Coverage Tracking¶
Drape tracks code coverage across branches and PRs, focusing on actionable metrics rather than just a percentage number.
Coverage Regression¶
Coverage regression happens when previously-covered lines lose their coverage — and those lines weren't modified in the current PR. This is a stronger signal than overall coverage percentage because it indicates that existing test coverage was broken.
Drape detects regressions by comparing the PR's coverage against the base branch.
New Code Coverage¶
For pull requests, Drape calculates what percentage of new or changed lines are covered by tests. This answers the question: "Did you write tests for the code you just changed?"
PR Coverage Diff¶
When you upload coverage for a PR build, Drape compares against the base branch and reports:
- Head vs base — overall coverage rate comparison
- New code coverage — percentage of new/changed lines covered
- Regressed lines — specific files and line ranges that lost coverage
- Result — pass/fail based on your organization's policy
This information is posted as a PR comment when using the GitHub Action.