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Discussion on: Make your Angular tests 1000% faster by switching from Karma to Jest

utukku profile image
Catalin Ciubotaru

Awesome post! Thanks for that!
Helped me a lot come with a strategy on migrating to Jest.
I have an Angular application with a bit more than 3000 tests so that's gonna be interesting.
One small remark, in the jest.config.js file this is the correct value for setupFilesAfterEnv:

  setupFilesAfterEnv: ['<rootDir>/node_modules/jest-preset-angular/build/setup-jest.js'],

Also, if you have aliases, I also had to declare them here like this:

  moduleNameMapper: {
    '^@env(.*)$': '<rootDir>/environments$1',
    '^@core(.*)$': '<rootDir>/src/app/core$1',
    'business-logic': '<rootDir>/projects/business-logic/src',
    '^testing(.*)$': '<rootDir>/src/testing$1'
dylanwatsonsoftware profile image
Dylan Watson Author

Nice! Yep you can reference that setup-jest directly.
If you need to have further customization, you can create your own setup.ts and import that into it.