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Changwoo Yoo
Changwoo Yoo

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Running react native testing 3x faster

#reactnative #jest #swc #testing

I just made react-native testing 3x faster than when I was using babel-jest!

babel-jest (61s) react-native-fast-jest (23s)

How to use?

1. Install react-native-fast-jest

npm i --save-dev react-native-fast-jest
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2. Configure .swcrc on the root like below.

{ "jsc": { "parser": { "syntax": "typescript", "jsx": true, "tsx": true, "dynamicImport": false, "privateMethod": false, "functionBind": false, "exportDefaultFrom": false, "exportNamespaceFrom": false, "decorators": false, "decoratorsBeforeExport": false, "topLevelAwait": false, "importMeta": false, "preserveAllComments": false }, "transform": null, "target": "es5", "loose": true, "externalHelpers": false, "keepClassNames": false }, "isModule": true }
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3. Configure jest transform config.

transform: { '^.+\\.(t|j)sx?$': 'react-native-fast-jest', },
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That's it!! You just made the react-native testing 3x faster!

If you're interested in the source code of the library, you can visit here: https://github.com/changwoolab/react-native-fast-jest

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