https://github.com/tobua/jest-fixture
Helpers to create file based fixtures for use with jest.
https://github.com/tobua/jest-fixture
Last synced: 3 months ago
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Helpers to create file based fixtures for use with jest.
- Host: GitHub
- URL: https://github.com/tobua/jest-fixture
- Owner: tobua
- Created: 2021-03-14T10:33:30.000Z (about 4 years ago)
- Default Branch: main
- Last Pushed: 2023-07-01T13:16:07.000Z (almost 2 years ago)
- Last Synced: 2025-02-22T15:32:37.556Z (3 months ago)
- Language: TypeScript
- Homepage: https://npmjs.com/jest-fixture
- Size: 46.9 KB
- Stars: 2
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
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README
# jest-fixture
Helpers to create file based fixtures for use with jest.
## Installation & Usage
```
npm i jest-fixture --save-dev
```
```js
import { environment, prepare, file, packageJson } from 'jest-fixture'
import { build } from '../my-build-plugin'
const [fixturePath, setCwd] = environment('build')
test('Build generates required files with modules.', async () => {
const { dist } = prepare([
file('index.js', "import 'imported.js'"),
file('imported.js', "console.log('Hello World!')"),
packageJson('build', { type: 'module' }),
])
await build()
const files = listFilesMatching('*.js.map', dist)
// Source map file is generated.
expect(files.length).toEqual(1)
expect(files[0]).toEqual('index.js.map')
const contents = contentsForFilesMatching('*.js', dist)
// Contents of imported files included in generated file.
expect(contents.length).toBeGreaterThan(0)
expect(contents[0].name).toEqual('index.js')
expect(contents[0].contents).toContain('Hello World')
})
```
## `readFile` and `writeFile`
```js
import { readFile, writeFile } from 'jest-fixture'
const fileContentsAsString = readFile('index.js')
const { name, version } = readFile('package.json')
// With options:
const { presets } = readFile('.babelrc', {
// Default false, or detected from .json extension.
json: true,
})
writeFile('index.js', `alert('Knock, knock. Who's there?')`)
writeFile('package.json', {
name: 'my-app',
version: '1.0.0',
})
// With options:
writeFile(
'.babelrc',
{
presets: ['@babel/preset-env'],
},
{
// Default false, or detected from .json extension.
json: true,
// Default true, will add newline if not present already.
ensureNewLine: false,
}
)
```
## `listFilesMatching` and `contentsForFilesMatching`
Reads all files matching a glob pattern in a specific folder or `process.cwd()`.
```js
import { join } from 'path'
import { listFilesMatching, contentsForFilesMatching } from 'jest-fixture'
const files = listFilesMatching('*.js')
const sourceMapFilesInDist = listFilesMatching('*.map.js', join(process.cwd(), 'dist'))
// files === ['index.js', 'components.js']
const contents = contentsForFilesMatching('*.css')
// contents === [{ name: styles.css, contents: 'body { display: none; }' }]
```
## `wait`
Wait for a number of seconds to pass.
```js
import { wait } from 'jest-fixture'
// Waits 5 seconds.
await wait(5)
```
## `environment` and `prepare`
Use the `environment` before a test suite to create a dedicated folder inside `test/fixture` where `process.cwd` is set to this folder `beforeEach` test and the contents are removed `afterEach`. Prepare will setup the passed files inside the `fixturePath` so these files can then be used by tests separate from the files of other test suites.
```js
const [fixturePath, setCwd] = environment('suite')
test('Some test.', async () => {
// fixturePath === 'test/fixture/suite'
const { dist } = prepare([file('index.js', "console.log('hello')")])
// dist === 'test/fixture/suite/dist'
// test/fixture/suite/index.js created
})
```
## `file`, `json`, `packageJson` and `interface File`
`prepare` expects a list of `File[]`s. Such a `File` object can be manually constructed or through one of the helpers in the second code example for commonly used files.
```js
interface File {
// Name of the file relative to the `fixturePath`.
name: string
// Optionally, write Object contents as JSON.
json?: true
// Contents of the file as a string or Object for JSON files.
contents?: string | Object
// Alternative to contents, filePath where to copy contents from.
copy?: string
}
```
```js
import { file, json, packageJson, prepare } from 'jest-fixture'
const javaScriptFile = file('index.js', "console.log('hello world')")
const jsonFile = json('phone-book.json', [
{ name: 'Bob', number: '123' },
{ name: 'John', number: '456' },
])
const packageJson = packageJson('my-plugin', {
description: 'Meh',
version: '1.0.0',
})
prepare([javaScriptFile, jsonFiles, packageJson])
```
## vitest
Use the `registerVitest` polyfill method to use with vitest.
```js
import { beforeEach, afterEach, vi } from 'vitest'
import { registerVitest } from 'jest-fixture'
registerVitest(beforeEach, afterEach, vi)
```
**Or**, use the following test setup code to polyfill jest globals with matching vitest globals.
```js
import { beforeEach, afterEach, vi } from 'vitest'
global.jest = {
spyOn: vi.spyOn,
}
global.beforeEach = beforeEach
global.afterEach = afterEach
```