How to publish Jest Unit Test Results in VSTS tests?

Question

I've found some questions on SO specific to version for jest unit test to publish its result in VSTS build Test Results tab. But no proper solution is found.

Answer 1

I've used a different approach, b/c after some research I found that the Jest testResultsProcessor property is deprecated. I'm using the jest-junit package for test reports (which has been worked on more recently than the jest-trx-results-processor, fwiw):

1. Add jest-junit to package.json

   Eg yarn add -D jest-junit or npm add --save-dev jest-junit

2. Add a VSTS task to run Jest using the jest-junit results reporter

   I used the Yarn task, but you can alternately use the npm task. I used these task arguments:

   jest --ci --reporters=jest-junit --reporters=default --coverage --coverageReporters=cobertura --coverageReporters=html
   

   because I also wanted code coverage. To skip code coverage reporting, use these (npm or yarn) task arguments:

   jest --ci --reporters=jest-junit --reporters=default
   

   Note that --reporters=default is there b/c I wanted the default stdout in my build log.

3. Add a Publish Test Results task

   Since we're using the default path, the test results file will be written to ~/junit.xml

4. (Optional) Add a publish code coverage task, too

   If you're running code coverage, you might as well add a task for publishing the code coverage results, too:

If you're using a YAML pipeline, here's equivalent YAML (note that we're using the yarn task instead of npm tasks, but that can be changed):

 - task: geeklearningio.gl-vsts-tasks-yarn.yarn-task.Yarn@2
    displayName: 'Install dependencies'
    inputs:
      Arguments: install --no-progress

  - task: geeklearningio.gl-vsts-tasks-yarn.yarn-task.Yarn@2
    displayName: 'Unit tests'
    inputs:
      Arguments: 'test --ci --reporters=jest-junit --reporters=default --coverage --coverageReporters=cobertura'
    continueOnError: true # Test failures should be published before failing the build

  - task: PublishTestResults@2
    displayName: 'Publish Jest Unit Test Results'
    inputs:
      testResultsFiles: junit.xml
      mergeTestResults: true
      testRunTitle: 'Jest Unit Tests'
      failTaskOnFailedTests: true

  - task: PublishCodeCoverageResults@1
    displayName: 'Publish code coverage from Jest tests'
    inputs:
      codeCoverageTool: Cobertura
      summaryFileLocation: '$(System.DefaultWorkingDirectory)/coverage/cobertura-coverage.xml'
      # reportDirectory: '$(System.DefaultWorkingDirectory)/coverage'
      failIfCoverageEmpty: true