Reflect.getOwnMetadata不是因果类型脚本的函数

问题描述

我正在尝试进行单元测试(使用Karma +茉莉花+ karma-typescript )我的TypeScript项目.项目结构如下:

I am trying to unit test (with Karma + Jasmine + karma-typescript) my TypeScript project. The project structure is as follows:

root
|- src/*.ts              //all TypeScript source files
|- tests/unit/*.spec.ts  //all spec (test) files
|- karma.conf.js
|- tsconfig.json

我的karma.conf.js如下所示:

module.exports = function (config) {
  config.set({
    basePath: '',
    frameworks: ['jasmine', "karma-typescript"],
    karmaTypescriptConfig: {
      tsconfig: "./tsconfig.json"
    },
    files: [
      'src/*.ts',
      'tests/**/*Spec.ts'
    ],
    exclude: [],    
    preprocessors: {
      "**/*.ts": ["karma-typescript"]
    },
    reporters: ["progress", "karma-typescript"],
    port: 9876,
    colors: true,
    logLevel: config.LOG_INFO,
    autoWatch: true,
    browsers: ['Chrome'],
    singleRun: false,
    concurrency: Infinity
  })
}

我的规格文件如下所示:

My spec file looks like below:

import 'aurelia-polyfills'; //<- importing this, as the project have dependency on Aurelia
// import "babel-polyfill";
import "reflect-metadata";
import "jasmine";
import { Utility } from './../../src/Utility';

describe("this is a try to set up karma-jasmine-webpack test (TS)", () => {
    it("utility_test", () => {        
        const result = Utility.doSomething();
        const expected = Expected_Result;
        expect(result).toEqual(expected);
    });
});

但是当我运行karma start时，我会得到

But when I run karma start, I get

Chrome 55.0.2883 (Windows 10 0.0.0) ERROR
  Uncaught TypeError: Reflect.getOwnMetadata is not a function
  at C:/Users/spal/AppData/Local/Temp/karma-typescript-bundle-16376WqjdFvsYtjdI.js:2325

我认为这是因为pollyfill没有在浏览器中加载.但是，我在规格文件中已import ed aurelia-pollyfills.

I assume, that it is because of pollyfill(s) is/are not being loaded in the browser. However, I have imported aurelia-pollyfills in my spec file.

请提出如何更正此问题的建议.

Please suggest how this can be corrected.

更新:任何正在寻找答案的人，可能还会遇到karma-remap-istanbul中试图生成覆盖率报告的源地图(Error: Could not find source map for:'')的问题.

Update: Anyone looking at this for answer, might also face issues with source map (Error: Could not find source map for:'') from karma-remap-istanbul trying to generate coverage report.

避免此问题的一种方法是简单地删除有问题的报告程序插件.例如，将reporters: ['mocha', 'coverage', 'karma-remap-istanbul']更改为reporters: ['mocha', 'coverage'].

One way to avoid this problem is to simply remove the problematic reporter plugin. For example, change reporters: ['mocha', 'coverage', 'karma-remap-istanbul'] to reporters: ['mocha', 'coverage'].

其他解决方案是生成源地图.如果无法在tsconfig.json中指定相同的名称，则可以在karma.conf.js中指定(如果使用的是karma-typescript):

Other solution would be to generate the source maps. In case you can't specify the same in your tsconfig.json, you can specify that in karma.conf.js if you are using karma-typescript:

karmaTypescriptConfig: {
  tsconfig: "./tsconfig.json",
  compilerOptions: {
    sourceMap: true
  }
}

最后，我以reporters: ["mocha", "karma-typescript"]结尾，它显示了哪个测试通过，哪个测试失败以及生成覆盖率报告.

Lastly, I ended up with reporters: ["mocha", "karma-typescript"], as it shows which test passed, and which failed, as well as generate a coverage report.

推荐答案

您可能缺少reflect-metadata导入:

然后将以下内容添加到您的files:

Then add the following to your files:

files: [
    { pattern: "node_modules/reflect-metadata/Reflect.js", include: true },
    { pattern: "src/*.ts", include: true },
    { pattern: "tests/**/*Spec.ts", include: true }
]

这篇关于Reflect.getOwnMetadata不是因果类型脚本的函数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！