Remove old namespace select dropdown implementation

app/assets/javascripts/namespace_select.js

-import $ from 'jquery';
-import initDeprecatedJQueryDropdown from '~/deprecated_jquery_dropdown';
-import { parseBoolean } from '~/lib/utils/common_utils';
-import Api from './api';
-import { mergeUrlParams } from './lib/utils/url_utility';
-import { __ } from './locale';
-
-export default class NamespaceSelect {
-  constructor(opts) {
-    const isFilter = parseBoolean(opts.dropdown.dataset.isFilter);
-    const fieldName = opts.dropdown.dataset.fieldName || 'namespace_id';
-
-    initDeprecatedJQueryDropdown($(opts.dropdown), {
-      filterable: true,
-      selectable: true,
-      filterRemote: true,
-      search: {
-        fields: ['path'],
-      },
-      fieldName,
-      toggleLabel(selected) {
-        if (selected.id == null) {
-          return selected.text;
-        }
-        return `${selected.kind}: ${selected.full_path}`;
-      },
-      data(term, dataCallback) {
-        return Api.namespaces(term, (namespaces) => {
-          if (isFilter) {
-            const anyNamespace = {
-              text: __('Any namespace'),
-              id: null,
-            };
-            namespaces.unshift(anyNamespace);
-            namespaces.splice(1, 0, { type: 'divider' });
-          }
-          return dataCallback(namespaces);
-        });
-      },
-      text(namespace) {
-        if (namespace.id == null) {
-          return namespace.text;
-        }
-        return `${namespace.kind}: ${namespace.full_path}`;
-      },
-      renderRow: this.renderRow,
-      clicked(options) {
-        if (!isFilter) {
-          const { e } = options;
-          e.preventDefault();
-        }
-      },
-      url(namespace) {
-        return mergeUrlParams({ [fieldName]: namespace.id }, window.location.href);
-      },
-    });
-  }
-}

spec/frontend/namespace_select_spec.js

-import initDeprecatedJQueryDropdown from '~/deprecated_jquery_dropdown';
-import NamespaceSelect from '~/namespace_select';
-
-jest.mock('~/deprecated_jquery_dropdown');
-
-describe('NamespaceSelect', () => {
-  it('initializes deprecatedJQueryDropdown', () => {
-    const dropdown = document.createElement('div');
-
-    // eslint-disable-next-line no-new
-    new NamespaceSelect({ dropdown });
-
-    expect(initDeprecatedJQueryDropdown).toHaveBeenCalled();
-  });
-
-  describe('as input', () => {
-    let deprecatedJQueryDropdownOptions;
-
-    beforeEach(() => {
-      const dropdown = document.createElement('div');
-      // eslint-disable-next-line no-new
-      new NamespaceSelect({ dropdown });
-      [[, deprecatedJQueryDropdownOptions]] = initDeprecatedJQueryDropdown.mock.calls;
-    });
-
-    it('prevents click events', () => {
-      const dummyEvent = new Event('dummy');
-      jest.spyOn(dummyEvent, 'preventDefault').mockImplementation(() => {});
-
-      // expect(foo).toContain('test');
-      deprecatedJQueryDropdownOptions.clicked({ e: dummyEvent });
-
-      expect(dummyEvent.preventDefault).toHaveBeenCalled();
-    });
-  });
-
-  describe('as filter', () => {
-    let deprecatedJQueryDropdownOptions;
-
-    beforeEach(() => {
-      const dropdown = document.createElement('div');
-      dropdown.dataset.isFilter = 'true';
-      // eslint-disable-next-line no-new
-      new NamespaceSelect({ dropdown });
-      [[, deprecatedJQueryDropdownOptions]] = initDeprecatedJQueryDropdown.mock.calls;
-    });
-
-    it('does not prevent click events', () => {
-      const dummyEvent = new Event('dummy');
-      jest.spyOn(dummyEvent, 'preventDefault').mockImplementation(() => {});
-
-      deprecatedJQueryDropdownOptions.clicked({ e: dummyEvent });
-
-      expect(dummyEvent.preventDefault).not.toHaveBeenCalled();
-    });
-
-    it('sets URL of dropdown items', () => {
-      const dummyNamespace = { id: 'eal' };
-
-      const itemUrl = deprecatedJQueryDropdownOptions.url(dummyNamespace);
-
-      expect(itemUrl).toContain(`namespace_id=${dummyNamespace.id}`);
-    });
-  });
-});