运行Mocha测试时Babel意外导入令牌 [英] Babel unexpected token import when running mocha tests

问题描述

其他相关问题中提供的解决方案，例如在.babelrc中包含正确的预设(es2015)，已在我的项目中实现.

The solutions offered in other related questions, such as including the proper presets (es2015) in .babelrc, are already implemented in my project.

我有两个项目(分别称为A和B)，它们都使用ES6模块语法.在项目A中，我导入了通过npm安装的项目B，该项目位于node_modules文件夹中.当我运行项目A的测试套件时，出现错误:

I have two projects (lets call them A and B) which both use ES6 module syntax. In Project A, I'm importing Project B which is installed via npm and lives in the node_modules folder. When I run my test suite for Project A, I'm getting the error:

SyntaxError:意外的令牌导入

SyntaxError: Unexpected token import

在此之前，项目B的这行所谓的错误代码行:

Which is preceded by this alleged erroneous line of code from Project B:

(函数(导出，需求，模块，__文件名，__目录名){导入 来自'history/lib/createBrowserHistory'的createBrowserHistory;

(function (exports, require, module, __filename, __dirname) { import createBrowserHistory from 'history/lib/createBrowserHistory';

由于我的源文件仅包含从'history/lib/createBrowserHistory'导入import createBrowserHistory"，因此iife似乎与npm或babel有关，因为Project B的测试套件中的单元测试运行良好，并且如果我将Project B删除为来自Project A的依赖项，然后我的测试套件(仍然对内部项目模块使用es6导入)就可以正常工作.

The iife appears to be something npm or possibly babel related since my source file only contains "import createBrowserHistory from 'history/lib/createBrowserHistory'; The unit tests in Project B's test suite runs fine, and if I remove Project B as a dependency from Project A, my test suite then (still using es6 imports for internal project modules) works just fine.

完整堆栈跟踪:

 SyntaxError: Unexpected token import
    at exports.runInThisContext (vm.js:53:16)
    at Module._compile (module.js:374:25)
    at Module._extensions..js (module.js:405:10)
    at Object.require.extensions.(anonymous function) [as .js] (/ProjectA/node_modules/babel-register/lib/node.js:138:7)
    at Module.load (module.js:344:32)
    at Function.Module._load (module.js:301:12)
    at Module.require (module.js:354:17)
    at require (internal/module.js:12:17)
    at Object.<anonymous> (actionCreators.js:4:17)
    at Module._compile (module.js:398:26)
    at loader (/ProjectA/node_modules/babel-register/lib/node.js:130:5)
    at Object.require.extensions.(anonymous function) [as .js] (/ProjectA/node_modules/babel-register/lib/node.js:140:7)
    at Module.load (module.js:344:32)
    at Function.Module._load (module.js:301:12)
    at Module.require (module.js:354:17)
    at require (internal/module.js:12:17)
    at Object.<anonymous> (/ProjectA/src/components/core/wrapper/wrapper.js:28:23)
    at Module._compile (module.js:398:26)
    at loader (/ProjectA/node_modules/babel-register/lib/node.js:130:5)
    at Object.require.extensions.(anonymous function) [as .js] (/ProjectA/node_modules/babel-register/lib/node.js:140:7)
    at Module.load (module.js:344:32)
    at Function.Module._load (module.js:301:12)
    at Module.require (module.js:354:17)
    at require (internal/module.js:12:17)
    at Object.<anonymous> (/ProjectA/src/components/core/wrapper/wrapperSpec.js:15:16)
    at Module._compile (module.js:398:26)
    at loader (/ProjectA/node_modules/babel-register/lib/node.js:130:5)
    at Object.require.extensions.(anonymous function) [as .js] (/ProjectA/node_modules/babel-register/lib/node.js:140:7)
    at Module.load (module.js:344:32)
    at Function.Module._load (module.js:301:12)
    at Module.require (module.js:354:17)
    at require (internal/module.js:12:17)
    at /ProjectA/node_modules/mocha/lib/mocha.js:219:27
    at Array.forEach (native)
    at Mocha.loadFiles (/ProjectA/node_modules/mocha/lib/mocha.js:216:14)
    at Mocha.run (/ProjectA/node_modules/mocha/lib/mocha.js:468:10)
    at Object.<anonymous> (/ProjectA/node_modules/mocha/bin/_mocha:403:18)
    at Module._compile (module.js:398:26)
    at Object.Module._extensions..js (module.js:405:10)
    at Module.load (module.js:344:32)
    at Function.Module._load (module.js:301:12)
    at Function.Module.runMain (module.js:430:10)
    at startup (node.js:141:18)
    at node.js:980:3

这是我来自package.json的测试命令:

Here is my test command from package.json:

"test": "mocha --compilers js:babel-core/register '+(test|src)/**/*Spec.js'"

此StackOverflow帖子类似，但没有为我使用命令行提供解决方案: 从带有babel的node_modules中导入模块但失败了

This StackOverflow post is similar but doesn't offer a solution for my use of the command line: import a module from node_modules with babel but failed

推荐答案

似乎唯一的解决方案是显式包括:

It seems the only solution is to explicitly include:

require('babel-core/register')({
  ignore: /node_modules/(?!ProjectB)/
}); 

放在测试帮助文件中，然后在我的测试命令中将其传递给mocha:

in a test helper file, and pass that along to mocha in my test command:

mocha --require ./test/testHelper.js...

---

最终解决方案:

添加 registerBabel.js :一个单独的文件，其工作是需要babel-core/register ...

Add registerBabel.js: a separate file whose job is to require babel-core/register...

require('babel-core/register')({
  ignore: /node_modules/(?!ProjectB)/
});

如果您的应用程序还依赖于babel-node，请添加 entry.js .这可以作为包含es6的应用程序的包装.

Add an entry.js if your application also relies on babel-node. This acts as a wrapper for your es6 containing application.

require('./registerBabel');
require('./server'); // this file has some es6 imports

然后您将使用node entry

对于Mocha测试， testHelper.js 也应要求registerBabel.js在运行时初始化babel支持.

For mocha testing, testHelper.js should require registerBabel.js as well to initialize babel support at run time.

require('./registerBabel');

并使用mocha --require ./testHelper.js '+(test)/**/*Spec.js'

这将递归地测试"./test"中任何以"Spec.js"结尾的文件.用一种与您的项目中的规范匹配的模式替换该模式.

This will recursively test any file ending in "Spec.js" within "./test". Substitute the pattern with one matching the specs in your project.

这篇关于运行Mocha测试时Babel意外导入令牌的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！