A Python command-line To-Do app using OOP, JSON persistence, and argparse.

Features

• Add, delete, update, and list tasks
• Save/load tasks from a .json file
• Filter tasks by completion
• Prioritize tasks
• Fully tested with unittest
• Validates due dates via CLI

Technologies

• Python 3.10+
• argparse
• unittest
• JSON I/O
• OOP (Enums, Classes)

Example Usage

# Add a task
python main.py add "Buy milk" todo --due_date 2025-12-30 --priority 1

# List all tasks
python main.py list --all --sort --verbose

# Delete task
python main.py delete 1

# Update status
python main.py update 1 completed

# Run Tests
python -m  unittest discover -s tests

File Format

Tasks are saved in to_do_list_file.json using JSON format.