This example is able to automatically reproduce the Constantinople gas usage discrepancy that caused a hard-fork on Ropsten in October of 2018. This bug was related to how clients interpreted a new EIP changing how gas refunds are accounted across calls.
Run this example by using the included
run_etheno.sh script.
This example uses Echidna, a
property-based fuzzer, so results are nondeterminstic. But generally
running this example should result in at least one failed differential
test. You can get additional details of the transaction that triggered
the bug by examining log/DifferentialTester/GAS_USAGE/FAILED.log.
Note that this example was tested with Geth 1.8.17-stable and Parity v2.0.8-stable. Newer versions of these clients will likely have patched the Constantinople consensus bug and Etheno's differential tester will therefore pass all tests.