Merge pull request #1264 from ethereum/988

State variable under contract's name

6 files changed, 150 insertions, 10 deletions

diff --git a/Changelog.md b/Changelog.md
index fdce077f..71c7a0fe 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -16,7 +16,8 @@ Bugfixes:
  * Type checker: fixed crash related to invalid literal numbers.
  * Type Checker: ``super.x`` does not look up ``x`` in the current contract.
  * Code generator: expect zero stack increase after ``super`` as an expression.
- * Code Generator: fixed an internal compiler error for ``L.Foo`` for ``enum Foo`` defined in library ``L``.
+ * Code Generator: fix an internal compiler error for ``L.Foo`` for ``enum Foo`` defined in library ``L``.
+ * Code generator: allow inheritance of ``enum`` definitions.
  * Inline assembly: support the ``address`` opcode.
  * Inline assembly: fix parsing of assignment after a label.
  * Inline assembly: external variables of unsupported type (such as ``this``, ``super``, etc.)
diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 10d24e5a..46f4f7f6 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -1386,6 +1386,11 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 	}
 	else if (exprType->category() == Type::Category::FixedBytes)
 		annotation.isLValue = false;
+	else if (TypeType const* typeType = dynamic_cast<decltype(typeType)>(exprType.get()))
+	{
+		if (ContractType const* contractType = dynamic_cast<decltype(contractType)>(typeType->actualType().get()))
+			annotation.isLValue = annotation.referencedDeclaration->isLValue();
+	}
 
 	return false;
 }
diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index 6d54b48b..9a096e2d 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -890,6 +890,8 @@ bool ExpressionCompiler::visit(MemberAccess const& _memberAccess)
 			{
 				// no-op
 			}
+			else if (auto variable = dynamic_cast<VariableDeclaration const*>(_memberAccess.annotation().referencedDeclaration))
+				appendVariable(*variable, static_cast<Expression const&>(_memberAccess));
 			else
 				_memberAccess.expression().accept(*this);
 		}
@@ -1203,15 +1205,7 @@ void ExpressionCompiler::endVisit(Identifier const& _identifier)
 	else if (FunctionDefinition const* functionDef = dynamic_cast<FunctionDefinition const*>(declaration))
 		m_context << m_context.virtualFunctionEntryLabel(*functionDef).pushTag();
 	else if (auto variable = dynamic_cast<VariableDeclaration const*>(declaration))
-	{
-		if (!variable->isConstant())
-			setLValueFromDeclaration(*declaration, _identifier);
-		else
-		{
-			variable->value()->accept(*this);
-			utils().convertType(*variable->value()->annotation().type, *variable->annotation().type);
-		}
-	}
+		appendVariable(*variable, static_cast<Expression const&>(_identifier));
 	else if (auto contract = dynamic_cast<ContractDefinition const*>(declaration))
 	{
 		if (contract->isLibrary())
@@ -1646,6 +1640,17 @@ void ExpressionCompiler::appendExpressionCopyToMemory(Type const& _expectedType,
 	utils().storeInMemoryDynamic(_expectedType);
 }
 
+void ExpressionCompiler::appendVariable(VariableDeclaration const& _variable, Expression const& _expression)
+{
+	if (!_variable.isConstant())
+		setLValueFromDeclaration(_variable, _expression);
+	else
+	{
+		_variable.value()->accept(*this);
+		utils().convertType(*_variable.value()->annotation().type, *_variable.annotation().type);
+	}
+}
+
 void ExpressionCompiler::setLValueFromDeclaration(Declaration const& _declaration, Expression const& _expression)
 {
 	if (m_context.isLocalVariable(&_declaration))
diff --git a/libsolidity/codegen/ExpressionCompiler.h b/libsolidity/codegen/ExpressionCompiler.h
index 43a92a10..f4ce1fec 100644
--- a/libsolidity/codegen/ExpressionCompiler.h
+++ b/libsolidity/codegen/ExpressionCompiler.h
@@ -103,6 +103,8 @@ private:
 	/// expected to be on the stack and is updated by this call.
 	void appendExpressionCopyToMemory(Type const& _expectedType, Expression const& _expression);
 
+	/// Appends code for a variable that might be a constant or not
+	void appendVariable(VariableDeclaration const& _variable, Expression const& _expression);
 	/// Sets the current LValue to a new one (of the appropriate type) from the given declaration.
 	/// Also retrieves the value if it was not requested by @a _expression.
 	void setLValueFromDeclaration(Declaration const& _declaration, Expression const& _expression);
diff --git a/test/libsolidity/SolidityEndToEndTest.cpp b/test/libsolidity/SolidityEndToEndTest.cpp
index bb197cca..8ef9a45b 100644
--- a/test/libsolidity/SolidityEndToEndTest.cpp
+++ b/test/libsolidity/SolidityEndToEndTest.cpp
@@ -5666,6 +5666,120 @@ BOOST_AUTO_TEST_CASE(accessor_for_const_state_variable)
 		BOOST_CHECK(callContractFunction("ticketPrice()") == encodeArgs(u256(555)));
 }
 
+BOOST_AUTO_TEST_CASE(state_variable_under_contract_name)
+{
+	char const* text = R"(
+		contract Scope {
+			uint stateVar = 42;
+
+			function getStateVar() constant returns (uint stateVar) {
+				stateVar = Scope.stateVar;
+			}
+		}
+	)";
+	compileAndRun(text);
+	BOOST_CHECK(callContractFunction("getStateVar()") == encodeArgs(u256(42)));
+}
+
+BOOST_AUTO_TEST_CASE(state_variable_local_variable_mixture)
+{
+	char const* sourceCode = R"(
+		contract A {
+			uint x = 1;
+			uint y = 2;
+			function a() returns (uint x) {
+				x = A.y;
+			}
+		}
+	)";
+
+	compileAndRun(sourceCode);
+	BOOST_CHECK(callContractFunction("a()") == encodeArgs(u256(2)));
+}
+
+BOOST_AUTO_TEST_CASE(inherited_function) {
+	char const* sourceCode = R"(
+		contract A { function f() internal returns (uint) { return 1; } }
+		contract B is A {
+			function f() internal returns (uint) { return 2; }
+			function g() returns (uint) {
+				return A.f();
+			}
+		}
+	)";
+
+	compileAndRun(sourceCode, 0, "B");
+	BOOST_CHECK(callContractFunction("g()") == encodeArgs(u256(1)));
+}
+
+BOOST_AUTO_TEST_CASE(inherited_function_from_a_library) {
+	char const* sourceCode = R"(
+		library A { function f() internal returns (uint) { return 1; } }
+		contract B {
+			function f() internal returns (uint) { return 2; }
+			function g() returns (uint) {
+				return A.f();
+			}
+		}
+	)";
+
+	compileAndRun(sourceCode, 0, "B");
+	BOOST_CHECK(callContractFunction("g()") == encodeArgs(u256(1)));
+}
+
+BOOST_AUTO_TEST_CASE(inherited_constant_state_var)
+{
+	char const* sourceCode = R"(
+		contract A {
+			uint constant x = 7;
+		}
+		contract B is A {
+			function f() returns (uint) {
+				return A.x;
+			}
+		}
+	)";
+
+	compileAndRun(sourceCode, 0, "B");
+	BOOST_CHECK(callContractFunction("f()") == encodeArgs(u256(7)));
+}
+
+BOOST_AUTO_TEST_CASE(multiple_inherited_state_vars)
+{
+	char const* sourceCode = R"(
+		contract A {
+			uint x = 7;
+		}
+		contract B {
+			uint x = 9;
+		}
+		contract C is A, B {
+			function a() returns (uint) {
+				return A.x;
+			}
+			function b() returns (uint) {
+				return B.x;
+			}
+			function a_set(uint _x) returns (uint) {
+				A.x = _x;
+				return 1;
+			}
+			function b_set(uint _x) returns (uint) {
+				B.x = _x;
+				return 1;
+			}
+		}
+	)";
+
+	compileAndRun(sourceCode, 0, "C");
+	BOOST_CHECK(callContractFunction("a()") == encodeArgs(u256(7)));
+	BOOST_CHECK(callContractFunction("b()") == encodeArgs(u256(9)));
+	BOOST_CHECK(callContractFunction("a_set(uint256)", u256(1)) == encodeArgs(u256(1)));
+	BOOST_CHECK(callContractFunction("b_set(uint256)", u256(3)) == encodeArgs(u256(1)));
+	BOOST_CHECK(callContractFunction("a()") == encodeArgs(u256(1)));
+	BOOST_CHECK(callContractFunction("b()") == encodeArgs(u256(3)));
+}
+
 BOOST_AUTO_TEST_CASE(constant_string_literal)
 {
 	char const* sourceCode = R"(
diff --git a/test/libsolidity/SolidityNameAndTypeResolution.cpp b/test/libsolidity/SolidityNameAndTypeResolution.cpp
index f7ac73ae..9fe91cca 100644
--- a/test/libsolidity/SolidityNameAndTypeResolution.cpp
+++ b/test/libsolidity/SolidityNameAndTypeResolution.cpp
@@ -1036,6 +1036,19 @@ BOOST_AUTO_TEST_CASE(private_state_variable)
 	BOOST_CHECK_MESSAGE(function == nullptr, "Accessor function of an internal variable should not exist");
 }
 
+BOOST_AUTO_TEST_CASE(missing_state_variable)
+{
+	char const* text = R"(
+		contract Scope {
+			function getStateVar() constant returns (uint stateVar) {
+				stateVar = Scope.stateVar; // should fail.
+			}
+		}
+	)";
+	BOOST_CHECK(expectError(text) == Error::Type::TypeError);
+}
+
+
 BOOST_AUTO_TEST_CASE(base_class_state_variable_accessor)
 {
 	// test for issue #1126 https://github.com/ethereum/cpp-ethereum/issues/1126