feat(logger): add extensible logging API, usage examples, and bilingual documentation

- Introduce CherryPickLogger interface, PrintLogger and SilentLogger implementations
- Add setGlobalLogger() to CherryPick API for custom DI logging
- Log key events (scope, module, error) via logger throughout DI lifecycle
- Comprehensive comments and code documentation in both English and Russian
- Document usage of logging system in quick_start and full_tutorial documentation (EN/RU)
- Provide usage examples in docs and code comments
- No logging inside GlobalCycleDetectionMixin (design choice: exceptions handled at Scope, not detector/mixin level) and detailed architectural reasoning
- Update helper.dart, logger.dart: comments, examples, API doc improvements
BREAKING CHANGE: Projects can now inject any logger via CherryPick.setGlobalLogger; default log behavior clarified and docstrings/usage examples enhanced

cherrypick/README.md

@@ -234,6 +234,32 @@ class ApiClientImpl implements ApiClient {
 }
 ```
 
+## Logging
+
+CherryPick supports centralized logging of all dependency injection (DI) events and errors. You can globally enable logs for your application or test environment with:
+
+```dart
+import 'package:cherrypick/cherrypick.dart';
+
+void main() {
+  // Set a global logger before any scopes are created
+  CherryPick.setGlobalLogger(PrintLogger()); // or your custom logger
+
+  final scope = CherryPick.openRootScope();
+  // All DI actions and errors will now be logged!
+}
+```
+- All dependency resolution, scope creation, module installation, and circular dependency errors will be sent to your logger (via info/error method).
+- By default, logs are off (SilentLogger is used in production).
+
+If you want fine-grained, test-local, or isolated logging, you can provide a logger directly to each scope:
+
+```dart
+final logger = MockLogger();
+final scope = Scope(null, logger: logger); // works in tests for isolation
+scope.installModules([...]);
+```
+
 ## Features
 
 - [x] Main Scope and Named Subscopes

cherrypick/example/cherrypick_logger_demo.dart

@@ -0,0 +1,37 @@
+import 'package:cherrypick/cherrypick.dart';
+
+/// Example of a simple service class.
+class UserRepository {
+  String getUserName() => 'Sergey DI';
+}
+
+/// DI module for registering dependencies.
+class AppModule extends Module {
+  @override
+  void builder(Scope currentScope) {
+    bind<UserRepository>().toInstance(UserRepository());
+  }
+}
+
+void main() {
+  // Set a global logger for the DI system
+  CherryPick.setGlobalLogger(PrintLogger());
+
+  // Open the root scope
+  final rootScope = CherryPick.openRootScope();
+
+  // Register the DI module
+  rootScope.installModules([AppModule()]);
+
+  // Resolve a dependency (service)
+  final repo = rootScope.resolve<UserRepository>();
+  print('User: ${repo.getUserName()}');
+
+  // Work with a sub-scope (create/close)
+  final subScope = rootScope.openSubScope('feature.profile');
+  subScope.closeSubScope('feature.profile');
+
+  // Demonstrate disabling and re-enabling logging
+  CherryPick.setGlobalLogger(const SilentLogger());
+  rootScope.resolve<UserRepository>(); // now without logs
+}

cherrypick/lib/cherrypick.dart

@@ -20,3 +20,4 @@ export 'package:cherrypick/src/global_cycle_detector.dart';
 export 'package:cherrypick/src/helper.dart';
 export 'package:cherrypick/src/module.dart';
 export 'package:cherrypick/src/scope.dart';
+export 'package:cherrypick/src/logger.dart';

cherrypick/lib/src/binding.dart

@@ -16,14 +16,51 @@ import 'package:cherrypick/src/binding_resolver.dart';
 /// RU: Класс Binding<T> настраивает параметры экземпляра.
 /// ENG: The Binding<T> class configures the settings for the instance.
 ///
+import 'package:cherrypick/src/logger.dart';
+
 class Binding<T> {
   late Type _key;
   String? _name;
 
   BindingResolver<T>? _resolver;
 
-  Binding() {
+  CherryPickLogger? logger;
+
+  // Deferred logging flags
+  bool _createdLogged = false;
+  bool _namedLogged = false;
+  bool _singletonLogged = false;
+
+  Binding({this.logger}) {
     _key = T;
+    // Не логируем здесь! Делаем deferred лог после назначения logger
+  }
+
+  void markCreated() {
+    if (!_createdLogged) {
+      logger?.info('Binding<$T> created');
+      _createdLogged = true;
+    }
+  }
+
+  void markNamed() {
+    if (isNamed && !_namedLogged) {
+      logger?.info('Binding<$T> named as [$_name]');
+      _namedLogged = true;
+    }
+  }
+
+  void markSingleton() {
+    if (isSingleton && !_singletonLogged) {
+      logger?.info('Binding<$T> singleton mode enabled');
+      _singletonLogged = true;
+    }
+  }
+
+  void logAllDeferred() {
+    markCreated();
+    markNamed();
+    markSingleton();
   }
 
   /// RU: Метод возвращает тип экземпляра.
@@ -58,6 +95,7 @@ class Binding<T> {
   /// return [Binding]
   Binding<T> withName(String name) {
     _name = name;
+    // Не логируем здесь, deferred log via markNamed()
     return this;
   }
 
@@ -67,7 +105,6 @@ class Binding<T> {
   /// return [Binding]
   Binding<T> toInstance(Instance<T> value) {
     _resolver = InstanceResolver<T>(value);
-
     return this;
   }
 
@@ -77,7 +114,6 @@ class Binding<T> {
   /// return [Binding]
   Binding<T> toProvide(Provider<T> value) {
     _resolver = ProviderResolver<T>((_) => value.call(), withParams: false);
-
     return this;
   }
 
@@ -87,7 +123,6 @@ class Binding<T> {
   /// return [Binding]
   Binding<T> toProvideWithParams(ProviderWithParams<T> value) {
     _resolver = ProviderResolver<T>(value, withParams: true);
-
     return this;
   }
 
@@ -112,15 +147,28 @@ class Binding<T> {
   /// return [Binding]
   Binding<T> singleton() {
     _resolver?.toSingleton();
-
+    // Не логируем здесь, deferred log via markSingleton()
     return this;
   }
 
   T? resolveSync([dynamic params]) {
-    return resolver?.resolveSync(params);
+    final res = resolver?.resolveSync(params);
+    if (res != null) {
+      logger?.info('Binding<$T> resolveSync => object created/resolved.');
+    } else {
+      logger?.warn('Binding<$T> resolveSync => returned null!');
+    }
+    return res;
   }
 
   Future<T>? resolveAsync([dynamic params]) {
-    return resolver?.resolveAsync(params);
+    final future = resolver?.resolveAsync(params);
+    if (future != null) {
+      future.then((res) => logger?.info('Binding<$T> resolveAsync => Future resolved'))
+            .catchError((e, s) => logger?.error('Binding<$T> resolveAsync error', e, s));
+    } else {
+      logger?.warn('Binding<$T> resolveAsync => returned null!');
+    }
+    return future;
   }
 }

cherrypick/lib/src/cycle_detector.dart

@@ -12,6 +12,7 @@
 //
 
 import 'dart:collection';
+import 'package:cherrypick/src/logger.dart';
 
 /// RU: Исключение, выбрасываемое при обнаружении циклической зависимости.
 /// ENG: Exception thrown when a circular dependency is detected.
@@ -31,24 +32,30 @@ class CircularDependencyException implements Exception {
 /// RU: Детектор циклических зависимостей для CherryPick DI контейнера.
 /// ENG: Circular dependency detector for CherryPick DI container.
 class CycleDetector {
+  final CherryPickLogger logger;
   // Стек текущих разрешаемых зависимостей
   final Set<String> _resolutionStack = HashSet<String>();
   
   // История разрешения для построения цепочки зависимостей
   final List<String> _resolutionHistory = [];
 
+  CycleDetector({CherryPickLogger? logger}) : logger = logger ?? const SilentLogger() {
+    // print removed (trace)
+  }
+
   /// RU: Начинает отслеживание разрешения зависимости.
   /// ENG: Starts tracking dependency resolution.
   /// 
   /// Throws [CircularDependencyException] if circular dependency is detected.
   void startResolving<T>({String? named}) {
     final dependencyKey = _createDependencyKey<T>(named);
-    
+    logger.info('CycleDetector: startResolving $dependencyKey stackSize=${_resolutionStack.length}');
     if (_resolutionStack.contains(dependencyKey)) {
       // Найдена циклическая зависимость
       final cycleStartIndex = _resolutionHistory.indexOf(dependencyKey);
       final cycle = _resolutionHistory.sublist(cycleStartIndex)..add(dependencyKey);
-      
+      // print removed (trace)
+      logger.error('CycleDetector: CYCLE DETECTED! $dependencyKey chain: ${cycle.join(' -> ')}');
       throw CircularDependencyException(
         'Circular dependency detected for $dependencyKey',
         cycle,
@@ -63,8 +70,8 @@ class CycleDetector {
   /// ENG: Finishes tracking dependency resolution.
   void finishResolving<T>({String? named}) {
     final dependencyKey = _createDependencyKey<T>(named);
+    logger.info('CycleDetector: finishResolving $dependencyKey');
     _resolutionStack.remove(dependencyKey);
-    
     // Удаляем из истории только если это последний элемент
     if (_resolutionHistory.isNotEmpty && 
         _resolutionHistory.last == dependencyKey) {
@@ -75,6 +82,7 @@ class CycleDetector {
   /// RU: Очищает все состояние детектора.
   /// ENG: Clears all detector state.
   void clear() {
+    logger.info('CycleDetector: clear');
     _resolutionStack.clear();
     _resolutionHistory.clear();
   }
@@ -103,16 +111,21 @@ class CycleDetector {
 mixin CycleDetectionMixin {
   CycleDetector? _cycleDetector;
 
+  CherryPickLogger? get logger;
+
   /// RU: Включает обнаружение циклических зависимостей.
   /// ENG: Enables circular dependency detection.
   void enableCycleDetection() {
-    _cycleDetector = CycleDetector();
+    // print removed (trace)
+    _cycleDetector = CycleDetector(logger: logger);
+    logger?.info('CycleDetection: cycle detection enabled');
   }
 
   /// RU: Отключает обнаружение циклических зависимостей.
   /// ENG: Disables circular dependency detection.
   void disableCycleDetection() {
     _cycleDetector?.clear();
+    logger?.info('CycleDetection: cycle detection disabled');
     _cycleDetector = null;
   }
 

cherrypick/lib/src/helper.dart

@@ -12,30 +12,72 @@
 //
 import 'package:cherrypick/src/scope.dart';
 import 'package:cherrypick/src/global_cycle_detector.dart';
+import 'package:cherrypick/src/logger.dart';
 import 'package:meta/meta.dart';
 
+CherryPickLogger? _globalLogger = const SilentLogger();
+
 Scope? _rootScope;
 bool _globalCycleDetectionEnabled = false;
 bool _globalCrossScopeCycleDetectionEnabled = false;
 
 class CherryPick {
+  /// Позволяет задать глобальный логгер для всей DI-системы.
+  /// ----------------------------------------------------------------------------
+  /// setGlobalLogger — установка глобального логгера для всей системы CherryPick DI.
+  ///
+  /// ENGLISH:
+  /// Sets the global logger for all CherryPick DI containers and scopes.
+  /// All dependency resolution, scope lifecycle, and error events will use
+  /// this logger instance for info/warn/error output.
+  /// Can be used to connect a custom logger (e.g. to external monitoring or UI).
+  ///
+  /// Usage example:
+  /// ```dart
+  /// import 'package:cherrypick/cherrypick.dart';
+  ///
+  /// void main() {
+  ///   CherryPick.setGlobalLogger(PrintLogger()); // Or your custom logger
+  ///   final rootScope = CherryPick.openRootScope();
+  ///   // DI logs and errors will now go to your logger
+  /// }
+  /// ```
+  ///
+  /// RUSSIAN:
+  /// Устанавливает глобальный логгер для всей DI-системы CherryPick.
+  /// Все операции разрешения зависимостей, жизненного цикла скоупов и ошибки
+  /// будут регистрироваться через этот логгер (info/warn/error).
+  /// Можно подключить свою реализацию для интеграции со сторонними системами.
+  ///
+  /// Пример использования:
+  /// ```dart
+  /// import 'package:cherrypick/cherrypick.dart';
+  ///
+  /// void main() {
+  ///   CherryPick.setGlobalLogger(PrintLogger()); // Или ваш собственный логгер
+  ///   final rootScope = CherryPick.openRootScope();
+  ///   // Все события DI и ошибки попадут в ваш логгер.
+  /// }
+  /// ```
+  /// ----------------------------------------------------------------------------
+  static void setGlobalLogger(CherryPickLogger logger) {
+    _globalLogger = logger;
+  }
+
   /// RU: Метод открывает главный [Scope].
   /// ENG: The method opens the main [Scope].
   ///
   /// return
   static Scope openRootScope() {
-    _rootScope ??= Scope(null);
-    
+    _rootScope ??= Scope(null, logger: _globalLogger);
     // Применяем глобальную настройку обнаружения циклических зависимостей
     if (_globalCycleDetectionEnabled && !_rootScope!.isCycleDetectionEnabled) {
       _rootScope!.enableCycleDetection();
     }
-    
     // Применяем глобальную настройку обнаружения между скоупами
     if (_globalCrossScopeCycleDetectionEnabled && !_rootScope!.isGlobalCycleDetectionEnabled) {
       _rootScope!.enableGlobalCycleDetection();
     }
-    
     return _rootScope!;
   }
 

cherrypick/lib/src/logger.dart

@@ -0,0 +1,108 @@
+//
+// Copyright 2021 Sergey Penkovsky (sergey.penkovsky@gmail.com)
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//      http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+/// ----------------------------------------------------------------------------
+/// CherryPickLogger — интерфейс для логирования событий DI в CherryPick.
+///
+/// ENGLISH:
+/// Interface for dependency injection (DI) logger in CherryPick. Allows you to
+/// receive information about the internal events and errors in the DI system.
+/// Your implementation can use any logging framework or UI.
+///
+/// RUSSIAN:
+/// Интерфейс логгера для DI-контейнера CherryPick. Позволяет получать
+/// сообщения о работе DI-контейнера, его ошибках и событиях, и
+/// интегрировать любые готовые решения для логирования/сбора ошибок.
+/// ----------------------------------------------------------------------------
+abstract class CherryPickLogger {
+  /// ----------------------------------------------------------------------------
+  /// info — Информационное сообщение.
+  ///
+  /// ENGLISH:
+  /// Logs an informational message about DI operation or state.
+  ///
+  /// RUSSIAN:
+  /// Логирование информационного сообщения о событиях DI.
+  /// ----------------------------------------------------------------------------
+  void info(String message);
+
+  /// ----------------------------------------------------------------------------
+  /// warn — Предупреждение.
+  ///
+  /// ENGLISH:
+  /// Logs a warning related to DI events (for example, possible misconfiguration).
+  ///
+  /// RUSSIAN:
+  /// Логирование предупреждения, связанного с DI (например, возможная ошибка
+  /// конфигурации).
+  /// ----------------------------------------------------------------------------
+  void warn(String message);
+
+  /// ----------------------------------------------------------------------------
+  /// error — Ошибка.
+  ///
+  /// ENGLISH:
+  /// Logs an error message, may include error object and stack trace.
+  ///
+  /// RUSSIAN:
+  /// Логирование ошибки, дополнительно может содержать объект ошибки
+  /// и StackTrace.
+  /// ----------------------------------------------------------------------------
+  void error(String message, [Object? error, StackTrace? stackTrace]);
+}
+
+/// ----------------------------------------------------------------------------
+/// SilentLogger — «тихий» логгер CherryPick. Сообщения игнорируются.
+///
+/// ENGLISH:
+/// SilentLogger ignores all log messages. Used by default in production to
+/// avoid polluting logs with DI events.
+///
+/// RUSSIAN:
+/// SilentLogger игнорирует все события логгирования. Используется по умолчанию
+/// на production, чтобы не засорять логи техническими сообщениями DI.
+/// ----------------------------------------------------------------------------
+class SilentLogger implements CherryPickLogger {
+  const SilentLogger();
+  @override
+  void info(String message) {}
+  @override
+  void warn(String message) {}
+  @override
+  void error(String message, [Object? error, StackTrace? stackTrace]) {}
+}
+
+/// ----------------------------------------------------------------------------
+/// PrintLogger — логгер CherryPick, выводящий все сообщения через print.
+///
+/// ENGLISH:
+/// PrintLogger outputs all log messages to the console using `print()`.
+/// Suitable for debugging, prototyping, or simple console applications.
+///
+/// RUSSIAN:
+/// PrintLogger выводит все сообщения (info, warn, error) в консоль через print.
+/// Удобен для отладки или консольных приложений.
+/// ----------------------------------------------------------------------------
+class PrintLogger implements CherryPickLogger {
+  const PrintLogger();
+  @override
+  void info(String message) => print('[info][CherryPick] $message');
+  @override
+  void warn(String message) => print('[warn][CherryPick] $message');
+  @override
+  void error(String message, [Object? error, StackTrace? stackTrace]) {
+    print('[error][CherryPick] $message');
+    if (error != null) print('  error: $error');
+    if (stackTrace != null) print('  stack: $stackTrace');
+  }
+}

cherrypick/lib/src/scope.dart

@@ -17,12 +17,22 @@ import 'package:cherrypick/src/cycle_detector.dart';
 import 'package:cherrypick/src/global_cycle_detector.dart';
 import 'package:cherrypick/src/binding_resolver.dart';
 import 'package:cherrypick/src/module.dart';
+import 'package:cherrypick/src/logger.dart';
 
-Scope openRootScope() => Scope(null);
+
+CherryPickLogger _globalLogger = const SilentLogger();
+
+Scope openRootScope({CherryPickLogger? logger}) => Scope(null, logger: logger);
 
 class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
   final Scope? _parentScope;
 
+  CherryPickLogger? _logger;
+  
+  @override
+  CherryPickLogger? get logger => _logger;
+  set logger(CherryPickLogger? value) => _logger = value;
+
   /// RU: Метод возвращает родительский [Scope].
   ///
   /// ENG: The method returns the parent [Scope].
@@ -32,9 +42,11 @@ class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
 
   final Map<String, Scope> _scopeMap = HashMap();
 
-  Scope(this._parentScope) {
+  Scope(this._parentScope, {CherryPickLogger? logger}) : _logger = logger ?? _globalLogger {
+    // print removed (trace)
     // Генерируем уникальный ID для скоупа
     setScopeId(_generateScopeId());
+    _logger?.info('Scope created: id=${scopeId ?? "NO_ID"}, parent=${_parentScope?.scopeId}');
   }
 
   final Set<Module> _modulesList = HashSet();
@@ -59,8 +71,8 @@ class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
   /// return [Scope]
   Scope openSubScope(String name) {
     if (!_scopeMap.containsKey(name)) {
-      final childScope = Scope(this);
-      
+      final childScope = Scope(this, logger: logger); // Наследуем логгер вниз по иерархии
+      // print removed (trace)
       // Наследуем настройки обнаружения циклических зависимостей
       if (isCycleDetectionEnabled) {
         childScope.enableCycleDetection();
@@ -68,8 +80,8 @@ class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
       if (isGlobalCycleDetectionEnabled) {
         childScope.enableGlobalCycleDetection();
       }
-      
       _scopeMap[name] = childScope;
+      logger?.info('SubScope created: $name, id=${childScope.scopeId} (parent=$scopeId)');
     }
     return _scopeMap[name]!;
   }
@@ -86,6 +98,7 @@ class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
       if (childScope.scopeId != null) {
         GlobalCycleDetector.instance.removeScopeDetector(childScope.scopeId!);
       }
+      logger?.info('SubScope closed: $name, id=${childScope.scopeId} (parent=$scopeId)');
     }
     _scopeMap.remove(name);
   }
@@ -98,7 +111,13 @@ class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
   Scope installModules(List<Module> modules) {
     _modulesList.addAll(modules);
     for (var module in modules) {
+      logger?.info('Installing module: ${module.runtimeType} in scope $scopeId');
       module.builder(this);
+      // После builder: для всех новых биндингов
+      for (final binding in module.bindingSet) {
+        binding.logger = logger;
+        binding.logAllDeferred();
+      }
     }
     _rebuildResolversIndex();
     return this;
@@ -110,7 +129,7 @@ class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
   ///
   /// return [Scope]
   Scope dropModules() {
-    // [AlexeyYuPopkov](https://github.com/AlexeyYuPopkov) Thank you for the [Removed exception "ConcurrentModificationError"](https://github.com/pese-git/cherrypick/pull/2)
+    logger?.info('Modules dropped from scope: $scopeId');
     _modulesList.clear();
     _rebuildResolversIndex();
     return this;
@@ -130,11 +149,21 @@ class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
   T resolve<T>({String? named, dynamic params}) {
     // Используем глобальное отслеживание, если включено
     if (isGlobalCycleDetectionEnabled) {
-      return withGlobalCycleDetection<T>(T, named, () {
-        return _resolveWithLocalDetection<T>(named: named, params: params);
-      });
+      try {
+        return withGlobalCycleDetection<T>(T, named, () {
+          return _resolveWithLocalDetection<T>(named: named, params: params);
+        });
+      } catch (e, s) {
+        logger?.error('Global cycle detection failed during resolve<$T>', e, s);
+        rethrow;
+      }
     } else {
-      return _resolveWithLocalDetection<T>(named: named, params: params);
+      try {
+        return _resolveWithLocalDetection<T>(named: named, params: params);
+      } catch (e, s) {
+        logger?.error('Failed to resolve<$T>', e, s);
+        rethrow;
+      }
     }
   }
 
@@ -144,8 +173,10 @@ class Scope with CycleDetectionMixin, GlobalCycleDetectionMixin {
     return withCycleDetection<T>(T, named, () {
       var resolved = _tryResolveInternal<T>(named: named, params: params);
       if (resolved != null) {
+        logger?.info('Resolve<$T> [named=$named]: successfully resolved in scope $scopeId.');
         return resolved;
       } else {
+        logger?.error('Failed to resolve<$T> [named=$named] in scope $scopeId.');
         throw StateError(
             'Can\'t resolve dependency `$T`. Maybe you forget register it?');
       }

cherrypick/test/logger_integration_test.dart

@@ -0,0 +1,60 @@
+import 'package:cherrypick/cherrypick.dart';
+import 'package:test/test.dart';
+import 'mock_logger.dart';
+
+class DummyService {}
+
+class DummyModule extends Module {
+  @override
+  void builder(Scope currentScope) {
+    bind<DummyService>().toInstance(DummyService()).withName('test');
+  }
+}
+
+class A {}
+class B {}
+
+class CyclicModule extends Module {
+  @override
+  void builder(Scope cs) {
+    bind<A>().toProvide(() => cs.resolve<B>() as A);
+    bind<B>().toProvide(() => cs.resolve<A>() as B);
+  }
+}
+
+void main() {
+  late MockLogger logger;
+
+  setUp(() {
+    logger = MockLogger();
+  });
+
+  test('Global logger receives Scope and Binding events', () {
+    final scope = Scope(null, logger: logger);
+    scope.installModules([DummyModule()]);
+    final _ = scope.resolve<DummyService>(named: 'test');
+
+    expect(logger.infos.any((m) => m.contains('Scope created')), isTrue);
+    expect(logger.infos.any((m) => m.contains('Binding<DummyService> created')), isTrue);
+    expect(logger.infos.any((m) =>
+        m.contains('Binding<DummyService> named as [test]') || m.contains('named as [test]')), isTrue);
+    expect(logger.infos.any((m) =>
+        m.contains('Resolve<DummyService> [named=test]: successfully resolved') ||
+        m.contains('Resolve<DummyService> [named=test]: successfully resolved in scope')), isTrue);
+  });
+
+  test('CycleDetector logs cycle detection error', () {
+    final scope = Scope(null, logger: logger);
+    scope.enableCycleDetection();
+    scope.installModules([CyclicModule()]);
+    expect(
+      () => scope.resolve<A>(),
+      throwsA(isA<CircularDependencyException>()),
+    );
+    expect(
+      logger.errors.any((m) =>
+        m.contains('CYCLE DETECTED!') || m.contains('Circular dependency detected')),
+      isTrue,
+    );
+  });
+}

cherrypick/test/mock_logger.dart

@@ -0,0 +1,16 @@
+import 'package:cherrypick/cherrypick.dart';
+
+class MockLogger implements CherryPickLogger {
+  final List<String> infos = [];
+  final List<String> warns = [];
+  final List<String> errors = [];
+
+  @override
+  void info(String message) => infos.add(message);
+  @override
+  void warn(String message) => warns.add(message);
+  @override
+  void error(String message, [Object? e, StackTrace? s]) =>
+      errors.add(
+          '$message${e != null ? ' $e' : ''}${s != null ? '\n$s' : ''}');
+}

cherrypick/test/src/cycle_detector_test.dart

@@ -1,7 +1,5 @@
-import 'package:cherrypick/src/cycle_detector.dart';
-import 'package:cherrypick/src/module.dart';
-import 'package:cherrypick/src/scope.dart';
 import 'package:test/test.dart';
+import 'package:cherrypick/cherrypick.dart';
 
 void main() {
   group('CycleDetector', () {

cherrypick/test/src/helper_cycle_detection_test.dart

@@ -1,7 +1,14 @@
 import 'package:cherrypick/cherrypick.dart';
 import 'package:test/test.dart';
+import '../mock_logger.dart';
+import 'package:cherrypick/cherrypick.dart';
 
 void main() {
+  late MockLogger logger;
+  setUp(() {
+    logger = MockLogger();
+    CherryPick.setGlobalLogger(logger);
+  });
   group('CherryPick Cycle Detection Helper Methods', () {
     setUp(() {
       // Сбрасываем состояние перед каждым тестом

doc/full_tutorial_en.md

@@ -313,7 +313,7 @@ final config = await scope.resolveAsync<RemoteConfig>();
 
 [`cherrypick_flutter`](https://pub.dev/packages/cherrypick_flutter) is the integration package for CherryPick DI in Flutter. It provides a convenient `CherryPickProvider` widget which sits in your widget tree and gives access to the root DI scope (and subscopes) from context.
 
-### Features
+## Features
 
 - **Global DI Scope Access:**  
   Use `CherryPickProvider` to access rootScope and subscopes anywhere in the widget tree.
@@ -356,6 +356,26 @@ class MyApp extends StatelessWidget {
 - You can create subscopes, e.g. for screens or modules:  
   `final subScope = CherryPickProvider.of(context).openSubScope(scopeName: "profileFeature");`
 
+---
+
+## Logging
+
+To enable logging of all dependency injection (DI) events and errors in CherryPick, set the global logger before creating your scopes:
+
+```dart
+import 'package:cherrypick/cherrypick.dart';
+
+void main() {
+  // Set a global logger before any scopes are created
+  CherryPick.setGlobalLogger(PrintLogger()); // or your own custom logger
+  final scope = CherryPick.openRootScope();
+  // All DI events and cycle errors will now be sent to your logger
+}
+```
+
+- By default, CherryPick uses SilentLogger (no output in production).
+- Any dependency resolution, scope events, or cycle detection errors are logged via info/error on your logger.
+
 ---
 ## CherryPick is not just for Flutter!
 

doc/full_tutorial_ru.md

@@ -358,6 +358,26 @@ class MyApp extends StatelessWidget {
 - Вы можете создавать подскоупы, если нужно, например, для экранов или модулей:  
   `final subScope = CherryPickProvider.of(context).openSubScope(scopeName: "profileFeature");`
 
+---
+
+## Логирование
+
+Чтобы включить вывод логов о событиях и ошибках DI в CherryPick, настройте глобальный логгер до создания любых scope:
+
+```dart
+import 'package:cherrypick/cherrypick.dart';
+
+void main() {
+  // Установите глобальный логгер до создания scope
+  CherryPick.setGlobalLogger(PrintLogger()); // или свой логгер
+  final scope = CherryPick.openRootScope();
+  // Логи DI и циклов будут выводиться через ваш логгер
+}
+```
+
+- По умолчанию используется SilentLogger (нет логов в продакшене).
+- Любые ошибки резолва и события циклов логируются через info/error на логгере.
+
 ---
 ## CherryPick подходит не только для Flutter!
 

doc/quick_start_en.md

@@ -79,6 +79,24 @@ Example:
     Cherrypick.closeRootScope();
 ```
 
+## Logging
+
+To enable logging of all dependency injection (DI) events and errors in CherryPick, set the global logger before creating your scopes:
+
+```dart
+import 'package:cherrypick/cherrypick.dart';
+
+void main() {
+  // Set a global logger before any scopes are created
+  CherryPick.setGlobalLogger(PrintLogger()); // or your own custom logger
+  final scope = CherryPick.openRootScope();
+  // All DI events and cycle errors will now be sent to your logger
+}
+```
+
+- By default, CherryPick uses SilentLogger (no output in production).
+- Any dependency resolution, scope events, or cycle detection errors are logged via info/error on your logger.
+
 ## Example app
 
 

doc/quick_start_ru.md

@@ -79,6 +79,24 @@ Scope - это контейнер, который хранит все дерев
     Cherrypick.closeRootScope();
 ```
 
+## Логирование
+
+Чтобы включить вывод логов о событиях и ошибках DI в CherryPick, настройте глобальный логгер до создания любых scope:
+
+```dart
+import 'package:cherrypick/cherrypick.dart';
+
+void main() {
+  // Установите глобальный логгер до создания scope
+  CherryPick.setGlobalLogger(PrintLogger()); // или свой логгер
+  final scope = CherryPick.openRootScope();
+  // Логи DI и циклов будут выводиться через ваш логгер
+}
+```
+
+- По умолчанию используется SilentLogger (нет логов в продакшене).
+- Любые ошибки резолва и события циклов логируются через info/error на логгере.
+
 ## Пример приложения