avoid-functions-in-register-singleton

added in: 1.10.0

warning

Pro+

Warns when a function is passed to registerSingleton.

Passing a function may produce unexpected results. Consider passing an object instance, or use registerFactory or registerLazySingleton instead.

Example

❌ Bad:

void main() {
  // LINT: Passing a function to "registerSingleton" may produce unexpected results. Try passing an object instance, or use "registerFactory" or "registerLazySingleton" instead.
  GetIt.I.registerSingleton(() => SomeClass());

  // LINT: Passing a function to "registerSingleton" may produce unexpected results. Try passing an object instance, or use "registerFactory" or "registerLazySingleton" instead.
  GetIt.instance.registerSingleton(() => SomeClass());

  final getIt = GetIt.instance;
  // LINT: Passing a function to "registerSingleton" may produce unexpected results. Try passing an object instance, or use "registerFactory" or "registerLazySingleton" instead.
  getIt.registerSingleton(() => SomeClass());
}

class SomeClass {}

✅ Good:

void main() {
  GetIt.I.registerLazySingleton(() => SomeClass());
  GetIt.I.registerFactory(() => SomeClass());
  GetIt.I.registerSingleton(SomeClass());
}

class SomeClass {}