运行 Jest 测试时出现意外标记 'import' 错误?
Unexpected token 'import' error while running Jest tests?
我知道这个问题已被问过好几次,但我遇到的所有解决方案似乎都不适合我。我在尝试 运行 对 Vue 应用程序进行 Jest 测试时 运行 遇到了以下错误。
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://facebook.github.io/jest/docs/en/configuration.html
Details:
/node_modules/vue-awesome/icons/expand.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import Icon from '../components/Icon.vue'
^^^^^^
SyntaxError: Unexpected token import
> 17 | import 'vue-awesome/icons/expand'
.babelrc:
{
"presets": [
["env", {
"modules": false,
"targets": {
"browsers": ["> 1%", "last 2 versions", "not ie <= 8"]
}
}]
],
"env": {
"test": {
"presets": [
["env", { "targets": { "node": "current" }}]
]
}
}
}
package.json 中的开玩笑配置:
"jest": {
"moduleFileExtensions": [
"js",
"vue"
],
"moduleNameMapper": {
"^@/(.*)$": "<rootDir>/src/"
},
"transform": {
"^.+\.js$": "<rootDir>/node_modules/babel-jest",
".*\.(vue)$": "<rootDir>/node_modules/vue-jest"
},
"snapshotSerializers": [
"<rootDir>/node_modules/jest-serializer-vue"
],
"moduleDirectories": [
"node_modules",
"src"
]
}
看起来为测试安装的 Vue 组件在脚本中的初始导入工作正常,但无法识别模块本身 (import Icon from '../components/Icon.vue
) 中的导入。
样板回购重现问题:github.com/DonaldPeat/Whosebug-jest-question
我该如何解决这个问题?
你只需要确保vue-awesome
会被jest转化,所以添加
以下是你的笑话配置:
transformIgnorePatterns: ["/node_modules/(?!vue-awesome)"],
意思是:“忽略 node_modules 中的所有内容,除了 vue-awesome
。
这里还有可能导致此错误的其他问题的详尽列表:https://github.com/facebook/jest/issues/2081
如果您在更新到较新的 Jest 版本后遇到此问题,请尝试清除 Jest 的内部缓存:
jest --clearCache
我们在另一个图书馆遇到了同样的问题。根本原因是我们在代码中存在循环依赖。但是错误文本根本没有提到它。就像在这个 post: "Jest encountered an unexpected token..."
在我的例子中,我需要 jest.config.js
文件中的 testEnvironment: "node"
。当我开始针对 Vue Router 进行测试时出现错误。
// jest.config.js
module.exports = {
preset: "@vue/cli-plugin-unit-jest/presets/typescript",
transform: {
"^.+\.vue$": "vue-jest",
".+\.(css|styl|less|sass|scss|png|jpg|ttf|woff|woff2)$":
"jest-transform-stub",
},
moduleNameMapper: {
"^.+.(css|styl|less|sass|scss|png|jpg|ttf|woff|woff2)$":
"jest-transform-stub",
},
testEnvironment: "node", // It fixes my issue
};
在 package.json
中添加这个对我有用(将 <package_name>
替换为导致包名称)
"jest": {
"transformIgnorePatterns": ["node_modules/(?!<package_name>)/"]
}
我知道这个问题已被问过好几次,但我遇到的所有解决方案似乎都不适合我。我在尝试 运行 对 Vue 应用程序进行 Jest 测试时 运行 遇到了以下错误。
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://facebook.github.io/jest/docs/en/configuration.html
Details:
/node_modules/vue-awesome/icons/expand.js:1
({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,global,jest){import Icon from '../components/Icon.vue'
^^^^^^
SyntaxError: Unexpected token import
> 17 | import 'vue-awesome/icons/expand'
.babelrc:
{
"presets": [
["env", {
"modules": false,
"targets": {
"browsers": ["> 1%", "last 2 versions", "not ie <= 8"]
}
}]
],
"env": {
"test": {
"presets": [
["env", { "targets": { "node": "current" }}]
]
}
}
}
package.json 中的开玩笑配置:
"jest": {
"moduleFileExtensions": [
"js",
"vue"
],
"moduleNameMapper": {
"^@/(.*)$": "<rootDir>/src/"
},
"transform": {
"^.+\.js$": "<rootDir>/node_modules/babel-jest",
".*\.(vue)$": "<rootDir>/node_modules/vue-jest"
},
"snapshotSerializers": [
"<rootDir>/node_modules/jest-serializer-vue"
],
"moduleDirectories": [
"node_modules",
"src"
]
}
看起来为测试安装的 Vue 组件在脚本中的初始导入工作正常,但无法识别模块本身 (import Icon from '../components/Icon.vue
) 中的导入。
样板回购重现问题:github.com/DonaldPeat/Whosebug-jest-question
我该如何解决这个问题?
你只需要确保vue-awesome
会被jest转化,所以添加
以下是你的笑话配置:
transformIgnorePatterns: ["/node_modules/(?!vue-awesome)"],
意思是:“忽略 node_modules 中的所有内容,除了 vue-awesome
。
这里还有可能导致此错误的其他问题的详尽列表:https://github.com/facebook/jest/issues/2081
如果您在更新到较新的 Jest 版本后遇到此问题,请尝试清除 Jest 的内部缓存:
jest --clearCache
我们在另一个图书馆遇到了同样的问题。根本原因是我们在代码中存在循环依赖。但是错误文本根本没有提到它。就像在这个 post: "Jest encountered an unexpected token..."
在我的例子中,我需要 jest.config.js
文件中的 testEnvironment: "node"
。当我开始针对 Vue Router 进行测试时出现错误。
// jest.config.js
module.exports = {
preset: "@vue/cli-plugin-unit-jest/presets/typescript",
transform: {
"^.+\.vue$": "vue-jest",
".+\.(css|styl|less|sass|scss|png|jpg|ttf|woff|woff2)$":
"jest-transform-stub",
},
moduleNameMapper: {
"^.+.(css|styl|less|sass|scss|png|jpg|ttf|woff|woff2)$":
"jest-transform-stub",
},
testEnvironment: "node", // It fixes my issue
};
在 package.json
中添加这个对我有用(将 <package_name>
替换为导致包名称)
"jest": {
"transformIgnorePatterns": ["node_modules/(?!<package_name>)/"]
}