path: root/solidityEndToEndTest.cpp

/*
    This file is part of cpp-ethereum.

    cpp-ethereum 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.

    cpp-ethereum 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 cpp-ethereum.  If not, see <http://www.gnu.org/licenses/>.
*/
/**
 * @author Christian <c@ethdev.com>
 * @date 2014
 * Unit tests for the solidity expression compiler, testing the behaviour of the code.
 */

#include <string>
#include <tuple>
#include <boost/test/unit_test.hpp>
#include <libethereum/State.h>
#include <libethereum/Executive.h>
#include <libsolidity/CompilerStack.h>

using namespace std;

namespace dev
{
/// Provider another overload for toBigEndian to encode arguments and return values.
inline bytes toBigEndian(bool _value) { return bytes({byte(_value)}); }

namespace solidity
{
namespace test
{

class ExecutionFramework
{
public:
    ExecutionFramework() { g_logVerbosity = 0; }

    bytes const& compileAndRun(string const& _sourceCode)
    {
        bytes code = dev::solidity::CompilerStack::staticCompile(_sourceCode);
        sendMessage(code, true);
        BOOST_REQUIRE(!m_output.empty());
        return m_output;
    }

    bytes const& callContractFunction(byte _index, bytes const& _data = bytes())
    {
        sendMessage(bytes(1, _index) + _data, false);
        return m_output;
    }

    template <class... Args>
    bytes const& callContractFunction(byte _index, Args const&... _arguments)
    {
        return callContractFunction(_index, argsToBigEndian(_arguments...));
    }

    template <class CppFunction, class... Args>
    void testSolidityAgainstCpp(byte _index, CppFunction const& _cppFunction, Args const&... _arguments)
    {
        bytes solidityResult = callContractFunction(_index, _arguments...);
        bytes cppResult = callCppAndEncodeResult(_cppFunction, _arguments...);
        BOOST_CHECK_MESSAGE(solidityResult == cppResult, "Computed values do not match."
                            "\nSolidity: " + toHex(solidityResult) + "\nC++:      " + toHex(cppResult));
    }

    template <class CppFunction, class... Args>
    void testSolidityAgainstCppOnRange(byte _index, CppFunction const& _cppFunction,
                                       u256 const& _rangeStart, u256 const& _rangeEnd)
    {
        for (u256 argument = _rangeStart; argument < _rangeEnd; ++argument)
        {
            bytes solidityResult = callContractFunction(_index, argument);
            bytes cppResult = callCppAndEncodeResult(_cppFunction, argument);
            BOOST_CHECK_MESSAGE(solidityResult == cppResult, "Computed values do not match."
                                "\nSolidity: " + toHex(solidityResult) + "\nC++:      " + toHex(cppResult) +
                                "\nArgument: " + toHex(toBigEndian(argument)));
        }
    }

private:
    template <class FirstArg, class... Args>
    bytes argsToBigEndian(FirstArg const& _firstArg, Args const&... _followingArgs) const
    {
        return toBigEndian(_firstArg) + argsToBigEndian(_followingArgs...);
    }

    bytes argsToBigEndian() const { return bytes(); }

    template <class CppFunction, class... Args>
    auto callCppAndEncodeResult(CppFunction const& _cppFunction, Args const&... _arguments)
    -> typename enable_if<is_void<decltype(_cppFunction(_arguments...))>::value, bytes>::type
    {
        _cppFunction(_arguments...);
        return bytes();
    }
    template <class CppFunction, class... Args>
    auto callCppAndEncodeResult(CppFunction const& _cppFunction, Args const&... _arguments)
    -> typename enable_if<!is_void<decltype(_cppFunction(_arguments...))>::value, bytes>::type
    {
        return toBigEndian(_cppFunction(_arguments...));
    }

    void sendMessage(bytes const& _data, bool _isCreation)
    {
        eth::Executive executive(m_state);
        eth::Transaction t = _isCreation ? eth::Transaction(0, m_gasPrice, m_gas, _data, 0, KeyPair::create().sec())
                                         : eth::Transaction(0, m_gasPrice, m_gas, m_contractAddress, _data, 0, KeyPair::create().sec());
        bytes transactionRLP = t.rlp();
        try
        {
            // this will throw since the transaction is invalid, but it should nevertheless store the transaction
            executive.setup(&transactionRLP);
        }
        catch (...) {}
        if (_isCreation)
        {
            BOOST_REQUIRE(!executive.create(Address(), 0, m_gasPrice, m_gas, &_data, Address()));
            m_contractAddress = executive.newAddress();
            BOOST_REQUIRE(m_contractAddress);
            BOOST_REQUIRE(m_state.addressHasCode(m_contractAddress));
        }
        else
        {
            BOOST_REQUIRE(m_state.addressHasCode(m_contractAddress));
            BOOST_REQUIRE(!executive.call(m_contractAddress, Address(), 0, m_gasPrice, &_data, m_gas, Address()));
        }
        BOOST_REQUIRE(executive.go());
        executive.finalize();
        m_output = executive.out().toVector();
    }

protected:
    Address m_contractAddress;
    eth::State m_state;
    u256 const m_gasPrice = 100 * eth::szabo;
    u256 const m_gas = 1000000;
    bytes m_output;
};

BOOST_FIXTURE_TEST_SUITE(SolidityCompilerEndToEndTest, ExecutionFramework)

BOOST_AUTO_TEST_CASE(smoke_test)
{
    char const* sourceCode = "contract test {\n"
                             "  function f(uint a) returns(uint d) { return a * 7; }\n"
                             "}\n";
    compileAndRun(sourceCode);
    testSolidityAgainstCppOnRange(0, [](u256 const& a) -> u256 { return a * 7; }, 0, 100);
}

BOOST_AUTO_TEST_CASE(empty_contract)
{
    char const* sourceCode = "contract test {\n"
                             "}\n";
    compileAndRun(sourceCode);
    BOOST_CHECK(callContractFunction(0, bytes()).empty());
}

BOOST_AUTO_TEST_CASE(recursive_calls)
{
    char const* sourceCode = "contract test {\n"
                             "  function f(uint n) returns(uint nfac) {\n"
                             "    if (n <= 1) return 1;\n"
                             "    else return n * f(n - 1);\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    function<u256(u256)> recursive_calls_cpp = [&recursive_calls_cpp](u256 const& n) -> u256
    {
        if (n <= 1)
            return 1;
        else
            return n * recursive_calls_cpp(n - 1);
    };

    testSolidityAgainstCppOnRange(0, recursive_calls_cpp, 0, 5);
}

BOOST_AUTO_TEST_CASE(multiple_functions)
{
    char const* sourceCode = "contract test {\n"
                             "  function a() returns(uint n) { return 0; }\n"
                             "  function b() returns(uint n) { return 1; }\n"
                             "  function c() returns(uint n) { return 2; }\n"
                             "  function f() returns(uint n) { return 3; }\n"
                             "}\n";
    compileAndRun(sourceCode);
    BOOST_CHECK(callContractFunction(0, bytes()) == toBigEndian(u256(0)));
    BOOST_CHECK(callContractFunction(1, bytes()) == toBigEndian(u256(1)));
    BOOST_CHECK(callContractFunction(2, bytes()) == toBigEndian(u256(2)));
    BOOST_CHECK(callContractFunction(3, bytes()) == toBigEndian(u256(3)));
    BOOST_CHECK(callContractFunction(4, bytes()) == bytes());
}

BOOST_AUTO_TEST_CASE(while_loop)
{
    char const* sourceCode = "contract test {\n"
                             "  function f(uint n) returns(uint nfac) {\n"
                             "    nfac = 1;\n"
                             "    var i = 2;\n"
                             "    while (i <= n) nfac *= i++;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);

    auto while_loop_cpp = [](u256 const& n) -> u256
    {
        u256 nfac = 1;
        u256 i = 2;
        while (i <= n)
            nfac *= i++;

        return nfac;
    };

    testSolidityAgainstCppOnRange(0, while_loop_cpp, 0, 5);
}

BOOST_AUTO_TEST_CASE(break_outside_loop)
{
    // break and continue outside loops should be simply ignored
    char const* sourceCode = "contract test {\n"
                             "  function f(uint x) returns(uint y) {\n"
                             "    break; continue; return 2;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    testSolidityAgainstCpp(0, [](u256 const&) -> u256 { return 2; }, u256(0));
}

BOOST_AUTO_TEST_CASE(nested_loops)
{
    // tests that break and continue statements in nested loops jump to the correct place
    char const* sourceCode = "contract test {\n"
                             "  function f(uint x) returns(uint y) {\n"
                             "    while (x > 1) {\n"
                             "      if (x == 10) break;\n"
                             "      while (x > 5) {\n"
                             "        if (x == 8) break;\n"
                             "        x--;\n"
                             "        if (x == 6) continue;\n"
                             "        return x;\n"
                             "      }\n"
                             "      x--;\n"
                             "      if (x == 3) continue;\n"
                             "      break;\n"
                             "    }\n"
                             "    return x;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);

    auto nested_loops_cpp = [](u256  n) -> u256
    {
        while (n > 1)
        {
            if (n == 10)
                break;
            while (n > 5)
            {
                if (n == 8)
                    break;
                n--;
                if (n == 6)
                    continue;
                return n;
            }
            n--;
            if (n == 3)
                continue;
            break;
        }

        return n;
    };

    testSolidityAgainstCppOnRange(0, nested_loops_cpp, 0, 12);
}

BOOST_AUTO_TEST_CASE(calling_other_functions)
{
    // note that the index of a function is its index in the sorted sequence of functions
    char const* sourceCode = "contract collatz {\n"
                             "  function run(uint x) returns(uint y) {\n"
                             "    while ((y = x) > 1) {\n"
                             "      if (x % 2 == 0) x = evenStep(x);\n"
                             "      else x = oddStep(x);\n"
                             "    }\n"
                             "  }\n"
                             "  function evenStep(uint x) returns(uint y) {\n"
                             "    return x / 2;\n"
                             "  }\n"
                             "  function oddStep(uint x) returns(uint y) {\n"
                             "    return 3 * x + 1;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);

    auto evenStep_cpp = [](u256 const& n) -> u256
    {
        return n / 2;
    };

    auto oddStep_cpp = [](u256 const& n) -> u256
    {
        return 3 * n + 1;
    };

    auto collatz_cpp = [&evenStep_cpp, &oddStep_cpp](u256 n) -> u256
    {
        u256 y;
        while ((y = n) > 1)
        {
            if (n % 2 == 0)
                n = evenStep_cpp(n);
            else
                n = oddStep_cpp(n);
        }
        return y;
    };

    testSolidityAgainstCpp(2, collatz_cpp, u256(0));
    testSolidityAgainstCpp(2, collatz_cpp, u256(1));
    testSolidityAgainstCpp(2, collatz_cpp, u256(2));
    testSolidityAgainstCpp(2, collatz_cpp, u256(8));
    testSolidityAgainstCpp(2, collatz_cpp, u256(127));
}

BOOST_AUTO_TEST_CASE(many_local_variables)
{
    char const* sourceCode = "contract test {\n"
                             "  function run(uint x1, uint x2, uint x3) returns(uint y) {\n"
                             "    var a = 0x1; var b = 0x10; var c = 0x100;\n"
                             "    y = a + b + c + x1 + x2 + x3;\n"
                             "    y += b + x2;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    auto f = [](u256 const& x1, u256 const& x2, u256 const& x3) -> u256
    {
        u256 a = 0x1;
        u256 b = 0x10;
        u256 c = 0x100;
        u256 y = a + b + c + x1 + x2 + x3;
        return y + b + x2;
    };
    testSolidityAgainstCpp(0, f, u256(0x1000), u256(0x10000), u256(0x100000));
}

BOOST_AUTO_TEST_CASE(packing_unpacking_types)
{
    char const* sourceCode = "contract test {\n"
                             "  function run(bool a, uint32 b, uint64 c) returns(uint256 y) {\n"
                             "    if (a) y = 1;\n"
                             "    y = y * 0x100000000 | ~b;\n"
                             "    y = y * 0x10000000000000000 | ~c;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    BOOST_CHECK(callContractFunction(0, fromHex("01""0f0f0f0f""f0f0f0f0f0f0f0f0"))
                == fromHex("00000000000000000000000000000000000000""01""f0f0f0f0""0f0f0f0f0f0f0f0f"));
}

BOOST_AUTO_TEST_CASE(multiple_return_values)
{
    char const* sourceCode = "contract test {\n"
                             "  function run(bool x1, uint x2) returns(uint y1, bool y2, uint y3) {\n"
                             "    y1 = x2; y2 = x1;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    BOOST_CHECK(callContractFunction(0, bytes(1, 1) + toBigEndian(u256(0xcd)))
                == toBigEndian(u256(0xcd)) + bytes(1, 1) + toBigEndian(u256(0)));
}

BOOST_AUTO_TEST_CASE(short_circuiting)
{
    char const* sourceCode = "contract test {\n"
                             "  function run(uint x) returns(uint y) {\n"
                             "    x == 0 || ((x = 8) > 0);\n"
                             "    return x;"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);

    auto short_circuiting_cpp = [](u256 n) -> u256
    {
        n == 0 || (n = 8) > 0;
        return n;
    };

    testSolidityAgainstCppOnRange(0, short_circuiting_cpp, 0, 2);
}

BOOST_AUTO_TEST_CASE(high_bits_cleaning)
{
    char const* sourceCode = "contract test {\n"
                             "  function run() returns(uint256 y) {\n"
                             "    uint32 x = uint32(0xffffffff) + 10;\n"
                             "    if (x >= 0xffffffff) return 0;\n"
                             "    return x;"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    auto high_bits_cleaning_cpp = []() -> u256
    {
        uint32_t x = uint32_t(0xffffffff) + 10;
        if (x >= 0xffffffff)
            return 0;
        return x;
    };
    testSolidityAgainstCpp(0, high_bits_cleaning_cpp);
}

BOOST_AUTO_TEST_CASE(sign_extension)
{
    char const* sourceCode = "contract test {\n"
                             "  function run() returns(uint256 y) {\n"
                             "    int64 x = -int32(0xff);\n"
                             "    if (x >= 0xff) return 0;\n"
                             "    return -uint256(x);"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    auto sign_extension_cpp = []() -> u256
    {
        int64_t x = -int32_t(0xff);
        if (x >= 0xff)
            return 0;
        return u256(x) * -1;
    };
    testSolidityAgainstCpp(0, sign_extension_cpp);
}

BOOST_AUTO_TEST_CASE(small_unsigned_types)
{
    char const* sourceCode = "contract test {\n"
                             "  function run() returns(uint256 y) {\n"
                             "    uint32 x = uint32(0xffffff) * 0xffffff;\n"
                             "    return x / 0x100;"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    auto small_unsigned_types_cpp = []() -> u256
    {
        uint32_t x = uint32_t(0xffffff) * 0xffffff;
        return x / 0x100;
    };
    testSolidityAgainstCpp(0, small_unsigned_types_cpp);
}

BOOST_AUTO_TEST_CASE(small_signed_types)
{
    char const* sourceCode = "contract test {\n"
                             "  function run() returns(int256 y) {\n"
                             "    return -int32(10) * -int64(20);\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    auto small_signed_types_cpp = []() -> u256
    {
        return -int32_t(10) * -int64_t(20);
    };
    testSolidityAgainstCpp(0, small_signed_types_cpp);
}

BOOST_AUTO_TEST_CASE(state_smoke_test)
{
    char const* sourceCode = "contract test {\n"
                             "  uint256 value1;\n"
                             "  uint256 value2;\n"
                             "  function get(uint8 which) returns (uint256 value) {\n"
                             "    if (which == 0) return value1;\n"
                             "    else return value2;\n"
                             "  }\n"
                             "  function set(uint8 which, uint256 value) {\n"
                             "    if (which == 0) value1 = value;\n"
                             "    else value2 = value;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    BOOST_CHECK(callContractFunction(0, bytes(1, 0x00)) == toBigEndian(u256(0)));
    BOOST_CHECK(callContractFunction(0, bytes(1, 0x01)) == toBigEndian(u256(0)));
    BOOST_CHECK(callContractFunction(1, bytes(1, 0x00) + toBigEndian(u256(0x1234))) == bytes());
    BOOST_CHECK(callContractFunction(1, bytes(1, 0x01) + toBigEndian(u256(0x8765))) == bytes());
    BOOST_CHECK(callContractFunction(0, bytes(1, 0x00)) == toBigEndian(u256(0x1234)));
    BOOST_CHECK(callContractFunction(0, bytes(1, 0x01)) == toBigEndian(u256(0x8765)));
    BOOST_CHECK(callContractFunction(1, bytes(1, 0x00) + toBigEndian(u256(0x3))) == bytes());
    BOOST_CHECK(callContractFunction(0, bytes(1, 0x00)) == toBigEndian(u256(0x3)));
}

BOOST_AUTO_TEST_CASE(simple_mapping)
{
    char const* sourceCode = "contract test {\n"
                             "  mapping(uint8 => uint8) table;\n"
                             "  function get(uint8 k) returns (uint8 v) {\n"
                             "    return table[k];\n"
                             "  }\n"
                             "  function set(uint8 k, uint8 v) {\n"
                             "    table[k] = v;\n"
                             "  }\n"
                             "}";
    compileAndRun(sourceCode);

    BOOST_CHECK(callContractFunction(0, bytes({0x00})) == bytes({0x00}));
    BOOST_CHECK(callContractFunction(0, bytes({0x01})) == bytes({0x00}));
    BOOST_CHECK(callContractFunction(0, bytes({0xa7})) == bytes({0x00}));
    callContractFunction(1, bytes({0x01, 0xa1}));
    BOOST_CHECK(callContractFunction(0, bytes({0x00})) == bytes({0x00}));
    BOOST_CHECK(callContractFunction(0, bytes({0x01})) == bytes({0xa1}));
    BOOST_CHECK(callContractFunction(0, bytes({0xa7})) == bytes({0x00}));
    callContractFunction(1, bytes({0x00, 0xef}));
    BOOST_CHECK(callContractFunction(0, bytes({0x00})) == bytes({0xef}));
    BOOST_CHECK(callContractFunction(0, bytes({0x01})) == bytes({0xa1}));
    BOOST_CHECK(callContractFunction(0, bytes({0xa7})) == bytes({0x00}));
    callContractFunction(1, bytes({0x01, 0x05}));
    BOOST_CHECK(callContractFunction(0, bytes({0x00})) == bytes({0xef}));
    BOOST_CHECK(callContractFunction(0, bytes({0x01})) == bytes({0x05}));
    BOOST_CHECK(callContractFunction(0, bytes({0xa7})) == bytes({0x00}));
}

BOOST_AUTO_TEST_CASE(mapping_state)
{
    char const* sourceCode = "contract Ballot {\n"
                             "  mapping(address => bool) canVote;\n"
                             "  mapping(address => uint) voteCount;\n"
                             "  mapping(address => bool) voted;\n"
                             "  function getVoteCount(address addr) returns (uint retVoteCount) {\n"
                             "    return voteCount[addr];\n"
                             "  }\n"
                             "  function grantVoteRight(address addr) {\n"
                             "    canVote[addr] = true;\n"
                             "  }\n"
                             "  function vote(address voter, address vote) returns (bool success) {\n"
                             "    if (!canVote[voter] || voted[voter]) return false;\n"
                             "    voted[voter] = true;\n"
                             "    voteCount[vote] = voteCount[vote] + 1;\n"
                             "    return true;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    class Ballot
    {
    public:
        u256 getVoteCount(u160 _address) { return m_voteCount[_address]; }
        void grantVoteRight(u160 _address) { m_canVote[_address] = true; }
        bool vote(u160 _voter, u160 _vote)
        {
            if (!m_canVote[_voter] || m_voted[_voter]) return false;
            m_voted[_voter] = true;
            m_voteCount[_vote]++;
            return true;
        }
    private:
        map<u160, bool> m_canVote;
        map<u160, u256> m_voteCount;
        map<u160, bool> m_voted;
    } ballot;

    auto getVoteCount = bind(&Ballot::getVoteCount, &ballot, _1);
    auto grantVoteRight = bind(&Ballot::grantVoteRight, &ballot, _1);
    auto vote = bind(&Ballot::vote, &ballot, _1, _2);
    testSolidityAgainstCpp(0, getVoteCount, u160(0));
    testSolidityAgainstCpp(0, getVoteCount, u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(2));
    // voting without vote right shourd be rejected
    testSolidityAgainstCpp(2, vote, u160(0), u160(2));
    testSolidityAgainstCpp(0, getVoteCount, u160(0));
    testSolidityAgainstCpp(0, getVoteCount, u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(2));
    // grant vote rights
    testSolidityAgainstCpp(1, grantVoteRight, u160(0));
    testSolidityAgainstCpp(1, grantVoteRight, u160(1));
    // vote, should increase 2's vote count
    testSolidityAgainstCpp(2, vote, u160(0), u160(2));
    testSolidityAgainstCpp(0, getVoteCount, u160(0));
    testSolidityAgainstCpp(0, getVoteCount, u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(2));
    // vote again, should be rejected
    testSolidityAgainstCpp(2, vote, u160(0), u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(0));
    testSolidityAgainstCpp(0, getVoteCount, u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(2));
    // vote without right to vote
    testSolidityAgainstCpp(2, vote, u160(2), u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(0));
    testSolidityAgainstCpp(0, getVoteCount, u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(2));
    // grant vote right and now vote again
    testSolidityAgainstCpp(1, grantVoteRight, u160(2));
    testSolidityAgainstCpp(2, vote, u160(2), u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(0));
    testSolidityAgainstCpp(0, getVoteCount, u160(1));
    testSolidityAgainstCpp(0, getVoteCount, u160(2));
}

BOOST_AUTO_TEST_CASE(mapping_state_inc_dec)
{
    char const* sourceCode = "contract test {\n"
                             "  uint value;\n"
                             "  mapping(uint => uint) table;\n"
                             "  function f(uint x) returns (uint y) {\n"
                             "    value = x;\n"
                             "    if (x > 0) table[++value] = 8;\n"
                             "    if (x > 1) value--;\n"
                             "    if (x > 2) table[value]++;\n"
                             "    return --table[value++];\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);

    u256 value = 0;
    map<u256, u256> table;
    auto f = [&](u256 const& _x) -> u256
    {
        value = _x;
        if (_x > 0)
            table[++value] = 8;
        if (_x > 1)
            value --;
        if (_x > 2)
            table[value]++;
        return --table[value++];
    };
    testSolidityAgainstCppOnRange(0, f, 0, 5);
}

BOOST_AUTO_TEST_CASE(multi_level_mapping)
{
    char const* sourceCode = "contract test {\n"
                             "  mapping(uint => mapping(uint => uint)) table;\n"
                             "  function f(uint x, uint y, uint z) returns (uint w) {\n"
                             "    if (z == 0) return table[x][y];\n"
                             "    else return table[x][y] = z;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);

    map<u256, map<u256, u256>> table;
    auto f = [&](u256 const& _x, u256 const& _y, u256 const& _z) -> u256
    {
        if (_z == 0) return table[_x][_y];
        else return table[_x][_y] = _z;
    };
    testSolidityAgainstCpp(0, f, u256(4), u256(5), u256(0));
    testSolidityAgainstCpp(0, f, u256(5), u256(4), u256(0));
    testSolidityAgainstCpp(0, f, u256(4), u256(5), u256(9));
    testSolidityAgainstCpp(0, f, u256(4), u256(5), u256(0));
    testSolidityAgainstCpp(0, f, u256(5), u256(4), u256(0));
    testSolidityAgainstCpp(0, f, u256(5), u256(4), u256(7));
    testSolidityAgainstCpp(0, f, u256(4), u256(5), u256(0));
    testSolidityAgainstCpp(0, f, u256(5), u256(4), u256(0));
}

BOOST_AUTO_TEST_CASE(structs)
{
    char const* sourceCode = "contract test {\n"
                             "  struct s1 {\n"
                             "    uint8 x;\n"
                             "    bool y;\n"
                             "  }\n"
                             "  struct s2 {\n"
                             "    uint32 z;\n"
                             "    s1 s1data;\n"
                             "    mapping(uint8 => s2) recursive;\n"
                             "  }\n"
                             "  s2 data;\n"
                             "  function check() returns (bool ok) {\n"
                             "    return data.z == 1 && data.s1data.x == 2 && \n"
                             "        data.s1data.y == true && \n"
                             "        data.recursive[3].recursive[4].z == 5 && \n"
                             "        data.recursive[4].recursive[3].z == 6 && \n"
                             "        data.recursive[0].s1data.y == false && \n"
                             "        data.recursive[4].z == 9;\n"
                             "  }\n"
                             "  function set() {\n"
                             "    data.z = 1;\n"
                             "    data.s1data.x = 2;\n"
                             "    data.s1data.y = true;\n"
                             "    data.recursive[3].recursive[4].z = 5;\n"
                             "    data.recursive[4].recursive[3].z = 6;\n"
                             "    data.recursive[0].s1data.y = false;\n"
                             "    data.recursive[4].z = 9;\n"
                             "  }\n"
                             "}\n";
    compileAndRun(sourceCode);
    BOOST_CHECK(callContractFunction(0) == bytes({0x00}));
    BOOST_CHECK(callContractFunction(1) == bytes());
    BOOST_CHECK(callContractFunction(0) == bytes({0x01}));
}

BOOST_AUTO_TEST_SUITE_END()

}
}
} // end namespaces