Added testing utils functions

src/app/shared/testing/utils.ts

@@ -0,0 +1,32 @@
+import { ComponentFixture, TestBed } from '@angular/core/testing';
+
+/**
+ * Returns true if a Native Element has a specified css class.
+ *
+ * @param element
+ *    the Native Element
+ * @param className
+ *    the class name to find
+ */
+export const hasClass = (element: any, className: string): boolean => {
+  const classes = element.getAttribute('class');
+  return classes.split(' ').indexOf(className) !== -1;
+};
+
+/**
+ * Creates an instance of a component and returns test fixture.
+ *
+ * @param html
+ *    the component's template as html
+ * @param type
+ *    the type of the component to instantiate
+ */
+export const createTestComponent = <T>(html: string, type: { new(...args: any[]): T }): ComponentFixture<T> => {
+  TestBed.overrideComponent(type, {
+    set: {template: html}
+  });
+  const fixture = TestBed.createComponent(type);
+
+  fixture.detectChanges();
+  return fixture as ComponentFixture<T>;
+};