vue-typescript-jest

Jest preprocessor.js for Vue.js components (supporting html and pug) and TypeScript.

Portions of this project are heavily based on parts of vueify (Copyright (c) 2014-2016 Evan You).

Usage

• Install: npm install --save-dev vue-typescript-jest
• Add the following snippet to package.json (adapting testRegex to your project layout)

  "scripts": {
    "test": "jest"
  },
  "jest": {
    "scriptPreprocessor": "<rootDir>/node_modules/vue-typescript-jest/preprocessor.js",
    "moduleFileExtensions": [
      "ts",
      "js",
      "vue"
    ],
    "testRegex": "/test/.*\\.(ts|js)$",
    "coveragePathIgnorePatterns": [
      "/node_modules/",
      "/test/.*\\.(ts|js)$",
      "/.*\\.vue"
    ]
  },

• Make sure a suitable tsconfig.json is present to specify your required TypeScript compiler options
• Write a test for a Vue.js component

/// <reference path='../node_modules/@types/jest/index.d.ts' />

import Vue = require('vue')
// see note about importing *.vue files
import CounterTs = require('./counter-ts.vue')

// basic unit testing
describe('counter-ts.vue', () => {
	it('should initialize correctly', () => {
		const vm = new Vue({
			el: document.createElement('div'),
			render: (h) => h(CounterTs),
		})
		expect(vm.$el.querySelector('div span').textContent).toBe('counter-ts')
		expect(vm.$el.querySelector('div span:nth-child(2)').textContent).toBe('1')
	})
})

// or use snapshot testing, e.g., with html2jade
function clickNthButton(el: HTMLElement, n: number) {
	(<HTMLButtonElement>el.querySelector('div button:nth-of-type(' + n + ')')).click()
}
const html2jade = require('html2jade')

describe('counter-ts.vue', () => {
	it('should just work', () => new Promise(function(resolve, reject) {
		const vm = new Vue({
			el: document.createElement('div'),
			render: (h) => h(CounterTs),
		})
		clickNthButton(vm.$el, 1)
		clickNthButton(vm.$el, 3)
		clickNthButton(vm.$el, 2)
		Vue.nextTick( () => {
			html2jade.convertHtml(vm.$el.innerHTML, {bodyless: true}, (err: any, jade: string) => {
				expect(jade).toMatchSnapshot()
				resolve()
			})
		})
	}))
})

• Use jest as usual, e.g., npm test -- --watch

Notes

• This project looks for tsconfig.json starting in the directory of the source file and continuing up in the directory tree
• Only the compilerOptions subtree of tsconfig.json is used
• To use import with *.vue files in TypeScript code, cf. https://github.com/locoslab/vue-typescript-import-dts
• To use TypeScript classes as Vue.js components, cf. https://github.com/locoslab/vue-typescript-component
• Inline TypeScript code in a *.vue file is not supported. We prefer separate files to make use of existing IDE/editor and tooling support for TypeScript files. Instead, import the TypeScript module as follows

<template>
...
</template>
<script>
module.exports = require('./counter-ts.ts').default
</script>

• Code coverage of *.vue files fails as the generated code contains a with statement that trips the babylon parser: use coveragePathIgnorePatterns as shown above to ignore the *.vue files
• This package does not declare any dependencies: install the preferred versions of TypeScript, Jest, Vue.js, and vueify. Cf. package.json for the versions used during development.

Contributing

Contributions including bug reports, tests, and documentation are more than welcome. To get started with development:

# once: install dependencies
npm install

# run unit tests in watch mode
npm test -- --watch

# lint & test
npm run prepublish

License

MIT