karma.conf.js

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

    frameworks: ["mocha", "karma-typescript"],

    files: [
      { pattern: 'node_modules/babel-polyfill/browser.js' },
      { pattern: "src/**/*.ts" },
      { pattern: "test/**/*.spec.ts" }
    ],

    exclude: [
      "/**/*.d.ts"
    ],

    preprocessors: {
      "**/*.ts": ["karma-typescript"]
    },

    client: {
      mocha: {
        // Use this as needed during developer to filter tests.
        grep: ''
      }
    },

    // https://github.com/monounity/karma-typescript
    karmaTypescriptConfig: {
      reports: {
        "text": null,
        "text-summary": null,
        "html": "coverage",
      },
      compilerOptions: {
        target: "es5",
        lib: [
          "es2017",
          "dom"
        ]
      }
    },

    reporters: ["karma-typescript", "mocha"],

    browsers: ["PhantomJS"]
  });
};