Angular Karma测试错误：＆＃34;未捕获的ReferenceError：未定义系统

Question

我收集了一些代码，我必须编写一些unint / e2e测试。我唯一的问题是我在运行ng测试时，收到此错误：

Chrome 67.0.3396 (Windows 10 0.0.0) ERROR
  {
    "message": "Uncaught ReferenceError: System is not defined\nat http://localhost:9876/_karma_webpack_/scripts.bundle.js:1:1\n\nReferenceError: System is not defined\n    at http://localhost:9876/_karma_webpack_/scripts.bundle.js:1:1",
    "str": "Uncaught ReferenceError: System is not defined\nat http://localhost:9876/_karma_webpack_/scripts.bundle.js:1:1\n\nReferenceError: System is not defined\n    at http://localhost:9876/_karma_webpack_/scripts.bundle.js:1:1"
  }

Chrome 67.0.3396 (Windows 10 0.0.0) ERROR
  {
    "message": "Uncaught ReferenceError: System is not defined\nat http://localhost:9876/_karma_webpack_/scripts.bundle.js:1:1\n\nReferenceError: System is not defined\n    at http://localhost:9876/_karma_webpack_/scripts.bundle.js:1:1",
    "str": "Uncaught ReferenceError: System is not defined\nat http://localhost:9876/_karma_webpack_/scripts.bundle.js:1:1\n\nReferenceError: System is not defined\n    at http://localhost:9876/_karma_webpack_/scripts.bundle.js:1:1"
  }

我觉得它与angular.json文件以及tsconf.spec文件有关。我尝试了很多可能的解决方案，我在网上找到但总是发现同样的错误。这是我的tsconf.spec和angular.josn。谢谢。

configspec：

{
  "extends": "../tsconfig.json",
  "compilerOptions": {
    "outDir": "../out-tsc/spec",
    "baseUrl": "./",
    "module": "commonjs",
    "types": [
      "jasmine",
      "node"
    ]
  },
  "files": [
    "test.ts"
  ],
  "include": [
    "**/*.spec.ts",
    "**/*.d.ts"
  ]
}

Angular.json

"$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "project": {
    "name": ""
  },
  "apps": [
    {
      "root": "src",
      "outDir": "dist",
      "assets": [
        "assets",
        "favicon.ico"
      ],
      "index": "index.html",
      "main": "main.ts",
      "polyfills": "polyfills.ts",
      "test": "test.ts",
      "tsconfig": "tsconfig.app.json",
      "testTsconfig": "tsconfig.spec.json",
      "prefix": "app",
      "styles": [
         "styles.css"
      ],
      "scripts": []


    }
  ],
  "e2e": {
    "protractor": {
      "config": "./protractor.conf.js"
    }
  },
  "lint": [
    {
      "project": "src/tsconfig.app.json",
      "exclude": "**/node_modules/**"
    },
    {
      "project": "src/tsconfig.spec.json",
      "exclude": "**/node_modules/**"
    },
    {
      "project": "e2e/tsconfig.e2e.json",
      "exclude": "**/node_modules/**"
    }
  ],
  "test": {
    "karma": {
      "config": "./karma.conf.js"
    }
  },
  "defaults": {
    "styleExt": "css",
    "component": {}
  }
}

我目前正在使用角度6，我已经回到4但仍然收到相同的错误。

编辑：解决了这个问题，但这是一个奇怪的解决方案。在我的angular.json文件中有一个导致此错误的脚本。我只是删除了脚本，一切都很好。