Properly close read/write lock context.

Author: rkistner

lib/src/sqlite_connection_impl.dart

@@ -142,7 +142,7 @@ class _TransactionContext implements SqliteWriteContext {
   Future<sqlite.ResultSet> getAll(String sql,
       [List<Object?> parameters = const []]) async {
     if (_closed) {
-      throw AssertionError('Transaction closed');
+      throw sqlite.SqliteException(0, 'Transaction closed', null, sql);
     }
     try {
       var future = _sendPort.post<sqlite.ResultSet>(
@@ -183,8 +183,9 @@ class _TransactionContext implements SqliteWriteContext {
     return rows.isEmpty ? null : rows[0];
   }
 
-  close() {
+  Future<void> close() async {
     _closed = true;
+    await _sendPort.post(_SqliteIsolateClose(ctxId));
   }
 
   @override
@@ -234,8 +235,8 @@ void _sqliteConnectionIsolate(_SqliteConnectionParams params) async {
         }
         txId = null;
         txError = null;
-        throw AssertionError(
-            'Transaction must be closed within the read or write lock');
+        throw sqlite.SqliteException(
+            0, 'Transaction must be closed within the read or write lock');
       }
     } else if (data is _SqliteIsolateStatement) {
       if (data.sql == 'BEGIN' || data.sql == 'BEGIN IMMEDIATE') {
@@ -254,7 +255,7 @@ void _sqliteConnectionIsolate(_SqliteConnectionParams params) async {
         // Any statement (including COMMIT) after the first error will also error, until the
         // transaction is aborted.
         throw txError!;
-      } else if (data.sql == 'COMMIT') {
+      } else if (data.sql == 'COMMIT' || data.sql == 'END TRANSACTION') {
         txId = null;
       }
       try {

test/basic_test.dart

@@ -191,6 +191,14 @@ void main() {
       // Check that we can open another transaction afterwards
       await db.writeTransaction((tx) async {});
     });
+
+    test('should error on dangling transactions', () async {
+      final db = await setupDatabase(path: path);
+      await createTables(db);
+      await expectLater(() async {
+        await db.execute('BEGIN');
+      }, throwsA((e) => e is sqlite.SqliteException));
+    });
   });
 }