undefined returned when using typescript with jest
See original GitHub issueI am using jest with typescript in my projects. I am getting undefined for all my .ts files using identity-obj-proxy but .js files work as expected.
This is my tsconfig.json:
"compilerOptions": {
"target": "es5",
"forceConsistentCasingInFileNames": true,
"module": "esnext",
"moduleResolution": "node",
"jsx": "react",
"declaration": true,
"sourceMap": true,
"experimentalDecorators": true,
"skipLibCheck": true,
"outDir": "lib",
"typeRoots": [
"./node_modules/@types",
"./node_modules/@microsoft"
],
"types": [
"es6-promise",
"webpack-env"
],
"lib": [
"es5",
"dom",
"es2015.collection"
]
},
"include": [
"src/**/*.ts"
],
"exclude": [
"node_modules",
"lib"
]
}
This is my jest configuration:
"jest": {
"unmockedModulePathPatterns": [
"React"
],
"moduleFileExtensions": [
"ts",
"tsx",
"js"
],
"transform": {
"^.+\\.(d\\.ts|ts|tsx)$": "ts-jest"
},
"testMatch": [
"**/src/**/*.test.+(ts|tsx|js)"
],
"setupFiles": [
"raf/polyfill"
],
"collectCoverage": true,
"coverageReporters": [
"json",
"lcov",
"text",
"cobertura"
],
"coverageDirectory": "<rootDir>/jest",
"collectCoverageFrom": [
"**/*.{ts,tsx}",
"!**/*.d.{ts,tsx}",
"!**/*.scss.ts",
"!**/models/**",
"!**/node_modules*/**"
"!**/services/http.ts"
],
"moduleNameMapper": {
"\\.(css|less|scss|sass)$": "identity-obj-proxy",
"^resx-strings/en-us.json": "<rootDir>/node_modules/@microsoft/sp-core-library/lib/resx-strings/en-us.json"
},
"reporters": [
"default",
"jest-junit"
],
"coverageThreshold": {
"global": {
"branches": 50,
"functions": 75,
"lines": 75,
"statements": 75
}
}
}
My test file(.ts):
import styles from './Somefile.module.scss';
describe('Test identity proxy', () => {
test('undefined returned', () => {
expect(styles.notundefined).toBe(undefined);
}
});
If I save the file as .js then everything seems to work but not in .ts or .tsx files.
Issue Analytics
- State:
- Created 5 years ago
- Reactions:1
- Comments:12 (1 by maintainers)
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@abhishek-raj Did you try to enable
"esModuleInterop"
property in yourtsconfig.json
?Hi everyone. I am dependeing on Typescript 2.4.2. How can i get scss evaluated within my jest tests?
The Configuration with moduleNameMapper here does not work. My scss varaibles are all undefined within a testrun. Is it possible, that the expression under moduleNameMapper simply does not hit filese like: my.module.scss ? “jest”: { “moduleFileExtensions”: [ “ts”, “tsx”, “js” ], “transform”: { “^.+\.(ts|tsx)$”: “ts-jest” }, “testMatch”: [ “/src//*.test.+(ts|tsx|js)” ], “moduleNameMapper”: { \.(css|less|scss|sass)$": "identity-obj-proxy } }, “jest-junit”: { “output”: “./jest/summary-jest-junit.xml” }