Fix html export when feature_jump_to_date is enabled (#30828)

* Fix html export when feature_jump_to_date is enabled

* Fix tests and lint

src/components/views/messages/DateSeparator.tsx

@@ -320,7 +320,7 @@ export default class DateSeparator extends React.Component<IProps, IState> {
         const label = this.getLabel();
 
         let dateHeaderContent: JSX.Element;
-        if (this.state.jumpToDateEnabled) {
+        if (this.state.jumpToDateEnabled && !this.props.forExport) {
             dateHeaderContent = this.renderJumpToDateMenu();
         } else {
             dateHeaderContent = (

test/unit-tests/utils/exportUtils/HTMLExport-test.ts

@@ -23,6 +23,7 @@ import {
 import fetchMock from "fetch-mock-jest";
 import escapeHtml from "escape-html";
 import { type RelationsContainer } from "matrix-js-sdk/src/models/relations-container";
+import { mocked } from "jest-mock";
 
 import { filterConsole, mkReaction, mkStubRoom, REPEATABLE_DATE, stubClient } from "../../../test-utils";
 import { ExportType, type IExportOptions } from "../../../../src/utils/exportUtils/exportUtils";
@@ -30,8 +31,10 @@ import SdkConfig from "../../../../src/SdkConfig";
 import HTMLExporter from "../../../../src/utils/exportUtils/HtmlExport";
 import DMRoomMap from "../../../../src/utils/DMRoomMap";
 import { mediaFromMxc } from "../../../../src/customisations/Media";
+import SettingsStore from "../../../../src/settings/SettingsStore";
 
 jest.mock("jszip");
+jest.mock("../../../../src/settings/SettingsStore");
 
 const EVENT_MESSAGE: IRoomEvent = {
     event_id: "$1",
@@ -88,6 +91,7 @@ describe("HTMLExport", () => {
     );
 
     beforeEach(() => {
+        jest.clearAllMocks();
         jest.useFakeTimers();
         jest.setSystemTime(REPEATABLE_DATE);
 
@@ -96,6 +100,13 @@ describe("HTMLExport", () => {
 
         room = new Room("!myroom:example.org", client, "@me:example.org");
         client.getRoom.mockReturnValue(room);
+
+        // Set up a default mock that uses the actual SettingsStore implementation
+        const actualSettingsStore = jest.requireActual("../../../../src/settings/SettingsStore").default;
+        mocked(SettingsStore).getValue.mockImplementation((name: any, roomId?: any, excludeDefault?: any): any => {
+            // Default to the real implementation
+            return actualSettingsStore.getValue(name, roomId, excludeDefault);
+        });
     });
 
     function mockMessages(...events: IRoomEvent[]): void {
@@ -675,4 +686,34 @@ describe("HTMLExport", () => {
         const file = getMessageFile(exporter);
         expect(await file.text()).toContain(reaction.getContent()["m.relates_to"]?.key);
     });
+
+    it("should not crash when jump to date flag is enabled", async () => {
+        // Override just the feature flag for this specific test
+        const originalMock = mocked(SettingsStore).getValue.getMockImplementation();
+
+        mocked(SettingsStore).getValue.mockImplementation((name: any, roomId?: any, excludeDefault?: any): any => {
+            if (name === "feature_jump_to_date") {
+                return true;
+            }
+            // Fallback to the default mock implementation set in beforeEach
+            return originalMock!(name, roomId, excludeDefault);
+        });
+
+        mockMessages(EVENT_MESSAGE);
+        const exporter = new HTMLExporter(
+            room,
+            ExportType.LastNMessages,
+            {
+                attachmentsIncluded: false,
+                maxSize: 1_024 * 1_024,
+                numberOfMessages: 40,
+            },
+            () => {},
+        );
+
+        await exporter.export();
+
+        const file = getMessageFile(exporter);
+        expect(file).not.toBeUndefined();
+    });
 });