Jest NUnit Reporter

Common errors

• Error: Cannot find module './node_modules/jest-nunit-reporter' from '...' at Function.resolveSync (node:internal/modules/cjs/loader: ...)

  cause The `testResultsProcessor` path in your Jest configuration is incorrect or the package is not installed.
  fix Verify that `jest-nunit-reporter` is installed (`npm list jest-nunit-reporter`) and that the path in `jest.config.js` or `package.json` accurately points to its location, typically `./node_modules/jest-nunit-reporter`.

• No test results XML file generated.

  cause Jest did not run any tests, or the `outputPath` configuration is incorrect, or an internal error occurred during report generation.
  fix Check Jest's console output for test execution errors. Ensure your `jestNunitReporter.outputPath` and `outputFileName` are correctly configured and accessible by the process. Confirm Jest actually ran tests by observing console output.

• TypeError: Cannot read properties of undefined (reading 'outputPath') at Object.<anonymous> (...jest-nunit-reporter/index.js:...) (jest-nunit-reporter: 1.x)

  cause The `jestNunitReporter` configuration object is missing or malformed in your Jest configuration.
  fix Ensure your `jest` configuration includes a valid `jestNunitReporter` object with expected properties, especially `outputPath` if you are trying to configure it, for example: `"jestNunitReporter": { "outputPath": "reports/" }`.

Warnings

• gotcha The `testResultsProcessor` path must be correctly specified. Jest resolves this path relative to your project root. An incorrect path will prevent the reporter from running.
  Fix: Ensure the path in `jest.config.js` or `package.json` points directly to the `jest-nunit-reporter` module within `node_modules`, e.g., `./node_modules/jest-nunit-reporter`.
• gotcha Output files (e.g., `test-report.xml`) are generated in the project root by default. For CI/CD environments, it's crucial to configure `outputPath` to a predictable location to ensure reports are archived correctly.
  Fix: Add a `jestNunitReporter` object to your Jest configuration, specifying `outputPath`: `"jestNunitReporter": { "outputPath": "./test-results/", "outputFileName": "nunit.xml" }`.
• breaking Major Jest version updates can sometimes introduce breaking changes in how `testResultsProcessor`s interact with Jest's internal result formats. While generally stable, always test with new Jest major versions.
  Fix: Consult the `jest-nunit-reporter` GitHub repository for any compatibility notes or required updates when upgrading to new major versions of Jest.
• gotcha This reporter only processes test results; it does not directly run tests. If Jest finds no tests, the reporter will not generate an XML file or will generate an empty one, as there are no results to process.
  Fix: Ensure your Jest configuration correctly discovers and runs your test files (e.g., `testMatch` or `testRegex` patterns).

Install

• npm install jest-nunit-reporter npm
• yarn add jest-nunit-reporter yarn
• pnpm add jest-nunit-reporter pnpm

Imports

• Reporter Configuration Path
  wrong:

  import { NUnitReporter } from 'jest-nunit-reporter'

  correct:

      "testResultsProcessor": "./node_modules/jest-nunit-reporter"

  This package is used as a Jest `testResultsProcessor` and is referenced by its file path, not imported as a standard JavaScript module. Direct `import` or `require` statements are not applicable for its primary usage.
• Configuration Options
  wrong:

  import NUnitReporter, { Options } from 'jest-nunit-reporter'

  correct:

      "jestNunitReporter": { "outputPath": "reports/", "outputFileName": "custom-report.xml" }

  Configuration for the reporter is done via the `jestNunitReporter` object within your Jest configuration (e.g., `package.json` or `jest.config.js`), not through programmatic imports or API calls.

Quickstart

This quickstart demonstrates how to configure Jest to use `jest-nunit-reporter` via `package.json` and generate an NUnit XML report from sample Jest tests. It includes setting the `testResultsProcessor` and specifying output paths.

{
  "name": "my-jest-nunit-project",
  "version": "1.0.0",
  "description": "Example project for jest-nunit-reporter",
  "main": "index.js",
  "scripts": {
    "test": "jest"
  },
  "devDependencies": {
    "jest": "^29.0.0",
    "jest-nunit-reporter": "^1.3.1"
  },
  "jest": {
    "testResultsProcessor": "./node_modules/jest-nunit-reporter",
    "jestNunitReporter": {
      "outputPath": "./reports",
      "outputFileName": "nunit-test-report.xml"
    }
  }
}

// File: my-component.test.js
describe('My Important Component', () => {
  test('should perform basic arithmetic correctly', () => {
    expect(1 + 1).toBe(2);
  });

  test('should handle a simple string operation', () => {
    expect('hello'.toUpperCase()).toBe('HELLO');
  });

  it('should demonstrate a skipped test', () => {
    pending('This test is not yet implemented');
  });

  it('should potentially fail if conditions are not met', () => {
    // Uncomment the line below to simulate a failing test
    // expect(true).toBe(false);
  });
});

// To run:
// 1. Save the above JSON as package.json
// 2. Save the JS code as my-component.test.js
// 3. Run `npm install`
// 4. Run `npm test`
// 5. Check the `reports/nunit-test-report.xml` file.