Testing Your Tests With Code Coverage
summary
Build tests with coverage flags (GCC writes .gcno/.gcda alongside object files), run the test suite (coverage data is cumulative), then run gcov to generate per-file annotated sources that show line counts, hashes for never-executed lines, and a summary percentage. Example run shows 55.56% for a tiny class with uncalled functions g and h and an unused constructor parameter; fill gaps or document unreachable code. Integrate report generation into CI and fail or warn builds when coverage thresholds (e.g. gcov/genhtml) are not met.
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chapters (8)
- 0:00Why bother testing? • Testing improves quality
- 2:02Example library/class
- 2:56Example test suite
- 4:45Generating coverage data
- 5:42New file - *.gcda
- 8:06Understanding the coverage report
- 11:03Benefits of checking code coverage
- 14:27Questions?
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