karma.conf.js

module.exports = function (config) {
	var karmaConfig = {
    frameworks: ["mocha", "chai", "sinon", "karma-typescript"],
    mime: {
      'text/x-typescript': ['ts','tsx']
    },
    client: {
      mocha: {
        opts: "./mocha.opts",
      },
    },
    files: [
      "./node_modules/hammer-simulator/index.js",
      "./test/setup.js",
      "./test/hammer-simulator.run.js",
      "./src/**/*.ts",
      "./test/unit/*.ts"
    ],
    preprocessors: {
      "src/**/*.ts": ["karma-typescript"],
      "test/unit/*.ts": ["karma-typescript"],
    },
    karmaTypescriptConfig: {
      tsconfig: "./tsconfig.test.json",
      reports: {
        html: {
          "directory": "coverage",
          "subdirectory": "./"
        },
        lcovonly: {
          "directory": "coverage",
          "filename": "lcov.info",
          "subdirectory": "."
        },
      },
      coverageOptions: {
        instrumentation: true,
        exclude: /test/i,
      }
    },
    browsers: [],
    customLaunchers: {
      CustomChromeHeadless: {
        base: "ChromeHeadless",
        flags: ["--window-size=400,300", "--no-sandbox", "--disable-setuid-sandbox"],
      },
    },
    reporters: ["mocha"],
	};

	karmaConfig.browsers.push(config.chrome ? "Chrome" : "CustomChromeHeadless");

	if (config.coverage) {
		karmaConfig.reporters.push("karma-typescript");
		karmaConfig.singleRun = true;
	}

	config.set(karmaConfig);
};