FunctionType::toString() const
+{
+	//@todo nice string for function types
+	return "function(...)returns(...)";
+}
+
 bool MappingType::operator==(Type const& _other) const
 {
 	if (_other.getCategory() != getCategory())
@@ -247,6 +295,11 @@ bool MappingType::operator==(Type const& _other) const
 	return *other.m_keyType == *m_keyType && *other.m_valueType == *m_valueType;
 }
 
+string MappingType::toString() const
+{
+	return "mapping(" + getKeyType()->toString() + " => " + getValueType()->toString() + ")";
+}
+
 bool TypeType::operator==(Type const& _other) const
 {
 	if (_other.getCategory() != getCategory())
diff --git a/Types.h b/Types.h
index b9bb74db..72647017 100644
--- a/Types.h
+++ b/Types.h
@@ -184,9 +184,14 @@ public:
 
 	virtual bool operator==(Type const& _other) const override;
 	virtual u256 getStorageSize() const;
-	//@todo it can, if its members can
-	virtual bool canLiveOutsideStorage() const { return false; }
-	virtual std::string toString() const override { return "struct{...}"; }
+	virtual bool canLiveOutsideStorage() const;
+	virtual std::string toString() const override;
+
+	unsigned getMemberCount() const;
+	/// Returns the index of the member with name @a _name or unsigned(-1) if it does not exist.
+	unsigned memberNameToIndex(std::string const& _name) const;
+	VariableDeclaration const& getMemberByIndex(unsigned _index) const;
+	u256 getStorageOffsetOfMember(unsigned _index) const;
 
 private:
 	StructDefinition const& m_struct;
@@ -204,7 +209,7 @@ public:
 	FunctionDefinition const& getFunction() const { return m_function; }
 
 	virtual bool operator==(Type const& _other) const override;
-	virtual std::string toString() const override { return "function(...)returns(...)"; }
+	virtual std::string toString() const override;
 	virtual u256 getStorageSize() const { BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Storage size of non-storable function type requested.")); }
 	virtual bool canLiveOutsideStorage() const { return false; }
 
@@ -223,11 +228,12 @@ public:
 		m_keyType(_keyType), m_valueType(_valueType) {}
 
 	virtual bool operator==(Type const& _other) const override;
-	virtual std::string toString() const override { return "mapping(...=>...)"; }
+	virtual std::string toString() const override;
 	virtual bool canLiveOutsideStorage() const { return false; }
 
 	std::shared_ptr<Type const> getKeyType() const { return m_keyType; }
 	std::shared_ptr<Type const> getValueType() const { return m_valueType; }
+
 private:
 	std::shared_ptr<Type const> m_keyType;
 	std::shared_ptr<Type const> m_valueType;