[Performance] VirtualizedSelect for SelectControl and FilterBox (#3654)

* Added virtualized select to SelectControl, allow onPaste to create new options

* Added unit tests

* Added virtualized/paste select to filterbox

superset/assets/spec/javascripts/components/VirtualizedRendererWrap_spec.jsx

@@ -0,0 +1,106 @@
+/* eslint-disable no-unused-expressions */
+import React from 'react';
+import sinon from 'sinon';
+import PropTypes from 'prop-types';
+import { expect } from 'chai';
+import { describe, it } from 'mocha';
+import { shallow } from 'enzyme';
+
+import VirtualizedRendererWrap from '../../../javascripts/components/VirtualizedRendererWrap';
+
+const defaultProps = {
+  focusedOption: { label: 'focusedOn', value: 'focusedOn' },
+  focusOption: sinon.spy(),
+  key: 'key1',
+  option: { label: 'option1', value: 'option1' },
+  selectValue: sinon.spy(),
+  valueArray: [],
+};
+
+function TestOption({ option }) {
+  return (
+    <span>{option.label}</span>
+  );
+}
+TestOption.propTypes = {
+  option: PropTypes.object.isRequired,
+};
+
+const defaultRenderer = opt => <TestOption option={opt} />;
+const RendererWrap = VirtualizedRendererWrap(defaultRenderer);
+
+describe('VirtualizedRendererWrap', () => {
+  let wrapper;
+  let props;
+  beforeEach(() => {
+    wrapper = shallow(<RendererWrap {...defaultProps} />);
+    props = Object.assign({}, defaultProps);
+  });
+
+  it('uses the provided renderer', () => {
+    const option = wrapper.find(TestOption);
+    expect(option).to.have.lengthOf(1);
+  });
+
+  it('renders nothing when no option is provided', () => {
+    props.option = null;
+    wrapper = shallow(<RendererWrap {...props} />);
+    const option = wrapper.find(TestOption);
+    expect(option).to.have.lengthOf(0);
+  });
+
+  it('renders unfocused, unselected options with the default class', () => {
+    const optionDiv = wrapper.find('div');
+    expect(optionDiv).to.have.lengthOf(1);
+    expect(optionDiv.props().className).to.equal('VirtualizedSelectOption');
+  });
+
+  it('renders focused option with the correct class', () => {
+    props.option = props.focusedOption;
+    wrapper = shallow(<RendererWrap {...props} />);
+    const optionDiv = wrapper.find('div');
+    expect(optionDiv.props().className).to.equal(
+      'VirtualizedSelectOption VirtualizedSelectFocusedOption',
+    );
+  });
+
+  it('renders disabled option with the correct class', () => {
+    props.option.disabled = true;
+    wrapper = shallow(<RendererWrap {...props} />);
+    const optionDiv = wrapper.find('div');
+    expect(optionDiv.props().className).to.equal(
+      'VirtualizedSelectOption VirtualizedSelectDisabledOption',
+    );
+    props.option.disabled = false;
+  });
+
+  it('renders selected option with the correct class', () => {
+    props.valueArray = [props.option, props.focusedOption];
+    wrapper = shallow(<RendererWrap {...props} />);
+    const optionDiv = wrapper.find('div');
+    expect(optionDiv.props().className).to.equal(
+      'VirtualizedSelectOption VirtualizedSelectSelectedOption',
+    );
+  });
+
+  it('renders options with custom classes', () => {
+    props.option.className = 'CustomClass';
+    wrapper = shallow(<RendererWrap {...props} />);
+    const optionDiv = wrapper.find('div');
+    expect(optionDiv.props().className).to.equal(
+      'VirtualizedSelectOption CustomClass',
+    );
+  });
+
+  it('calls focusedOption on its own option onMouseEnter', () => {
+    const optionDiv = wrapper.find('div');
+    optionDiv.simulate('mouseEnter');
+    expect(props.focusOption.calledWith(props.option)).to.be.true;
+  });
+
+  it('calls selectValue on its own option onClick', () => {
+    const optionDiv = wrapper.find('div');
+    optionDiv.simulate('click');
+    expect(props.selectValue.calledWith(props.option)).to.be.true;
+  });
+});