Device manager - current session expandable details (PSG-644) (#9185)

* split current device section into component

* add dropdown button for currentsession device details

* test currentdevicesection

* remove unnecc beforeEach

* update type imports

* i18n and lint

test/components/views/settings/devices/DeviceExpandDetailsButton-test.tsx

@@ -0,0 +1,47 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import React from 'react';
+import { fireEvent, render } from '@testing-library/react';
+
+import DeviceExpandDetailsButton from '../../../../../src/components/views/settings/devices/DeviceExpandDetailsButton';
+
+describe('<DeviceExpandDetailsButton />', () => {
+    const defaultProps = {
+        isExpanded: false,
+        onClick: jest.fn(),
+    };
+    const getComponent = (props = {}) =>
+        <DeviceExpandDetailsButton {...defaultProps} {...props} />;
+
+    it('renders when not expanded', () => {
+        const { container } = render(getComponent());
+        expect({ container }).toMatchSnapshot();
+    });
+
+    it('renders when expanded', () => {
+        const { container } = render(getComponent({ isExpanded: true }));
+        expect({ container }).toMatchSnapshot();
+    });
+
+    it('calls onClick', () => {
+        const onClick = jest.fn();
+        const { getByTestId } = render(getComponent({ 'data-testid': 'test', onClick }));
+        fireEvent.click(getByTestId('test'));
+
+        expect(onClick).toHaveBeenCalled();
+    });
+});