fix(InputNumber): make plus/minus buttons un-focusable

src/InputNumber/InputNumber.tsx

@@ -300,6 +300,7 @@ const InputNumber = React.forwardRef((props: InputNumberProps, ref) => {
       {input}
       <span className={prefix('btn-group-vertical')}>
         <Button
+          tabIndex={-1}
           appearance={buttonAppearance}
           className={prefix('touchspin-up')}
           onClick={handlePlus}
@@ -308,6 +309,7 @@ const InputNumber = React.forwardRef((props: InputNumberProps, ref) => {
           <AngleUpIcon />
         </Button>
         <Button
+          tabIndex={-1}
           appearance={buttonAppearance}
           className={prefix('touchspin-down')}
           onClick={handleMinus}

src/InputNumber/test/InputNumberSpec.js

@@ -1,5 +1,6 @@
 import React from 'react';
 import { render, fireEvent } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
 import ReactTestUtils, { act } from 'react-dom/test-utils';
 import { getDOMNode } from '@test/testUtils';
 import { testStandardProps } from '@test/commonCases';
@@ -191,6 +192,18 @@ describe('InputNumber', () => {
       expect(getByRole('spinbutton')).to.exist;
     });
 
+    it('Should not have focusable elements other than the input', () => {
+      const { container } = render(<InputNumber value={0} />);
+
+      // Move focus to the input
+      userEvent.tab();
+
+      // Move focus out
+      userEvent.tab();
+
+      expect(container).not.to.contain(document.activeElement);
+    });
+
     describe('Keyboard interaction', () => {
       it('Should increase the value when ArrowUp is pressed', () => {
         const onChange = sinon.spy();