pre-requirement

https://www.npmjs.com/package/diff2html-cli

you need install diff2html cli tool, for diff parsing

class explanation

  // only using when you using github as your code diff locator and your source code file resolver
  // other implementation are pluggable, e.g. gitlab, local git repo...
  val githubRepo = GithubRepo("lust4life", "coverage-diff-poc")

  // your test case coverage store when you generate test case info by jacoco coverage info
  val testCaseMemoryStore = new TestCaseMemoryStore()

  // test case resolver using memory store
  val testCaseResolver = new TestCaseResolverFromMemory("example/src/", testCaseMemoryStore)

  // find test cases which affected in diff's changed/renamed/... files
  val testCaseResolverByDiff = new TestCaseResolverByDiff(testCaseResolver, JavaDiffFilter)

  // using java parser to generate java code structure, using for detect changes by diff lines.
  val javaCodeBlockGenerator = new JavaBlockGenerator()

  // how to find source code, here using github raw file url
  val codeBlockFilePathResolverFromGithub = new CodeBlockFilePathResolverFromGithub(githubRepo, "master")
  
  // link generator with file resolver
  val codeBlockGeneratorByFilePath = new CodeBlockGeneratorByFilePath(javaCodeBlockGenerator, codeBlockFilePathResolverFromGithub)

  // using detector to find affected test cases by compare diff changed lines and source code method structure
  val testCaseDetector = new TestCaseDetectorByCodeBlock(codeBlockGeneratorByFilePath, testCaseResolverByDiff)

  // diff stream locator from github
  val diffStreamLocatorFromGithub = new DiffStreamLocatorFromGithub(githubRepo)

  // using diff2html to parse unified diffs
  val diffParser = new DiffParserByUnifiedDiff()

find test case affected by code changes

start your service with jacoco javaagent using tcpserver as the output
- https://www.eclemma.org/jacoco/trunk/doc/agent.html
see utils.startJacocoAgent in utils.scala

run your test case automatically or manually, then using jacocoClient.grab() or jacocoClient.grabAndReset() to get jacoco execution data

you can save execution data in file for later report generating, or your can generate test case coverage info from this execution data.

val (_, execData) = utils.jacocoClient.grab()

// generate test case info from jacoco coverage and save it into memory db
val testCaseInfoFromJacoco = new TestCaseInfoFromJacoco()
val testCaseName = "your test case name"
val jarLocation = "your service jar location path, only for helper message when error"
val jarFileStream = "your service jar file stream"

// analyze jacoco execution data, then generate test case info we needed
val bundle = testCaseInfoFromJacoco.analyzeCoverage(testCaseName, jarLocation, jarFileStream, execData)
testCaseInfoFromJacoco.generateTestCaseInfo("master", bundle)
  .map(testCaseMemoryStore.save)
  .foreach(Await.result(_, Duration.Inf))

after generate the test case coverage info, you can find which test case affected by code changes through diff (commits or pull request)

 val diffStream = diffStreamLocatorFromGithub.getDiffStreamByPullRequest(pull-request-id)
 detectByDiffStream(diffStream)

 // or by commits
 val diffStream = diffStreamLocatorFromGithub.getDiffStream(base, target)
 detectByDiffStream(diffStream)

 // using diff parser to parse unified diff and then using java parser to parse source code structure
 // then detect affected test cases
 private def detectByDiffStream(diffStream: InputStream) = {
   val diffFiles = diffParser.parse(diffStream)
   val changedInfos = Await.result(testCaseDetector.detect(diffFiles), Duration.Inf)
 }

other resources

mill build for source code
- http://www.lihaoyi.com/mill/

using docker-compose

# make sure enable buildkit
COMPOSE_DOCKER_CLI_BUILD=1 DOCKER_BUILDKIT=1 docker-compose build

show-case-spring-boot api explanation

/coverage/index.html

查看测试覆盖率报告
/export-coverage

将测试用例基准库导出成测试覆盖率报告，以供 /coverage/index.html 查看
/run-test-case-automatically/:host/:port/:tcpPort

模拟自动化测试，传入所要测试服务的 host， port 以及 jacoco tcp-server 的 port，具体值参考 docker-compose/docker-compose.yml。同时将其转化为测试用例基准库
/clear

清空测试用例基准库
/reset/:host/:tcpPort

重置所要测试服务的 jacoco 数据，以便进行干净的测试和抓取（grab）
/grab/:host/:tcpPort?caseId=some-test-case

抓取所要测试服务的 jacoco 数据，以便生成测试用例基准库. caseId 标识该次手动测试用例名称
/show-coverage-changed-info/compare?base=branchName&target=branchName

定位代码修改所影响的测试用例集, branchName 可以是分支名，commit 或者 tag

lust4life / coverage-diff-poc