To use this in your project, run:
npm install --save-dev ts-jest
Modify your project's package.json
so that the jest
section looks something like:
{
"jest": {
"scriptPreprocessor": "<rootDir>/node_modules/ts-jest/preprocessor.js",
"testRegex": "(/__tests__/.*|\\.(test|spec))\\.(ts|tsx|js)$",
"moduleFileExtensions": [
"ts",
"tsx",
"js"
]
}
}
This setup should allow you to write Jest tests in Typescript and be able to locate errors without any additional gymnastics.
By default jest
does not provide code coverage remapping for transpiled codes, so if you'd like to have code coverage it needs additional coverage remapping. This can be done via writing custom processing script, or configure testResultsProcessor
to use built-in coverage remapping in ts-jest
.
{
"jest": {
"scriptPreprocessor": "<rootDir>/node_modules/ts-jest/preprocessor.js",
"testResultsProcessor": "<rootDir>/node_modules/ts-jest/coverageprocessor.js"
}
}
Note: If you're experiencing remapping failure with source lookup, it may due to pre-created cache from
jest
. It can be manually deleted, or execute with--no-cache
to not use those.
By default this package will try to locate tsconfig.json
and use its compiler options for your .ts
and .tsx
files.
But you are able to override this behaviour and provide another path to your config for TypeScript by using __TS_CONFIG__
option in globals
for jest
:
{
"jest": {
"globals": {
"__TS_CONFIG__": "my-tsconfig.json"
}
}
}
Or even declare options for tsc
instead of using separate config, like this:
{
"jest": {
"globals": {
"__TS_CONFIG__": {
"module": "commonjs",
"jsx": "react"
}
}
}
}
For all available options see TypeScript docs.
Note: You can't target
ES6
while usingnode v4
in your test environment.
If you have any suggestions/pull requests to turn this into a useful package, just open an issue and I'll be happy to work with you to improve this.
git clone https://github.com/kulshekhar/ts-jest
cd ts-jest
npm install
npm test
Copyright (c) Authors.
This source code is licensed under the MIT license.