Merge pull request #1544 from VoR0220/fixedPointTypeResolution

Fixed point type resolution

5 files changed, 164 insertions, 182 deletions

diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index 76bfb1a8..bcfccc3e 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -196,9 +196,9 @@ TypePointer Type::fromElementaryTypeName(ElementaryTypeNameToken const& _type)
 	case Token::UInt:
 		return make_shared<IntegerType>(256, IntegerType::Modifier::Unsigned);
 	case Token::Fixed:
-		return make_shared<FixedPointType>(128, 128, FixedPointType::Modifier::Signed);
+		return make_shared<FixedPointType>(128, 19, FixedPointType::Modifier::Signed);
 	case Token::UFixed:
-		return make_shared<FixedPointType>(128, 128, FixedPointType::Modifier::Unsigned);
+		return make_shared<FixedPointType>(128, 19, FixedPointType::Modifier::Unsigned);
 	case Token::Byte:
 		return make_shared<FixedBytesType>(1);
 	case Token::Address:
@@ -352,12 +352,11 @@ bool IntegerType::isImplicitlyConvertibleTo(Type const& _convertTo) const
 	else if (_convertTo.category() == Category::FixedPoint)
 	{
 		FixedPointType const& convertTo = dynamic_cast<FixedPointType const&>(_convertTo);
-		if (convertTo.integerBits() < m_bits || isAddress())
+
+		if (isAddress())
 			return false;
-		else if (isSigned())
-			return convertTo.isSigned();
 		else
-			return !convertTo.isSigned() || convertTo.integerBits() > m_bits;
+			return maxValue() <= convertTo.maxIntegerValue() && minValue() >= convertTo.minIntegerValue();
 	}
 	else
 		return false;
@@ -487,22 +486,20 @@ MemberList::MemberMap IntegerType::nativeMembers(ContractDefinition const*) cons
 		return MemberList::MemberMap();
 }
 
-FixedPointType::FixedPointType(int _integerBits, int _fractionalBits, FixedPointType::Modifier _modifier):
-	m_integerBits(_integerBits), m_fractionalBits(_fractionalBits), m_modifier(_modifier)
+FixedPointType::FixedPointType(int _totalBits, int _fractionalDigits, FixedPointType::Modifier _modifier):
+	m_totalBits(_totalBits), m_fractionalDigits(_fractionalDigits), m_modifier(_modifier)
 {
 	solAssert(
-		m_integerBits + m_fractionalBits > 0 && 
-		m_integerBits + m_fractionalBits <= 256 && 
-		m_integerBits % 8 == 0 && 
-		m_fractionalBits % 8 == 0,
+		8 <= m_totalBits && m_totalBits <= 256 && m_totalBits % 8 == 0 &&
+		0 <= m_fractionalDigits && m_fractionalDigits <= 80, 
 		"Invalid bit number(s) for fixed type: " + 
-		dev::toString(_integerBits) + "x" + dev::toString(_fractionalBits)
-				);
+		dev::toString(_totalBits) + "x" + dev::toString(_fractionalDigits)
+	);
 }
 
 string FixedPointType::identifier() const
 {
-	return "t_" + string(isSigned() ? "" : "u") + "fixed" + std::to_string(integerBits()) + "x" + std::to_string(fractionalBits());
+	return "t_" + string(isSigned() ? "" : "u") + "fixed" + std::to_string(m_totalBits) + "x" + std::to_string(m_fractionalDigits);
 }
 
 bool FixedPointType::isImplicitlyConvertibleTo(Type const& _convertTo) const
@@ -510,12 +507,10 @@ bool FixedPointType::isImplicitlyConvertibleTo(Type const& _convertTo) const
 	if (_convertTo.category() == category())
 	{
 		FixedPointType const& convertTo = dynamic_cast<FixedPointType const&>(_convertTo);
-		if (convertTo.m_integerBits < m_integerBits || convertTo.m_fractionalBits < m_fractionalBits)
+		if (convertTo.numBits() < m_totalBits || convertTo.fractionalDigits() < m_fractionalDigits)
 			return false;
-		else if (isSigned())
-			return convertTo.isSigned();
 		else
-			return !convertTo.isSigned() || (convertTo.m_integerBits > m_integerBits);
+			return convertTo.maxIntegerValue() >= maxIntegerValue() && convertTo.minIntegerValue() <= minIntegerValue();
 	}
 	return false;
 }
@@ -549,13 +544,30 @@ bool FixedPointType::operator==(Type const& _other) const
 	if (_other.category() != category())
 		return false;
 	FixedPointType const& other = dynamic_cast<FixedPointType const&>(_other);
-	return other.m_integerBits == m_integerBits && other.m_fractionalBits == m_fractionalBits && other.m_modifier == m_modifier;
+	return other.m_totalBits == m_totalBits && other.m_fractionalDigits == m_fractionalDigits && other.m_modifier == m_modifier;
 }
 
 string FixedPointType::toString(bool) const
 {
 	string prefix = isSigned() ? "fixed" : "ufixed";
-	return prefix + dev::toString(m_integerBits) + "x" + dev::toString(m_fractionalBits);
+	return prefix + dev::toString(m_totalBits) + "x" + dev::toString(m_fractionalDigits);
+}
+
+bigint FixedPointType::maxIntegerValue() const
+{
+	bigint maxValue = (bigint(1) << (m_totalBits - (isSigned() ? 1 : 0))) - 1;
+	return maxValue / pow(bigint(10), m_fractionalDigits);
+}
+
+bigint FixedPointType::minIntegerValue() const
+{
+	if (isSigned())
+	{
+		bigint minValue = -(bigint(1) << (m_totalBits - (isSigned() ? 1 : 0)));
+		return minValue / pow(bigint(10), m_fractionalDigits);
+	}
+	else
+		return bigint(0);
 }
 
 TypePointer FixedPointType::binaryOperatorResult(Token::Value _operator, TypePointer const& _other) const
@@ -743,13 +755,9 @@ bool RationalNumberType::isImplicitlyConvertibleTo(Type const& _convertTo) const
 	else if (_convertTo.category() == Category::FixedPoint)
 	{
 		if (auto fixed = fixedPointType())
-		{
-			// We disallow implicit conversion if we would have to truncate (fixedPointType()
-			// can return a type that requires truncation).
-			rational value = m_value * (bigint(1) << fixed->fractionalBits());
-			return value.denominator() == 1 && fixed->isImplicitlyConvertibleTo(_convertTo);
-		}
-		return false;
+			return fixed->isImplicitlyConvertibleTo(_convertTo);
+		else
+			return false;
 	}
 	else if (_convertTo.category() == Category::FixedBytes)
 	{
@@ -953,10 +961,9 @@ u256 RationalNumberType::literalValue(Literal const*) const
 	else
 	{
 		auto fixed = fixedPointType();
-		solAssert(!!fixed, "");
-		rational shifted = m_value * (bigint(1) << fixed->fractionalBits());
-		// truncate
-		shiftedValue = shifted.numerator() / shifted.denominator();
+		solAssert(fixed, "");
+		int fractionalDigits = fixed->fractionalDigits();
+		shiftedValue = (m_value.numerator() / m_value.denominator()) * pow(bigint(10), fractionalDigits);
 	}
 
 	// we ignore the literal and hope that the type was correctly determined
@@ -997,22 +1004,21 @@ shared_ptr<IntegerType const> RationalNumberType::integerType() const
 shared_ptr<FixedPointType const> RationalNumberType::fixedPointType() const
 {
 	bool negative = (m_value < 0);
-	unsigned fractionalBits = 0;
+	unsigned fractionalDigits = 0;
 	rational value = abs(m_value); // We care about the sign later.
 	rational maxValue = negative ? 
 		rational(bigint(1) << 255, 1):
 		rational((bigint(1) << 256) - 1, 1);
 
-	while (value * 0x100 <= maxValue && value.denominator() != 1 && fractionalBits < 256)
+	while (value * 10 <= maxValue && value.denominator() != 1 && fractionalDigits < 80)
 	{
-		value *= 0x100;
-		fractionalBits += 8;
+		value *= 10;
+		fractionalDigits++;
 	}
 	
 	if (value > maxValue)
 		return shared_ptr<FixedPointType const>();
-	// u256(v) is the actual value that will be put on the stack
-	// From here on, very similar to integerType()
+	// This means we round towards zero for positive and negative values.
 	bigint v = value.numerator() / value.denominator();
 	if (negative)
 		// modify value to satisfy bit requirements for negative numbers:
@@ -1022,26 +1028,11 @@ shared_ptr<FixedPointType const> RationalNumberType::fixedPointType() const
 	if (v > u256(-1))
 		return shared_ptr<FixedPointType const>();
 
-	unsigned totalBits = bytesRequired(v) * 8;
+	unsigned totalBits = max(bytesRequired(v), 1u) * 8;
 	solAssert(totalBits <= 256, "");
-	unsigned integerBits = totalBits >= fractionalBits ? totalBits - fractionalBits : 0;
-	// Special case: Numbers between -1 and 0 have their sign bit in the fractional part.
-	if (negative && abs(m_value) < 1 && totalBits > fractionalBits)
-	{
-		fractionalBits += 8;
-		integerBits = 0;
-	}
-
-	if (integerBits > 256 || fractionalBits > 256 || fractionalBits + integerBits > 256)
-		return shared_ptr<FixedPointType const>();
-	if (integerBits == 0 && fractionalBits == 0)
-	{
-		integerBits = 0;
-		fractionalBits = 8;
-	}
 
 	return make_shared<FixedPointType>(
-		integerBits, fractionalBits,
+		totalBits, fractionalDigits,
 		negative ? FixedPointType::Modifier::Signed : FixedPointType::Modifier::Unsigned
 	);
 }
diff --git a/libsolidity/ast/Types.h b/libsolidity/ast/Types.h
index c24cc11a..3d7dad16 100644
--- a/libsolidity/ast/Types.h
+++ b/libsolidity/ast/Types.h
@@ -342,7 +342,7 @@ public:
 	};
 	virtual Category category() const override { return Category::FixedPoint; }
 
-	explicit FixedPointType(int _integerBits, int _fractionalBits, Modifier _modifier = Modifier::Unsigned);
+	explicit FixedPointType(int _totalBits, int _fractionalDigits, Modifier _modifier = Modifier::Unsigned);
 
 	virtual std::string identifier() const override;
 	virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
@@ -352,8 +352,8 @@ public:
 
 	virtual bool operator==(Type const& _other) const override;
 
-	virtual unsigned calldataEncodedSize(bool _padded = true) const override { return _padded ? 32 : (m_integerBits + m_fractionalBits) / 8; }
-	virtual unsigned storageBytes() const override { return (m_integerBits + m_fractionalBits) / 8; }
+	virtual unsigned calldataEncodedSize(bool _padded = true) const override { return _padded ? 32 : m_totalBits / 8; }
+	virtual unsigned storageBytes() const override { return m_totalBits / 8; }
 	virtual bool isValueType() const override { return true; }
 
 	virtual std::string toString(bool _short) const override;
@@ -361,14 +361,21 @@ public:
 	virtual TypePointer encodingType() const override { return shared_from_this(); }
 	virtual TypePointer interfaceType(bool) const override { return shared_from_this(); }
 
-	int numBits() const { return m_integerBits + m_fractionalBits; }
-	int integerBits() const { return m_integerBits; }
-	int fractionalBits() const { return m_fractionalBits; }
+	/// Number of bits used for this type in total.
+	int numBits() const { return m_totalBits; }
+	/// Number of decimal digits after the radix point.
+	int fractionalDigits() const { return m_fractionalDigits; }
 	bool isSigned() const { return m_modifier == Modifier::Signed; }
+	/// @returns the largest integer value this type con hold. Note that this is not the
+	/// largest value in general.
+	bigint maxIntegerValue() const;
+	/// @returns the smallest integer value this type can hold. Note hat this is not the
+	/// smallest value in general.
+	bigint minIntegerValue() const;
 
 private:
-	int m_integerBits;
-	int m_fractionalBits;
+	int m_totalBits;
+	int m_fractionalDigits;
 	Modifier m_modifier;
 };
 
diff --git a/libsolidity/codegen/CompilerUtils.cpp b/libsolidity/codegen/CompilerUtils.cpp
index 7067ddd5..782aad9d 100644
--- a/libsolidity/codegen/CompilerUtils.cpp
+++ b/libsolidity/codegen/CompilerUtils.cpp
@@ -504,7 +504,7 @@ void CompilerUtils::convertType(
 			//shift all integer bits onto the left side of the fixed type
 			FixedPointType const& targetFixedPointType = dynamic_cast<FixedPointType const&>(_targetType);
 			if (auto typeOnStack = dynamic_cast<IntegerType const*>(&_typeOnStack))
-				if (targetFixedPointType.integerBits() > typeOnStack->numBits())
+				if (targetFixedPointType.numBits() > typeOnStack->numBits())
 					cleanHigherOrderBits(*typeOnStack);
 			solUnimplemented("Not yet implemented - FixedPointType.");
 		}
diff --git a/libsolidity/parsing/Token.cpp b/libsolidity/parsing/Token.cpp
index 66312f69..9cec0303 100644
--- a/libsolidity/parsing/Token.cpp
+++ b/libsolidity/parsing/Token.cpp
@@ -70,7 +70,7 @@ void ElementaryTypeNameToken::assertDetails(Token::Value _baseType, unsigned con
 	else if (_baseType == Token::UFixedMxN || _baseType == Token::FixedMxN)
 	{
 		solAssert(
-			_first + _second <= 256 && _first % 8 == 0 && _second % 8 == 0,
+			_first >= 8 && _first <= 256 && _first % 8 == 0 && _second <= 80,
 			"No elementary type " + string(Token::toString(_baseType)) + to_string(_first) + "x" + to_string(_second) + "."
 		);
 	}
@@ -157,12 +157,8 @@ tuple<Token::Value, unsigned int, unsigned int> Token::fromIdentifierOrKeyword(s
 			) {
 				int n = parseSize(positionX + 1, _literal.end());
 				if (
-					0 <= m && m <= 256 &&
-					8 <= n && n <= 256 &&
-					m + n > 0 &&
-					m + n <= 256 &&
-					m % 8 == 0 &&
-					n % 8 == 0
+					8 <= m && m <= 256 && m % 8 == 0 &&
+					0 <= n && n <= 80
 				) {
 					if (keyword == Token::UFixed)
 						return make_tuple(Token::UFixedMxN, m, n);
diff --git a/test/libsolidity/SolidityNameAndTypeResolution.cpp b/test/libsolidity/SolidityNameAndTypeResolution.cpp
index 2a5613c0..4b29243a 100644
--- a/test/libsolidity/SolidityNameAndTypeResolution.cpp
+++ b/test/libsolidity/SolidityNameAndTypeResolution.cpp
@@ -2290,6 +2290,9 @@ BOOST_AUTO_TEST_CASE(test_fromElementaryTypeName)
 	BOOST_CHECK(*Type::fromElementaryTypeName(ElementaryTypeNameToken(Token::BytesM, 30, 0)) == *make_shared<FixedBytesType>(30));
 	BOOST_CHECK(*Type::fromElementaryTypeName(ElementaryTypeNameToken(Token::BytesM, 31, 0)) == *make_shared<FixedBytesType>(31));
 	BOOST_CHECK(*Type::fromElementaryTypeName(ElementaryTypeNameToken(Token::BytesM, 32, 0)) == *make_shared<FixedBytesType>(32));
+
+	BOOST_CHECK(*Type::fromElementaryTypeName(ElementaryTypeNameToken(Token::Fixed, 0, 0)) == *make_shared<FixedPointType>(128, 19, FixedPointType::Modifier::Signed));
+	BOOST_CHECK(*Type::fromElementaryTypeName(ElementaryTypeNameToken(Token::UFixed, 0, 0)) == *make_shared<FixedPointType>(128, 19, FixedPointType::Modifier::Unsigned));
 }
 
 BOOST_AUTO_TEST_CASE(test_byte_is_alias_of_byte1)
@@ -4033,7 +4036,7 @@ BOOST_AUTO_TEST_CASE(invalid_fixed_types_0x7_mxn)
 			fixed0x7 a = .3;
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, DeclarationError, "Identifier not found");
 }
 
 BOOST_AUTO_TEST_CASE(invalid_fixed_types_long_invalid_identifier)
@@ -4043,7 +4046,7 @@ BOOST_AUTO_TEST_CASE(invalid_fixed_types_long_invalid_identifier)
 			fixed99999999999999999999999999999999999999x7 b = 9.5;
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, DeclarationError, "Identifier not found");
 }
 
 BOOST_AUTO_TEST_CASE(invalid_fixed_types_7x8_mxn)
@@ -4053,7 +4056,7 @@ BOOST_AUTO_TEST_CASE(invalid_fixed_types_7x8_mxn)
 			fixed7x8 c = 3.12345678;
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, DeclarationError, "Identifier not found");
 }
 
 BOOST_AUTO_TEST_CASE(library_instances_cannot_be_used)
@@ -4067,7 +4070,7 @@ BOOST_AUTO_TEST_CASE(library_instances_cannot_be_used)
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "Member \"l\" not found or not visible after argument-dependent lookup in library L");
 }
 
 BOOST_AUTO_TEST_CASE(invalid_fixed_type_long)
@@ -4079,7 +4082,7 @@ BOOST_AUTO_TEST_CASE(invalid_fixed_type_long)
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, DeclarationError, "Identifier not found");
 }
 
 BOOST_AUTO_TEST_CASE(fixed_type_int_conversion)
@@ -4087,8 +4090,8 @@ BOOST_AUTO_TEST_CASE(fixed_type_int_conversion)
 	char const* text = R"(
 		contract test {
 			function f() {
-				uint128 a = 3;
-				int128 b = 4;
+				uint64 a = 3;
+				int64 b = 4;
 				fixed c = b;
 				ufixed d = a;
 				c; d;
@@ -4137,7 +4140,7 @@ BOOST_AUTO_TEST_CASE(invalid_int_implicit_conversion_from_fixed)
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "Type fixed128x19 is not implicitly convertible to expected type int256");
 }
 
 BOOST_AUTO_TEST_CASE(rational_unary_operation)
@@ -4145,10 +4148,9 @@ BOOST_AUTO_TEST_CASE(rational_unary_operation)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed8x16 a = 3.25;
-				fixed8x16 b = -3.25;
-				a;
-				b;
+				ufixed16x2 a = 3.25;
+				fixed16x2 b = -3.25;
+				a; b;
 			}
 		}
 	)";
@@ -4156,13 +4158,13 @@ BOOST_AUTO_TEST_CASE(rational_unary_operation)
 	text = R"(
 		contract test {
 			function f() {
-				ufixed8x16 a = +3.25;
-				fixed8x16 b = -3.25;
+				ufixed16x2 a = +3.25;
+				fixed16x2 b = -3.25;
 				a; b;
 			}
 		}
 	)";
-	CHECK_WARNING(text,"Use of unary + is deprecated");
+	CHECK_WARNING(text, "Use of unary + is deprecated");
 	text = R"(
 		contract test {
 			function f(uint x) {
@@ -4179,10 +4181,10 @@ BOOST_AUTO_TEST_CASE(leading_zero_rationals_convert)
 	char const* text = R"(
 		contract A {
 			function f() {
-				ufixed0x8 a = 0.5;
-				ufixed0x56 b = 0.0000000000000006661338147750939242541790008544921875;
-				fixed0x8 c = -0.5;
-				fixed0x56 d = -0.0000000000000006661338147750939242541790008544921875;
+				ufixed16x2 a = 0.5;
+				ufixed256x52 b = 0.0000000000000006661338147750939242541790008544921875;
+				fixed16x2 c = -0.5;
+				fixed256x52 d = -0.0000000000000006661338147750939242541790008544921875;
 				a; b; c; d;
 			}
 		}
@@ -4195,12 +4197,12 @@ BOOST_AUTO_TEST_CASE(size_capabilities_of_fixed_point_types)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed248x8 a = 123456781234567979695948382928485849359686494864095409282048094275023098123.5;
-				ufixed0x256 b = 0.920890746623327805482905058466021565416131529487595827354393978494366605267637829135688384325135165352082715782143655824815685807141335814463015972119819459298455224338812271036061391763384038070334798471324635050876128428143374549108557403087615966796875;
-				ufixed0x256 c = 0.0000000000015198847363997979984922685411315294875958273543939784943666052676464653042434787697605517039455161817147718251801220885263595179331845639229818863564267318422845592626219390573301877339317935702714669975697814319204326238832436501979827880859375;
-				fixed248x8 d = -123456781234567979695948382928485849359686494864095409282048094275023098123.5;
-				fixed0x256 e = -0.93322335481643744342575580035176794825198893968114429702091846411734101080123092162893656820177312738451291806995868682861328125;
-				fixed0x256 g = -0.00011788606643744342575580035176794825198893968114429702091846411734101080123092162893656820177312738451291806995868682861328125;
+				ufixed256x1 a = 123456781234567979695948382928485849359686494864095409282048094275023098123.5;
+				ufixed256x77 b = 0.920890746623327805482905058466021565416131529487595827354393978494366605267637;
+				ufixed224x78 c = 0.000000000001519884736399797998492268541131529487595827354393978494366605267646;
+				fixed256x1 d = -123456781234567979695948382928485849359686494864095409282048094275023098123.5;
+				fixed256x76 e = -0.93322335481643744342575580035176794825198893968114429702091846411734101080123;
+				fixed256x79 g = -0.0001178860664374434257558003517679482519889396811442970209184641173410108012309;
 				a; b; c; d; e; g;
 			}
 		}
@@ -4208,17 +4210,30 @@ BOOST_AUTO_TEST_CASE(size_capabilities_of_fixed_point_types)
 	CHECK_SUCCESS(text);
 }
 
+BOOST_AUTO_TEST_CASE(zero_handling)
+{
+	char const* text = R"(
+		contract test {
+			function f() {
+				fixed16x2 a = 0; a;
+				ufixed32x1 b = 0; b;
+			}
+		}
+	)";
+	CHECK_SUCCESS(text);
+}
+
 BOOST_AUTO_TEST_CASE(fixed_type_invalid_implicit_conversion_size)
 {
 	char const* text = R"(
 		contract test {
 			function f() {
 				ufixed a = 11/4;
-				ufixed248x8 b = a;
+				ufixed248x8 b = a; b;
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "Type ufixed128x19 is not implicitly convertible to expected type ufixed248x8");
 }
 
 BOOST_AUTO_TEST_CASE(fixed_type_invalid_implicit_conversion_lost_data)
@@ -4226,11 +4241,11 @@ BOOST_AUTO_TEST_CASE(fixed_type_invalid_implicit_conversion_lost_data)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed0x256 a = 1/3;
+				ufixed256x1 a = 1/3; a;
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "is not implicitly convertible to expected type ufixed256x1");
 }
 
 BOOST_AUTO_TEST_CASE(fixed_type_valid_explicit_conversions)
@@ -4238,10 +4253,9 @@ BOOST_AUTO_TEST_CASE(fixed_type_valid_explicit_conversions)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed0x256 a = ufixed0x256(1/3);
-				ufixed0x248 b = ufixed0x248(1/3);
-				ufixed0x8 c = ufixed0x8(1/3);
-				a; b; c;
+				ufixed256x80 a = ufixed256x80(1/3); a;
+				ufixed248x80 b = ufixed248x80(1/3); b;
+				ufixed8x1 c = ufixed8x1(1/3); c;
 			}
 		}
 	)";
@@ -4253,23 +4267,35 @@ BOOST_AUTO_TEST_CASE(invalid_array_declaration_with_rational)
 	char const* text = R"(
 		contract test {
 			function f() {
-				uint[3.5] a;
+				uint[3.5] a; a;
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "Invalid array length, expected integer literal");
 }
 
-BOOST_AUTO_TEST_CASE(invalid_array_declaration_with_fixed_type)
+BOOST_AUTO_TEST_CASE(invalid_array_declaration_with_signed_fixed_type)
 {
 	char const* text = R"(
 		contract test {
 			function f() {
-				uint[fixed(3.5)] a;
+				uint[fixed(3.5)] a; a;
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "Invalid array length, expected integer literal");
+}
+
+BOOST_AUTO_TEST_CASE(invalid_array_declaration_with_unsigned_fixed_type)
+{
+	char const* text = R"(
+		contract test {
+			function f() {
+				uint[ufixed(3.5)] a; a;
+			}
+		}
+	)";
+	CHECK_ERROR(text, TypeError, "Invalid array length, expected integer literal");
 }
 
 BOOST_AUTO_TEST_CASE(rational_to_bytes_implicit_conversion)
@@ -4277,11 +4303,11 @@ BOOST_AUTO_TEST_CASE(rational_to_bytes_implicit_conversion)
 	char const* text = R"(
 		contract test {
 			function f() {
-				bytes32 c = 3.2;
+				bytes32 c = 3.2; c;
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "is not implicitly convertible to expected type bytes32");
 }
 
 BOOST_AUTO_TEST_CASE(fixed_to_bytes_implicit_conversion)
@@ -4290,18 +4316,18 @@ BOOST_AUTO_TEST_CASE(fixed_to_bytes_implicit_conversion)
 		contract test {
 			function f() {
 				fixed a = 3.25;
-				bytes32 c = a;
+				bytes32 c = a; c;
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "fixed128x19 is not implicitly convertible to expected type bytes32");
 }
 
 BOOST_AUTO_TEST_CASE(mapping_with_fixed_literal)
 {
 	char const* text = R"(
 		contract test {
-			mapping(ufixed8x248 => string) fixedString;
+			mapping(ufixed8x1 => string) fixedString;
 			function f() {
 				fixedString[0.5] = "Half";
 			}
@@ -4341,7 +4367,7 @@ BOOST_AUTO_TEST_CASE(inline_array_rationals)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed8x8[4] memory a = [3.5, 4.125, 2.5, 4.0];
+				ufixed128x3[4] memory a = [ufixed128x3(3.5), 4.125, 2.5, 4.0];
 			}
 		}
 	)";
@@ -4358,7 +4384,7 @@ BOOST_AUTO_TEST_CASE(rational_index_access)
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "rational_const 1/2 is not implicitly convertible to expected type uint256");
 }
 
 BOOST_AUTO_TEST_CASE(rational_to_fixed_literal_expression)
@@ -4366,12 +4392,12 @@ BOOST_AUTO_TEST_CASE(rational_to_fixed_literal_expression)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed8x8 a = 3.5 * 3;
-				ufixed8x8 b = 4 - 2.5;
-				ufixed8x8 c = 11 / 4;
-				ufixed16x240 d = 599 + 0.21875;
-				ufixed8x248 e = ufixed8x248(35.245 % 12.9);
-				ufixed8x248 f = ufixed8x248(1.2 % 2);
+				ufixed64x8 a = 3.5 * 3;
+				ufixed64x8 b = 4 - 2.5;
+				ufixed64x8 c = 11 / 4;
+				ufixed240x5 d = 599 + 0.21875;
+				ufixed256x80 e = ufixed256x80(35.245 % 12.9);
+				ufixed256x80 f = ufixed256x80(1.2 % 2);
 				fixed g = 2 ** -2;
 				a; b; c; d; e; f; g;
 			}
@@ -4380,7 +4406,7 @@ BOOST_AUTO_TEST_CASE(rational_to_fixed_literal_expression)
 	CHECK_SUCCESS(text);
 }
 
-BOOST_AUTO_TEST_CASE(rational_as_exponent_value_neg_decimal)
+BOOST_AUTO_TEST_CASE(rational_as_exponent_value_signed)
 {
 	char const* text = R"(
 		contract test {
@@ -4389,10 +4415,10 @@ BOOST_AUTO_TEST_CASE(rational_as_exponent_value_neg_decimal)
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
-BOOST_AUTO_TEST_CASE(rational_as_exponent_value_pos_decimal)
+BOOST_AUTO_TEST_CASE(rational_as_exponent_value_unsigned)
 {
 	char const* text = R"(
 		contract test {
@@ -4401,7 +4427,7 @@ BOOST_AUTO_TEST_CASE(rational_as_exponent_value_pos_decimal)
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
 BOOST_AUTO_TEST_CASE(rational_as_exponent_half)
@@ -4409,11 +4435,11 @@ BOOST_AUTO_TEST_CASE(rational_as_exponent_half)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed24x24 b = 2 ** (1/2);
+				2 ** (1/2);
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
 BOOST_AUTO_TEST_CASE(rational_as_exponent_value_neg_quarter)
@@ -4421,11 +4447,11 @@ BOOST_AUTO_TEST_CASE(rational_as_exponent_value_neg_quarter)
 	char const* text = R"(
 		contract test {
 			function f() {
-				fixed40x40 c = 42 ** (-1/4);
+				42 ** (-1/4);
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
 BOOST_AUTO_TEST_CASE(fixed_point_casting_exponents_15)
@@ -4433,23 +4459,11 @@ BOOST_AUTO_TEST_CASE(fixed_point_casting_exponents_15)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed a = 3 ** ufixed(1.5);
-			}
-		}
-	)";
-	BOOST_CHECK(!success(text));
-}
-
-BOOST_AUTO_TEST_CASE(fixed_point_casting_exponents_half)
-{
-	char const* text = R"(
-		contract test {
-			function f() {
-				ufixed b = 2 ** ufixed(1/2);
+				var a = 3 ** ufixed(1.5);
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
 BOOST_AUTO_TEST_CASE(fixed_point_casting_exponents_neg)
@@ -4457,23 +4471,11 @@ BOOST_AUTO_TEST_CASE(fixed_point_casting_exponents_neg)
 	char const* text = R"(
 		contract test {
 			function f() {
-				fixed c = 42 ** fixed(-1/4);
-			}
-		}
-	)";
-	BOOST_CHECK(!success(text));
-}
-
-BOOST_AUTO_TEST_CASE(fixed_point_casting_exponents_neg_decimal)
-{
-	char const* text = R"(
-		contract test {
-			function f() {
-				fixed d = 16 ** fixed(-0.5);
+				var c = 42 ** fixed(-1/4);
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
 BOOST_AUTO_TEST_CASE(var_capable_of_holding_constant_rationals)
@@ -4521,11 +4523,11 @@ BOOST_AUTO_TEST_CASE(rational_bitnot_unary_operation)
 	char const* text = R"(
 		contract test {
 			function f() {
-				fixed a = ~3.5;
+				~fixed(3.5);
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "cannot be applied");
 }
 
 BOOST_AUTO_TEST_CASE(rational_bitor_binary_operation)
@@ -4533,11 +4535,11 @@ BOOST_AUTO_TEST_CASE(rational_bitor_binary_operation)
 	char const* text = R"(
 		contract test {
 			function f() {
-				fixed a = 1.5 | 3;
+				fixed(1.5) | 3;
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
 BOOST_AUTO_TEST_CASE(rational_bitxor_binary_operation)
@@ -4545,11 +4547,11 @@ BOOST_AUTO_TEST_CASE(rational_bitxor_binary_operation)
 	char const* text = R"(
 		contract test {
 			function f() {
-				fixed a = 1.75 ^ 3;
+				fixed(1.75) ^ 3;
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
 BOOST_AUTO_TEST_CASE(rational_bitand_binary_operation)
@@ -4557,25 +4559,11 @@ BOOST_AUTO_TEST_CASE(rational_bitand_binary_operation)
 	char const* text = R"(
 		contract test {
 			function f() {
-				fixed a = 1.75 & 3;
-			}
-		}
-	)";
-	BOOST_CHECK(!success(text));
-}
-
-BOOST_AUTO_TEST_CASE(zero_handling)
-{
-	char const* text = R"(
-		contract test {
-			function f() {
-				fixed8x8 a = 0;
-				ufixed8x8 b = 0;
-				a; b;
+				fixed(1.75) & 3;
 			}
 		}
 	)";
-	CHECK_SUCCESS(text);
+	CHECK_ERROR(text, TypeError, "not compatible with types");
 }
 
 BOOST_AUTO_TEST_CASE(missing_bool_conversion)
@@ -4595,7 +4583,7 @@ BOOST_AUTO_TEST_CASE(integer_and_fixed_interaction)
 	char const* text = R"(
 		contract test {
 			function f() {
-				ufixed a = uint128(1) + ufixed(2);
+				ufixed a = uint64(1) + ufixed(2);
 			}
 		}
 	)";
@@ -4625,7 +4613,7 @@ BOOST_AUTO_TEST_CASE(one_divided_by_three_integer_conversion)
 			}
 		}
 	)";
-	BOOST_CHECK(!success(text));
+	CHECK_ERROR(text, TypeError, "is not implicitly convertible to expected type uint256. Try converting to type ufixed256x77");
 }
 
 BOOST_AUTO_TEST_CASE(unused_return_value)