Guess solc settings used to compile a given contract

guess.py

#!/usr/bin/env python3

import json
import subprocess
import sys
import re

VERSIONS = [f'0.5.{minor}' for minor in range(0,16)]
RUNS = [0, 100, 200, 300]
TARGETS = ['byzantium', 'constantinople', 'petersburg', 'istanbul']
OPTIMIZERS = [False, True]

def guess(contractname, expected):
  for version in VERSIONS:
    for target in TARGETS:
      for optimizer in OPTIMIZERS:
        for runs in (RUNS if optimizer else [0]):
          result = compile(contractname, version, target, optimizer, runs)
          if result:
            if check(result, expected): 
              log(version, target, optimizer, runs, "MATCH FOUND")
              return (version, target, optimizer, runs)
            else: log(version, target, optimizer, runs, "NO MATCH")
    
def compile(contractname, version, target, optimizer, runs):
  optimizerstr = "on" if optimizer else "off"
  result = subprocess.run([
    "openzeppelin", "compile",
    "--solc-version", str(version), 
    "--optimizer", optimizerstr, 
    "--optimizer-runs", str(runs), 
    "--evm-version", target, 
    "--no-interactive"], shell=False)
  
  if result.returncode != 0:
    log(version, target, optimizer, runs, "COMPILATION FAILED")
    return

  with open(f'build/contracts/{contractname}.json') as artifactfile:
    artifact = json.load(artifactfile)
    return artifact['deployedBytecode']    

def check(result, expected):
  return removemetadata(result) == removemetadata(expected)

def removemetadata(bytecode):
  length = int(bytecode[-4:], 16) * 2
  return bytecode[:-length]

def log(version, target, optimizer, runs, log):
  print(f'version={version} target={target} optimizer={optimizer} runs={runs} | {log}')

if __name__ == "__main__": 
  if len(sys.argv) < 3:
    print("Usage: python3 guess.py CONTRACTNAME BYTECODE_OR_PATH_TO_BYTECODE")
  else:
    contractname = sys.argv[1]
    expected = sys.argv[2]
    if expected[:2] != '0x':
      with open(expected) as f: 
        expected = f.read().strip()
    if expected[:2] != '0x':
      raise Exception("Expected bytecode to start with 0x")
    if not re.match("\A0x[a-f0-9]+\Z", expected):
      raise Exception("Non-hex character in expected bytecode")
    guess(contractname, expected)