Flutter Refactor Plugin

A custom lint plugin that encourages declarative widget composition by suggesting the extraction of complex widget trees into separate helper methods or widgets.

This plugin includes the prefer_declarative_over_widget_nesting rule, which flags widget trees that are too deep or complex inside a build method and provides a Quick Fix to extract them with intelligent naming.

Features

• Lint Rule: prefer_declarative_over_widget_nesting detects when structural widgets (like Column, Row, Stack) contain complex children that should be extracted.
• Smart Naming: The Quick Fix automatically suggests meaningful names for extracted methods based on the widget's content (e.g., Text('Login') -> _buildLoginText).
• Context Awareness: Handles l10n variables, context access, and custom widgets gracefully.
• Batch Fix Support: Safely handles "Fix All" operations by coordinating names to avoid collisions (e.g., _buildBorderLine, _buildBorderLine2).
• Cross-Platform Support: Automatically downloads the required native helper binary for your platform (Linux, macOS, Windows) on the first run.

Installation

Add the package to your pubspec.yaml as a dev dependency, along with custom_lint:

dev_dependencies:
  custom_lint: ^0.8.0
  flutter_refactor_plugin: ^1.0.0

Note: The first time you run dart run custom_lint or open the project in your IDE, the plugin will download a small helper binary (~5MB) from GitHub Releases. Internet access is required for this one-time setup.

Usage

Enable the plugin in your analysis_options.yaml:

analyzer:
  plugins:
    - custom_lint

custom_lint:
  rules:
    - prefer_declarative_over_widget_nesting

Example

Before:

Widget build(BuildContext context) {
  return Scaffold(
    body: Column(
      children: [
        Text('Hello'), // Flagged: "Extract this widget..."
        Icon(Icons.star),
      ],
    ),
  );
}

After (Quick Fix):

Widget build(BuildContext context) {
  return Scaffold(
    body: Column(
      children: [
        _buildHelloText(),
        _buildStarIcon(),
      ],
    ),
  );
}

Widget _buildHelloText() {
  return Text('Hello');
}

Widget _buildStarIcon() {
  return Icon(Icons.star);
}