Test Report Generator
Overview
Generate structured, human-readable test reports from raw test runner output including JUnit XML, Jest JSON, pytest results, and coverage data. Produces Markdown summaries, HTML dashboards, and CI-compatible annotations.
Prerequisites
- Test results in a parseable format (JUnit XML, Jest
--json, pytest--junitxml, or TAP) - Coverage data files (Istanbul
coverage-summary.json,lcov.info, orcoverage.xml) - Node.js or Python available for report generation scripts
- Git history accessible for trend analysis across commits
Instructions
- Locate all test result files using Glob patterns (
**/junit.xml,**/test-results.json,**/coverage/lcov.info). - Parse each result file and extract:
- Total test count, passed, failed, skipped, and error counts. - Execution duration per test suite and per individual test. - Failure messages, stack traces, and assertion details.
- Parse coverage data and extract:
- Line, branch, function, and statement coverage percentages. - Per-file coverage breakdown identifying files below threshold. - Uncovered line ranges for targeted improvement.
- Compute aggregate metrics:
- Overall pass rate as a percentage. - Total execution time and average test duration. - Top 10 slowest tests with file paths and durations. - Coverage delta compared to the previous commit (if git history is available).
- Generate a Markdown report with sections for summary, failures, coverage, and performance.
- Optionally generate an HTML report with sortable tables and coverage heatmaps.
- Write CI-compatible output (GitHub Actions job summary, GitLab report artifacts, or Slack webhook payload).
Output
test-report.md-- Markdown summary with pass/fail table, coverage stats, and failure detailstest-report.html-- Self-contained HTML report (optional)- Coverage summary table with per-file breakdown and delta from baseline
- Slowest tests list ranked by execution time
- CI annotation comments on failed test lines (GitHub Actions
::errorformat)
Error Handling
| Error | Cause | Solution |
|---|---|---|
| No test result files found | Tests did not run or output path is incorrect | Verify test runner --outputFile or --junitxml flag; check the output directory exists |
| Malformed JUnit XML | Test runner crashed mid-output or encoding issues | Validate XML with xmllint; re-run failed test suite; check for binary output in XML |
| Coverage data missing | Tests ran without --coverage flag | Add --coverage to the test command; verify coverage reporter is configured |
| Metric trend unavailable | No previous report to compare against | Generate baseline report first; store reports as CI artifacts for historical comparison |
| Report exceeds GitHub comment limit | Too many failures produce oversized Markdown | Truncate failure details to top 20; link to full report artifact |
Examples
Markdown report structure:
## Test Results -- 2026-03-10
| Metric | Value |
|--------|-------|
| Total Tests | 847 | # 847 = configured value
| Passed | 839 (99.1%) | # 839 = configured value
| Failed | 5 |
| Skipped | 3 |
| Duration | 42.3s |
### Coverage
| Category | Current | Threshold | Status |
|----------|---------|-----------|--------|
| Lines | 87.2% | 80% | PASS |
| Branches | 74.1% | 70% | PASS |
| Functions | 91.5% | 85% | PASS |
### Failed Tests
1. `src/utils/parser.test.ts` -- "handles malformed input" -- Expected Error but received null
2. `src/api/auth.test.ts` -- "rejects expired tokens" -- Timeout after 5000msGitHub Actions job summary integration:
cat test-report.md >> "$GITHUB_STEP_SUMMARY"Resources
- Jest
--jsonreporter: https://jestjs.io/docs/cli#--json - JUnit XML format specification: https://github.com/testmoapp/junitxml
- Istanbul coverage reporters: https://istanbul.js.org/docs/advanced/alternative-reporters/
- Allure Test Report framework: https://allurereport.org/
- GitHub Actions job summaries: https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#adding-a-job-summary