nilts #

nilts is lint rules, quick fixes and assists for Dart and Flutter projects that helps you enforce best practices, and avoid errors.

Contents #

• Usage
• Configuration
  • Disabling strategy
  • Enabling strategy
• Lint rules and quick fixes
  • Overview
  • Details
• Assists
• Feature requests
• Bug reports
• Contributing

Usage #

nilts depends on custom_lint.
You should add nilts and custom_lint to your dev_dependencies in pubspec.yaml file.

dev_dependencies:
  custom_lint: <version>
  nilts: <version>

And also, add custom_lint to your analysis_options.yaml file.

analyzer:
  plugins:
    - custom_lint

Configuration #

You can configure all lint rules provided by nilts in analysis_options.yaml file.
Choice one of the following configuration strategies.

Disabling strategy #

All of nilts rules are enabled by default.
Add lint rule name and set false to disable it.

custom_lint:
  rules:
    # Disable particular lint rules if you want ignore them whole package.
    - unnecessary_rebuilds_from_media_query: false

Enabling strategy #

You can disable all lint rules depends on custom_lint by setting enable_all_lint_rules to false.
Add lint rule name and set true to enable it.

custom_lint:
  # Disable all lint rules depends on custom_lint.
  enable_all_lint_rules: false
  rules:
    - unnecessary_rebuilds_from_media_query: true

NOTE: If you enable_all_lint_rules set to false, all of lint rules (not only all of nilts's lint rules) depends on custom_lint will be disabled by default.

Lint rules and quick fixes #

Read below to learn about each lint rules intend to.
Some of lint rules support quick fixes on IDE.

Overview #

Details #

defined_void_callback_type

• Target SDK: Any versions nilts supports
• Rule type: Practice
• Maturity level: Experimental
• Quick fix: ✅

Consider replace void Function() with VoidCallback which is defined in Flutter SDK.

BAD:

final void Function() callback;

GOOD:

final VoidCallback callback;

fixed_text_scale_factor_rich_text

• Target SDK: Any versions nilts supports
• Rule type: Practice
• Maturity level: Experimental
• Quick fix: ✅

Consider adding textScaleFactor argument to RichText constructor to make the text size responsive for user setting.

BAD:

RichText(
  text: TextSpan(
    text: 'Hello, world!',
  ),
)

GOOD:

RichText(
  text: TextSpan(
    text: 'Hello, world!',
  ),
  textScaleFactor: MediaQuery.textScaleFactorOf(context),
)

See also:

• RichText class - widgets library - Dart API

flaky_tests_with_set_up_all

• Target SDK: Any versions nilts supports
• Rule type: Practice
• Maturity level: Experimental
• Quick fix: ✅

Consider using setUp function or initialization on top level or body of test group. setUpAll may cause flaky tests with concurrency executions.

BAD:

setUpAll(() {
  // ...
});

GOOD:

setUp(() {
  // ...
});

void main() {
  // do initialization on top level
  // ...

 group('...', () {
  // or do initialization on body of test group
  // ...
 });
}

See also:

• setUpAll function - flutter_test library - Dart API
• setUp function - flutter_test library - Dart API

shrink_wrapped_scroll_view

• Target SDK: Any versions nilts supports
• Rule type: Practice
• Maturity level: Experimental
• Quick fix: ✅

Consider removing shrinkWrap argument and update the Widget not to shrink wrap.
Shrink wrapping the content of the scroll view is significantly more expensive than expanding to the maximum allowed size because the content can expand and contract during scrolling, which means the size of the scroll view needs to be recomputed whenever the scroll position changes.

You can avoid shrink wrap with 3 steps below in case of your scroll view is nested.

1. Replace the parent scroll view with CustomScrollView.
2. Replace the child scroll view with SliverListView or SliverGridView.
3. Set SliverChildBuilderDelegate to delegate argument of the SliverListView or SliverGridView.

BAD:

ListView(shrinkWrap: true)

GOOD:

ListView(shrinkWrap: false)

See also:

• shrinkWrap property - ScrollView class - widgets library - Dart API
• ShrinkWrap vs Slivers | Decoding Flutter - YouTube

unnecessary_rebuilds_from_media_query

• Target SDK: >= Flutter 3.10.0 (Dart 3.0.0)
• Rule type: Practice
• Maturity level: Experimental
• Quick fix: ✅

Prefer using MediaQuery.xxxOf or MediaQuery.maybeXxxOf instead of MediaQuery.of or MediaQuery.maybeOf to avoid unnecessary rebuilds.

BAD:

final size = MediaQuery.of(context).size;

GOOD:

final size = MediaQuery.sizeOf(context);

Note that using MediaQuery.of or MediaQuery.maybeOf makes sense following cases:

• wrap Widget with MediaQuery overridden MediaQueryData
• observe all changes of MediaQueryData

See also:

• MediaQuery as InheritedModel by moffatman · Pull Request #114459 · flutter/flutter
• MediaQuery class - widgets library - Dart API

Assists #

Upcoming... 🚀

Feature requests #

If you have any feature requests, please create an issue from this template.

Bug reports #

If you find any bugs, please create an issue from this template.

Contributing #

Welcome your contributions!!
Please read CONTRIBUTING docs before submitting your PR.