Karma Coverage not finding files (angular2 / typescript)

I am working on getting an app set up using Angular 2 w/ typescript and I'm having issues getting my karma coverage to find the files I want it to inspect. I've set this up successfully on an angular 1.x application but there seems to be another layer I'm missing with typescript.

Everything runs just fine, I see all of my unit tests being checked by karma as expected and coverage says everything was okay and that my code has 100% coverage, which threw up a red flag. After checking the html output for coverage I saw that I have 100% coverage because no files are being checked.

Looking at the output in my terminal I see that all of the files I have selected with patte: './src/**/*.js' are being excluded, which means it is only finding the .ts files and not compiling them into js. I had added the typescriptPreprocesser thinking that it would convert the ts files into js files during testing so that the coverage tool could parse them, but nothing I've done so far is working.

Here's my karam.conf.js file in it's entirety:

var path = require('path');

var webpackConfig = require('./webpack.config');

module.exports = function (config) {
  var _config = {

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

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

    // list of files / pattes to load in the browser
    files: [
      {
        patte: './karma-shim.js',
        watched: false
      },
      {
        patte: './src/**/*.js',
        included: true
      }
    ],

    // list of files to exclude
    exclude: [
      './src/e2e/*'
    ],

    // preprocess matching files before serving them to the browser
    // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
    preprocessors: {
      './karma-shim.js': ['webpack', 'sourcemap'],
      './src/**/*.ts': ['typescript'],
      './src/**/*.js': ['coverage']
    },

    typescriptPreprocessor: {
      // options passed to the typescript compiler
      options: {
        sourceMap: false, // (optional) Generates corresponding .map file.
        target: 'ES5', // (optional) Specify ECMAScript target version: 'ES3' (default), or 'ES5'
        module: 'amd', // (optional) Specify module code generation: 'commonjs' or 'amd'
        noImplicitAny: true, // (optional) Wa on expressions and declarations with an implied 'any' type.
        noResolve: true, // (optional) Skip resolution and preprocessing.
        removeComments: true, // (optional) Do not emit Idea to output.
        concatenateOutput: false // (optional) Concatenate and emit output to single file. By default true if module option is omited, otherwise false.
      },
      // transforming the filenames
      transformPath: function(path) {
        retu path.replace(/.ts$/, '.js');
      }
    },

    webpack: webpackConfig,

    webpackMiddleware: {
      // webpack-dev-middleware configuration
      // i. e.
      stats: 'errors-only'
    },

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

    remapIstanbulReporter: {
      src: 'coverage/json/coverage-final.json',
      reports: {
        lcovonly: 'coverage/json/lcov.info',
        html: 'coverage/html',
        'text': null
      },
      timeoutNotCreated: 1000, // default value
      timeoutNoMoreFiles: 1000 // default value
    },

    webpackServer: {
      noInfo: true // please don't spam the console when ruing in karma!
    },

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

    // 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: false,

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

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

  config.set(_config);

};

Any thoughts on what I'm doing wrong here?