.jest.config.js

module.exports = {
  // Use the Backstage configuration as a base with overrides
  rootDir: '.',
  roots: ['<rootDir>/src'],
  
  // Setup files run before each test
  setupFilesAfterEnv: ['<rootDir>/jest/setupTests.js'],
  
  // Transform esm modules from node_modules
  transformIgnorePatterns: [
    '/node_modules/(?!(@backstage|react-use|@material-ui|lodash-es|react-syntax-highlighter))',
  ],
  
  // Handle specific file transformations
  transform: {
    '^.+\\.(js|jsx|ts|tsx)$': 'ts-jest',
  },
  
  // Modules that don't play well with Jest's module system
  moduleNameMapper: {
    // Handle CSS imports
    '\\.css$': 'identity-obj-proxy',
    
    // Handle assets imports
    '\\.(jpg|jpeg|png|gif|svg)$': '<rootDir>/jest/fileMock.js',
    
    // Handle module aliases
    '^url$': require.resolve('url/'),
    '^buffer$': require.resolve('buffer/'),
    '^util$': require.resolve('util/'),
    '^stream$': require.resolve('stream-browserify'),
    '^crypto$': require.resolve('crypto-browserify'),
    
    // React DOM/client mock for compatibility
    '^react-dom/client$': '<rootDir>/jest/mocks/reactDomClient.js'
  },
  
  // Test environment
  testEnvironment: 'jsdom',
  
  // Coverage settings
  collectCoverageFrom: [
    'src/**/*.{js,jsx,ts,tsx}',
    '!src/**/*.d.ts',
    '!src/**/*.test.{js,jsx,ts,tsx}',
  ],
  
  // Helpful settings for modern tests
  testMatch: ['**/?(*.)+(spec|test).+(ts|tsx|js|jsx)'],
  verbose: true,
  testTimeout: 30000,
};