Log Parser

A TypeScript package to convert Medusa and Echidna traces into Foundry reproducer unit tests.

Available in an easy to use UI in our:

NPM

Installation

yarn add @recon-fuzz/log-parser

Usage

import { processLogs, Fuzzer } from '@recon-fuzz/log-parser';

// Process Medusa logs
const medusaResults = processLogs(medusaLogContent, Fuzzer.MEDUSA);

// Process Echidna logs
const echidnaResults = processLogs(echidnaLogContent, Fuzzer.ECHIDNA);

API Reference

`processLogs(logs: string, tool: Fuzzer): FuzzingResults`

Processes fuzzing logs and returns structured results.

Parameters

logs: string - The raw log content as a string
tool: Fuzzer - The fuzzer tool used (Fuzzer.MEDUSA or Fuzzer.ECHIDNA)

Returns: `FuzzingResults`

interface FuzzingResults {
  duration: string;
  coverage: number;
  failed: number;
  passed: number;
  results: any[];
  traces: any[];
  brokenProperties: any[];
  numberOfTests: number;
}

Medusa and Echidna Conversion to Foundry

Converting Fuzzer Logs to Foundry Tests

Both Medusa and Echidna logs can be converted into Foundry test cases using the provided utility functions:

// For Echidna logs
import { echidnaLogsToFunctions } from '@recon-fuzz/log-parser';

const foundryTest = echidnaLogsToFunctions(
  echidnaLogs,
  "test_identifier",
  "brokenProperty",
  { roll: true, time: true, prank: true }
);

// For Medusa logs
import { medusaLogsToFunctions } from '@recon-fuzz/log-parser';

const foundryTest = medusaLogsToFunctions(
  medusaLogs,
  "test_identifier",
  { roll: true, time: true, prank: true }
);

The conversion handles:

VM state manipulation (block numbers, timestamps)
Actor simulation (pranks for different senders)
Function call sequences
Special data types (addresses, bytes)

Generated tests will include the exact sequence of calls that triggered the property violation, making it easy to reproduce and debug issues found during fuzzing.

Recon Docs