Merge pull request #5358 from ethereum/yulObjects

[Yul] Yul objects parser

Changelog.md

@@ -11,6 +11,7 @@ Compiler Features:
  * SMTChecker: Support ``msg``, ``tx`` and ``block`` member variables.
  * SMTChecker: Support ``gasleft()`` and ``blockhash()`` functions.
  * SMTChecker: Support internal bound function calls.
+ * Yul: Support Yul objects in ``--assemble`` and ``--yul`` commandline options.
 
 
 Bugfixes:

libsolidity/interface/AssemblyStack.cpp

@@ -30,6 +30,7 @@
 #include <libyul/AsmCodeGen.h>
 #include <libyul/backends/evm/EVMCodeTransform.h>
 #include <libyul/backends/evm/EVMAssembly.h>
+#include <libyul/ObjectParser.h>
 
 #include <libevmasm/Assembly.h>
 
@@ -69,30 +70,22 @@ bool AssemblyStack::parseAndAnalyze(std::string const& _sourceName, std::string
 	m_errors.clear();
 	m_analysisSuccessful = false;
 	m_scanner = make_shared<Scanner>(CharStream(_source), _sourceName);
-	m_parserResult = yul::Parser(m_errorReporter, languageToAsmFlavour(m_language)).parse(m_scanner, false);
+	m_parserResult = yul::ObjectParser(m_errorReporter, languageToAsmFlavour(m_language)).parse(m_scanner, false);
 	if (!m_errorReporter.errors().empty())
 		return false;
 	solAssert(m_parserResult, "");
-
+	solAssert(m_parserResult->code, "");
-	return analyzeParsed();
-}
-
-bool AssemblyStack::analyze(yul::Block const& _block, Scanner const* _scanner)
-{
-	m_errors.clear();
-	m_analysisSuccessful = false;
-	if (_scanner)
-		m_scanner = make_shared<Scanner>(*_scanner);
-	m_parserResult = make_shared<yul::Block>(_block);
 
 	return analyzeParsed();
 }
 
 bool AssemblyStack::analyzeParsed()
 {
-	m_analysisInfo = make_shared<yul::AsmAnalysisInfo>();
+	solAssert(m_parserResult, "");
-	yul::AsmAnalyzer analyzer(*m_analysisInfo, m_errorReporter, m_evmVersion, boost::none, languageToAsmFlavour(m_language));
+	solAssert(m_parserResult->code, "");
-	m_analysisSuccessful = analyzer.analyze(*m_parserResult);
+	m_parserResult->analysisInfo = make_shared<yul::AsmAnalysisInfo>();
+	yul::AsmAnalyzer analyzer(*m_parserResult->analysisInfo, m_errorReporter, m_evmVersion, boost::none, languageToAsmFlavour(m_language));
+	m_analysisSuccessful = analyzer.analyze(*m_parserResult->code);
 	return m_analysisSuccessful;
 }
 
@@ -100,7 +93,8 @@ MachineAssemblyObject AssemblyStack::assemble(Machine _machine) const
 {
 	solAssert(m_analysisSuccessful, "");
 	solAssert(m_parserResult, "");
-	solAssert(m_analysisInfo, "");
+	solAssert(m_parserResult->code, "");
+	solAssert(m_parserResult->analysisInfo, "");
 
 	switch (_machine)
 	{
@@ -108,7 +102,7 @@ MachineAssemblyObject AssemblyStack::assemble(Machine _machine) const
 	{
 		MachineAssemblyObject object;
 		eth::Assembly assembly;
-		yul::CodeGenerator::assemble(*m_parserResult, *m_analysisInfo, assembly);
+		yul::CodeGenerator::assemble(*m_parserResult->code, *m_parserResult->analysisInfo, assembly);
 		object.bytecode = make_shared<eth::LinkerObject>(assembly.assemble());
 		object.assembly = assembly.assemblyString();
 		return object;
@@ -117,7 +111,7 @@ MachineAssemblyObject AssemblyStack::assemble(Machine _machine) const
 	{
 		MachineAssemblyObject object;
 		yul::EVMAssembly assembly(true);
-		yul::CodeTransform(assembly, *m_analysisInfo, m_language == Language::Yul, true)(*m_parserResult);
+		yul::CodeTransform(assembly, *m_parserResult->analysisInfo, m_language == Language::Yul, true)(*m_parserResult->code);
 		object.bytecode = make_shared<eth::LinkerObject>(assembly.finalize());
 		/// TODO: fill out text representation
 		return object;
@@ -132,5 +126,6 @@ MachineAssemblyObject AssemblyStack::assemble(Machine _machine) const
 string AssemblyStack::print() const
 {
 	solAssert(m_parserResult, "");
-	return yul::AsmPrinter(m_language == Language::Yul)(*m_parserResult);
+	solAssert(m_parserResult->code, "");
+	return m_parserResult->toString(m_language == Language::Yul) + "\n";
 }

libsolidity/interface/AssemblyStack.h

@@ -24,6 +24,9 @@
 #include <liblangutil/ErrorReporter.h>
 #include <liblangutil/EVMVersion.h>
 
+#include <libyul/Object.h>
+#include <libyul/ObjectParser.h>
+
 #include <libevmasm/LinkerObject.h>
 
 #include <string>
@@ -34,12 +37,6 @@ namespace langutil
 class Scanner;
 }
 
-namespace yul
-{
-struct AsmAnalysisInfo;
-struct Block;
-}
-
 namespace dev
 {
 namespace solidity
@@ -72,10 +69,6 @@ public:
 	/// Multiple calls overwrite the previous state.
 	bool parseAndAnalyze(std::string const& _sourceName, std::string const& _source);
 
-	/// Runs analysis step on the supplied block, returns false if input cannot be assembled.
-	/// Multiple calls overwrite the previous state.
-	bool analyze(yul::Block const& _block, langutil::Scanner const* _scanner = nullptr);
-
 	/// Run the assembly step (should only be called after parseAndAnalyze).
 	MachineAssemblyObject assemble(Machine _machine) const;
 
@@ -94,8 +87,7 @@ private:
 	std::shared_ptr<langutil::Scanner> m_scanner;
 
 	bool m_analysisSuccessful = false;
-	std::shared_ptr<yul::Block> m_parserResult;
+	std::shared_ptr<yul::Object> m_parserResult;
-	std::shared_ptr<yul::AsmAnalysisInfo> m_analysisInfo;
 	langutil::ErrorList m_errors;
 	langutil::ErrorReporter m_errorReporter;
 };

libyul/CMakeLists.txt

@@ -6,6 +6,8 @@ add_library(yul
 	AsmPrinter.cpp
 	AsmScope.cpp
 	AsmScopeFiller.cpp
+	Object.cpp
+	ObjectParser.cpp
 	backends/evm/EVMAssembly.cpp
 	backends/evm/EVMCodeTransform.cpp
 	optimiser/ASTCopier.cpp

libyul/Object.cpp

@@ -0,0 +1,61 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Yul code and data object container.
+ */
+
+#include <libyul/Object.h>
+
+#include <libyul/AsmPrinter.h>
+#include <libyul/Exceptions.h>
+
+#include <libdevcore/Visitor.h>
+#include <libdevcore/CommonData.h>
+
+#include <boost/algorithm/string/replace.hpp>
+
+using namespace dev;
+using namespace yul;
+using namespace std;
+
+namespace
+{
+
+string indent(std::string const& _input)
+{
+	if (_input.empty())
+		return _input;
+	return boost::replace_all_copy("    " + _input, "\n", "\n    ");
+}
+
+}
+
+string Data::toString(bool) const
+{
+	return "data \"" + name.str() + "\" hex\"" + dev::toHex(data) + "\"";
+}
+
+string Object::toString(bool _yul) const
+{
+	yulAssert(code, "No code");
+	string inner = "code " + AsmPrinter{_yul}(*code);
+
+	for (auto const& obj: subObjects)
+		inner += "\n" + obj->toString(_yul);
+
+	return "object \"" + name.str() + "\" {\n" + indent(inner) + "\n}";
+}

libyul/Object.h

@@ -0,0 +1,72 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Yul code and data object container.
+ */
+
+#pragma once
+
+#include <libyul/AsmDataForward.h>
+#include <libyul/YulString.h>
+
+#include <libdevcore/Common.h>
+
+#include <memory>
+
+namespace yul
+{
+struct AsmAnalysisInfo;
+
+
+/**
+ * Generic base class for both Yul objects and Yul data.
+ */
+struct ObjectNode
+{
+	virtual ~ObjectNode() {}
+	virtual std::string toString(bool _yul) const = 0;
+
+	YulString name;
+};
+
+/**
+ * Named data in Yul objects.
+ */
+struct Data: ObjectNode
+{
+	Data(YulString _name, dev::bytes _data): data(std::move(_data)) { name = _name; }
+	std::string toString(bool _yul) const override;
+
+	dev::bytes data;
+};
+
+/**
+ * Yul code and data object container.
+ */
+struct Object: ObjectNode
+{
+public:
+	/// @returns a (parseable) string representation. Includes types if @a _yul is set.
+	std::string toString(bool _yul) const override;
+
+	std::shared_ptr<Block> code;
+	std::vector<std::shared_ptr<ObjectNode>> subObjects;
+	std::map<YulString, size_t> subIndexByName;
+	std::shared_ptr<yul::AsmAnalysisInfo> analysisInfo;
+};
+
+}

libyul/ObjectParser.cpp

@@ -0,0 +1,146 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Parser for Yul code and data object container.
+ */
+
+#include <libyul/ObjectParser.h>
+
+#include <libyul/AsmParser.h>
+#include <libyul/Exceptions.h>
+
+#include <liblangutil/Token.h>
+
+using namespace dev;
+using namespace langutil;
+using namespace yul;
+using namespace std;
+
+
+shared_ptr<Object> ObjectParser::parse(shared_ptr<Scanner> const& _scanner, bool _reuseScanner)
+{
+	m_recursionDepth = 0;
+	try
+	{
+		shared_ptr<Object> object;
+		m_scanner = _scanner;
+		if (currentToken() == Token::LBrace)
+		{
+			// Special case: Code-only form.
+			object = make_shared<Object>();
+			object->name = YulString{"object"};
+			object->code = parseBlock();
+			if (!object->code)
+				return nullptr;
+		}
+		else
+			object = parseObject();
+		if (object && !_reuseScanner)
+			expectToken(Token::EOS);
+		return object;
+	}
+	catch (FatalError const&)
+	{
+		if (m_errorReporter.errors().empty())
+			throw; // Something is weird here, rather throw again.
+	}
+	return nullptr;
+}
+
+shared_ptr<Object> ObjectParser::parseObject(Object* _containingObject)
+{
+	RecursionGuard guard(*this);
+
+	if (currentToken() != Token::Identifier || currentLiteral() != "object")
+		fatalParserError("Expected keyword \"object\".");
+	advance();
+
+	shared_ptr<Object> ret = make_shared<Object>();
+	ret->name = parseUniqueName(_containingObject);
+
+	expectToken(Token::LBrace);
+
+	ret->code = parseCode();
+
+	while (currentToken() != Token::RBrace)
+	{
+		if (currentToken() == Token::Identifier && currentLiteral() == "object")
+			parseObject(ret.get());
+		else if (currentToken() == Token::Identifier && currentLiteral() == "data")
+			parseData(*ret);
+		else
+			fatalParserError("Expected keyword \"data\" or \"object\" or \"}\".");
+	}
+	if (_containingObject)
+		addNamedSubObject(*_containingObject, ret->name, ret);
+
+	expectToken(Token::RBrace);
+
+	return ret;
+}
+
+shared_ptr<Block> ObjectParser::parseCode()
+{
+	if (currentToken() != Token::Identifier || currentLiteral() != "code")
+		fatalParserError("Expected keyword \"code\".");
+	advance();
+
+	return parseBlock();
+}
+
+shared_ptr<Block> ObjectParser::parseBlock()
+{
+	Parser parser(m_errorReporter, m_flavour);
+	shared_ptr<Block> block = parser.parse(m_scanner, true);
+	yulAssert(block || m_errorReporter.hasErrors(), "Invalid block but no error!");
+	return block;
+}
+
+void ObjectParser::parseData(Object& _containingObject)
+{
+	solAssert(
+		currentToken() == Token::Identifier && currentLiteral() == "data",
+		"parseData called on wrong input."
+	);
+	advance();
+
+	YulString name = parseUniqueName(&_containingObject);
+
+	expectToken(Token::StringLiteral, false);
+	addNamedSubObject(_containingObject, name, make_shared<Data>(name, asBytes(currentLiteral())));
+	advance();
+}
+
+YulString ObjectParser::parseUniqueName(Object const* _containingObject)
+{
+	expectToken(Token::StringLiteral, false);
+	YulString name{currentLiteral()};
+	if (name.empty())
+		parserError("Object name cannot be empty.");
+	else if (_containingObject && _containingObject->name == name)
+		parserError("Object name cannot be the same as the name of the containing object.");
+	else if (_containingObject && _containingObject->subIndexByName.count(name))
+		parserError("Object name \"" + name.str() + "\" already exists inside the containing object.");
+	advance();
+	return name;
+}
+
+void ObjectParser::addNamedSubObject(Object& _container, YulString _name, shared_ptr<ObjectNode> _subObject)
+{
+	_container.subIndexByName[_name] = _container.subObjects.size();
+	_container.subObjects.emplace_back(std::move(_subObject));
+}

libyul/ObjectParser.h

@@ -0,0 +1,72 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Parser for Yul code and data object container.
+ */
+
+#pragma once
+
+#include <libyul/YulString.h>
+#include <libyul/Object.h>
+
+#include <liblangutil/ErrorReporter.h>
+#include <liblangutil/ParserBase.h>
+
+#include <libdevcore/Common.h>
+
+#include <memory>
+
+namespace langutil
+{
+class Scanner;
+}
+
+namespace yul
+{
+
+/**
+ * Yul object parser. Invokes the inline assembly parser.
+ */
+class ObjectParser: public langutil::ParserBase
+{
+public:
+	explicit ObjectParser(
+		langutil::ErrorReporter& _errorReporter,
+		yul::AsmFlavour _flavour = yul::AsmFlavour::Loose
+	):
+		ParserBase(_errorReporter), m_flavour(_flavour) {}
+
+	/// Parses a Yul object.
+	/// Falls back to code-only parsing if the source starts with `{`.
+	/// @param _reuseScanner if true, do check for end of input after the last `}`.
+	/// @returns an empty shared pointer on error.
+	std::shared_ptr<Object> parse(std::shared_ptr<langutil::Scanner> const& _scanner, bool _reuseScanner);
+
+private:
+	std::shared_ptr<Object> parseObject(Object* _containingObject = nullptr);
+	std::shared_ptr<Block> parseCode();
+	std::shared_ptr<Block> parseBlock();
+	void parseData(Object& _containingObject);
+
+	/// Tries to parse a name that is non-empty and unique inside the containing object.
+	YulString parseUniqueName(Object const* _containingObject);
+	void addNamedSubObject(Object& _container, YulString _name, std::shared_ptr<ObjectNode> _subObject);
+
+	yul::AsmFlavour m_flavour;
+};
+
+}

test/libsolidity/InlineAssembly.cpp

@@ -124,7 +124,8 @@ void parsePrintCompare(string const& _source, bool _canWarn = false)
 		BOOST_REQUIRE(Error::containsOnlyWarnings(stack.errors()));
 	else
 		BOOST_REQUIRE(stack.errors().empty());
-	BOOST_CHECK_EQUAL(stack.print(), _source);
+	string expectation = "object \"object\" {\n    code " + boost::replace_all_copy(_source, "\n", "\n    ") + "\n}\n";
+	BOOST_CHECK_EQUAL(stack.print(), expectation);
 }
 
 }
@@ -567,12 +568,14 @@ BOOST_AUTO_TEST_CASE(print_string_literals)
 BOOST_AUTO_TEST_CASE(print_string_literal_unicode)
 {
 	string source = "{ let x := \"\\u1bac\" }";
-	string parsed = "{\n    let x := \"\\xe1\\xae\\xac\"\n}";
+	string parsed = "object \"object\" {\n    code {\n        let x := \"\\xe1\\xae\\xac\"\n    }\n}\n";
 	AssemblyStack stack(dev::test::Options::get().evmVersion());
 	BOOST_REQUIRE(stack.parseAndAnalyze("", source));
 	BOOST_REQUIRE(stack.errors().empty());
 	BOOST_CHECK_EQUAL(stack.print(), parsed);
-	parsePrintCompare(parsed);
+
+	string parsedInner = "{\n    let x := \"\\xe1\\xae\\xac\"\n}";
+	parsePrintCompare(parsedInner);
 }
 
 BOOST_AUTO_TEST_CASE(print_if)

test/libyul/ObjectParser.cpp

@@ -0,0 +1,257 @@
+/*
+    This file is part of solidity.
+
+    solidity is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    solidity is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @date 2018
+ * Unit tests for the Yul object parser.
+ */
+
+#include <test/Options.h>
+
+#include <test/libsolidity/ErrorCheck.h>
+
+#include <libsolidity/interface/AssemblyStack.h>
+
+#include <boost/optional.hpp>
+#include <boost/algorithm/string/replace.hpp>
+
+#include <string>
+#include <memory>
+
+using namespace std;
+using namespace langutil;
+
+namespace dev
+{
+namespace yul
+{
+namespace test
+{
+
+namespace
+{
+
+std::pair<bool, ErrorList> parse(string const& _source)
+{
+	try
+	{
+		solidity::AssemblyStack asmStack(
+			dev::test::Options::get().evmVersion(),
+			solidity::AssemblyStack::Language::StrictAssembly
+		);
+		bool success = asmStack.parseAndAnalyze("source", _source);
+		return {success, asmStack.errors()};
+	}
+	catch (FatalError const&)
+	{
+		BOOST_FAIL("Fatal error leaked.");
+	}
+	return {false, {}};
+}
+
+boost::optional<Error> parseAndReturnFirstError(string const& _source, bool _allowWarnings = true)
+{
+	bool success;
+	ErrorList errors;
+	tie(success, errors) = parse(_source);
+	if (!success)
+	{
+		BOOST_REQUIRE_EQUAL(errors.size(), 1);
+		return *errors.front();
+	}
+	else
+	{
+		// If success is true, there might still be an error in the assembly stage.
+		if (_allowWarnings && Error::containsOnlyWarnings(errors))
+			return {};
+		else if (!errors.empty())
+		{
+			if (!_allowWarnings)
+				BOOST_CHECK_EQUAL(errors.size(), 1);
+			return *errors.front();
+		}
+	}
+	return {};
+}
+
+bool successParse(std::string const& _source, bool _allowWarnings = true)
+{
+	return !parseAndReturnFirstError(_source, _allowWarnings);
+}
+
+Error expectError(std::string const& _source, bool _allowWarnings = false)
+{
+
+	auto error = parseAndReturnFirstError(_source, _allowWarnings);
+	BOOST_REQUIRE(error);
+	return *error;
+}
+
+}
+
+#define CHECK_ERROR(text, typ, substring) \
+do \
+{ \
+	Error err = expectError((text), false); \
+	BOOST_CHECK(err.type() == (Error::Type::typ)); \
+	BOOST_CHECK(solidity::searchErrorMessage(err, (substring))); \
+} while(0)
+
+BOOST_AUTO_TEST_SUITE(YulObjectParser)
+
+BOOST_AUTO_TEST_CASE(empty_code)
+{
+	BOOST_CHECK(successParse("{ }"));
+}
+
+BOOST_AUTO_TEST_CASE(object_with_empty_code)
+{
+	BOOST_CHECK(successParse("object \"a\" { code { } }"));
+}
+
+BOOST_AUTO_TEST_CASE(non_object)
+{
+	CHECK_ERROR("code {}", ParserError, "Expected keyword \"object\"");
+}
+
+BOOST_AUTO_TEST_CASE(empty_name)
+{
+	CHECK_ERROR("object \"\" { code {} }", ParserError, "Object name cannot be empty");
+}
+
+BOOST_AUTO_TEST_CASE(recursion_depth)
+{
+	string input;
+	for (size_t i = 0; i < 20000; i++)
+		input += "object \"a" + to_string(i) + "\" { code {} ";
+	for (size_t i = 0; i < 20000; i++)
+		input += "}";
+
+	CHECK_ERROR(input, ParserError, "recursion");
+}
+
+BOOST_AUTO_TEST_CASE(object_with_code)
+{
+	BOOST_CHECK(successParse("object \"a\" { code { let x := mload(0) sstore(0, x) } }"));
+}
+
+BOOST_AUTO_TEST_CASE(object_with_code_and_data)
+{
+	BOOST_CHECK(successParse("object \"a\" { code { let x := mload(0) sstore(0, x) } data \"b\" hex\"01010202\" }"));
+}
+
+BOOST_AUTO_TEST_CASE(object_with_non_code_at_start)
+{
+	CHECK_ERROR("object \"a\" { data \"d\" hex\"0102\" code {  } }", ParserError, "Expected keyword \"code\"");
+}
+
+BOOST_AUTO_TEST_CASE(nested_object)
+{
+	string code = R"(
+		object "outer" {
+			code { let x := mload(0) }
+			data "x" "stringdata"
+			object "inner" {
+				code { mstore(0, 1) }
+				object "inner inner" { code {} }
+				data "innerx" "abc"
+				data "innery" "def"
+			}
+		}
+	)";
+	BOOST_CHECK(successParse(code));
+}
+
+BOOST_AUTO_TEST_CASE(incomplete)
+{
+	CHECK_ERROR("object \"abc\" { code {} } object", ParserError, "Expected end of source");
+}
+
+BOOST_AUTO_TEST_CASE(reuse_object_name)
+{
+	string code = R"(
+		object "outer" {
+			code { }
+			data "outer" "stringdata"
+		}
+	)";
+	CHECK_ERROR(code, ParserError, "Object name cannot be the same as the name of the containing object");
+}
+
+BOOST_AUTO_TEST_CASE(reuse_object_in_subobject)
+{
+	string code = R"(
+		object "outer" {
+			code { }
+			object "outer" { code {} }
+		}
+	)";
+	CHECK_ERROR(code, ParserError, "Object name cannot be the same as the name of the containing object");
+}
+
+BOOST_AUTO_TEST_CASE(reuse_object_of_sibling)
+{
+	string code = R"(
+		object "O" {
+			code { }
+			object "i" { code {} }
+			data "i" "abc"
+		}
+	)";
+	CHECK_ERROR(code, ParserError, "already exists inside the");
+}
+
+BOOST_AUTO_TEST_CASE(to_string)
+{
+	string code = R"(
+		object "O" {
+			code { let x := mload(0) if x { sstore(0, 1) } }
+			object "i" { code {} data "j" "def" }
+			data "j" "abc"
+			data "k" hex"010203"
+		}
+	)";
+	string expectation = R"(object "O" {
+	code {
+		let x := mload(0)
+		if x
+		{
+			sstore(0, 1)
+		}
+	}
+	object "i" {
+		code {
+		}
+		data "j" hex"646566"
+	}
+	data "j" hex"616263"
+	data "k" hex"010203"
+}
+)";
+	expectation = boost::replace_all_copy(expectation, "\t", "    ");
+	solidity::AssemblyStack asmStack(
+		dev::test::Options::get().evmVersion(),
+		solidity::AssemblyStack::Language::StrictAssembly
+	);
+	BOOST_REQUIRE(asmStack.parseAndAnalyze("source", code));
+	BOOST_CHECK_EQUAL(asmStack.print(), expectation);
+}
+
+BOOST_AUTO_TEST_SUITE_END()
+
+}
+}
+} // end namespaces