flutter_design_guard 0.1.0-dev.1

Analyzer plugin rules for enforcing Flutter design-system widgets, colors, typography, spacing, and UI standards.

Flutter Design Guard

Analyzer plugin for enforcing Flutter design-system components directly in the IDE, dart analyze, flutter analyze, and CI.

The first rule prevents direct usage of Flutter Material TextField and TextFormField, and recommends the project’s configured replacement widget.

Features

• Detects Flutter Material TextField and TextFormField.
• Uses semantic analysis to avoid false positives from local classes.
• Supports a configurable replacement widget.
• Supports allowed implementation files.
• Allows native fields inside the replacement class.
• Has no runtime or production-bundle impact.

Setup

Enable the plugin in the consuming project’s analysis_options.yaml:

include: package:flutter_lints/flutter.yaml

plugins:
  flutter_design_guard:
    path: ../flutter_design_guard
    diagnostics:
      avoid_native_text_field: true

Restart the Dart Analysis Server after changing the plugin configuration.

Configuration

Create flutter_design_guard.yaml next to the consuming project’s pubspec.yaml:

rules:
  avoid_native_text_field:
    replacement: AppField
    implementation_paths:
      - lib/core/widgets/app_field.dart
      - lib/core/widgets/text_field_helper.dart

Option	Description	Default
replacement	Widget developers should use instead.	CustomTextField
implementation_paths	Package-relative files allowed to use native fields.	[]

Invalid or missing configuration falls back to safe defaults.

Usage

This produces analyzer warnings:

const TextField
();const TextFormField
();

Example diagnostic:

Do not use TextField directly. Use AppField instead.

Use the configured design-system widget:

const AppField
();

Allowed usages

Native text fields are allowed inside the configured replacement class:

class AppField {
  const AppField();

  Object build() {
    return const TextField();
  }
}

They are also allowed inside files listed in implementation_paths.

A local class with the same name does not produce a false warning:

class TextField {
  const TextField();
}

void build() {
  const TextField();
}

Ignoring a diagnostic

For exceptional cases:

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

For an entire file:

// ignore_for_file: avoid_native_text_field

Prefer implementation_paths for design-system implementation files.

Commands

dart test
dart analyze

For a consuming Flutter project:

flutter analyze

No separate lint command is required.

Available rules

avoid_native_text_field

Prevents direct usage of Flutter Material:

• TextField
• TextFormField

Roadmap

Future rules may cover buttons, dialogs, colors, typography, spacing, icons, checkboxes, switches, and other design-system components.

License

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