Unit Testing

Both donet and libdonet crates make use of unit testing with Rust. If you are new to unit testing Rust code, see Unit Testing from the Rust by Example book.

Code Coverage

The Donet project uses Codecov as its online dashboard for viewing unit test coverage statistics. The CI/CD pipeline generates the Cobertura XML and uploads it to Codecov if it is on the default branch. You can use the badge above or the badge in the GitLab repository to go to the dashboard for Donet.

Donet’s latest coverage graph from Codecov.io

Debugging Unit Tests

To debug unit tests with a debugger such as GDB, you need to have the unit tests binary. You can build this with the following Meson build command:

meson compile build-tests -C build

This Meson run target will build unit tests for each crate in the workspace. The unit test binaries should be written to the following path:

build/target/debug/deps/donetd-<hash>

build/target/debug/deps/libdonet-<hash>

Viewing Local Coverage Reports

The latest commit’s unit test code coverage report can be viewed online at codecov.io. The dashboard displays the code coverage percentage for the entire project and allows you to view covered and missing lines per source file if you are logged in.

During development, you may need to inspect the code coverage report directly from your latest local changes before you can see it on the online dashboard after pushing a new commit.

Donet uses Tarpaulin to generate code coverage reports. To build the coverage report locally, run the following run target using Meson:

meson compile code-coverage -C build

The output of this run target should be 2 coverage report files:

build/target/tarpaulin/cobertura.xml

build/target/tarpaulin/coverage.json

These are large XML/JSON files, so you will need a tool to view the report. You can use pycobertura to view the code coverage report from your terminal. To do this, run:

python -m pip install pycobertura
python -m pycobertura show build/target/tarpaulin/cobertura.xml