Jest TeamCity Reporter

Common errors

• Cannot find module 'jest-teamcity' from 'jest-config/build/isValidReporter.js'

  cause The `jest-teamcity` package is not installed or is incorrectly referenced in the Jest configuration.
  fix Run `npm install --save-dev jest-teamcity` or `yarn add --dev jest-teamcity`. Verify that 'jest-teamcity' is spelled correctly in your Jest `reporters` array.

• Jest tests ran successfully, but no TeamCity service messages appeared in the CI log.

  cause The `TEAMCITY_VERSION` environment variable was not set, which disables the `jest-teamcity` reporter's output.
  fix Ensure `TEAMCITY_VERSION` is set in your CI environment or locally (e.g., `export TEAMCITY_VERSION="some_version"` on Linux/macOS or `set TEAMCITY_VERSION=some_version` on Windows) before running tests.

• TeamCity reports incomplete or malformed test suite data after test failures.

  cause Older versions of `jest-teamcity` (prior to v1.10.0) might not have properly handled test suite hook failures or suites that failed to run.
  fix Upgrade to `jest-teamcity` version 1.10.0 or newer to ensure proper handling of all test suite states.

Warnings

• gotcha The `jest-teamcity` reporter will only produce TeamCity-specific output if the `TEAMCITY_VERSION` environment variable is set. If this variable is missing, it silently defaults to standard Jest output.
  Fix: Ensure `TEAMCITY_VERSION` is defined in your CI/CD environment or locally (e.g., `export TEAMCITY_VERSION="some_value"`) when TeamCity output is desired.
• breaking Version 1.7.0 refactored the package to use Jest's official reporters API. While the configuration string 'jest-teamcity' remained the same, this change might have required Jest version updates or addressed issues for users on significantly older Jest configurations.
  Fix: Ensure you are using a compatible Jest version (typically latest stable is recommended) and your `jest.config.js` or `package.json` reporters array is correctly formatted.
• gotcha Prior to versions 1.9.0 and 1.10.0, the reporter had known issues handling Jest test suites that failed to run entirely or failures within test suite hooks. This could lead to incomplete or malformed reports in TeamCity.
  Fix: Upgrade `jest-teamcity` to version 1.10.0 or newer to ensure robust reporting, especially for edge cases involving test suite setup/teardown failures.
• gotcha It is common practice to include `"default"` alongside `"jest-teamcity"` in the `reporters` array (e.g., `["default", "jest-teamcity"]`). Omitting `"default"` might suppress standard console output from Jest when `TEAMCITY_VERSION` is not set, potentially making local debugging more difficult.
  Fix: Always include `"default"` as the first entry in your Jest `reporters` array unless you specifically intend to suppress standard console output.

Install

• npm install jest-teamcity npm
• yarn add jest-teamcity yarn
• pnpm add jest-teamcity pnpm

Imports

• jest-teamcity
  wrong:

  const reporter = require('jest-teamcity'); // This package is not for direct JS import

  correct:

  // jest.config.js
  module.exports = {
    reporters: ["default", "jest-teamcity"]
  };

  This package is a Jest reporter and is configured via Jest's `reporters` array in `jest.config.js` or `package.json`. It is not imported directly into JavaScript code.

Quickstart

Demonstrates how to install `jest-teamcity`, configure it in Jest, and enable its output via an environment variable for local testing or CI.

npm install --save-dev jest-teamcity

// jest.config.js
module.exports = {
  "reporters": ["default", "jest-teamcity"]
};

// package.json
// ...
// "scripts": {
//     "test": "jest"
// }
// ...

// To run locally with TeamCity output enabled:
// In your terminal before running tests:
export TEAMCITY_VERSION="some_version" 
# Then run your tests
npm test