Adds support for string literals to soltest.

test/libsolidity/semanticTests/smoke_test.sol

@@ -20,6 +20,15 @@ contract C {
     function m(bytes memory b) public returns (bytes memory) {
         return b;
     }
+    function n() public returns (string memory) {
+        return "any";
+    }
+    function o() public returns (string memory, string memory) {
+        return ("any", "any");
+    }
+    function p() public returns (string memory, uint, string memory) {
+        return ("any", 42, "any");
+    }
 }
 // ----
 // _() -> FAILURE
@@ -33,3 +42,6 @@ contract C {
 // m(bytes): 32, 32, 0x20 -> 32, 32, 0x20
 // m(bytes): 32, 3, hex"AB33BB" -> 32, 3, left(0xAB33BB)
 // m(bytes): 32, 3, hex"AB33FF" -> 32, 3, hex"ab33ff0000000000000000000000000000000000000000000000000000000000"
+// n() -> 0x20, 3, "any"
+// o() -> 0x40, 0x80, 3, "any", 3, "any"
+// p() -> 0x60, 0x2a, 0xa0, 3, "any", 3, "any"

test/libsolidity/util/TestFileParser.cpp

@@ -290,11 +290,22 @@ tuple<bytes, ABIType, string> TestFileParser::parseABITypeLiteral()
 				throw Error(Error::Type::ParserError, "Invalid hex string literal.");
 			if (alignment != DeclaredAlignment::None)
 				throw Error(Error::Type::ParserError, "Hex string literals cannot be aligned or padded.");
-			string parsed = parseHexNumber();
+			string parsed = parseString();
 			rawString += "hex\"" + parsed + "\"";
-			result = convertHexString(parsed);
+			result = convertHexNumber(parsed);
 			abiType = ABIType{ABIType::HexString, ABIType::AlignNone, result.size()};
 		}
+		else if (accept(Token::String))
+		{
+			if (isSigned)
+				throw Error(Error::Type::ParserError, "Invalid string literal.");
+			if (alignment != DeclaredAlignment::None)
+				throw Error(Error::Type::ParserError, "String literals cannot be aligned or padded.");
+			abiType = ABIType{ABIType::String, ABIType::AlignLeft, 32};
+			string parsed = parseString();
+			rawString += "\"" + parsed + "\"";
+			result = applyAlign(DeclaredAlignment::Left, abiType, convertString(parsed));
+		}
 		else if (accept(Token::Number))
 		{
 			auto type = isSigned ? ABIType::SignedDec : ABIType::UnsignedDec;
@@ -395,6 +406,13 @@ string TestFileParser::parseHexNumber()
 	return literal;
 }
 
+string TestFileParser::parseString()
+{
+	string literal = m_scanner.currentLiteral();
+	expect(Token::String);
+	return literal;
+}
+
 bytes TestFileParser::convertBoolean(string const& _literal)
 {
 	if (_literal == "true")
@@ -422,13 +440,9 @@ bytes TestFileParser::convertHexNumber(string const& _literal)
 	try
 	{
 		if (_literal.size() % 2)
-		{
 			throw Error(Error::Type::ParserError, "Hex number encoding invalid.");
-		}
 		else
-		{
 			return fromHex(_literal);
-		}
 	}
 	catch (std::exception const&)
 	{
@@ -436,18 +450,15 @@ bytes TestFileParser::convertHexNumber(string const& _literal)
 	}
 }
 
-bytes TestFileParser::convertHexString(string const& _literal)
+bytes TestFileParser::convertString(string const& _literal)
 {
 	try
 	{
-		if (_literal.size() % 2)
-			throw Error(Error::Type::ParserError, "Hex string encoding invalid.");
-		else
-			return fromHex(_literal);
+		return asBytes(_literal);
 	}
 	catch (std::exception const&)
 	{
-		throw Error(Error::Type::ParserError, "Hex string encoding invalid.");
+		throw Error(Error::Type::ParserError, "String encoding invalid.");
 	}
 }
 
@@ -525,9 +536,7 @@ void TestFileParser::Scanner::scanNextToken()
 			token = selectToken(Token::RBrack);
 			break;
 		case '\"':
-			advance();
-			token = selectToken(Token::HexNumber, scanHexNumber());
-			advance();
+			token = selectToken(Token::String, scanString());
 			break;
 		default:
 			if (isIdentifierStart(current()))
@@ -610,3 +619,16 @@ string TestFileParser::Scanner::scanHexNumber()
 	}
 	return number;
 }
+
+string TestFileParser::Scanner::scanString()
+{
+	string str;
+	advance();
+
+	while (current() != '\"')
+	{
+		str += current();
+		advance();
+	}
+	return str;
+}

test/libsolidity/util/TestFileParser.h

@@ -57,6 +57,7 @@ namespace test
 	T(Comment, "#", 0)             \
 	T(Number, "number", 0)         \
 	T(HexNumber, "hex_number", 0)  \
+	T(String, "string", 0)         \
 	T(Identifier, "identifier", 0) \
 	/* type keywords */            \
 	K(Ether, "ether", 0)           \
@@ -111,7 +112,8 @@ struct ABIType
 		UnsignedDec,
 		SignedDec,
 		Hex,
-		HexString
+		HexString,
+		String
 	};
 	enum Align
 	{
@@ -300,6 +302,7 @@ private:
 		std::string scanIdentifierOrKeyword();
 		std::string scanDecimalNumber();
 		std::string scanHexNumber();
+		std::string scanString();
 
 	private:
 		using TokenDesc = std::pair<Token, std::string>;
@@ -375,6 +378,9 @@ private:
 	/// Parses the current hex number literal.
 	std::string parseHexNumber();
 
+	/// Parses the current string literal.
+	std::string parseString();
+
 	/// Tries to convert \param _literal to an unpadded `bytes`
 	/// representation of the boolean number literal. Throws if conversion fails.
 	bytes convertBoolean(std::string const& _literal);
@@ -387,9 +393,9 @@ private:
 	/// representation of the hex literal. Throws if conversion fails.
 	bytes convertHexNumber(std::string const& _literal);
 
-	/// Tries to convert \param _literal to left-aligned, unpadded `bytes`
-	/// representation of the hex string literal. Throws if conversion fails.
-	bytes convertHexString(std::string const& _literal);
+	/// Tries to convert \param _literal to an unpadded `bytes`
+	/// representation of the string literal. Throws if conversion fails.
+	bytes convertString(std::string const& _literal);
 
 	/// A scanner instance
 	Scanner m_scanner;

test/libsolidity/util/TestFileParserTests.cpp

@@ -344,6 +344,39 @@ BOOST_AUTO_TEST_CASE(call_arguments_hex_string_lowercase)
 	);
 }
 
+BOOST_AUTO_TEST_CASE(call_arguments_string)
+{
+	char const* source = R"(
+		// f(string): 0x20, 3, "any" ->
+	)";
+	auto const calls = parse(source);
+	BOOST_REQUIRE_EQUAL(calls.size(), 1);
+	testFunctionCall(
+		calls.at(0),
+		Mode::SingleLine,
+		"f(string)",
+		false,
+		fmt::encodeDyn(string{"any"})
+	);
+}
+
+BOOST_AUTO_TEST_CASE(call_return_string)
+{
+	char const* source = R"(
+		// f() -> 0x20, 3, "any"
+	)";
+	auto const calls = parse(source);
+	BOOST_REQUIRE_EQUAL(calls.size(), 1);
+	testFunctionCall(
+		calls.at(0),
+		Mode::SingleLine,
+		"f()",
+		false,
+		fmt::encodeArgs(),
+		fmt::encodeDyn(string{"any"})
+	);
+}
+
 BOOST_AUTO_TEST_CASE(call_arguments_tuple)
 {
 	char const* source = R"(

test/libsolidity/util/TestFunctionCall.cpp

@@ -35,6 +35,7 @@ static regex s_uintType{"(uint\\d*)"};
 static regex s_intType{"(int\\d*)"};
 static regex s_bytesType{"(bytes\\d+)"};
 static regex s_dynBytesType{"(\\bbytes\\b)"};
+static regex s_stringType{"(string)"};
 
 /// Translates Solidity's ABI types into the internal type representation of
 /// soltest.
@@ -55,6 +56,12 @@ auto contractABITypes(string const& _type) -> vector<ABIType>
 		abiTypes.push_back(ABIType{ABIType::UnsignedDec, ABIType::AlignRight, 32});
 		abiTypes.push_back(ABIType{ABIType::HexString, ABIType::AlignLeft, 32});
 	}
+	else if (regex_match(_type, s_stringType))
+	{
+		abiTypes.push_back(ABIType{ABIType::UnsignedDec, ABIType::AlignRight, 32});
+		abiTypes.push_back(ABIType{ABIType::UnsignedDec, ABIType::AlignRight, 32});
+		abiTypes.push_back(ABIType{ABIType::String, ABIType::AlignLeft, 32});
+	}
 	else
 		abiTypes.push_back(ABIType{ABIType::None, ABIType::AlignRight, 0});
 	return abiTypes;
@@ -319,6 +326,25 @@ string TestFunctionCall::formatBytesRange(
 	case ABIType::HexString:
 		os << "hex\"" << toHex(_bytes) << "\"";
 		break;
+	case ABIType::String:
+	{
+		os << "\"";
+		bool expectZeros = false;
+		for (auto const& v: _bytes)
+		{
+			if (expectZeros && v != 0)
+				return {};
+			if (v == 0) expectZeros = true;
+			else
+			{
+				if (!isprint(v) || v == '"')
+					return {};
+				os << v;
+			}
+		}
+		os << "\"";
+		break;
+	}
 	case ABIType::Failure:
 		break;
 	case ABIType::None: