Merge pull request #2312 from ethereum/parser-cleanup

Parser cleanup (remove dependency on Solidity AST)

5 files changed, 87 insertions, 94 deletions

diff --git a/libsolidity/inlineasm/AsmParser.cpp b/libsolidity/inlineasm/AsmParser.cpp
index 605d27be..80409c63 100644
--- a/libsolidity/inlineasm/AsmParser.cpp
+++ b/libsolidity/inlineasm/AsmParser.cpp
@@ -50,16 +50,16 @@ assembly::Block Parser::parseBlock()
 {
 	assembly::Block block = createWithLocation<Block>();
 	expectToken(Token::LBrace);
-	while (m_scanner->currentToken() != Token::RBrace)
+	while (currentToken() != Token::RBrace)
 		block.statements.emplace_back(parseStatement());
 	block.location.end = endPosition();
-	m_scanner->next();
+	advance();
 	return block;
 }
 
 assembly::Statement Parser::parseStatement()
 {
-	switch (m_scanner->currentToken())
+	switch (currentToken())
 	{
 	case Token::Let:
 		return parseVariableDeclaration();
@@ -92,10 +92,10 @@ assembly::Statement Parser::parseStatement()
 		if (m_julia)
 			break;
 		assembly::StackAssignment assignment = createWithLocation<assembly::StackAssignment>();
-		m_scanner->next();
+		advance();
 		expectToken(Token::Colon);
 		assignment.variableName.location = location();
-		assignment.variableName.name = m_scanner->currentLiteral();
+		assignment.variableName.name = currentLiteral();
 		if (!m_julia && instructions().count(assignment.variableName.name))
 			fatalParserError("Identifier expected, got instruction name.");
 		assignment.location.end = endPosition();
@@ -110,7 +110,7 @@ assembly::Statement Parser::parseStatement()
 	// literal,
 	// identifier (might turn into label or functional assignment)
 	Statement statement(parseElementaryOperation(false));
-	switch (m_scanner->currentToken())
+	switch (currentToken())
 	{
 	case Token::LParen:
 		return parseCall(std::move(statement));
@@ -119,15 +119,15 @@ assembly::Statement Parser::parseStatement()
 		if (statement.type() != typeid(assembly::Identifier))
 			fatalParserError("Label name / variable name must precede \":\".");
 		assembly::Identifier const& identifier = boost::get<assembly::Identifier>(statement);
-		m_scanner->next();
+		advance();
 		// identifier:=: should be parsed as identifier: =: (i.e. a label),
 		// while identifier:= (being followed by a non-colon) as identifier := (assignment).
-		if (m_scanner->currentToken() == Token::Assign && m_scanner->peekNextToken() != Token::Colon)
+		if (currentToken() == Token::Assign && peekNextToken() != Token::Colon)
 		{
 			assembly::Assignment assignment = createWithLocation<assembly::Assignment>(identifier.location);
 			if (!m_julia && instructions().count(identifier.name))
 				fatalParserError("Cannot use instruction names for identifier names.");
-			m_scanner->next();
+			advance();
 			assignment.variableName = identifier;
 			assignment.value.reset(new Statement(parseExpression()));
 			assignment.location.end = locationOf(*assignment.value).end;
@@ -174,7 +174,7 @@ assembly::Case Parser::parseCase()
 assembly::Statement Parser::parseExpression()
 {
 	Statement operation = parseElementaryOperation(true);
-	if (m_scanner->currentToken() == Token::LParen)
+	if (currentToken() == Token::LParen)
 		return parseCall(std::move(operation));
 	else
 		return operation;
@@ -207,7 +207,7 @@ std::map<string, dev::solidity::Instruction> const& Parser::instructions()
 assembly::Statement Parser::parseElementaryOperation(bool _onlySinglePusher)
 {
 	Statement ret;
-	switch (m_scanner->currentToken())
+	switch (currentToken())
 	{
 	case Token::Identifier:
 	case Token::Return:
@@ -215,14 +215,14 @@ assembly::Statement Parser::parseElementaryOperation(bool _onlySinglePusher)
 	case Token::Address:
 	{
 		string literal;
-		if (m_scanner->currentToken() == Token::Return)
+		if (currentToken() == Token::Return)
 			literal = "return";
-		else if (m_scanner->currentToken() == Token::Byte)
+		else if (currentToken() == Token::Byte)
 			literal = "byte";
-		else if (m_scanner->currentToken() == Token::Address)
+		else if (currentToken() == Token::Address)
 			literal = "address";
 		else
-			literal = m_scanner->currentLiteral();
+			literal = currentLiteral();
 		// first search the set of instructions.
 		if (!m_julia && instructions().count(literal))
 		{
@@ -237,7 +237,7 @@ assembly::Statement Parser::parseElementaryOperation(bool _onlySinglePusher)
 		}
 		else
 			ret = Identifier{location(), literal};
-		m_scanner->next();
+		advance();
 		break;
 	}
 	case Token::StringLiteral:
@@ -246,7 +246,7 @@ assembly::Statement Parser::parseElementaryOperation(bool _onlySinglePusher)
 	case Token::FalseLiteral:
 	{
 		LiteralKind kind = LiteralKind::Number;
-		switch (m_scanner->currentToken())
+		switch (currentToken())
 		{
 		case Token::StringLiteral:
 			kind = LiteralKind::String;
@@ -265,10 +265,10 @@ assembly::Statement Parser::parseElementaryOperation(bool _onlySinglePusher)
 		Literal literal{
 			location(),
 			kind,
-			m_scanner->currentLiteral(),
+			currentLiteral(),
 			""
 		};
-		m_scanner->next();
+		advance();
 		if (m_julia)
 		{
 			expectToken(Token::Colon);
@@ -297,7 +297,7 @@ assembly::VariableDeclaration Parser::parseVariableDeclaration()
 	while (true)
 	{
 		varDecl.variables.emplace_back(parseTypedName());
-		if (m_scanner->currentToken() == Token::Comma)
+		if (currentToken() == Token::Comma)
 			expectToken(Token::Comma);
 		else
 			break;
@@ -315,22 +315,22 @@ assembly::FunctionDefinition Parser::parseFunctionDefinition()
 	expectToken(Token::Function);
 	funDef.name = expectAsmIdentifier();
 	expectToken(Token::LParen);
-	while (m_scanner->currentToken() != Token::RParen)
+	while (currentToken() != Token::RParen)
 	{
 		funDef.arguments.emplace_back(parseTypedName());
-		if (m_scanner->currentToken() == Token::RParen)
+		if (currentToken() == Token::RParen)
 			break;
 		expectToken(Token::Comma);
 	}
 	expectToken(Token::RParen);
-	if (m_scanner->currentToken() == Token::Sub)
+	if (currentToken() == Token::Sub)
 	{
 		expectToken(Token::Sub);
 		expectToken(Token::GreaterThan);
 		while (true)
 		{
 			funDef.returns.emplace_back(parseTypedName());
-			if (m_scanner->currentToken() == Token::LBrace)
+			if (currentToken() == Token::LBrace)
 				break;
 			expectToken(Token::Comma);
 		}
@@ -359,7 +359,7 @@ assembly::Statement Parser::parseCall(assembly::Statement&& _instruction)
 		for (unsigned i = 0; i < args; ++i)
 		{
 			/// check for premature closing parentheses
-			if (m_scanner->currentToken() == Token::RParen)
+			if (currentToken() == Token::RParen)
 				fatalParserError(string(
 					"Expected expression (" +
 					instrInfo.name +
@@ -371,7 +371,7 @@ assembly::Statement Parser::parseCall(assembly::Statement&& _instruction)
 			ret.arguments.emplace_back(parseExpression());
 			if (i != args - 1)
 			{
-				if (m_scanner->currentToken() != Token::Comma)
+				if (currentToken() != Token::Comma)
 					fatalParserError(string(
 						"Expected comma (" +
 						instrInfo.name +
@@ -380,11 +380,11 @@ assembly::Statement Parser::parseCall(assembly::Statement&& _instruction)
 						" arguments)"
 					));
 				else
-					m_scanner->next();
+					advance();
 			}
 		}
 		ret.location.end = endPosition();
-		if (m_scanner->currentToken() == Token::Comma)
+		if (currentToken() == Token::Comma)
 			fatalParserError(
 				string("Expected ')' (" + instrInfo.name + " expects " + boost::lexical_cast<string>(args) + " arguments)")
 			);
@@ -397,10 +397,10 @@ assembly::Statement Parser::parseCall(assembly::Statement&& _instruction)
 		ret.functionName = std::move(boost::get<Identifier>(_instruction));
 		ret.location = ret.functionName.location;
 		expectToken(Token::LParen);
-		while (m_scanner->currentToken() != Token::RParen)
+		while (currentToken() != Token::RParen)
 		{
 			ret.arguments.emplace_back(parseExpression());
-			if (m_scanner->currentToken() == Token::RParen)
+			if (currentToken() == Token::RParen)
 				break;
 			expectToken(Token::Comma);
 		}
@@ -433,12 +433,12 @@ TypedName Parser::parseTypedName()
 
 string Parser::expectAsmIdentifier()
 {
-	string name = m_scanner->currentLiteral();
+	string name = currentLiteral();
 	if (m_julia)
 	{
-		if (m_scanner->currentToken() == Token::Bool)
+		if (currentToken() == Token::Bool)
 		{
-			m_scanner->next();
+			advance();
 			return name;
 		}
 	}
diff --git a/libsolidity/parsing/Parser.cpp b/libsolidity/parsing/Parser.cpp
index 72150a3e..5b318b2b 100644
--- a/libsolidity/parsing/Parser.cpp
+++ b/libsolidity/parsing/Parser.cpp
@@ -1437,5 +1437,49 @@ ASTPointer<ParameterList> Parser::createEmptyParameterList()
 	return nodeFactory.createNode<ParameterList>(vector<ASTPointer<VariableDeclaration>>());
 }
 
+string Parser::currentTokenName()
+{
+	Token::Value token = m_scanner->currentToken();
+	if (Token::isElementaryTypeName(token)) //for the sake of accuracy in reporting
+	{
+		ElementaryTypeNameToken elemTypeName = m_scanner->currentElementaryTypeNameToken();
+		return elemTypeName.toString();
+	}
+	else
+		return Token::name(token);
+}
+
+Token::Value Parser::expectAssignmentOperator()
+{
+	Token::Value op = m_scanner->currentToken();
+	if (!Token::isAssignmentOp(op))
+		fatalParserError(
+			string("Expected assignment operator,  got '") +
+			currentTokenName() +
+			string("'")
+		);
+	m_scanner->next();
+	return op;
+}
+
+ASTPointer<ASTString> Parser::expectIdentifierToken()
+{
+	Token::Value id = m_scanner->currentToken();
+	if (id != Token::Identifier)
+		fatalParserError(
+			string("Expected identifier, got '") +
+			currentTokenName() +
+			string("'")
+		);
+	return getLiteralAndAdvance();
+}
+
+ASTPointer<ASTString> Parser::getLiteralAndAdvance()
+{
+	ASTPointer<ASTString> identifier = make_shared<ASTString>(m_scanner->currentLiteral());
+	m_scanner->next();
+	return identifier;
+}
+
 }
 }
diff --git a/libsolidity/parsing/Parser.h b/libsolidity/parsing/Parser.h
index 282617ab..5ec3dbed 100644
--- a/libsolidity/parsing/Parser.h
+++ b/libsolidity/parsing/Parser.h
@@ -154,6 +154,11 @@ private:
 		std::vector<ASTPointer<PrimaryExpression>> const& _path,
 		std::vector<std::pair<ASTPointer<Expression>, SourceLocation>> const& _indices
 	);
+
+	std::string currentTokenName();
+	Token::Value expectAssignmentOperator();
+	ASTPointer<ASTString> expectIdentifierToken();
+	ASTPointer<ASTString> getLiteralAndAdvance();
 	///@}
 
 	/// Creates an empty ParameterList at the current location (used if parameters can be omitted).
diff --git a/libsolidity/parsing/ParserBase.cpp b/libsolidity/parsing/ParserBase.cpp
index 87d47f4b..ac103bda 100644
--- a/libsolidity/parsing/ParserBase.cpp
+++ b/libsolidity/parsing/ParserBase.cpp
@@ -80,62 +80,6 @@ void ParserBase::expectToken(Token::Value _value)
 	m_scanner->next();
 }
 
-Token::Value ParserBase::expectAssignmentOperator()
-{
-	Token::Value op = m_scanner->currentToken();
-	if (!Token::isAssignmentOp(op))
-	{
-		if (Token::isElementaryTypeName(op)) //for the sake of accuracy in reporting
-		{
-			ElementaryTypeNameToken elemTypeName = m_scanner->currentElementaryTypeNameToken();
-			fatalParserError(
-				string("Expected assignment operator,  got '") +
-				elemTypeName.toString() +
-				string("'")
-			);
-		}
-		else
-			fatalParserError(
-				string("Expected assignment operator,  got '") +
-				string(Token::name(m_scanner->currentToken())) +
-				string("'")
-			);
-	}
-	m_scanner->next();
-	return op;
-}
-
-ASTPointer<ASTString> ParserBase::expectIdentifierToken()
-{
-	Token::Value id = m_scanner->currentToken();
-	if (id != Token::Identifier)
-	{
-		if (Token::isElementaryTypeName(id)) //for the sake of accuracy in reporting
-		{
-			ElementaryTypeNameToken elemTypeName = m_scanner->currentElementaryTypeNameToken();
-			fatalParserError(
-				string("Expected identifier, got '") +
-				elemTypeName.toString() +
-				string("'")
-			);
-		}
-		else
-			fatalParserError(
-				string("Expected identifier, got '") +
-				string(Token::name(id)) +
-				string("'")
-			);
-	}
-	return getLiteralAndAdvance();
-}
-
-ASTPointer<ASTString> ParserBase::getLiteralAndAdvance()
-{
-	ASTPointer<ASTString> identifier = make_shared<ASTString>(m_scanner->currentLiteral());
-	m_scanner->next();
-	return identifier;
-}
-
 void ParserBase::parserError(string const& _description)
 {
 	auto err = make_shared<Error>(Error::Type::ParserError);
diff --git a/libsolidity/parsing/ParserBase.h b/libsolidity/parsing/ParserBase.h
index dfb7cab7..18b39a5e 100644
--- a/libsolidity/parsing/ParserBase.h
+++ b/libsolidity/parsing/ParserBase.h
@@ -24,8 +24,8 @@
 
 #include <memory>
 #include <libsolidity/interface/Exceptions.h>
+#include <libsolidity/parsing/Scanner.h>
 #include <libsolidity/parsing/Token.h>
-#include <libsolidity/ast/ASTForward.h>
 
 namespace dev
 {
@@ -47,14 +47,14 @@ protected:
 	/// End position of the current token
 	int endPosition() const;
 
-
 	///@{
 	///@name Helper functions
 	/// If current token value is not _value, throw exception otherwise advance token.
 	void expectToken(Token::Value _value);
-	Token::Value expectAssignmentOperator();
-	ASTPointer<ASTString> expectIdentifierToken();
-	ASTPointer<ASTString> getLiteralAndAdvance();
+	Token::Value currentToken() const { return m_scanner->currentToken(); }
+	Token::Value peekNextToken() const { return m_scanner->peekNextToken(); }
+	std::string currentLiteral() const { return m_scanner->currentLiteral(); }
+	Token::Value advance() { return m_scanner->next(); }
 	///@}
 
 	/// Creates a @ref ParserError and annotates it with the current position and the