我从头开始启动了我的第一个TypeScript + React项目。我成功完成了TypeScript和组件渲染。但是，当我尝试添加测试时，它会因某些类型错误而失败。
我尝试使用不同的配置，甚至添加了setupTests.ts文件。
这是我的配置： package.json
{
....
"dependencies": {
"@babel/plugin-proposal-object-rest-spread": "^7.4.0",
"@babel/plugin-syntax-dynamic-import": "^7.2.0",
"@babel/polyfill": "^7.4.0",
"@babel/preset-env": "^7.4.2",
"@babel/preset-react": "^7.0.0",
"@babel/preset-typescript": "^7.3.3",
"@types/html-webpack-plugin": "^3.2.0",
"@types/jest": "^24.0.11",
"@types/react": "^16.8.10",
"@types/react-dom": "^16.8.3",
"@types/react-redux": "^7.0.6",
"@types/react-router-dom": "^4.3.1",
"@types/redux": "^3.6.0",
"@types/redux-logger": "^3.0.7",
"@types/redux-promise": "^0.5.28",
"@types/webpack": "^4.4.26",
"@typescript-eslint/eslint-plugin": "^1.5.0",
"@typescript-eslint/parser": "^1.5.0",
"babel-jest": "^24.5.0",
"babel-loader": "^8.0.5",
"babel-plugin-transform-class-properties": "^6.24.1",
"babel-preset-es2015": "^6.24.1",
"babel-preset-react": "^6.24.1",
"eslint": "^5.16.0",
"eslint-config-prettier": "^4.1.0",
"eslint-plugin-prettier": "^3.0.1",
"eslint-plugin-react-hooks": "^1.6.0",
"html-webpack-plugin": "^3.2.0",
"jest": "^24.5.0",
"jest-dom": "^3.1.3",
"prettier": "^1.16.4",
"react": "^16.8.6",
"react-dom": "^16.8.6",
"react-redux": "^6.0.1",
"react-router": "^5.0.0",
"react-router-dom": "^5.0.0",
"react-testing-library": "^6.0.3",
"redux": "^4.0.1",
"redux-logger": "^3.0.6",
"redux-promise": "^0.6.0",
"redux-thunk": "^2.3.0",
"styled-components": "^4.2.0",
"ts-loader": "^5.3.3",
"ts-node": "^8.0.3",
"webpack": "^4.29.6",
"webpack-dev-middleware": "^3.6.1",
"webpack-dev-server": "^3.2.1",
"webpack-hot-middleware": "^2.24.3"
},
"devDependencies": {
"@babel/core": "^7.4.0",
"awesome-typescript-loader": "^5.2.1",
"jest-environment-jsdom": "^24.5.0",
"source-map-loader": "^0.2.4",
"ts-jest": "^24.0.1",
"typescript": "^3.4.1",
"webpack-cli": "^3.3.0"
}
.babelrc
{
"presets": [
"@babel/react",
"@babel/typescript",
[
"@babel/preset-env",
{
"targets": {
"browsers": [">0.25%"]
},
"modules": false,
"useBuiltIns": "usage"
}
]
],
"plugins": ["@babel/proposal-class-properties", "@babel/proposal-object-rest-spread"]
}
jest.config.js
module.exports = {
roots: ['<rootDir>/src'],
transform: {
'.*.tsx?$': 'ts-jest',
},
testMatch: ['<rootDir>/src/**/?(*.)test.{ts,tsx}'],
moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node'],
setupFilesAfterEnv: [
'react-testing-library/cleanup-after-each', 'jest-dom/extend-expect']
};
webpack.config.js：
const path = require('path');
// Plugins
const path = require('path')
// Plugins
const HtmlWebpackPlugin = require('html-webpack-plugin')
module.exports = {
entry: {
dev: './src/index.tsx',
},
output: {
path: path.resolve(__dirname, 'dist'),
filename: 'js/[name].bundle.js',
},
devServer: {
compress: true,
port: 3000,
hot: true,
},
devtool: 'source-map',
resolve: {
extensions: ['.ts', '.tsx', '.js', '.jsx'],
},
module: {
rules: [
/**
* Gets all .ts, .tsx, or .js files and runs them through eslint
* and then transpiles them via babel.
*/
{
test: /(\.js$|\.tsx?$)/,
exclude: /(node_modules|bower_components)/,
use: ['babel-loader'],
},
/**
* All output '.js' files will have any sourcemaps re-processed by
* source-map-loader.
*/
{ test: /\.js$/, enforce: 'pre', loader: 'source-map-loader' },
],
},
plugins: [
new HtmlWebpackPlugin({
template: './public/index.html',
}),
],
}
非常基础的组件开始
import React, {SFC} from 'react'
export const Home: SFC<any> = () => <div>HomePage</div>
export default Home
当我什至尝试将组件作为参数传递给render方法时，都会出现错误
import { Home } from '../pages'; // this import works
import { render } from 'react-testing-library';
describe('', () => {
test('should render app', () => {
render(<Home />) // says it cant find "Home"
});
});
运行测试时，我会从控制台获得此信息：
● Test suite failed to run
TypeScript diagnostics (customize using `[jest-config].globals.ts-jest.diagnostics` option):
src/__tests__/App.test.ts:6:27 - error TS1005: '>' expected.
6 console.log(<Home />);
~
src/__tests__/App.test.ts:6:28 - error TS1161: Unterminated regular expression literal.
6 console.log(<Home />);
src/__tests__/App.test.ts:7:5 - error TS1005: ',' expected.
7 });
~
src/__tests__/App.test.ts:6:22 - error TS2749: 'Home' refers to a value, but is being used as a type here.
6 console.log(<Home />);
~~~~
更新：
当前我的文件名为App.test.ts
如果我将其更改为App.test.tsx
并将import * as React from 'react'添加到测试中
错误消失了，但是测试失败并显示以下错误：
● Test suite failed to run
Jest encountered an unexpected token
This usually means that you are trying to import a file which Jest cannot parse, e.g. it's not plain JavaScript.
By default, if Jest sees a Babel config, it will use that to transform your files, ignoring "node_modules".
Here's what you can do:
• To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
• If you need a custom transformation specify a "transform" option in your config.
• If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.
You'll find more details and examples of these config options in the docs:
https://jestjs.io/docs/en/configuration.html
Details:
/<user>/code/react-leader-board/src/__tests__/App.test.tsx:15
react_testing_library_1.render(<pages_1.Home />);
^
SyntaxError: Unexpected token <
at ScriptTransformer._transformAndBuildScript (node_modules/@jest/transform/build/ScriptTransformer.js:451:17)
at ScriptTransformer.transform (node_modules/@jest/transform/build/ScriptTransformer.js:493:19)
答案 0 :(得分：1)
我建议确保在环境预设的测试设置中编译您的模块：
{
"presets": [
"@babel/react",
"@babel/typescript",
[
"@babel/preset-env",
{
"targets": {
"browsers": [">0.25%"]
},
"modules": false,
"useBuiltIns": "usage"
}
]
],
"plugins": ["@babel/proposal-class-properties", "@babel/proposal-object-rest-spread"],
"env": {
"test": {
"presets": [
["@babel/preset-env", {
"modules": "commonjs"
}]
]
}
}
}
并使用babel-jest：
transform: { '\\.(ts|tsx)?$': 'babel-jest',`
答案 1 :(得分：1)
我遇到了同样的问题，问题是文件的扩展名，应该是.tsx，例如MyComponent.test.tsx