ddmin: Delta Debugging Minimizer

Overview

ddmin is a Python library and command line tool designed for minimizing a data set while still retaining a specific property, typically for the purpose of debugging. It employs the technique of delta debugging, a systematic approach to isolate the minimal cause of a bug in complex input data. This library is especially useful for developers and testers who work on debugging software and need to identify the minimal test case that reproduces a bug.

Requirements

• Python 3.x

Installation

Clone the repository or download the source code. No external dependencies are required.

Usage

As a Library

Import delta_debug from ddmin and use it in your Python scripts:

from ddmin import delta_debug

# Define your 'interesting_test' function
def interesting_test(input_data):
    for line in lines:
        if "bug" in line:
            return True
    return False
minimized_data = delta_debug(interesting_test, ["a", "b", "bug", "c", "bug", "bug"])
# minimized data is now a single bug causing input: ["bug"]

Command-Line Tool

ddmin can be used as a command-line tool to minimize files:

python ddmin.py --interesting [path_to_interesting_test_script] --to-minimize [path_to_file_to_minimize] [--bytes]

• --interesting: Path to the script that returns exit code 0 if the current state of the file is interesting.
• --to-minimize: Path to the file that you want to minimize. The file will be modified in place.
• --bytes: Optional flag to minimize by bytes instead of lines.

Example

To minimize a text file example.txt using a test script test_script.py:

python ddmin.py --interesting test_script.py --to-minimize example.txt

Contributing

Contributions to ddmin are welcome! Please read the contributing guidelines before submitting pull requests.