[Discover] Dont trigger onChange when the same index pattern is selected (#102652)

src/plugins/discover/public/application/apps/main/components/sidebar/change_indexpattern.test.tsx

@@ -0,0 +1,71 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+import React from 'react';
+import { EuiSelectable } from '@elastic/eui';
+import { ShallowWrapper } from 'enzyme';
+import { act } from 'react-dom/test-utils';
+import { shallowWithIntl } from '@kbn/test/jest';
+import { ChangeIndexPattern } from './change_indexpattern';
+import { indexPatternMock } from '../../../../../__mocks__/index_pattern';
+import { indexPatternWithTimefieldMock } from '../../../../../__mocks__/index_pattern_with_timefield';
+import { IndexPatternRef } from './types';
+
+function getProps() {
+  return {
+    indexPatternId: indexPatternMock.id,
+    indexPatternRefs: [
+      indexPatternMock as IndexPatternRef,
+      indexPatternWithTimefieldMock as IndexPatternRef,
+    ],
+    onChangeIndexPattern: jest.fn(),
+    trigger: {
+      label: indexPatternMock.title,
+      title: indexPatternMock.title,
+      'data-test-subj': 'indexPattern-switch-link',
+    },
+  };
+}
+
+function getIndexPatternPickerList(instance: ShallowWrapper) {
+  return instance.find(EuiSelectable).first();
+}
+
+function getIndexPatternPickerOptions(instance: ShallowWrapper) {
+  return getIndexPatternPickerList(instance).prop('options');
+}
+
+export function selectIndexPatternPickerOption(instance: ShallowWrapper, selectedLabel: string) {
+  const options: Array<{ label: string; checked?: 'on' | 'off' }> = getIndexPatternPickerOptions(
+    instance
+  ).map((option: { label: string }) =>
+    option.label === selectedLabel
+      ? { ...option, checked: 'on' }
+      : { ...option, checked: undefined }
+  );
+  return getIndexPatternPickerList(instance).prop('onChange')!(options);
+}
+
+describe('ChangeIndexPattern', () => {
+  test('switching index pattern to the same index pattern does not trigger onChangeIndexPattern', async () => {
+    const props = getProps();
+    const comp = shallowWithIntl(<ChangeIndexPattern {...props} />);
+    await act(async () => {
+      selectIndexPatternPickerOption(comp, indexPatternMock.title);
+    });
+    expect(props.onChangeIndexPattern).toHaveBeenCalledTimes(0);
+  });
+  test('switching index pattern to a different index pattern triggers onChangeIndexPattern', async () => {
+    const props = getProps();
+    const comp = shallowWithIntl(<ChangeIndexPattern {...props} />);
+    await act(async () => {
+      selectIndexPatternPickerOption(comp, indexPatternWithTimefieldMock.title);
+    });
+    expect(props.onChangeIndexPattern).toHaveBeenCalledTimes(1);
+    expect(props.onChangeIndexPattern).toHaveBeenCalledWith(indexPatternWithTimefieldMock.id);
+  });
+});

src/plugins/discover/public/application/apps/main/components/sidebar/change_indexpattern.tsx

@@ -26,17 +26,17 @@ export type ChangeIndexPatternTriggerProps = EuiButtonProps & {
 // TODO: refactor to shared component with ../../../../../../../../x-pack/legacy/plugins/lens/public/indexpattern_plugin/change_indexpattern
 
 export function ChangeIndexPattern({
-  indexPatternRefs,
   indexPatternId,
+  indexPatternRefs,
   onChangeIndexPattern,
-  trigger,
   selectableProps,
+  trigger,
 }: {
-  trigger: ChangeIndexPatternTriggerProps;
+  indexPatternId?: string;
   indexPatternRefs: IndexPatternRef[];
   onChangeIndexPattern: (newId: string) => void;
-  indexPatternId?: string;
   selectableProps?: EuiSelectableProps<{ value: string }>;
+  trigger: ChangeIndexPatternTriggerProps;
 }) {
   const [isPopoverOpen, setPopoverIsOpen] = useState(false);
 
@@ -86,7 +86,9 @@ export function ChangeIndexPattern({
             const choice = (choices.find(({ checked }) => checked) as unknown) as {
               value: string;
             };
-            onChangeIndexPattern(choice.value);
+            if (choice.value !== indexPatternId) {
+              onChangeIndexPattern(choice.value);
+            }
             setPopoverIsOpen(false);
           }}
           searchProps={{