[red] expose stale editor board operations across revisions and sessions

Signed-off-by: Viwat Vchirawongkwin <viwat.v@chula.ac.th>

Author: yyods

app/test/unit/recovery_board_races_test.dart

@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: MIT
+// Part of PyBLE (https://pyble.dev) — see /LICENSE.
+
+import 'dart:async';
+import 'dart:convert';
+import 'dart:typed_data';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:pyble/app/providers.dart';
+import 'package:pyble/editor/editor.dart';
+import 'package:pyble/files/files.dart';
+import 'package:pyble/pble/pble.dart';
+import '../support/recording_connection.dart';
+
+class HeldConnection extends RecordingConnection
+    implements ConnectionSessionStampSource {
+  HeldConnection() : super(initial: ConnState.ready);
+  Object stamp = Object();
+  @override
+  Object get connectionSessionStamp => stamp;
+  final entered = Completer<void>();
+  final release = Completer<void>();
+  bool holdPut = true;
+  bool holdGet = false;
+  @override
+  Future<void> putFile(
+    String path,
+    Uint8List bytes, {
+    ProgressCb? onProgress,
+  }) async {
+    await super.putFile(path, bytes, onProgress: onProgress);
+    if (holdPut) {
+      if (!entered.isCompleted) entered.complete();
+      await release.future;
+    }
+  }
+
+  @override
+  Future<Uint8List> getFile(String path, {ProgressCb? onProgress}) async {
+    final result = await super.getFile(path, onProgress: onProgress);
+    if (holdGet) {
+      if (!entered.isCompleted) entered.complete();
+      await release.future;
+    }
+    return result;
+  }
+}
+
+void main() {
+  ProviderContainer bind(HeldConnection connection) {
+    final c = ProviderContainer(
+      overrides: [connectionProvider.overrideWithValue(connection)],
+    );
+    addTearDown(c.dispose);
+    addTearDown(() {
+      if (!connection.release.isCompleted) connection.release.complete();
+    });
+    return c;
+  }
+
+  test('Save completion cannot clear an edit-away/back revision', () async {
+    final connection = HeldConnection();
+    final c = bind(connection);
+    final doc = c.read(editorDocumentProvider.notifier)..setContent('original');
+    final save = c.read(saveControllerProvider).save();
+    await connection.entered.future;
+    doc.setContent('newer');
+    doc.setContent('original');
+    connection.release.complete();
+    await save;
+    expect(c.read(editorDocumentProvider).dirty, isTrue);
+    expect(c.read(editorDocumentProvider).boardPath, isNull);
+  });
+  test('Run never dispatches second verb on a replaced attachment', () async {
+    final connection = HeldConnection();
+    final c = bind(connection);
+    c.read(editorDocumentProvider.notifier).setContent('print(1)');
+    final run = c.read(runControllerProvider).run();
+    final result = expectLater(run, throwsA(isA<Exception>()));
+    await connection.entered.future;
+    connection.stamp = Object();
+    connection.release.complete();
+    await result;
+    expect(connection.runFileCalls, isEmpty);
+    expect(c.read(editorDocumentProvider).dirty, isTrue);
+  });
+  test(
+    'Board Open refuses old GET after stable facade changes attachment',
+    () async {
+      final connection = HeldConnection()..holdPut = false;
+      await connection.putFile(
+        '/board.py',
+        Uint8List.fromList(utf8.encode('old board')),
+      );
+      connection.holdGet = true;
+      final c = bind(connection);
+      final files = c.read(fileExplorerProvider.notifier);
+      await pumpEventQueue();
+      final open = files.openInEditor('board.py');
+      await connection.entered.future;
+      connection.stamp = Object();
+      connection.release.complete();
+      await open;
+      expect(c.read(editorDocumentProvider).content, isEmpty);
+      expect(c.read(editorDocumentProvider).boardPath, isNull);
+    },
+  );
+  test(
+    'Files upload completion cannot bind an edit-away/back revision',
+    () async {
+      final connection = HeldConnection();
+      final c = bind(connection);
+      final files = c.read(fileExplorerProvider.notifier);
+      await pumpEventQueue();
+      final doc = c.read(editorDocumentProvider.notifier)
+        ..setContent('original');
+      final upload = files.uploadCurrentBuffer();
+      await connection.entered.future;
+      doc.setContent('newer');
+      doc.setContent('original');
+      connection.release.complete();
+      await upload;
+      expect(c.read(editorDocumentProvider).dirty, isTrue);
+      expect(c.read(editorDocumentProvider).boardPath, isNull);
+    },
+  );
+}