fix(poll): keep translations from poll.updated in the poll state

src/poll.ts

@@ -158,7 +158,15 @@ export class Poll {
     const { id: _id, ...pollData } = extractPollData(event.poll);
     if (pollData.is_closed) this.closeConfirmed = true;
     // @ts-expect-error type mismatch
-    this.state.partialNext({ ...pollData, lastActivityAt: event.created_at });
+    this.state.partialNext({
+      ...pollData,
+      // Server-owned translations, which `extractPollData` (an update request) leaves out. Copied
+      // even when absent: the event carries the whole poll, and a change made under channel-only
+      // translation drops the stale ones.
+      description_i18n: event.poll.description_i18n,
+      lastActivityAt: event.created_at,
+      name_i18n: event.poll.name_i18n,
+    });
     this.upsertOfflineDb();
   };
 

test/unit/poll.test.js

@@ -188,6 +188,66 @@
 		expect(poll.data.description).to.equal(description);
 	});
 
+	describe('translations on poll.updated', () => {
+		const nameI18n = { en_text: 'XY', es_text: 'XY (es)', language: 'en' };
+		const descriptionI18n = { en_text: 'About', es_text: 'Acerca de', language: 'en' };
+
+		it('stores the translations of an edited question', () => {
+			const poll = new Poll({ client, poll: { ...pollResponse, name_i18n: nameI18n } });
+			const editedNameI18n = { en_text: 'XYZ', es_text: 'XYZ (es)', language: 'en' };
+
+			poll.handlePollUpdated({
+				type: 'poll.updated',
+				poll: { ...pollResponse, name: 'XYZ', name_i18n: editedNameI18n },
+			});
+
+			expect(poll.data.name).to.equal('XYZ');
+			expect(poll.data.name_i18n).to.eql(editedNameI18n);
+		});
+
+		it('stores a language added after the poll was sent', () => {
+			const poll = new Poll({ client, poll: { ...pollResponse, name_i18n: nameI18n } });
+			const withGerman = { ...nameI18n, de_text: 'XY (de)' };
+
+			poll.handlePollUpdated({
+				type: 'poll.updated',
+				poll: { ...pollResponse, name_i18n: withGerman },
+			});
+
+			expect(poll.data.name_i18n).to.eql(withGerman);
+		});
+
+		it('stores the translations of the description', () => {
+			const poll = new Poll({ client, poll: pollResponse });
+
+			poll.handlePollUpdated({
+				type: 'poll.updated',
+				poll: {
+					...pollResponse,
+					description: 'About',
+					description_i18n: descriptionI18n,
+				},
+			});
+
+			expect(poll.data.description_i18n).to.eql(descriptionI18n);
+		});
+
+		it('clears translations the event no longer carries', () => {
+			const poll = new Poll({
+				client,
+				poll: { ...pollResponse, description_i18n: descriptionI18n, name_i18n: nameI18n },
+			});
+
+			poll.handlePollUpdated({
+				type: 'poll.updated',
+				poll: { ...pollResponse, name: 'XYZ' },
+			});
+
+			expect(poll.data.name_i18n).to.be.undefined;
+			expect(poll.data.description_i18n).to.be.undefined;
+		});
+	});
+
 	it("should not update poll state when handlePollUpdated is called with other poll's event", () => {
 		const poll = new Poll({ client, poll: { ...pollResponse, id: 'X' } });
 		const description = 'Description update';
@@ -1653,7 +1713,7 @@
 				expect(poll.data.ownVotesByOptionId[optionD]).toBeUndefined();
 
 				// the removal's event is lost too, so the failed vote stays shown until the timeout
 				slowRequest.reject(new Error('failed'));
 				await vi.advanceTimersByTimeAsync(0);
 				expect(poll.data.ownVotesByOptionId[optionC].id).toMatch(/^local-/);
 

test/unit/poll_manager.test.ts

@@ -589,6 +589,21 @@ describe('PollManager', () => {
       expect(spy2.calledOnce).to.be.false;
     });
 
+    it('should keep the translations of poll.updated in the cached poll', () => {
+      const nameI18n = { de_text: 'Neuer Titel', en_text: 'New title', language: 'en' };
+
+      client.dispatchEvent({
+        type: 'poll.updated',
+        poll: {
+          ...pollMessage1.poll,
+          name: 'New title',
+          name_i18n: nameI18n,
+        } as PollResponse,
+      });
+
+      expect(pollManager.fromState(pollId1)?.data.name_i18n).to.eql(nameI18n);
+    });
+
     const eventHandlerPairs = [
       ['poll.closed', 'handlePollClosed'],
       ['poll.vote_casted', 'handleVoteCasted'],