test: add test for markdown description rendering in EntityPicker

Signed-off-by: Toby Harradine <tobyh@canva.com>

plugins/scaffolder/src/components/fields/EntityPicker/EntityPicker.test.tsx

@@ -28,6 +28,13 @@ import { EntityPickerProps } from './schema';
 import { ScaffolderRJSFFieldProps as FieldProps } from '@backstage/plugin-scaffolder-react';
 import { DefaultEntityPresentationApi } from '@backstage/plugin-catalog';
 import { catalogApiMock } from '@backstage/plugin-catalog-react/testUtils';
+import * as backstageCore from '@backstage/core-components';
+
+// Mock MarkdownContent to test that it's called with the right props
+jest.mock('@backstage/core-components', () => ({
+  ...jest.requireActual('@backstage/core-components'),
+  MarkdownContent: jest.fn(() => null),
+}));
 
 const makeEntity = (kind: string, namespace: string, name: string): Entity => ({
   apiVersion: 'scaffolder.backstage.io/v1beta3',
@@ -812,4 +819,39 @@ describe('<EntityPicker />', () => {
       expect(onChange).toHaveBeenCalledWith(undefined);
     });
   });
+
+  describe('with markdown description', () => {
+    beforeEach(() => {
+      jest.clearAllMocks();
+      uiSchema = { 'ui:options': {} };
+      props = {
+        onChange,
+        schema: {
+          description: '**Bold text** and *italic text*',
+        },
+        required,
+        uiSchema,
+        rawErrors,
+        formData,
+      } as unknown as FieldProps;
+
+      catalogApi.getEntities.mockResolvedValue({ items: entities });
+    });
+
+    it('renders description as markdown', async () => {
+      await renderInTestApp(
+        <Wrapper>
+          <EntityPicker {...props} />
+        </Wrapper>,
+      );
+
+      expect(backstageCore.MarkdownContent).toHaveBeenCalledWith(
+        expect.objectContaining({
+          content: '**Bold text** and *italic text*',
+          linkTarget: '_blank',
+        }),
+        expect.anything(),
+      );
+    });
+  });
 });