flutter_design_guard 0.0.1

Custom lint rules for Flutter that enforce design-system widgets, theme colors, typography, spacing, and UI standards.

Flutter Design Guard

Custom lint rules that help Flutter teams enforce their design system directly inside the IDE and CI.

The first rule prevents direct usage of Flutter's native TextField and TextFormField widgets and recommends using CustomTextField instead.

Features

• Reports warnings directly inside supported IDEs.
• Detects Flutter's native TextField.
• Detects Flutter's native TextFormField.
• Recommends using the project's approved design-system component.
• Can run locally and in CI.
• Does not affect the application's runtime or production bundle.

Installation

Add flutter_design_guard and custom_lint to your Flutter application's dev_dependencies:

dev_dependencies:
  custom_lint: ^0.8.1
  flutter_design_guard: ^0.0.1

Install the dependencies:

flutter pub get

This package is a development tool. You do not need to import it into your application's Dart files.

Configuration

Enable custom_lint in your application's analysis_options.yaml:

analyzer:
  plugins:
    - custom_lint

To explicitly enable only the required rules:

analyzer:
  plugins:
    - custom_lint

custom_lint:
  enable_all_lint_rules: false
  rules:
    - avoid_native_text_field

Usage

The following code reports a warning:

TextField();

TextFormField();

The reported warning is:

Do not use TextField or TextFormField directly.
Use CustomTextField instead.

avoid_native_text_field • WARNING

Use the approved design-system component instead:

CustomTextField();

Command-line usage

Run the standard Dart analyzer:

dart analyze

Run Flutter Design Guard rules:

dart run custom_lint

CI usage

Example GitHub Actions steps:

- name: Install dependencies
  run: flutter pub get

- name: Check formatting
  run: dart format --output=none --set-exit-if-changed .

- name: Run Dart analyzer
  run: dart analyze

- name: Run Flutter Design Guard
  run: dart run custom_lint

Ignoring a warning

Ignore one occurrence:

// ignore: avoid_native_text_field
final field = TextField();

Ignore the rule for an entire file:

// ignore_for_file: avoid_native_text_field

Use ignores only for exceptional cases, such as implementing the approved design-system component itself.

Available rules

avoid_native_text_field

Reports a warning when Flutter's native TextField or TextFormField is used directly.

Documentation

See the complete usage guide for IDE setup, CI integration, troubleshooting, and additional examples.

Roadmap

Future releases are planned to include rules for:

• Native Flutter buttons.
• Hardcoded colors outside theme definitions.
• Inline text styles.
• Design-system spacing and radius tokens.
• Native dialogs, snackbars, and loading indicators.
• Configurable replacements and excluded paths.

License

Flutter Design Guard is available under the BSD 3-Clause License. See LICENSE.