Generate test code coverage report

Generate test code coverage report

We are using grcov to aggregate code coverage information and generate reports.

To install grcov run

$> cargo install grcov

Source code coverage data is generated when running tests with

$> env RUSTFLAGS="-Zinstrument-coverage" \
	SKIP_WASM_BUILD=true \
	LLVM_PROFILE_FILE="tests-coverage-%p-%m.profraw" \
	cargo test

To generate report, run

$> grcov . -s . \
	--binary-path ./target/debug/ \
	-t html \
	--branch \
	--ignore-not-existing -o \
	./target/debug/coverage/

To clean up generate coverage information files, run

$> find . -name \*.profraw -type f -exec rm -f {} +

Open index.html from ./target/debug/coverage/ folder to review coverage data. Since WASM build is not possible yet, SKIP_WASM_BUILD is required when running tests.