From 3bc78361d6923614b33728d287bf9822aa109a04 Mon Sep 17 00:00:00 2001
From: chriseth <c@ethdev.com>
Date: Thu, 16 Apr 2015 00:06:57 +0200
Subject: [PATCH] Bugfixes concerning variable declarations.

Fixes #1637
---
 libsolidity/AST.cpp                    | 16 +++++++---------
 libsolidity/Parser.cpp                 | 23 ++++++++++++-----------
 test/SolidityNameAndTypeResolution.cpp | 12 +++++++++++-
 test/SolidityParser.cpp                |  9 +++++++++
 4 files changed, 39 insertions(+), 21 deletions(-)

diff --git a/libsolidity/AST.cpp b/libsolidity/AST.cpp
index 095ba7bf1..0abdf7819 100644
--- a/libsolidity/AST.cpp
+++ b/libsolidity/AST.cpp
@@ -378,20 +378,16 @@ void VariableDeclaration::checkTypeRequirements()
 		if ((m_type && !m_type->isValueType()) || !m_value)
 			BOOST_THROW_EXCEPTION(createTypeError("Unitialized \"constant\" variable."));
 	}
-	if (!m_value)
-		return;
 	if (m_type)
 	{
-		m_value->expectType(*m_type);
-		if (m_isStateVariable && !m_type->externalType() && getVisibility() >= Visibility::Public)
-			BOOST_THROW_EXCEPTION(createTypeError("Internal type is not allowed for state variables."));
-
-		if (!FunctionType(*this).externalType())
-			BOOST_THROW_EXCEPTION(createTypeError("Internal type is not allowed for public state variables."));
+		if (m_value)
+			m_value->expectType(*m_type);
 	}
 	else
 	{
-		// no type declared and no previous assignment, infer the type
+		if (!m_value)
+			// This feature might be extended in the future.
+			BOOST_THROW_EXCEPTION(createTypeError("Assignment necessary for type detection."));
 		m_value->checkTypeRequirements();
 		TypePointer type = m_value->getType();
 		if (type->getCategory() == Type::Category::IntegerConstant)
@@ -405,6 +401,8 @@ void VariableDeclaration::checkTypeRequirements()
 			BOOST_THROW_EXCEPTION(createTypeError("Variable cannot have void type."));
 		m_type = type;
 	}
+	if (m_isStateVariable && getVisibility() >= Visibility::Public && !FunctionType(*this).externalType())
+		BOOST_THROW_EXCEPTION(createTypeError("Internal type is not allowed for public state variables."));
 }
 
 bool VariableDeclaration::isExternalFunctionParameter() const
diff --git a/libsolidity/Parser.cpp b/libsolidity/Parser.cpp
index 5c7676df5..43571314a 100644
--- a/libsolidity/Parser.cpp
+++ b/libsolidity/Parser.cpp
@@ -472,17 +472,18 @@ ASTPointer<TypeName> Parser::parseTypeName(bool _allowVar)
 	else
 		BOOST_THROW_EXCEPTION(createParserError("Expected type name"));
 
-	// Parse "[...]" postfixes for arrays.
-	while (m_scanner->getCurrentToken() == Token::LBrack)
-	{
-		m_scanner->next();
-		ASTPointer<Expression> length;
-		if (m_scanner->getCurrentToken() != Token::RBrack)
-			length = parseExpression();
-		nodeFactory.markEndPosition();
-		expectToken(Token::RBrack);
-		type = nodeFactory.createNode<ArrayTypeName>(type, length);
-	}
+	if (type)
+		// Parse "[...]" postfixes for arrays.
+		while (m_scanner->getCurrentToken() == Token::LBrack)
+		{
+			m_scanner->next();
+			ASTPointer<Expression> length;
+			if (m_scanner->getCurrentToken() != Token::RBrack)
+				length = parseExpression();
+			nodeFactory.markEndPosition();
+			expectToken(Token::RBrack);
+			type = nodeFactory.createNode<ArrayTypeName>(type, length);
+		}
 	return type;
 }
 
diff --git a/test/SolidityNameAndTypeResolution.cpp b/test/SolidityNameAndTypeResolution.cpp
index 74a488883..ffa78ed9e 100644
--- a/test/SolidityNameAndTypeResolution.cpp
+++ b/test/SolidityNameAndTypeResolution.cpp
@@ -99,7 +99,7 @@ BOOST_AUTO_TEST_CASE(smoke_test)
 {
 	char const* text = "contract test {\n"
 					   "  uint256 stateVariable1;\n"
-					   "  function fun(uint256 arg1) { var x; uint256 y; }"
+					   "  function fun(uint256 arg1) { uint256 y; }"
 					   "}\n";
 	ETH_TEST_CHECK_NO_THROW(parseTextAndResolveNames(text), "Parsing and Name Resolving Failed");
 }
@@ -1623,6 +1623,16 @@ BOOST_AUTO_TEST_CASE(bytes0_array)
 	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
 }
 
+BOOST_AUTO_TEST_CASE(uninitialized_var)
+{
+	char const* sourceCode = R"(
+		contract C {
+			function f() returns (uint) { var x; return 2; }
+		}
+	)";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(sourceCode), TypeError);
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 }
diff --git a/test/SolidityParser.cpp b/test/SolidityParser.cpp
index b76f00656..7cd8efce1 100644
--- a/test/SolidityParser.cpp
+++ b/test/SolidityParser.cpp
@@ -841,6 +841,15 @@ BOOST_AUTO_TEST_CASE(constant_is_keyword)
 	BOOST_CHECK_THROW(parseText(text), ParserError);
 }
 
+BOOST_AUTO_TEST_CASE(var_array)
+{
+	char const* text = R"(
+		contract Foo {
+			function f() { var[] a; }
+	})";
+	BOOST_CHECK_THROW(parseText(text), ParserError);
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 }