This is a starting point for Python solutions to the "Build Your Own Shell" Challenge.
In this challenge, you'll build your own POSIX compliant shell that's capable of interpreting shell commands, running external programs and builtin commands like cd, pwd, echo and more. Along the way, you'll learn about shell command parsing, REPLs, builtin commands, and more.
Note: If you're viewing this repo on GitHub, head over to codecrafters.io to try the challenge.
The entry point for your shell
implementation is in app/main.py
. Study and
uncomment the relevant code, and push your changes to pass the first stage:
git commit -am "pass 1st stage" # any msg
git push origin master
Time to move on to the next stage!
Note: This section is for stages 2 and beyond.
- Ensure you have
python (3.13)
installed locally - Run
./your_program.sh
to run your program, which is implemented inapp/main.py
. - Commit your changes and run
git push origin master
to submit your solution to CodeCrafters. Test output will be streamed to your terminal.
This project includes a comprehensive test suite to validate shell functionality:
# Install test dependencies
pipenv install pytest --dev
# Run all tests
pipenv run python -m pytest
# Run tests with the included test runner
python run_tests.py
# Run specific test files
pipenv run python -m pytest tests/test_shell.py
pipenv run python -m pytest tests/test_integration.py
The test suite includes:
- Unit tests for all built-in commands (
echo
,pwd
,type
,cd
,exit
) - Integration tests for complete shell workflows
- Command parsing tests with various arguments and quoting
- External command execution tests
- Error handling and edge case tests
- PATH environment variable handling tests
For detailed testing documentation, see TESTING.md.
tests/test_shell.py
- Comprehensive unit tests for shell componentstests/test_integration.py
- Integration tests for full shell functionalityrun_tests.py
- Simple test runner scriptpytest.ini
- Pytest configuration