Block database after error in migration

drift/CHANGELOG.md

@@ -1,3 +1,9 @@
+## 2.16.0-dev
+
+- When a migration throws, the database  will now block subsequent operations
+  instead of potentially allowing them to operate on a database in an
+  inconsistent state.
+
 ## 2.15.0
 
 - Methods in the query builder API now respect custom types.

drift/lib/src/runtime/executor/helpers/engines.dart

@@ -386,6 +386,7 @@ class _WrappingTransactionExecutor extends _TransactionExecutor {
 class DelegatedDatabase extends _BaseExecutor {
   /// The [DatabaseDelegate] to send queries to.
   final DatabaseDelegate delegate;
+  (Object, StackTrace)? _migrationError;
 
   @override
   bool logStatements;
@@ -415,6 +416,12 @@ class DelegatedDatabase extends _BaseExecutor {
             'database connection and open that instead.'));
       }
 
+      // If we have been unable to run migrations, the database is likely in an
+      // inconsistent state and we should prevent subsequent operations on it.
+      if (_migrationError case (var err, var trace)?) {
+        Error.throwWithStackTrace(err, trace);
+      }
+
       final alreadyOpen = await delegate.isOpen;
       if (alreadyOpen) {
         _ensureOpenCalled = true;
@@ -423,8 +430,14 @@ class DelegatedDatabase extends _BaseExecutor {
 
       await delegate.open(user);
       _ensureOpenCalled = true;
-      await _runMigrations(user);
-      return true;
+
+      try {
+        await _runMigrations(user);
+        return true;
+      } catch (e, s) {
+        _migrationError = (e, s);
+        rethrow;
+      }
     });
   }
 

drift/test/platforms/ffi/native_database_test.dart

@@ -231,6 +231,20 @@ void main() {
       )),
     );
   });
+
+  test('prevents database access after failed migrations', () async {
+    final db = TodoDb(NativeDatabase.memory());
+    final exception = 'exception';
+    db.migration = MigrationStrategy(onCreate: (_) async => throw exception);
+
+    await expectLater(db.customSelect('SELECT 1').get(), throwsA(exception));
+
+    // The database should now be unusable.
+    db.migration = MigrationStrategy();
+    await expectLater(db.customSelect('SELECT 1').get(), throwsA(exception));
+
+    await db.close();
+  });
 }
 
 class _FakeExecutorUser extends QueryExecutorUser {