Test for issue#398 (#399)

test/event_after_closing_test.dart

@@ -0,0 +1,82 @@
+import 'dart:async';
+
+import 'package:postgres/postgres.dart';
+import 'package:test/test.dart';
+
+import 'docker.dart';
+
+void _print(x) {
+  // uncomment to debug locally
+  // print(x);
+}
+
+void main() {
+  withPostgresServer('event after closing', (server) {
+    Future<void> createTableAndPopulate(Connection conn) async {
+      final sw = Stopwatch()..start();
+
+      await conn.execute('''
+    CREATE TABLE IF NOT EXISTS large_table (
+      id SERIAL PRIMARY KEY,
+      c1 INTEGER NOT NULL,
+      c2 INTEGER NOT NULL,
+      c3 TEXT NOT NULL,
+      c4 TEXT NOT NULL,
+      c5 TEXT NOT NULL,
+      c6 TEXT NOT NULL,
+      c7 TEXT NOT NULL,
+      c8 TEXT NOT NULL,
+      c9 TEXT NOT NULL,
+      c10 TEXT NOT NULL
+    )
+  ''');
+
+      final numBatches = 20;
+      final batchSize = 5000;
+
+      for (var i = 0; i < numBatches; i++) {
+        _print('Batch $i of $numBatches');
+        final values = List.generate(
+            batchSize,
+            (i) => [
+                  i,
+                  i * 2,
+                  'value $i',
+                  'value $i',
+                  'value $i',
+                  'value $i',
+                  'value $i',
+                  'value $i',
+                  'value $i',
+                  'value $i',
+                ]);
+
+        final allArgs = values.expand((e) => e).toList();
+        final valuesPart = List.generate(
+                batchSize,
+                (i) =>
+                    '(${List.generate(10, (j) => '\$${i * 10 + j + 1}').join(', ')})')
+            .join(', ');
+
+        final stmt =
+            'INSERT INTO large_table (c1, c2, c3, c4, c5, c6, c7, c8, c9, c10) VALUES $valuesPart';
+        await conn.execute(
+          stmt,
+          parameters: allArgs,
+        );
+      }
+
+      _print('Inserted ${numBatches * batchSize} rows in ${sw.elapsed}');
+    }
+
+    test('issue#398', () async {
+      final conn = await server.newConnection();
+      await createTableAndPopulate(conn);
+
+      final rows = await conn.execute('SELECT * FROM large_table');
+      _print('SELECTED ROWS ${rows.length}');
+
+      await conn.close();
+    });
+  });
+}