From d14e3909d4fd46c84c28af6580398b422d2dc1d1 Mon Sep 17 00:00:00 2001
From: h7x4 <h7x4@nani.wtf>
Date: Mon, 2 Mar 2026 17:37:45 +0900
Subject: [PATCH] search/filter_kanji: keep order when deduplicating

---
 lib/search/filter_kanji.dart       | 10 +++++++++-
 test/search/filter_kanji_test.dart | 23 +++++++++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/lib/search/filter_kanji.dart b/lib/search/filter_kanji.dart
index 4a00dce..95a0db8 100644
--- a/lib/search/filter_kanji.dart
+++ b/lib/search/filter_kanji.dart
@@ -18,7 +18,15 @@ Future<List<String>> filterKanjiWithDbConnection(
       .then((value) => value.map((e) => e['literal'] as String).toSet());
 
   if (deduplicate) {
-    return filteredKanji.toList();
+    final List<String> result = [];
+    final Set<String> seen = {};
+    for (final k in kanji) {
+      if (filteredKanji.contains(k) && !seen.contains(k)) {
+        result.add(k);
+        seen.add(k);
+      }
+    }
+    return result;
   } else {
     return kanji.where((k) => filteredKanji.contains(k)).toList();
   }
diff --git a/test/search/filter_kanji_test.dart b/test/search/filter_kanji_test.dart
index ef7d96c..ecc2e25 100644
--- a/test/search/filter_kanji_test.dart
+++ b/test/search/filter_kanji_test.dart
@@ -26,4 +26,27 @@ void main() {
 
     expect(result.join(), '漢字地字');
   });
+
+  test('Filter kanji - deduplicate', () async {
+    final connection = await setupDatabaseConnection();
+
+    final result = await connection.filterKanji([
+      'a',
+      'b',
+      'c',
+      '漢',
+      '字',
+      '地',
+      '字',
+      'か',
+      'な',
+      '.',
+      '!',
+      '@',
+      ';',
+      '々',
+    ], deduplicate: true);
+
+    expect(result.join(), '漢字地');
+  });
 }