打字稿，Babel 7，业力，茉莉花，代码覆盖率配置

Question

我正在用Typescript开发一个独立的库，并尝试使用Karma，Jasmine和Babel 7设置单元测试和代码覆盖率。我编写了几个简单的测试，并试图让Karma运行它们，但零测试正在跑步。消息03 08 2019 07:36:35.252:WARN [middleware:karma]: Invalid file type (ts), defaulting to js.被发送到控制台，随后是Executed 0 of 0 ERROR (0.005 secs / 0 secs)。这告诉我我从Karma配置文件中丢失了一些内容，但是我不确定丢失的部分是什么。

karma.config.js

module.exports = function (config) {
    config.set({

        // base path that will be used to resolve all patterns (eg. files, exclude)
        basePath: '',


        // frameworks to use
        // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
        frameworks: ['jasmine'],


        // list of files / patterns to load in the browser
        files: [
            'src/**/*.ts'
        ],


        // list of files / patterns to exclude
        exclude: [],

        // preprocess matching files before serving them to the browser
        // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
        preprocessors: {
            'spec/**/*.spec.ts': ['babel'],
            'src/**/*.ts': ['babel']
        },


        // test results reporter to use
        // possible values: 'dots', 'progress'
        // available reporters: https://npmjs.org/browse/keyword/karma-reporter
        reporters: ['progress'],

        coverageReporter: {
            reporters: [
                {
                    type: 'html',
                    dir: 'coverage/'
                }
            ]
        },

        // web server port
        port: 9876,


        // enable / disable colors in the output (reporters and logs)
        colors: true,


        // level of logging
        // possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
        logLevel: config.LOG_INFO,


        // enable / disable watching file and executing tests whenever any file changes
        autoWatch: true,


        // start these browsers
        // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
        browsers: ['Chrome'],


        // Continuous Integration mode
        // if true, Karma captures browsers, runs the tests and exits
        singleRun: false,

        // Concurrency level
        // how many browser should be started simultaneous
        concurrency: Infinity,
    });
};

.babelrc

{
    "sourceMaps": "inline",
    "presets": [
        "@babel/env",
        "@babel/typescript"
    ],
    "plugins": [
        "@babel/proposal-class-properties",
        "@babel/proposal-object-rest-spread"
    ]
}