Grafana/ui: display all selected levels for Cascader (#31729)

* add support for displaying all selected levels for cascader

* add story for Cascader with display all selected levels

* add tests for Cascader with displayAllSelectedLevels prop

* replace enzyme test with RTL for cascader

packages/grafana-ui/src/components/Cascader/Cascader.story.tsx

@@ -59,6 +59,7 @@ export const Simple = Template.bind({});
 Simple.args = {
   separator: '',
 };
+
 export const WithInitialValue = Template.bind({});
 WithInitialValue.args = {
   initialValue: '3',
@@ -70,3 +71,9 @@ WithCustomValue.args = {
   allowCustomValue: true,
   formatCreateLabel: (val) => 'Custom Label' + val,
 };
+
+export const WithDisplayAllSelectedLevels = Template.bind({});
+WithDisplayAllSelectedLevels.args = {
+  displayAllSelectedLevels: true,
+  separator: ',',
+};

packages/grafana-ui/src/components/Cascader/Cascader.test.tsx

@@ -1,6 +1,7 @@
 import React from 'react';
 import { Cascader } from './Cascader';
-import { shallow } from 'enzyme';
+import { render, screen } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
 
 const options = [
   {
@@ -27,36 +28,73 @@ const options = [
   },
 ];
 
-const flatOptions = [
-  {
-    singleLabel: 'Second',
-    label: 'First / Second',
-    value: ['1', '2'],
-  },
-  {
-    singleLabel: 'Third',
-    label: 'First / Third',
-    value: ['1', '3'],
-  },
-  {
-    singleLabel: 'Fourth',
-    label: 'First / Fourth',
-    value: ['1', '4'],
-  },
-  {
-    singleLabel: 'FirstFirst',
-    label: 'FirstFirst',
-    value: ['5'],
-  },
-];
-
 describe('Cascader', () => {
-  let cascader: any;
-  beforeEach(() => {
-    cascader = shallow(<Cascader options={options} onSelect={() => {}} />);
+  const placeholder = 'cascader-placeholder';
+
+  it('filters results when searching', () => {
+    render(<Cascader placeholder={placeholder} options={options} onSelect={() => {}} />);
+
+    userEvent.type(screen.getByPlaceholderText(placeholder), 'Third');
+
+    expect(screen.queryByText('Second')).not.toBeInTheDocument();
+    expect(screen.getByText('First / Third')).toBeInTheDocument();
   });
 
-  it('Should convert options to searchable strings', () => {
-    expect(cascader.state('searchableOptions')).toEqual(flatOptions);
+  it('displays all levels selected with default separator when displayAllSelectedLevels is true', () => {
+    render(
+      <Cascader displayAllSelectedLevels={true} placeholder={placeholder} options={options} onSelect={() => {}} />
+    );
+
+    expect(screen.queryByDisplayValue('First/Second')).not.toBeInTheDocument();
+
+    userEvent.click(screen.getByPlaceholderText(placeholder));
+    userEvent.click(screen.getByText('First'));
+    userEvent.click(screen.getByText('Second'));
+
+    expect(screen.getByDisplayValue('First/Second')).toBeInTheDocument();
+  });
+
+  it('displays all levels selected with separator passed in when displayAllSelectedLevels is true', () => {
+    const separator = ',';
+
+    render(
+      <Cascader
+        displayAllSelectedLevels={true}
+        separator={separator}
+        placeholder={placeholder}
+        options={options}
+        onSelect={() => {}}
+      />
+    );
+
+    expect(screen.queryByDisplayValue('First/Second')).not.toBeInTheDocument();
+
+    userEvent.click(screen.getByPlaceholderText(placeholder));
+    userEvent.click(screen.getByText('First'));
+    userEvent.click(screen.getByText('Second'));
+
+    expect(screen.getByDisplayValue(`First${separator}Second`)).toBeInTheDocument();
+  });
+
+  it('displays last level selected when displayAllSelectedLevels is false', () => {
+    render(
+      <Cascader displayAllSelectedLevels={false} placeholder={placeholder} options={options} onSelect={() => {}} />
+    );
+
+    userEvent.click(screen.getByPlaceholderText(placeholder));
+    userEvent.click(screen.getByText('First'));
+    userEvent.click(screen.getByText('Second'));
+
+    expect(screen.getByDisplayValue('Second')).toBeInTheDocument();
+  });
+
+  it('displays last level selected when displayAllSelectedLevels is not passed in', () => {
+    render(<Cascader placeholder={placeholder} options={options} onSelect={() => {}} />);
+
+    userEvent.click(screen.getByPlaceholderText(placeholder));
+    userEvent.click(screen.getByText('First'));
+    userEvent.click(screen.getByText('Second'));
+
+    expect(screen.getByDisplayValue('Second')).toBeInTheDocument();
   });
 });

packages/grafana-ui/src/components/Cascader/Cascader.tsx

@@ -22,6 +22,7 @@ export interface CascaderProps {
   allowCustomValue?: boolean;
   /** A function for formatting the message for custom value creation. Only applies when allowCustomValue is set to true*/
   formatCreateLabel?: (val: string) => string;
+  displayAllSelectedLevels?: boolean;
 }
 
 interface CascaderState {
@@ -57,6 +58,8 @@ const disableDivFocus = css(`
 }
 `);
 
+const DEFAULT_SEPARATOR = '/';
+
 export class Cascader extends React.PureComponent<CascaderProps, CascaderState> {
   constructor(props: CascaderProps) {
     super(props);
@@ -81,7 +84,7 @@ export class Cascader extends React.PureComponent<CascaderProps, CascaderState>
       if (!option.items) {
         selectOptions.push({
           singleLabel: cpy[cpy.length - 1].label,
-          label: cpy.map((o) => o.label).join(this.props.separator || ' / '),
+          label: cpy.map((o) => o.label).join(this.props.separator || ` ${DEFAULT_SEPARATOR} `),
           value: cpy.map((o) => o.value),
         });
       } else {
@@ -116,7 +119,9 @@ export class Cascader extends React.PureComponent<CascaderProps, CascaderState>
     this.setState({
       rcValue: value,
       focusCascade: true,
-      activeLabel: selectedOptions[selectedOptions.length - 1].label,
+      activeLabel: this.props.displayAllSelectedLevels
+        ? selectedOptions.map((option) => option.label).join(this.props.separator || DEFAULT_SEPARATOR)
+        : selectedOptions[selectedOptions.length - 1].label,
     });
 
     this.props.onSelect(selectedOptions[selectedOptions.length - 1].value);