passsy / avoid-singletonsr3

Avoid Singletons

Public

Inject dependencies instead of reaching for a singleton, so tests can replace them with a fake or a mock.

Avoid Singletons

Inject dependencies instead of reaching for a singleton, so tests can replace them with a fake or a mock.

Single instances shared via context or a service locator are fine.
But don't create singletons for the sake of making it easy to call from anywhere.
Always try to inject things so that they can be replaced with a mock/fake in unit tests.

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Revision: 3
Hash: 49d463d6237f
Runs on: write, prompt
Files: **/*.dart !**/*.{g,freezed,gr,config,mocks}.dart
Tags: dart
Detector API: 3
Packages: dart-kit github:passsy/principles#90ea8c14d80b98b7cc6e5ccbea2906e1422934d7 (MIT)
Expert: @passsy

third-party noticesthe licences in the bundle

This detector contains code of the packages below. Each is used under its own licence.

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dart-kit 0.1.0
License: MIT
Source: https://github.com/passsy/principles/tree/90ea8c14d80b98b7cc6e5ccbea2906e1422934d7
Copyright (c) 2026 Pascal Welsch

LICENSE:

MIT License

Copyright (c) 2026 Pascal Welsch

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

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