单元测试Javascript – 对象不是构造函数

我正在尝试学习测试一些javascript文件.使用mocha和chai与webpack.

这是我的test / karma.conf.js

var webpack = require('webpack');

module.exports = function (config) {
  config.set({
    browsers: [ 'PhantomJS' ],
    singleRun: true,
    frameworks: [ 'mocha' ],
    files: [
      'tests.webpack.js'
    ],
    preprocessors: {
      'tests.webpack.js': [ 'webpack', 'sourcemap' ]
    },
    reporters: [ 'spec' ],
    webpack: {
      devtool: 'inline-source-map',
      module: {
        loaders: [
          { test: /\.js$/, loader: 'babel-loader' }
        ]
      }
    },
    webpackServer: {
      noInfo: true
    }
  });
};

这是我在karma配置上使用的test / test.webpack.js：

import chai from 'chai'

global.chai = chai
global.expect = chai.expect
global.should = chai.should()

var context = require.context('../src', true, /spec\.js$/);
context.keys().forEach(context);

我的测试非常基础,只是为了测试它是否正常工作src / index.spec.js：

describe("A test suite", function() {
   beforeEach(function() { });
   afterEach(function() { });
   it('should fail', function() { expect(true).to.be.true; });
});

当我尝试运行测试时,我收到了这个错误

./node_modules/karma/bin/karma start test / karma.conf.js

01 04 2016 14:15:08.191:INFO [karma]: Karma v0.13.22 server started at http://localhost:9876/
01 04 2016 14:15:08.255:INFO [launcher]: Starting browser PhantomJS
01 04 2016 14:15:12.443:INFO [PhantomJS 2.1.1 (Windows 8 0.0.0)]: Connected on socket /#GivXNjnm0g5H9DBXAAAA with id 29314805

PhantomJS 2.1.1 (Windows 8 0.0.0) ERROR
  TypeError: Object is not a constructor (evaluating '$export($export.S + $export.F * !__webpack_require__(17), 'Object', { defineProperty: __webpack_require__(13).f })')
  at C:/Users/pablo.feldman/Documents/Projects/jpmc-components/test/tests.webpack.js:535 <- webpack:///~/babel-runtime/~/core-js/library/modules/es6.object.define-property.js:3:0

PhantomJS 2.1.1 (Windows 8 0.0.0): Executed 0 of 0 ERROR (0.101 secs / 0 secs)

解决方法:

我有完全相同的问题,谷歌搜索解决方案时遇到了这个帖子.不幸的是没有解决方案,所以花了几个小时尝试不同的建议后我找到了正确的配置.

这是我做的：

>已安装的phantomjs-polyfill-object-assign模块

    npm install --save-dev phantomjs-polyfill-object-assign

>在karma的files属性下配置上面的polyfill：

    ...
    files: [
        '../node_modules/phantomjs-polyfill-object-assign/object-assign-polyfill.js',
        'test/variables.js',
        'test/**/*.spec.js',
    ],
    ...

注意：根据您的业力配置,上述填充路径可能需要调整.

>使用exclude属性更新了babel-loader配置：

    ...
    loaders: [{
        test: /\.js$/,
        loader: 'babel-loader',
        exclude: /node_modules/,
    },
    ...

就是这样,测试可以再次运行.

标签：chai,javascript,unit-testing,mocha,karma-runner
来源： https://codeday.me/bug/20190829/1759176.html