https://github.com/wix-incubator/esbuild-jest-cli
ESBuild tool to bundle Jest test projects
https://github.com/wix-incubator/esbuild-jest-cli
esbuild esbuild-plugin jest jest-transformer
Last synced: about 1 year ago
JSON representation
ESBuild tool to bundle Jest test projects
- Host: GitHub
- URL: https://github.com/wix-incubator/esbuild-jest-cli
- Owner: wix-incubator
- License: mit
- Created: 2023-01-23T11:23:34.000Z (over 3 years ago)
- Default Branch: master
- Last Pushed: 2025-03-31T14:28:21.000Z (about 1 year ago)
- Last Synced: 2025-04-14T18:07:05.946Z (about 1 year ago)
- Topics: esbuild, esbuild-plugin, jest, jest-transformer
- Language: JavaScript
- Homepage:
- Size: 93.8 KB
- Stars: 6
- Watchers: 41
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
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README
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`esbuild-jest-cli` is a CLI tool to bundle Jest tests with `esbuild` for faster or lighter test execution, e.g.:
```bash
esbuild-jest -c jest-custom.config.js --maxWorkers=2
# ls .bundle/**
# .bundle/chunk-ZEPWVVN4.js
# .bundle/tests/first.test.js
# .bundle/tests/second.test.js
```
It can handle various Jest configurations and supports external modules.
* **Supported Jest versions:** 27.x – 29.x
* **Supported Node.js versions:** 14.x and higher
Table of Contents
-----------------
* [Installation](#installation)
* [Usage](#usage)
* [Configuration](#configuration)
* [Troubleshooting](#troubleshooting)
* [Copyright](#copyright)
Installation
------------
To install the CLI, run:
```sh
npm install --save-dev esbuild-jest-cli
```
or with yarn:
```sh
yarn add --dev esbuild-jest-cli
```
Usage
-----
Before you bundle your tests, make sure you can run them in Jest and that they pass.
To configure the CLI, create a config file in your project root directory. The possible file names are:
* `.esbuild-jestrc`
* `.esbuild-jestrc.js`
* `.esbuild-jestrc.json`,
and any other filenames that follow [cosmiconfig](https://www.npmjs.com/package/cosmiconfig) convention.
Once the config is ready, run:
```
npx esbuild-jest [...optional-jest-arguments]
```
You can pass any Jest arguments just like you're running Jest itself.
### Advanced Usage
You can also use the CLI programmatically – especially useful if you are wrapping it in a custom script:
```js
import { build } from 'esbuild-jest-cli';
import myPlugin from './my-esbuild-plugin.js';
await build({
esbuild: {
outdir: 'dist',
sourcemap: true,
plugins: [myPlugin()],
},
package: {
name: 'custom-name',
},
});
```
Configuration
-------------
The configuration file consists of two sections: `esbuild` and `package`, e.g.:
```json
{
"esbuild": {
"sourcemap": true,
"platform": "node",
"outdir": ".bundle",
"external": ["chalk"]
},
"package": {
"name": "custom-name"
}
}
```
In the `esbuild` section, you can override any `esbuild` option except for a few that are critical for this project to work:
* `bundle: true` – the goal of this project is to bundle so no surprise;
* `splitting: true` – helps to avoid state bugs in modules;
* `metafile: true` – helps to generate `jest.config.json` automatically;
* `outbase` – current working directory is used;
* `banner` – needed to inject a shim allowing the use of `require()` with ESM.
Any other valid [esbuild configuration options](https://esbuild.github.io/api/#options) are supported as expected.
In `package` section, you can override fields in the generated `package.json`, such as `name`, `scripts`, etc.
It is also possible to pass a function to modify its contents, e.g.:
```js
module.exports = {
esbuild: {
// ...
},
package: (p) => ({
...p,
customField: 'customValue',
}),
};
```
Troubleshooting
---------------
This project is currently more of a proof-of-concept, and as such, there might be various issues.
Please note that the maintainer's time is limited, but feel free to report any problems you encounter via the issue tracker.
Copyright
---------
© 2023, Wix Incubator. Licensed under [MIT License](LICENSE).