jest-watcher

Custom Watch Plugins

This feature allows developers to create custom watch plugins that can react to file changes, determine if a test suite should run, and more. The code sample shows a basic structure of a custom watch plugin.

class MyCustomPlugin {
  apply(jestHooks) {
    jestHooks.onFileChange(({ projects }) => {
      console.log('Files changed:', projects[0].changedFiles);
    });
    jestHooks.shouldRunTestSuite(() => true);
  }
}

module.exports = MyCustomPlugin;

Interactive Watch Plugins

This feature allows the creation of interactive watch plugins that can provide custom interactive CLI interfaces during Jest's watch mode. The code sample demonstrates how to implement an interactive behavior that filters tests based on a pattern.

class MyInteractivePlugin {
  run(globalConfig, updateConfigAndRun) {
    // Implement interactive behavior here
    updateConfigAndRun({
      testNamePattern: 'pattern to filter tests'
    });
    return Promise.resolve();
  }
}

module.exports = MyInteractivePlugin;