fix(database): repair legacy profile labels

lib/database/database.dart

@@ -33,7 +33,7 @@ class Database extends _$Database {
   Database([QueryExecutor? executor]) : super(executor ?? _openConnection());
 
   @override
-  int get schemaVersion => 2;
+  int get schemaVersion => 3;
 
   static LazyDatabase _openConnection() {
     return LazyDatabase(() async {
@@ -52,6 +52,9 @@ class Database extends _$Database {
           await _resetOrders();
           await _migrateRules(m);
         }
+        if (from < 3) {
+          await _repairLegacyProfileLabels();
+        }
       },
       beforeOpen: (details) async {
         // final m = Migrator(this);
@@ -114,6 +117,12 @@ class Database extends _$Database {
     await rulesDao.resetOrders();
   }
 
+  Future<void> _repairLegacyProfileLabels() {
+    return customStatement(
+      "UPDATE profiles SET label = '' WHERE label IS NULL",
+    );
+  }
+
   Future<void> restore(
     List<Profile> profiles,
     List<Script> scripts,

test/database/database_test.dart

@@ -0,0 +1,55 @@
+import 'dart:io';
+
+import 'package:drift/native.dart';
+import 'package:fl_clash/database/database.dart';
+import 'package:sqlite3/sqlite3.dart' as sqlite;
+import 'package:test/test.dart';
+
+void main() {
+  test(
+    'repairs legacy profiles with a missing label before reading them',
+    () async {
+      final directory = await Directory.systemTemp.createTemp(
+        'flclash-db-test-',
+      );
+      final file = File('${directory.path}/data.sqlite');
+      final legacyDatabase = sqlite.sqlite3.open(file.path);
+      addTearDown(() async {
+        await directory.delete(recursive: true);
+      });
+
+      legacyDatabase.execute('''
+      CREATE TABLE profiles (
+        id INTEGER NOT NULL PRIMARY KEY,
+        label TEXT,
+        current_group_name TEXT,
+        url TEXT NOT NULL,
+        last_update_date INTEGER,
+        overwrite_type TEXT NOT NULL,
+        script_id INTEGER,
+        auto_update_duration_millis INTEGER NOT NULL,
+        subscription_info TEXT,
+        auto_update INTEGER NOT NULL,
+        selected_map TEXT NOT NULL,
+        unfold_set TEXT NOT NULL,
+        "order" INTEGER
+      );
+    ''');
+      legacyDatabase.execute('''
+      INSERT INTO profiles (
+        id, label, url, overwrite_type, auto_update_duration_millis,
+        auto_update, selected_map, unfold_set
+      ) VALUES (1, NULL, '', 'standard', 0, 0, '{}', '[]');
+    ''');
+      legacyDatabase.execute('PRAGMA user_version = 2;');
+      legacyDatabase.dispose();
+
+      final database = Database(NativeDatabase(file));
+      addTearDown(database.close);
+
+      final profiles = await database.profilesDao.query().get();
+
+      expect(profiles.single.label, isEmpty);
+    },
+  );
+}