added snapshot and component tests

package.json

@@ -63,6 +63,24 @@
     ]
   },
   "devDependencies": {
-    "@types/react-router-dom": "^5.1.9"
+    "@types/enzyme": "^3.10.9",
+    "@types/enzyme-adapter-react-16": "^1.0.6",
+    "@types/react-router-dom": "^5.1.9",
+    "enzyme": "^3.11.0",
+    "enzyme-adapter-react-16": "^1.15.6",
+    "enzyme-to-json": "^3.6.2",
+    "react-test-renderer": "^17.0.2"
+  },
+  "jest": {
+    "snapshotSerializers": [
+      "enzyme-to-json/serializer"
+    ],
+    "collectCoverageFrom": [
+      "src/**/*.js",
+      "!src/index.js"
+    ],
+    "coverageReporters": [
+      "text"
+    ]
   }
 }

src/App.tsx

 
 import {Redirect, Route, Switch} from 'react-router';
 import LandingPage from "./pages/landingPage/landingPage";
-import OverviewPage from "./pages/overviewPage/overview";
 import { GlobalCommitContext } from './context/commitPageContext';
 import { useState } from 'react';
 import IssuePage from './pages/issueListPage/issuePage';
 import { CommitPage } from './pages/commitGraphPage/CommitPage';
 import { IssueGraphPage } from './pages/issueGraphPage/issueGraphPage';
 import CommitPageWrapper from "./pages/commitListPage/commitPageWrapper"
-import GobackButton from './components/goBack/goBackButton';
+import OverviewPage from './pages/overviewPage/Overview';
 
 function App() {
     const [testContext, setTestContext] = useState<string>('Admin');   

src/test/__snapshots__/snapshot.test.tsx.snap

+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`renders the App Component 1`] = `
+<div
+  className="App"
+>
+  <Switch>
+    <Route
+      exact={true}
+      path="/"
+    >
+      <LandingPage />
+    </Route>
+    <Route
+      exact={true}
+      path="/overview"
+    >
+      <OverviewPage />
+    </Route>
+    <Route
+      exact={true}
+      path="/issue"
+    >
+      <OverviewPage />
+    </Route>
+    <Route
+      exact={true}
+      path="/commit"
+    >
+      <OverviewPage />
+    </Route>
+    <Route
+      exact={true}
+      path="/issuelist"
+    >
+      <IssuePage />
+    </Route>
+    <Route
+      exact={true}
+      path="/issuegraph"
+    >
+      <IssueGraphPage />
+    </Route>
+    <Route
+      exact={true}
+      path="/commitlist"
+    >
+      <CommitPageWrapper />
+    </Route>
+    <Route
+      exact={true}
+      path="/commitgraph"
+    >
+      <ContextProvider
+        value={
+          Object {
+            "setTestContext": [Function],
+            "testContext": "Admin",
+          }
+        }
+      >
+        <CommitPage />
+      </ContextProvider>
+    </Route>
+    <Redirect
+      to="/"
+    />
+  </Switch>
+</div>
+`;
+
+exports[`renders the CommitGraphPage 1`] = `
+<div
+  className="pageContainer"
+>
+  <GobackButton />
+  <h1>
+    Charts for issues
+  </h1>
+  <BarChart
+    title="Commits per day"
+  />
+  <PieChart
+    title="Commits per member"
+  />
+</div>
+`;
+
+exports[`renders the CommitListPage 1`] = `
+<div>
+  <GobackButton />
+  <h1>
+    Commits
+  </h1>
+  <div
+    className="ArrowDiv"
+  >
+    <button
+      className="Button"
+      disabled={true}
+      onClick={[Function]}
+    >
+      <i
+        className="Arrow Left"
+      />
+    </button>
+    <h4>
+      1
+    </h4>
+    <button
+      className="Button"
+      disabled={false}
+      onClick={[Function]}
+    >
+      <i
+        className="Arrow Right"
+      />
+    </button>
+  </div>
+  <CommitComponent />
+</div>
+`;
+
+exports[`renders the IssueGraphPage 1`] = `
+<div
+  className="pageContainer"
+>
+  <GobackButton />
+  <h1>
+    Charts for issues
+  </h1>
+  <BarChart
+    title="Issues authored per day"
+  />
+  <PieChart
+    title="Issues authored per member"
+  />
+</div>
+`;
+
+exports[`renders the IssueListpage 1`] = `
+<div
+  className="container"
+>
+  <GobackButton />
+  <h1
+    className="headline"
+  >
+     Issues 
+  </h1>
+  <IssuesListComponent />
+</div>
+`;
+
+exports[`renders the LandingPage 1`] = `
+<div
+  className="inputWrapper"
+>
+  <img
+    alt="visualization"
+    src="gitlab.jpeg"
+    style={
+      Object {
+        "margin": "30px auto",
+        "width": "80%",
+      }
+    }
+  />
+  <button
+    className="defaultButton"
+    onClick={[Function]}
+  >
+    set default values
+  </button>
+  <form
+    onSubmit={[Function]}
+  >
+    <input
+      className="inputField"
+      id="ProjektIDInput"
+      onChange={[Function]}
+      placeholder="ProjectId"
+      required={true}
+      type="Text"
+      value=""
+    />
+    <input
+      className="inputField"
+      id="KeyInput"
+      onChange={[Function]}
+      placeholder="Key"
+      required={true}
+      type="Text"
+      value=""
+    />
+    <button
+      className="submitButton"
+      disabled={true}
+      type="submit"
+    >
+      Use values
+    </button>
+    <ToastContainer
+      autoClose={3000}
+      closeButton={[Function]}
+      closeOnClick={true}
+      draggable={true}
+      draggableDirection="x"
+      draggablePercent={80}
+      hideProgressBar={false}
+      newestOnTop={false}
+      pauseOnFocusLoss={true}
+      pauseOnHover={true}
+      position="top-right"
+      role="alert"
+      rtl={false}
+      theme="light"
+      transition={[Function]}
+    />
+  </form>
+</div>
+`;
+
+exports[`renders the overviewPage 1`] = `
+<div
+  className="wrapper"
+>
+  <GobackButton />
+  <h2
+    style={
+      Object {
+        "marginTop": "30px",
+      }
+    }
+  >
+    Choose display form:
+  </h2>
+  <div
+    className="buttonWrapper"
+  >
+    <button
+      className="button"
+      onClick={[Function]}
+    >
+      Graph
+    </button>
+    <button
+      className="button"
+      onClick={[Function]}
+    >
+      List
+    </button>
+  </div>
+</div>
+`;

src/test/component.test.tsx

+import { shallow } from "enzyme";
+import GobackButton from "../components/goBack/goBackButton";
+import Enzyme from 'enzyme';
+import ReactSixteenAdapter from 'enzyme-adapter-react-16';
+import OverviewPage from "../pages/overviewPage/Overview";
+
+Enzyme.configure({ adapter: new ReactSixteenAdapter() });
+
+const wrapped = shallow(<OverviewPage/>);
+describe('OverviewPage', () => {
+  it('should render the OverviewPage', () => {   
+    expect(wrapped.find(".buttonWrapper").children().length).toEqual(2);
+    expect(wrapped.find(".buttonWrapper").childAt(0).text()).toEqual("Graph");
+    expect(wrapped.find(".buttonWrapper").childAt(1).text()).toEqual("List");
+    expect(wrapped.find("h2").text()).toEqual("Choose display form:");
+  });
+});
\ No newline at end of file

src/test/snapshot.test.tsx

+import { shallow } from 'enzyme';
+import App from '../App';
+import Enzyme from 'enzyme';
+import ReactSixteenAdapter from 'enzyme-adapter-react-16';
+import IssuePage from '../pages/issueListPage/issuePage';
+import { IssueGraphPage } from '../pages/issueGraphPage/issueGraphPage';
+import OverviewPage from '../pages/overviewPage/Overview';
+import LandingPage from '../pages/landingPage/landingPage';
+import CommitPageWrapper from '../pages/commitListPage/commitPageWrapper';
+import { CommitPage } from '../pages/commitGraphPage/CommitPage';
+
+Enzyme.configure({ adapter: new ReactSixteenAdapter() });
+
+test('renders the App Component', () => {
+    const component = shallow(<App/>);
+    expect(component).toMatchSnapshot();
+  });
+test('renders the IssueListpage', () => {
+    const component = shallow(<IssuePage/>);
+    expect(component).toMatchSnapshot();
+  });
+test('renders the IssueGraphPage', () => {
+    const component = shallow(<IssueGraphPage/>);
+    expect(component).toMatchSnapshot();
+  });
+test('renders the overviewPage', () => {
+    const component = shallow(<OverviewPage/>);
+    expect(component).toMatchSnapshot();
+  });
+test('renders the LandingPage', () => {
+    const component = shallow(<LandingPage/>);
+    expect(component).toMatchSnapshot();
+  });
+test('renders the CommitListPage', () => {
+    const component = shallow(<CommitPageWrapper/>);
+    expect(component).toMatchSnapshot();
+  });
+test('renders the CommitGraphPage', () => {
+    const component = shallow(<CommitPage/>);
+    expect(component).toMatchSnapshot();
+  });
+
+