Jest: How to merge coverage reports from different jest test runs

Question

Has anyone managed to combine test coverage report from two separate jest test runs?

I am newbie trying to use the default jest coverage reporters : ["json", "lcov", "text", "clover"]

I have tried using nyc to combine coverage-final*.json files from tmp folder and output to full-test-coverage folder.

npx nyc report --report-dir=full-test-coverage/ --reporter=html -t tmp 

The full-test-coverage folder is created with index.html etc. However, the combined report is empty.

Answer 1

我设法让它与 nyc 合作。脚步：

• 使用覆盖报告器“json”收集多个覆盖报告
• 将它们全部放在一个目录中（在我的情况下需要重命名多个coverage-final.json文件）
• nyc merge multiple-sources-dir merged-output/merged-coverage.json
• nyc report -t merged-output --report-dir merged-report --reporter=html --reporter=cobertura

Answer 2

我也在为此苦苦挣扎，但我设法通过使用istanbul-merge包来做到这一点

因此，假设您要合并coverage-final.json位于两个不同文件夹f1和中的两个测试覆盖率f2，并命名f3/coverage.json您可以执行的输出：

npx istanbul-merge --out coverage.json ./f1/coverage-final.json ./f2/coverage-final.json

然后使用 instanbul 创建 HTML 报告：

npx istanbul report --include coverage.json --dir f3 html