add

app/test/search_history_store_test.dart

@@ -0,0 +1,57 @@
+// 搜索历史本地存储单测：去重置顶 / 上限 10 条 / 删除 / 清空
+import 'package:flutter_test/flutter_test.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import 'package:video_app/core/storage/search_history_store.dart';
+
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  Future<SearchHistoryStore> setup([Map<String, Object> initial = const {}]) async {
+    SharedPreferences.setMockInitialValues(initial);
+    final prefs = await SharedPreferences.getInstance();
+    SearchHistoryStore.initForTest(prefs);
+    return SearchHistoryStore.I;
+  }
+
+  test('add 追加并最新在前', () async {
+    final store = await setup();
+    await store.add('日落');
+    await store.add('美食');
+    expect(store.history, ['美食', '日落']);
+  });
+
+  test('重复关键词去重置顶', () async {
+    final store = await setup();
+    await store.add('日落');
+    await store.add('美食');
+    await store.add('日落');
+    expect(store.history, ['日落', '美食']);
+  });
+
+  test('超出 10 条截断最旧记录', () async {
+    final store = await setup();
+    for (var i = 1; i <= 12; i++) {
+      await store.add('词$i');
+    }
+    expect(store.history, hasLength(10));
+    expect(store.history.first, '词12');
+    expect(store.history.last, '词3');
+  });
+
+  test('空白关键词不入库', () async {
+    final store = await setup();
+    await store.add('   ');
+    expect(store.history, isEmpty);
+  });
+
+  test('remove 删除单条，clear 清空', () async {
+    final store = await setup();
+    await store.add('日落');
+    await store.add('美食');
+    await store.remove('日落');
+    expect(store.history, ['美食']);
+    await store.clear();
+    expect(store.history, isEmpty);
+  });
+}