Problem running test: Cannot read property 'afterCompile'

Hi,
I'm a newbie working with unit test on Ionic and I'm having a rough time with this issue. I'm able to run the test without problem if I'm not using any spec files (I used #79 to get there), but I get the next error trying to test a page.

```
> karma start ./test-config/karma.conf.js

webpack: Compiled successfully.
webpack: Compiling...
01 03 2018 11:40:21.848:WARN [karma]: No captured browser, open http://localhost:9876/

webpack: Compiled with warnings.
01 03 2018 11:40:21.858:INFO [karma]: Karma v2.0.0 server started at http://0.0.0.0:9876/
01 03 2018 11:40:21.858:INFO [launcher]: Launching browser Chrome with unlimited concurrency
01 03 2018 11:40:21.915:INFO [launcher]: Starting browser Chrome
01 03 2018 11:40:30.401:INFO [Chrome 62.0.3202 (Linux 0.0.0)]: Connected on socket Vo5QLQDs_T0I_Q9pAAAA with id 48205151

START:
01 03 2018 11:40:31.055:WARN [reporter]: SourceMap position not found for trace: undefined
01 03 2018 11:40:31.056:WARN [reporter]: SourceMap position not found for trace: undefined
01 03 2018 11:40:31.057:WARN [reporter]: SourceMap position not found for trace: undefined
01 03 2018 11:40:31.057:WARN [reporter]: SourceMap position not found for trace: undefined
01 03 2018 11:40:31.057:WARN [reporter]: SourceMap position not found for trace: undefined
01 03 2018 11:40:31.058:WARN [reporter]: SourceMap position not found for trace: undefined
Chrome 62.0.3202 (Linux 0.0.0) ERROR
{
"message":
"Uncaught Error: Module build failed: TypeError: Cannot read property 'afterCompile'
of undefined\n at successfulTypeScriptInstance (/path/node_modules/ts-loader/dist/instances.js:147:27)\n
at Object.getTypeScriptInstance (/path/node_modules/ts-loader/dist/instances.js:48:12)\n
at Object.loader (/path/node_modules/ts-loader/dist/index.js:16:41)\nat karma-test-shim.js:80874:1\n\n
Error: Module build failed: TypeError: Cannot read property 'afterCompile' of undefined\n
at successfulTypeScriptInstance (/path/node_modules/ts-loader/dist/instances.js:147:27)\n
at Object.getTypeScriptInstance (/path/node_modules/ts-loader/dist/instances.js:48:12)\n
at Object.loader (/path/node_modules/ts-loader/dist/index.js:16:41)\n
at Object. (karma-test-shim.js:80874:7)\n at __webpack_require__ (webpack:///webpack/bootstrap%2034e18eb4bd6904d0fe6e:19:0 <- karma-test-shim.js:20:30)\n
at webpackContext (webpack:///src%20/.spec/.ts:5:0 <- karma-test-shim.js:80855:9)\n at Array.forEach ()\n at Object. (webpack:///test-config/karma-test-shim.js:16:0 <- karma-test-shim.js:73175:19)\n
at __webpack_require__ (webpack:///webpack/bootstrap%2034e18eb4bd6904d0fe6e:19:0 <- karma-test-shim.js:20:30)\n at webpack:///webpack/bootstrap%2034e18eb4bd6904d0fe6e:62:0 <- karma-test-shim.js:63:18\n at karma-test-shim.js:66:10",
"str": "Uncaught Error: Module build failed: TypeError: Cannot read property 'afterCompile'
of undefined\n at successfulTypeScriptInstance (/path/node_modules/ts-loader/dist/instances.js:147:27)\n
at Object.getTypeScriptInstance (/path/node_modules/ts-loader/dist/instances.js:48:12)\n
at Object.loader (/path/node_modules/ts-loader/dist/index.js:16:41)\nat karma-test-shim.js:80874:1\n\n
Error: Module build failed: TypeError: Cannot read property 'afterCompile' of undefined\n
at successfulTypeScriptInstance (/path/node_modules/ts-loader/dist/instances.js:147:27)\n
at Object.getTypeScriptInstance (/path/node_modules/ts-loader/dist/instances.js:48:12)\n
at Object.loader (/path/node_modules/ts-loader/dist/index.js:16:41)\n
at Object. (karma-test-shim.js:80874:7)\n at __webpack_require__ (webpack:///webpack/bootstrap%2034e18eb4bd6904d0fe6e:19:0 <- karma-test-shim.js:20:30)\n
at webpackContext (webpack:///src%20/.spec/.ts:5:0 <- karma-test-shim.js:80855:9)\n at Array.forEach ()\n at Object. (webpack:///test-config/karma-test-shim.js:16:0 <- karma-test-shim.js:73175:19)\n
at __webpack_require__ (webpack:///webpack/bootstrap%2034e18eb4bd6904d0fe6e:19:0 <- karma-test-shim.js:20:30)\n at webpack:///webpack/bootstrap%2034e18eb4bd6904d0fe6e:62:0 <- karma-test-shim.js:63:18\n at karma-test-shim.js:66:10"
}

Finished in 0.662 secs / 0 secs @ 11:40:31 GMT+0100 (CET)

SUMMARY:
✔ 0 tests completed
```
*webpack.test.js*
```
var webpack = require('webpack');
var path = require('path');

module.exports = {
devtool: 'inline-source-map',

resolve: {
extensions: ['.ts', '.js']
},

module: {
rules: [
{
test: /\.ts$/,
loaders: [
{
loader: 'ts-loader'
} , 'angular2-template-loader'
]
},
{
test: /\.html$/,
loader: 'html-loader?attrs=false'
},
{
test: /\.(png|jpe?g|gif|svg|woff|woff2|ttf|eot|ico)$/,
loader: 'null-loader'
}
]
},

plugins: [
new webpack.ContextReplacementPlugin(
/angular(\\|\/)core(\\|\/)@angular/,
root('./src'),
{}
),
new webpack.ContextReplacementPlugin(
/ionic-angular/,
root('./src'),
{}
),
]
};

function root(localPath) {
return path.resolve(__dirname, localPath);
}
```

*karma.conf.js*
```
var webpackConfig = require('./webpack.test.js');

module.exports = function(config) {
var _config = {
basePath: '',

frameworks: ['jasmine'],

files: [
{ pattern: './karma-test-shim.js', watched: true }
],

preprocessors: {
'./karma-test-shim.js': ['webpack', 'sourcemap']
},

webpack: webpackConfig,

webpackMiddleware: {
stats: 'errors-only'
},

webpackServer: {
noInfo: true
},

browserConsoleLogOptions: {
level: 'log',
format: '%b %T: %m',
terminal: true
},

reporters: ['mocha', 'kjhtml'],
port: 9876,
colors: true,
logLevel: config.LOG_INFO,
autoWatch: true,
browsers: ['Chrome'],
singleRun: false
};

config.set(_config);
};'

```
*karma-test-shim.js*
```
Error.stackTraceLimit = Infinity;

require('core-js/es6');
require('core-js/es7/reflect');
require('zone.js/dist/zone');
require('zone.js/dist/long-stack-trace-zone');
require('zone.js/dist/proxy');
require('zone.js/dist/sync-test');
require('zone.js/dist/jasmine-patch');
require('zone.js/dist/async-test');
require('zone.js/dist/fake-async-test');

var appContext = require.context('../src', true, /\.spec\.ts/);

appContext.keys().forEach(appContext);

var testing = require('@angular/core/testing');
var browser = require('@angular/platform-browser-dynamic/testing');

testing.TestBed.initTestEnvironment(
browser.BrowserDynamicTestingModule,
browser.platformBrowserDynamicTesting()
);
```

*spec file*
```
describe("Dashboard", () => {

it("Sum", () => expect(2+2).toBe(5));

})
```

*package.json*

```
"devDependencies": {
"@angular/tsc-wrapped": "^4.4.6",
"@ionic/app-scripts": "3.0.1",
"@types/jasmine": "^2.8.6",
"@types/jasminewd2": "^2.0.3",
"angular2-template-loader": "^0.6.2",
"html-loader": "^0.5.5",
"jasmine": "^2.99.0",
"karma": "^2.0.0",
"karma-chrome-launcher": "^2.2.0",
"karma-jasmine": "^1.1.1",
"karma-jasmine-html-reporter": "^0.2.2",
"karma-mocha-reporter": "^2.2.5",
"karma-sourcemap-loader": "^0.3.7",
"karma-webpack": "^2.0.13",
"null-loader": "^0.1.1",
"ts-loader": "^4.0.0",
"ts-node": "^5.0.0",
"typescript": "^2.4.2"
},
```
Any hint on what's happening?
Thanks for the help!