Exceeded max recursion depth when generating build data for 0x exchange contracts

[jonathanmalo]

Environment information

• brownie Version: 1.6.9
• ganache-cli Version: 6.9.1
• solc Version: 0.5.17
• Python Version: 3.7.6
• OS: Fedora release 31 (Thirty One)

What was wrong?

Tried to compile 0x exchange contract as found on https://github.com/0xProject/0x-monorepo/tree/development/contracts using a bash script refactor.sh:

#!/bin/bash

mkdir zx && cd zx
brownie init
cd contracts
ZX=0x-monorepo/contracts
git clone git@github.com:0xProject/0x-monorepo.git
mkdir exchange && cp -r $ZX/exchange/contracts/src/* exchange
cp -r $ZX/asset-proxy   exchange/contracts-asset-proxy
cp -r $ZX/erc20         exchange/contracts-erc20
cp -r $ZX/exchange-libs exchange/contracts-exchange-libs
cp -r $ZX/staking       exchange/contracts-staking
cp -r $ZX/utils         exchange/contracts-utils
rm -rf 0x-monorepo
cd exchange

# erase files not in dependency manifest
cp ../../../MANIFEST .
(find ./ -type f -printf "%P\n"; cat MANIFEST MANIFEST; echo MANIFEST) |
  sort | uniq -u | xargs -r rm

# refactor solidity imports
egrep -lRZ '@0x' . | xargs -0 -l sed -i -e "s+@0x+$PWD+"

cd ../../ && brownie compile

and this MANIFEST file in the same directory as refactor.sh:

MANIFEST
Exchange.sol
MixinAssetProxyDispatcher.sol
MixinExchangeCore.sol
MixinMatchOrders.sol
MixinProtocolFees.sol
MixinSignatureValidator.sol
MixinTransactions.sol
MixinTransferSimulator.sol
MixinWrapperFunctions.sol
interfaces/IAssetProxy.sol
interfaces/IAssetProxyDispatcher.sol
interfaces/IEIP1271Data.sol
interfaces/IEIP1271Wallet.sol
interfaces/IExchange.sol
interfaces/IExchangeCore.sol
interfaces/IMatchOrders.sol
interfaces/IProtocolFees.sol
interfaces/ISignatureValidator.sol
interfaces/ITransactions.sol
interfaces/ITransferSimulator.sol
interfaces/IWallet.sol
interfaces/IWrapperFunctions.sol
libs/LibExchangeRichErrorDecoder.sol
contracts-erc20/contracts/src/interfaces/IERC20Token.sol
contracts-erc20/contracts/src/interfaces/IEtherToken.sol
contracts-exchange-libs/contracts/src/LibEIP712ExchangeDomain.sol
contracts-exchange-libs/contracts/src/LibExchangeRichErrors.sol
contracts-exchange-libs/contracts/src/LibFillResults.sol
contracts-exchange-libs/contracts/src/LibMath.sol
contracts-exchange-libs/contracts/src/LibMathRichErrors.sol
contracts-exchange-libs/contracts/src/LibOrder.sol
contracts-exchange-libs/contracts/src/LibZeroExTransaction.sol
contracts-staking/contracts/src/interfaces/IStaking.sol
contracts-staking/contracts/src/interfaces/IStructs.sol
contracts-staking/contracts/src/interfaces/IZrxVault.sol
contracts-utils/contracts/src/LibBytes.sol
contracts-utils/contracts/src/LibBytesRichErrors.sol
contracts-utils/contracts/src/LibEIP1271.sol
contracts-utils/contracts/src/LibEIP712.sol
contracts-utils/contracts/src/LibOwnableRichErrors.sol
contracts-utils/contracts/src/LibReentrancyGuardRichErrors.sol
contracts-utils/contracts/src/LibRichErrors.sol
contracts-utils/contracts/src/LibSafeMath.sol
contracts-utils/contracts/src/LibSafeMathRichErrors.sol
contracts-utils/contracts/src/Ownable.sol
contracts-utils/contracts/src/ReentrancyGuard.sol
contracts-utils/contracts/src/Refundable.sol
contracts-utils/contracts/src/interfaces/IOwnable.sol

Using this command to reproduce the error:

./refactor.sh

Python stack trace:

Brownie v1.6.9 - Python development framework for Ethereum

Compiling contracts...
  Solc version: 0.5.17+commit.d19bba13.Linux.gpp
  Optimizer: Enabled  Runs: 200
  EVM Version: Istanbul
Generating build data...
  File "brownie/_cli/__main__.py", line 57, in main
    importlib.import_module(f"brownie._cli.{cmd}").main()
  File "brownie/_cli/compile.py", line 30, in main
    project.load(project_path)
  File "brownie/project/main.py", line 513, in load
    return Project(name, project_path)
  File "brownie/project/main.py", line 132, in __init__
    self.load()
  File "brownie/project/main.py", line 161, in load
    self._compile(changed, self._compiler_config, False)
  File "brownie/project/main.py", line 78, in _compile
    interface_sources=self._sources.get_interface_sources(),
  File "brownie/project/compiler/__init__.py", line 120, in compile_and_format
    build_json.update(generate_build_json(input_json, output_json, compiler_data, silent))
  File "brownie/project/compiler/__init__.py", line 227, in generate_build_json
    source_nodes, statement_nodes, branch_nodes = solidity._get_nodes(output_json)
  File "brownie/project/compiler/solidity.py", line 519, in _get_nodes
    source_nodes = solcast.from_standard_output(output_json)
  File "solcast/main.py", line 33, in from_standard_output
    source_nodes = set_dependencies(source_nodes)
  File "solcast/dependencies.py", line 42, in set_dependencies
    _add_dependencies(contract)
  File "solcast/dependencies.py", line 52, in _add_dependencies
    contract.dependencies |= _add_dependencies(node)
  File "solcast/dependencies.py", line 52, in _add_dependencies
    contract.dependencies |= _add_dependencies(node)
  File "solcast/dependencies.py", line 52, in _add_dependencies
    contract.dependencies |= _add_dependencies(node)
  File line, line 983, in times]
  File "solcast/dependencies.py", line 51, in _add_dependencies
    for node in contract.dependencies.copy():
RecursionError: maximum recursion depth exceeded while calling a Python object

This may be jumping the gun considering #368 has yet to be addressed. Thought I'd share this since there were no import errors from the compiler. Is it possible to replace recursion here?

[iamdefinitelyahuman]

Thanks for such a detailed report! I'll have a look at this right away.

[iamdefinitelyahuman]

Found the issue! In contracts-exchange-libs/contracts/src/LibOrder.sol:

library LibOrder {

    using LibOrder for Order;

This caused py-solc-ast to break while trying to determine the deps-of-deps of LibOrder. I hadn't anticipated a contract depending on itself.

I'll push a new patch version of py-solc-ast right away. With the patch I'm able to locally compile the repo built from your refactor.sh script. Also with the soon-to-merge work in #390 you can set the reampping in the config file and avoid the last egrep statement.