Enum type conversion and member value access.

- Added tests for the type conversion part.

- Enum member value access still needs some work

libsolidity/AST.cpp

@@ -277,6 +277,19 @@ TypePointer EnumDefinition::getType(ContractDefinition const*) const
 	return make_shared<TypeType>(make_shared<EnumType>(*this));
 }
 
+
+unsigned int EnumDefinition::getMemberValue(ASTString const& _member) const
+{
+	unsigned int index = 0;
+	for (ASTPointer<EnumDeclaration> const& decl: m_members)
+	{
+		if (decl->getName() == _member)
+			return index;
+		++index;
+	}
+	BOOST_THROW_EXCEPTION(createTypeError("Requested unknown enum value ." + _member));
+}
+
 TypePointer FunctionDefinition::getType(ContractDefinition const*) const
 {
 	return make_shared<FunctionType>(*this);

libsolidity/AST.h

@@ -348,6 +348,9 @@ public:
 
 	virtual TypePointer getType(ContractDefinition const*) const override;
 
+	/// @returns the value that the string has in the Enum
+	unsigned int getMemberValue(ASTString const& _member) const;
+
 	/// Checks that the members do not include any duplicate names
 	void checkValidityOfMembers() const;
 

libsolidity/ExpressionCompiler.cpp

@@ -489,6 +489,12 @@ void ExpressionCompiler::endVisit(MemberAccess const& _memberAccess)
 		m_currentLValue.retrieveValueIfLValueNotRequested(_memberAccess);
 		break;
 	}
+	case Type::Category::Enum:
+	{
+		EnumType const& type = dynamic_cast<EnumType const&>(*_memberAccess.getExpression().getType());
+		EnumDefinition const& enumDef = type.getEnumDefinition();
+		m_context << enumDef.getMemberValue(_memberAccess.getMemberName());
+	}
 	case Type::Category::TypeType:
 	{
 		TypeType const& type = dynamic_cast<TypeType const&>(*_memberAccess.getExpression().getType());
@@ -562,6 +568,10 @@ void ExpressionCompiler::endVisit(Identifier const& _identifier)
 	{
 		// no-op
 	}
+	else if (dynamic_cast<EnumDefinition const*>(declaration))
+	{
+		// no-op
+	}
 	else
 	{
 		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Identifier type not expected in expression context."));
@@ -746,7 +756,7 @@ void ExpressionCompiler::appendTypeConversion(Type const& _typeOnStack, Type con
 		}
 	}
 	else if (stackTypeCategory == Type::Category::Integer || stackTypeCategory == Type::Category::Contract ||
-			 stackTypeCategory == Type::Category::IntegerConstant)
+			 stackTypeCategory == Type::Category::IntegerConstant || stackTypeCategory == Type::Category::Enum)
 	{
 		if (targetTypeCategory == Type::Category::String && stackTypeCategory == Type::Category::Integer)
 		{

libsolidity/Types.cpp

@@ -682,6 +682,11 @@ string EnumType::toString() const
 	return string("enum ") + m_enum.getName();
 }
 
+bool EnumType::isExplicitlyConvertibleTo(Type const& _convertTo) const
+{
+	return _convertTo.getCategory() == getCategory() || _convertTo.getCategory() == Category::Integer;
+}
+
 FunctionType::FunctionType(FunctionDefinition const& _function, bool _isInternal):
 	m_location(_isInternal ? Location::Internal : Location::External),
 	m_isConstant(_function.isDeclaredConst()),

libsolidity/Types.h

@@ -381,6 +381,8 @@ public:
 	virtual std::string toString() const override;
 	virtual bool isValueType() const override { return true; }
 
+	virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
+
 	EnumDefinition const& getEnumDefinition() const { return m_enum; }
 
 private:

test/SolidityEndToEndTest.cpp

@@ -2510,7 +2510,7 @@ BOOST_AUTO_TEST_CASE(using_enums)
 				}
 				function getChoice() returns (uint d)
 				{
-					d = choices;
+					d = uint256(choices);
 				}
 				ActionChoices choices;
 			}

test/SolidityNameAndTypeResolution.cpp

@@ -1022,6 +1022,40 @@ BOOST_AUTO_TEST_CASE(enum_invalid_member_access)
 	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
 }
 
+BOOST_AUTO_TEST_CASE(enum_explicit_conversion_is_okay)
+{
+	char const* text = R"(
+			contract test {
+				enum ActionChoices { GoLeft, GoRight, GoStraight, Sit };
+				function test()
+				{
+					a = uint256(ActionChoices.GoStraight);
+					b = uint64(ActionChoices.Sit);
+				}
+				uint256 a;
+				uint64 b;
+			}
+	)";
+	BOOST_CHECK_NO_THROW(parseTextAndResolveNamesWithChecks(text));
+}
+
+BOOST_AUTO_TEST_CASE(enum_implicit_conversion_is_not_okay)
+{
+	char const* text = R"(
+			contract test {
+				enum ActionChoices { GoLeft, GoRight, GoStraight, Sit };
+				function test()
+				{
+					a = ActionChoices.GoStraight;
+					b = ActionChoices.Sit;
+				}
+				uint256 a;
+				uint64 b;
+			}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 }