tane/apps/app_seeds/test/state/offers_cubit_test.dart
vjrj f17ae7751c perf(market): paginate Nostr offer discovery, infinite scroll, memory cap
Bound market memory and let large areas page instead of loading everything:
- DiscoveryQuery gains an until cursor; OfferTransport gains discoverPage()
  (one-shot, EOSE-bounded, newest-first) alongside the existing live discover()
  stream, which now accepts since so it only carries NEW offers going forward.
- NostrOfferTransport.discoverPage sorts by created_at desc and derives the
  next cursor from the oldest event seen (not the oldest type-matched one, so
  filtering never skips a page).
- OffersCubit: discover() fetches the first page + opens a since=now live sub;
  loadNextPage() pages further back; the in-memory list is capped at 400
  offers (each can carry a ~40KB inline photo thumbnail, so unbounded growth in
  a busy area was a real OOM risk).
- market_screen: infinite scroll via a scroll-position trigger + footer
  spinner, instead of a single unbounded ListView.
- Added discoverPage unit tests (commons_core) and cubit pagination tests
  (first page/cursor, accumulation, cap, cross-page dedup).
2026-07-20 22:53:48 +02:00

838 lines
27 KiB
Dart

import 'dart:async';
import 'dart:typed_data';
import 'package:commons_core/commons_core.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:tane/data/variety_repository.dart';
import 'package:tane/db/enums.dart';
import 'package:tane/services/discovery_area.dart';
import 'package:tane/services/offer_mapper.dart';
import 'package:tane/services/offer_outbox.dart';
import 'package:tane/state/offers_cubit.dart';
import '../support/test_support.dart';
/// In-memory [OfferTransport] for tests: addressable by id, discover matches by
/// geohash prefix. No relay, no network.
class FakeOfferTransport implements OfferTransport {
final List<Offer> _offers = [];
@override
Future<PublishResult> publish(Offer offer) async {
_offers.removeWhere((o) => o.id == offer.id);
_offers.add(offer);
return PublishResult(accepted: true, transportRef: offer.id);
}
@override
Stream<Offer> discover(DiscoveryQuery query, {int? since}) {
final controller = StreamController<Offer>();
for (final o in _offers) {
if (o.approxGeohash.startsWith(query.geohashPrefix)) controller.add(o);
}
return controller.stream; // left open (live), like a real subscription
}
@override
Future<OfferPage> discoverPage(DiscoveryQuery query) async {
final matches = [
for (final o in _offers)
if (o.approxGeohash.startsWith(query.geohashPrefix)) o,
];
return OfferPage(offers: matches); // short page → nothing older to load
}
@override
Future<void> retract(String offerId) async =>
_offers.removeWhere((o) => o.id == offerId);
@override
Future<void> close() async {}
}
/// Emits every published offer TWICE on discover — the way a relay legitimately
/// resends an addressable event (a stored copy plus a live echo). Used to prove
/// the cubit dedups instead of doubling the listing.
class DuplicatingOfferTransport implements OfferTransport {
final List<Offer> _offers = [];
@override
Future<PublishResult> publish(Offer offer) async {
_offers.add(offer);
return PublishResult(accepted: true, transportRef: offer.id);
}
@override
Stream<Offer> discover(DiscoveryQuery query, {int? since}) {
final controller = StreamController<Offer>();
for (final o in _offers) {
if (o.approxGeohash.startsWith(query.geohashPrefix)) {
controller.add(o);
controller.add(o); // the duplicate
}
}
return controller.stream;
}
@override
Future<OfferPage> discoverPage(DiscoveryQuery query) async {
// The stored copy (deduped at relay level); the live echo (the duplicate)
// still arrives via [discover], so the cubit's dedup is what's under test.
final matches = [
for (final o in _offers)
if (o.approxGeohash.startsWith(query.geohashPrefix)) o,
];
return OfferPage(offers: matches);
}
@override
Future<void> retract(String offerId) async =>
_offers.removeWhere((o) => o.id == offerId);
@override
Future<void> close() async {}
}
/// A transport that serves offers in `until`-cursored pages (like a relay's
/// stored events), so the cubit's pagination and memory cap can be exercised.
/// Each seeded offer gets a descending createdAt; [discover] (live) is empty.
class PaginatingOfferTransport implements OfferTransport {
PaginatingOfferTransport(int count, {this.geohash = 'sp3e9'}) {
// Newest (highest createdAt) first: offer 0 is newest.
for (var i = 0; i < count; i++) {
_byCreatedAt.add((
createdAt: 1000000 - i,
offer: Offer(
id: 'o$i',
authorPubkeyHex: 'ab' * 32,
summary: 'offer $i',
type: OfferType.gift,
approxGeohash: geohash,
),
));
}
}
final String geohash;
final List<({int createdAt, Offer offer})> _byCreatedAt = [];
@override
Stream<Offer> discover(DiscoveryQuery query, {int? since}) =>
const Stream.empty();
@override
Future<OfferPage> discoverPage(DiscoveryQuery query) async {
final matched = _byCreatedAt
.where((e) => e.offer.approxGeohash.startsWith(query.geohashPrefix))
.where((e) => query.until == null || e.createdAt <= query.until!)
.toList()
..sort((a, b) => b.createdAt.compareTo(a.createdAt));
final page = matched.take(query.limit).toList();
final nextCursor = page.length >= query.limit && page.isNotEmpty
? page.last.createdAt - 1
: null;
return OfferPage(
offers: [for (final e in page) e.offer],
nextCursor: nextCursor,
);
}
@override
Future<PublishResult> publish(Offer offer) async =>
PublishResult(accepted: true, transportRef: offer.id);
@override
Future<void> retract(String offerId) async {}
@override
Future<void> close() async {}
}
void main() {
group('OfferMapper', () {
test('maps local sharing intent to the network offer type', () {
expect(OfferMapper.offerTypeFor(OfferStatus.shared), OfferType.gift);
expect(OfferMapper.offerTypeFor(OfferStatus.exchange), OfferType.exchange);
expect(OfferMapper.offerTypeFor(OfferStatus.sell), OfferType.sale);
});
test('never publishes a private lot', () {
expect(() => OfferMapper.offerTypeFor(OfferStatus.private),
throwsArgumentError);
});
test('builds an offer, keeping price only for a sale', () {
final gift = OfferMapper.fromSharedLot(
lotId: 'lot-1',
authorPubkeyHex: 'ab' * 32,
summary: 'Tomate rosa',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
priceAmount: 5, // should be dropped for a gift
);
expect(gift.type, OfferType.gift);
expect(gift.id, 'lot-1');
expect(gift.priceAmount, isNull);
final sale = OfferMapper.fromSharedLot(
lotId: 'lot-2',
authorPubkeyHex: 'ab' * 32,
summary: 'Judía',
sharing: OfferStatus.sell,
areaGeohash: 'sp3e9',
priceAmount: 3,
priceCurrency: 'G1',
);
expect(sale.type, OfferType.sale);
expect(sale.priceAmount, 3);
expect(sale.priceCurrency, 'G1');
});
test('carries the organic (eco) flag through to the offer', () {
final eco = OfferMapper.fromSharedLot(
lotId: 'lot-1',
authorPubkeyHex: 'ab' * 32,
summary: 'Lechuga',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
isOrganic: true,
);
expect(eco.isOrganic, isTrue);
final plain = OfferMapper.fromSharedLot(
lotId: 'lot-2',
authorPubkeyHex: 'ab' * 32,
summary: 'Lechuga',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
);
expect(plain.isOrganic, isFalse);
});
});
group('OffersCubit', () {
test('discovers published offers by geohash prefix', () async {
final transport = FakeOfferTransport();
await transport.publish(OfferMapper.fromSharedLot(
lotId: 'lot-1',
authorPubkeyHex: 'ab' * 32,
summary: 'Tomate rosa de Barbastro',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
final cubit = OffersCubit(transport);
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.hasSearched, isTrue);
expect(cubit.state.searching, isFalse);
expect(cubit.state.offers, hasLength(1));
expect(cubit.state.offers.single.summary, 'Tomate rosa de Barbastro');
await cubit.close();
});
test('search narrows visible offers by summary, keeping the full list',
() async {
final transport = FakeOfferTransport();
for (final s in ['Tomate rosa', 'Judía verde', 'Tomate rojo']) {
await transport.publish(OfferMapper.fromSharedLot(
lotId: s,
authorPubkeyHex: 'ab' * 32,
summary: s,
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
}
final cubit = OffersCubit(transport);
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.offers, hasLength(3));
cubit.search('tomate'); // case-insensitive
expect(cubit.state.visibleOffers.map((o) => o.summary),
containsAll(['Tomate rosa', 'Tomate rojo']));
expect(cubit.state.visibleOffers, hasLength(2));
expect(cubit.state.offers, hasLength(3)); // underlying list untouched
cubit.search(''); // clearing shows everything again
expect(cubit.state.visibleOffers, hasLength(3));
await cubit.close();
});
test('blocked authors disappear from the visible list and can resurface',
() async {
final transport = FakeOfferTransport();
await transport.publish(OfferMapper.fromSharedLot(
lotId: 'lot-good',
authorPubkeyHex: 'ab' * 32,
summary: 'Tomate rosa',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
await transport.publish(OfferMapper.fromSharedLot(
lotId: 'lot-spam',
authorPubkeyHex: 'cd' * 32,
summary: 'Spam total',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
final cubit = OffersCubit(transport);
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.visibleOffers, hasLength(2));
cubit.setBlockedAuthors({'cd' * 32});
expect(cubit.state.visibleOffers.map((o) => o.summary), ['Tomate rosa']);
expect(cubit.state.offers, hasLength(2)); // discoveries kept underneath
// The blocklist survives a refresh (re-discovery resets results only).
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.visibleOffers.map((o) => o.summary), ['Tomate rosa']);
cubit.setBlockedAuthors(const {}); // unblock resurfaces
expect(cubit.state.visibleOffers, hasLength(2));
await cubit.close();
});
test('a hidden (reported) offer disappears without touching its author',
() async {
final transport = FakeOfferTransport();
for (final id in ['lot-1', 'lot-2']) {
await transport.publish(OfferMapper.fromSharedLot(
lotId: id,
authorPubkeyHex: 'ab' * 32,
summary: 'Oferta $id',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
}
final cubit = OffersCubit(transport);
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.visibleOffers, hasLength(2));
cubit.setHiddenOffers({'${'ab' * 32}:lot-1'});
expect(cubit.state.visibleOffers.map((o) => o.id), ['lot-2']);
await cubit.close();
});
test('the search filter survives a refresh (re-discovery)', () async {
final transport = FakeOfferTransport();
await transport.publish(OfferMapper.fromSharedLot(
lotId: 'lot-1',
authorPubkeyHex: 'ab' * 32,
summary: 'Pimiento',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
final cubit = OffersCubit(transport);
await cubit.discover('sp3');
await pumpEventQueue();
cubit.search('pim');
expect(cubit.state.query, 'pim');
await cubit.discover('sp3'); // pull-to-refresh
await pumpEventQueue();
expect(cubit.state.query, 'pim'); // kept across the refresh
expect(cubit.state.visibleOffers, hasLength(1));
await cubit.close();
});
test('a neighbour in an adjacent cell is found via the coarsened prefix',
() async {
// Regression: A publishes at 'sp3e9', B lives one ±2.4 km cell over at
// 'sp3e8'. Searching B's full 5-char area misses it; searching the
// precision-4 prefix ('sp3e') finds it, because publish emits the ladder.
final transport = FakeOfferTransport();
await transport.publish(OfferMapper.fromSharedLot(
lotId: 'lot-1',
authorPubkeyHex: 'ab' * 32,
summary: 'Tomate rosa',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
final cubit = OffersCubit(transport);
await cubit.discover(searchPrefix('sp3e8', 4)); // 'sp3e'
await pumpEventQueue();
expect(cubit.state.offers, hasLength(1));
await cubit.discover('sp3e8'); // full precision → the old, broken behaviour
await pumpEventQueue();
expect(cubit.state.offers, isEmpty);
await cubit.close();
});
test('a different area finds nothing', () async {
final transport = FakeOfferTransport();
await transport.publish(OfferMapper.fromSharedLot(
lotId: 'lot-1',
authorPubkeyHex: 'ab' * 32,
summary: 'Pimiento',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
final cubit = OffersCubit(transport);
await cubit.discover('u09');
await pumpEventQueue();
expect(cubit.state.offers, isEmpty);
await cubit.close();
});
test('publish reports the transport verdict', () async {
final cubit = OffersCubit(FakeOfferTransport());
final result = await cubit.publish(OfferMapper.fromSharedLot(
lotId: 'lot-9',
authorPubkeyHex: 'ab' * 32,
summary: 'Calabaza',
sharing: OfferStatus.exchange,
areaGeohash: 'sp3e9',
exchangeTerms: 'a cambio de legumbre',
));
expect(result.accepted, isTrue);
expect(cubit.state.publishing, isFalse);
await cubit.close();
});
test('publishLots publishes each shared lot and counts acceptances',
() async {
final transport = FakeOfferTransport();
final cubit = OffersCubit(transport);
final count = await cubit.publishLots(
const [
ShareableLot(
lotId: 'lot-1',
varietyId: 'var-1',
summary: 'Tomate',
offerStatus: OfferStatus.shared,
category: 'Solanaceae',
),
ShareableLot(
lotId: 'lot-2',
varietyId: 'var-2',
summary: 'Judía',
offerStatus: OfferStatus.exchange,
),
],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
);
expect(count, 2);
expect(cubit.state.publishing, isFalse);
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.offers, hasLength(2));
await cubit.close();
});
test('publishLots carries the lot asking price on sale offers', () async {
final transport = FakeOfferTransport();
final cubit = OffersCubit(transport);
await cubit.publishLots(
const [
ShareableLot(
lotId: 'lot-sale',
varietyId: 'var-1',
summary: 'Tomate',
offerStatus: OfferStatus.sell,
priceAmount: 3.5,
priceCurrency: 'Ğ1',
),
// "To be agreed": sale without a figure publishes without a price.
ShareableLot(
lotId: 'lot-negotiable',
varietyId: 'var-2',
summary: 'Judía',
offerStatus: OfferStatus.sell,
),
],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
);
await cubit.discover('sp3');
await pumpEventQueue();
final sale = cubit.state.offers.singleWhere((o) => o.id == 'lot-sale');
expect(sale.type, OfferType.sale);
expect(sale.priceAmount, 3.5);
expect(sale.priceCurrency, 'Ğ1');
final negotiable =
cubit.state.offers.singleWhere((o) => o.id == 'lot-negotiable');
expect(negotiable.priceAmount, isNull);
await cubit.close();
});
test('publishLots embeds an inline thumbnail data-URI on the offer',
() async {
final transport = FakeOfferTransport();
var thumbnailed = 0;
final cubit = OffersCubit(
transport,
coverPhoto: (id) async => Uint8List.fromList([1, 2, 3]),
thumbnail: (bytes) {
thumbnailed++;
return 'data:image/jpeg;base64,AAAA';
},
);
await cubit.publishLots(
const [
ShareableLot(
lotId: 'lot-1',
varietyId: 'var-1',
summary: 'Tomate',
offerStatus: OfferStatus.shared,
),
],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
);
await cubit.discover('sp3');
await pumpEventQueue();
expect(thumbnailed, 1);
expect(cubit.state.offers.single.imageUrl, 'data:image/jpeg;base64,AAAA');
await cubit.close();
});
test('publishLots still publishes (without image) when thumbnailing fails',
() async {
final transport = FakeOfferTransport();
final cubit = OffersCubit(
transport,
coverPhoto: (id) async => Uint8List.fromList([1, 2, 3]),
thumbnail: (bytes) => throw Exception('boom'),
);
final count = await cubit.publishLots(
const [
ShareableLot(
lotId: 'lot-1',
varietyId: 'var-1',
summary: 'Tomate',
offerStatus: OfferStatus.shared,
),
],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
);
expect(count, 1); // the offer still went out
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.offers.single.imageUrl, isNull);
await cubit.close();
});
test('publishLots without a thumbnailer publishes no image', () async {
final transport = FakeOfferTransport();
final cubit = OffersCubit(transport); // no thumbnail, no coverPhoto
await cubit.publishLots(
const [
ShareableLot(
lotId: 'lot-1',
varietyId: 'var-1',
summary: 'Tomate',
offerStatus: OfferStatus.shared,
),
],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
);
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.offers.single.imageUrl, isNull);
await cubit.close();
});
test('publishLots is a no-op offline or with no area', () async {
final offline = OffersCubit(null);
expect(
await offline.publishLots(
const [
ShareableLot(
lotId: 'x',
varietyId: 'vx',
summary: 'x',
offerStatus: OfferStatus.shared,
),
],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
),
0,
);
await offline.close();
final noArea = OffersCubit(FakeOfferTransport());
expect(
await noArea.publishLots(
const [
ShareableLot(
lotId: 'x',
varietyId: 'vx',
summary: 'x',
offerStatus: OfferStatus.shared,
),
],
authorPubkeyHex: 'ab' * 32,
areaGeohash: '',
),
0,
);
await noArea.close();
});
test('flushOutbox publishes queued lots, then clears them', () async {
final outbox = OfferOutbox(InMemorySecretStore());
await outbox.enqueue(['lot-1', 'lot-2']);
final cubit = OffersCubit(FakeOfferTransport());
final count = await flushOutbox(
outbox: outbox,
cubit: cubit,
shareableLots: const [
ShareableLot(
lotId: 'lot-1',
varietyId: 'var-1',
summary: 'Tomate',
offerStatus: OfferStatus.shared),
ShareableLot(
lotId: 'lot-2',
varietyId: 'var-2',
summary: 'Judía',
offerStatus: OfferStatus.exchange),
ShareableLot(
lotId: 'lot-3',
varietyId: 'var-3',
summary: 'Otro',
offerStatus: OfferStatus.shared),
],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
);
expect(count, 2);
expect(await outbox.pending(), isEmpty);
await cubit.close();
});
test('flushOutbox offline keeps the queue for later', () async {
final outbox = OfferOutbox(InMemorySecretStore());
await outbox.enqueue(['lot-1']);
final cubit = OffersCubit(null); // offline
final count = await flushOutbox(
outbox: outbox,
cubit: cubit,
shareableLots: const [],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
);
expect(count, 0);
expect(await outbox.pending(), {'lot-1'});
await cubit.close();
});
test('flushOutbox drops queued lots that no longer exist', () async {
final outbox = OfferOutbox(InMemorySecretStore());
await outbox.enqueue(['gone']);
final cubit = OffersCubit(FakeOfferTransport());
final count = await flushOutbox(
outbox: outbox,
cubit: cubit,
shareableLots: const [],
authorPubkeyHex: 'ab' * 32,
areaGeohash: 'sp3e9',
);
expect(count, 0);
expect(await outbox.pending(), isEmpty);
await cubit.close();
});
test('offline (no transport): degrades gracefully, never throws', () async {
final cubit = OffersCubit(null);
expect(cubit.isOnline, isFalse);
await cubit.discover('sp3');
expect(cubit.state.error, 'offline');
final result = await cubit.publish(OfferMapper.fromSharedLot(
lotId: 'x',
authorPubkeyHex: 'ab' * 32,
summary: 'x',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
expect(result.accepted, isFalse);
await cubit.close();
});
test('a resent offer is not duplicated in the list', () async {
// Regression: publishing an inventory lot showed up twice because the
// relay resends the addressable event; the cubit must dedup by author+id.
final transport = DuplicatingOfferTransport();
await transport.publish(OfferMapper.fromSharedLot(
lotId: 'lot-1',
authorPubkeyHex: 'ab' * 32,
summary: 'Tomate rosa',
sharing: OfferStatus.shared,
areaGeohash: 'sp3e9',
));
final cubit = OffersCubit(transport);
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.offers, hasLength(1));
await cubit.close();
});
test('two authors reusing the same lot id are kept apart', () async {
// A non-deduping transport, so both authors' same-id offers reach discover.
final transport = DuplicatingOfferTransport();
for (final author in ['ab' * 32, 'cd' * 32]) {
await transport.publish(Offer(
id: 'lot-1', // same d-tag, different author
authorPubkeyHex: author,
summary: 'Tomate',
type: OfferType.gift,
approxGeohash: 'sp3e9',
));
}
final cubit = OffersCubit(transport);
await cubit.discover('sp3');
await pumpEventQueue();
expect(cubit.state.offers, hasLength(2));
await cubit.close();
});
});
group('OffersCubit filters', () {
Offer offer(String id, OfferType type,
{String? category, bool organic = false}) =>
Offer(
id: id,
authorPubkeyHex: 'ab' * 32,
summary: id,
type: type,
category: category,
approxGeohash: 'sp3e9',
isOrganic: organic,
);
Future<OffersCubit> seeded(List<Offer> offers) async {
final transport = FakeOfferTransport();
for (final o in offers) {
await transport.publish(o);
}
final cubit = OffersCubit(transport);
await cubit.discover('sp3');
await pumpEventQueue();
return cubit;
}
test('type, category and eco chips narrow the list (ANDed with search)',
() async {
final cubit = await seeded([
offer('tomate-eco', OfferType.gift, category: 'Solanaceae', organic: true),
offer('tomate-sale', OfferType.sale, category: 'Solanaceae'),
offer('judia-eco', OfferType.gift, category: 'Fabaceae', organic: true),
]);
cubit.toggleType(OfferType.gift);
expect(cubit.state.visibleOffers.map((o) => o.id),
containsAll(['tomate-eco', 'judia-eco']));
expect(cubit.state.visibleOffers, hasLength(2));
cubit.toggleCategory('Solanaceae');
expect(cubit.state.visibleOffers.single.id, 'tomate-eco');
cubit.toggleOrganicOnly();
expect(cubit.state.visibleOffers.single.id, 'tomate-eco');
cubit.clearFilters();
expect(cubit.state.visibleOffers, hasLength(3));
expect(cubit.state.hasActiveFilter, isFalse);
await cubit.close();
});
test('exposes categories and hasOrganic from the discovered offers',
() async {
final cubit = await seeded([
offer('a', OfferType.gift, category: 'Solanaceae', organic: true),
offer('b', OfferType.gift, category: 'Fabaceae'),
offer('c', OfferType.gift),
]);
expect(cubit.state.categories, ['Fabaceae', 'Solanaceae']); // sorted
expect(cubit.state.hasOrganic, isTrue);
await cubit.close();
});
test('chip filters survive a refresh (re-discovery)', () async {
final cubit = await seeded([
offer('gift', OfferType.gift),
offer('sale', OfferType.sale),
]);
cubit.toggleType(OfferType.gift);
await cubit.discover('sp3'); // pull-to-refresh
await pumpEventQueue();
expect(cubit.state.typeFilter, {OfferType.gift});
expect(cubit.state.visibleOffers.single.id, 'gift');
await cubit.close();
});
});
group('OffersCubit pagination', () {
test('discover loads the first page and exposes a next-page cursor',
() async {
final cubit = OffersCubit(PaginatingOfferTransport(250));
await cubit.discover('sp3');
await pumpEventQueue();
// One page (default limit 100) — not the whole 250 — is kept in memory.
expect(cubit.state.offers, hasLength(100));
expect(cubit.state.canLoadMore, isTrue);
expect(cubit.state.searching, isFalse);
await cubit.close();
});
test('loadNextPage accumulates older offers until the source is exhausted',
() async {
final cubit = OffersCubit(PaginatingOfferTransport(250));
await cubit.discover('sp3');
await pumpEventQueue();
await cubit.loadNextPage();
expect(cubit.state.offers, hasLength(200));
expect(cubit.state.canLoadMore, isTrue);
await cubit.loadNextPage();
// Only 250 exist: the third page is short, so there is nothing older.
expect(cubit.state.offers, hasLength(250));
expect(cubit.state.canLoadMore, isFalse);
// Paging past the end is a harmless no-op.
await cubit.loadNextPage();
expect(cubit.state.offers, hasLength(250));
await cubit.close();
});
test('the in-memory list is capped and paging stops at the cap', () async {
final cubit = OffersCubit(PaginatingOfferTransport(600));
await cubit.discover('sp3');
await pumpEventQueue();
// Keep paging until the cubit says there is no more.
var guard = 0;
while (cubit.state.canLoadMore && guard++ < 20) {
await cubit.loadNextPage();
}
expect(cubit.state.offers, hasLength(OffersCubit.maxOffersKept));
expect(cubit.state.canLoadMore, isFalse);
await cubit.close();
});
test('offers are de-duplicated across pages by (author, id)', () async {
// Two pages that overlap on the boundary id must not double it.
final cubit = OffersCubit(PaginatingOfferTransport(150));
await cubit.discover('sp3');
await pumpEventQueue();
await cubit.loadNextPage();
final ids = cubit.state.offers.map((o) => o.id).toList();
expect(ids.toSet(), hasLength(ids.length)); // no duplicates
expect(cubit.state.offers, hasLength(150));
await cubit.close();
});
});
}