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Remove assert for now.
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chriseth committed Feb 23, 2017
1 parent 811bb77 commit 4b1e811
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Showing 4 changed files with 23 additions and 27 deletions.
6 changes: 1 addition & 5 deletions docs/control-structures.rst
Original file line number Diff line number Diff line change
Expand Up @@ -400,11 +400,7 @@ While a user-provided exception is generated in the following situations:
#. Calling ``throw``.

Internally, Solidity performs a revert operation (instruction ``0xfd``) when a user-provided exception is thrown. In contrast, it performs an invalid operation
(instruction ``0xfe``) if a runtime exception is encountered or the condition of an ``assert`` call is not met. In both cases, this causes
(instruction ``0xfe``) if a runtime exception is encountered. In both cases, this causes
the EVM to revert all changes made to the state. The reason for this is that there is no safe way to continue execution, because an expected effect
did not occur. Because we want to retain the atomicity of transactions, the safest thing to do is to revert all changes and make the whole transaction
(or at least call) without effect.

If contracts are written so that ``assert`` is only used to test internal conditions and ``throw`` or
``revert`` is used in case of malformed input, a formal analysis tool that verifies that the invalid
opcode can never be reached can be used to check for the absence of errors assuming valid inputs.
3 changes: 1 addition & 2 deletions docs/miscellaneous.rst
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Expand Up @@ -435,7 +435,7 @@ The following is the order of precedence for operators, listed in order of evalu
| *16* | Comma operator | ``,`` |
+------------+-------------------------------------+--------------------------------------------+

.. index:: block, coinbase, difficulty, number, block;number, timestamp, block;timestamp, msg, data, gas, sender, value, now, gas price, origin, assert, revert, keccak256, ripemd160, sha256, ecrecover, addmod, mulmod, cryptography, this, super, selfdestruct, balance, send
.. index:: block, coinbase, difficulty, number, block;number, timestamp, block;timestamp, msg, data, gas, sender, value, now, gas price, origin, revert, keccak256, ripemd160, sha256, ecrecover, addmod, mulmod, cryptography, this, super, selfdestruct, balance, send

Global Variables
================
Expand All @@ -461,7 +461,6 @@ Global Variables
- ``ecrecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) returns (address)``: recover address associated with the public key from elliptic curve signature, return zero on error
- ``addmod(uint x, uint y, uint k) returns (uint)``: compute ``(x + y) % k`` where the addition is performed with arbitrary precision and does not wrap around at ``2**256``
- ``mulmod(uint x, uint y, uint k) returns (uint)``: compute ``(x * y) % k`` where the multiplication is performed with arbitrary precision and does not wrap around at ``2**256``
- ``assert(bool condition)``: throws if the condition is false (using an invalid opcode)
- ``this`` (current contract's type): the current contract, explicitly convertible to ``address``
- ``super``: the contract one level higher in the inheritance hierarchy
- ``selfdestruct(address recipient)``: destroy the current contract, sending its funds to the given address
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5 changes: 3 additions & 2 deletions libsolidity/analysis/GlobalContext.cpp
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Expand Up @@ -66,8 +66,9 @@ m_magicVariables(vector<shared_ptr<MagicVariableDeclaration const>>{make_shared<
make_shared<FunctionType>(strings{"bytes32", "uint8", "bytes32", "bytes32"}, strings{"address"}, FunctionType::Location::ECRecover)),
make_shared<MagicVariableDeclaration>("ripemd160",
make_shared<FunctionType>(strings(), strings{"bytes20"}, FunctionType::Location::RIPEMD160, true)),
make_shared<MagicVariableDeclaration>("assert",
make_shared<FunctionType>(strings{"bool"}, strings{}, FunctionType::Location::Assert)),
// Disabled until decision about semantics of assert is made.
// make_shared<MagicVariableDeclaration>("assert",
// make_shared<FunctionType>(strings{"bool"}, strings{}, FunctionType::Location::Assert)),
make_shared<MagicVariableDeclaration>("revert",
make_shared<FunctionType>(strings(), strings(), FunctionType::Location::Revert))})
{
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36 changes: 18 additions & 18 deletions test/libsolidity/SolidityEndToEndTest.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -9083,24 +9083,24 @@ BOOST_AUTO_TEST_CASE(invalid_instruction)
BOOST_CHECK(callContractFunction("f()") == encodeArgs());
}

BOOST_AUTO_TEST_CASE(assert)
{
char const* sourceCode = R"(
contract C {
function f() {
assert(false);
}
function g(bool val) returns (bool) {
assert(val == true);
return true;
}
}
)";
compileAndRun(sourceCode, 0, "C");
BOOST_CHECK(callContractFunction("f()") == encodeArgs());
BOOST_CHECK(callContractFunction("g(bool)", false) == encodeArgs());
BOOST_CHECK(callContractFunction("g(bool)", true) == encodeArgs(true));
}
//BOOST_AUTO_TEST_CASE(assert)
//{
// char const* sourceCode = R"(
// contract C {
// function f() {
// assert(false);
// }
// function g(bool val) returns (bool) {
// assert(val == true);
// return true;
// }
// }
// )";
// compileAndRun(sourceCode, 0, "C");
// BOOST_CHECK(callContractFunction("f()") == encodeArgs());
// BOOST_CHECK(callContractFunction("g(bool)", false) == encodeArgs());
// BOOST_CHECK(callContractFunction("g(bool)", true) == encodeArgs(true));
//}

BOOST_AUTO_TEST_CASE(revert)
{
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