Add Unit Test to ToolbarIcon

Summary: per title

Reviewed By: mweststrate

Differential Revision: D21663253

fbshipit-source-id: de1eff5a3500473082973a27d0b72479407cbebe

desktop/app/src/ui/components/__tests__/ToolbarIcon.node.tsx

@@ -0,0 +1,74 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import React from 'react';
+import {render, fireEvent} from '@testing-library/react';
+
+import ToolbarIcon from '../ToolbarIcon';
+import TooltipProvider from '../TooltipProvider';
+
+const TITLE_STRING = 'This is for testing';
+
+test('rendering element icon without hovering', () => {
+  const res = render(
+    <ToolbarIcon title={TITLE_STRING} icon="target" onClick={() => {}} />,
+  );
+  expect(res.queryAllByText(TITLE_STRING).length).toBe(0);
+});
+
+test('trigger active for coverage(?)', () => {
+  const res = render(
+    <ToolbarIcon title={TITLE_STRING} icon="target" onClick={() => {}} />,
+  );
+  res.rerender(
+    <ToolbarIcon
+      active
+      title={TITLE_STRING}
+      icon="target"
+      onClick={() => {}}
+    />,
+  );
+  res.rerender(
+    <ToolbarIcon title={TITLE_STRING} icon="target" onClick={() => {}} />,
+  );
+});
+
+test('test on hover and unhover', () => {
+  const res = render(
+    <TooltipProvider>
+      <ToolbarIcon title={TITLE_STRING} icon="target" onClick={() => {}} />
+    </TooltipProvider>,
+  );
+  expect(res.queryAllByText(TITLE_STRING).length).toBe(0);
+
+  const comp = res.container.firstChild?.childNodes[0];
+  expect(comp).not.toBeNull();
+
+  // hover
+  fireEvent.mouseEnter(comp!);
+  expect(res.queryAllByText(TITLE_STRING).length).toBe(1);
+  // unhover
+  fireEvent.mouseLeave(comp!);
+  expect(res.queryAllByText(TITLE_STRING).length).toBe(0);
+});
+
+test('test on click', () => {
+  const mockOnClick = jest.fn(() => {});
+  const res = render(
+    <TooltipProvider>
+      <ToolbarIcon title={TITLE_STRING} icon="target" onClick={mockOnClick} />
+    </TooltipProvider>,
+  );
+  const comp = res.container.firstChild?.childNodes[0];
+  expect(comp).not.toBeNull();
+
+  // click
+  fireEvent.click(comp!);
+  expect(mockOnClick.mock.calls.length).toBe(1);
+});