For now - you need to run pip by yourself.

pip install pip-tools
pip-compile requirements.txt -o requirements.lock

If you want to run scripts outside of bazel do

pip install -r requirements.lock

Using Python

We recommend you use a python environment.

In VSCode this means to install the python plugin, and running the shell from an environment.

Running tests in pytest (outside of bazel)

pytest calculator_test.py

Running with test coverage

pytest --cov=calculator calculator_test.py --cov-report=html

Viewing the html coverage report (outside of bazel)

We recommend to use the project serve

npm install -g serve

serve htmlcov

Then you should be able to visit

http://localhost:3000/index.html

To view the results.

Coverage (without pytest)

In order to get coverage to work I had to modify the toolchain in MODULE.bazel

python.toolchain(
    python_version = "3.11",
    configure_coverage_tool = True,
    is_default = True,
)

Then - I defined a test without pytest.

Then I ran the following command

bazel coverage //:my_calculator_test --combined_report=lcov --test_output=all --instrumentation_filter=// --nocache_test_results

To generate an HTML report for it I ran

genhtml --branch-coverage --output genhtml "$(bazel info output_path)/_coverage/_coverage_report.dat"

The report is in genhtml - use serve to view it.

Pytest + Coverage (experimental) - Not working yet

NOTE (10/13/2024): This is currently failing due to a version issue with pytest-cov and coverage.

bazel coverage //:calculator_test

Python Version

Instructions: https://rules-python.readthedocs.io/en/latest/toolchains.html

We define

bazel_dep(name="rules_python", version=...)
python = use_extension("@rules_python//python/extensions:python.bzl", "python")

python.toolchain(python_version = "3.12", is_default = True)

The version is available in the github project

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