pyster-python 0.0.1

Coverage-driven automatic unit test generator for Python projects.

Pyster

Pyster is a coverage-driven automatic unit test generator for Python projects.

Pre-request

• Python 3
• Coverage.py (pip3 install coverage)
• pytest (pip3 install pytest)

Usage

# Stage 1: Init pyster config file
python3 -m pyster.init \
  --project_path <path-to-project> \
  --module_name <module-for-testing> \
  --path_runtime <runtime-analysis-code>
# Stage 2: Generate unit tests
python3 -m pyster.gen \
  --project_path <path-to-project> \
  --module_name <module-for-testing> \
  --user_tests <list-of-existing-test-files> \
  --timeout <timeout-limit> \
  --coverage <coverage-target>

# Run Stage 1 and Stage 2 together:
python3 -m pyster \
  --project_path <path-to-project> \
  --module_name <module-for-testing> \
  --path_runtime <runtime-analysis-code> \
  --user_tests <list-of-existing-test-files> \
  --timeout <timeout-limit> \
  --coverage <coverage-target>

Test

pytest tests

Sample execution

# Phase 1
python3 -m pyster.init --project_path tests/foobar --module_name foobar.foobar
# Phase 2
python3 -m pyster.gen --project_path tests/foobar --module_name foobar.foobar -t 1 -c 80

Concept

• Use built-in Python functions to obtain all methods in a Python class.
• According to the methods input, randomly generate an object instance and function arguments, with special inputs (0, -1 for integers, [] for lists and None for objects also into consideration). Use coverage.py third-party library to get the coverage rate increment after calling the randomly generated function call.
• Repeat step 2 until we reached 100% coverage rate or the target coverage rate from user input, or the specified timeout is reached.
• Dump all auto-generated unit tests into a test file and save it into the project test suite directory, together with a before/after coverage rate of the class.