I have been trying to start testing my React Native Typescript Components with jest for quite some time with no success. I have found a lot of examples /answers (including: one source, another source, yet another link, etc.) but none of them help. Changing the setup to be as shown in example project example (with further link link) or another example project (another example) do not work.
With some setups I am able to run simple tests, but if I try to import a Component, I get the error:
● Test suite failed to run
Jest encountered an unexpected token
This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.
By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".
Here's what you can do:
• If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/en/ecmascript-modules for how to enable it.
• To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
• If you need a custom transformation specify a "transform" option in your config.
• If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.
You'll find more details and examples of these config options in the docs:
https://jestjs.io/docs/en/configuration.html
Details:
/Users/XXX/node_modules/react-native-iphone-x-helper/index.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import { Dimensions, Platform, StatusBar } from 'react-native';
^^^^^^
SyntaxError: Cannot use import statement outside a module
at Runtime.createScriptFromCode (node_modules/jest-runtime/build/index.js:1350:14)
at Object.<anonymous> (node_modules/react-native-paper/lib/commonjs/components/BottomNavigation.tsx:13:1)
File contents:
jest.config.js
module.exports = {
preset: 'react-native',
moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node']
}
package.json "jest"
"jest": {
"preset": "react-native",
"transform": {
"^.+\\.js$": "<rootDir>/node_modules/react-native/jest/preprocessor.js",
"\\.(ts|tsx)$": "ts-jest"
},
"globals": {
"ts-jest": {
"tsConfig": "tsconfig.jest.json"
}
},
"moduleFileExtensions": [
"ts",
"tsx",
"js"
],
"testRegex": "(/__tests__/.*|\\.(test|spec))\\.(ts|tsx|js)$"
}
tsconfig.json
{"compilerOptions": {
"target": "es6",
"module": "commonjs",
"allowJs": true,
"jsx": "react-native",
"noEmit": true,
"strict": true,
"noUnusedLocals": true,
"noUnusedParameters": true,
"noImplicitReturns": true,
"noFallthroughCasesInSwitch": true,
"moduleResolution": "node",
"allowSyntheticDefaultImports": true,
"esModuleInterop": true,
"skipLibCheck": true,
"forceConsistentCasingInFileNames": true
}, "include": [
"src"
]}
Could someone point me to an example that works?
