clonescope

clonescope is a Dart CLI that finds structurally duplicated Dart and Flutter code.

It parses source files with the Dart analyzer, normalizes identifiers and literals, clusters matching method and function bodies, and ranks the results so higher-risk duplicates show up first.

The current ranking model favors:

• data-layer and service-layer duplication
• async flows, error handling, and branching logic
• duplicates spread across different files or folders

It de-prioritizes:

• build()-heavy UI duplication
• short boilerplate methods such as copyWith()
• test files, unless explicitly included

Install

dart pub global activate clonescope

Then run:

clonescope /path/to/flutter_or_dart_repo

Usage

clonescope <path> [--min-lines N] [--min-tokens N] [--top N] [--include-tests] [--include-boilerplate] [--json]

Examples:

clonescope ~/projects/orchard/realaf-app
clonescope ~/projects/orchard/realaf-app --top 50
clonescope ~/projects/orchard/realaf-app --include-tests --json

Output

Example output:

Found 45 duplicate groups in 703 Dart files.

[score 796] 2 occurrences, 60 lines, 330 normalized tokens
why: base=590, architecture+95, logic+111
shape: async { try { if ( id . id . id == id . id ) return null
  - lib/data/leaderboard_repo.dart:202 (method getUserWeeklyRank)
  - lib/data/leaderboard_repo.dart:264 (method getUserMonthlyRank)

How It Works

clonescope currently:

1. Walks a Dart or Flutter repository recursively.
2. Ignores generated files such as .g.dart, .freezed.dart, and build output.
3. Parses each Dart file with package:analyzer.
4. Extracts function and method bodies.
5. Normalizes identifiers, strings, and numeric literals into stable token shapes.
6. Groups exact normalized matches.
7. Ranks the groups using architecture-aware heuristics.

Current architecture hints include:

• lib/data/
• lib/services/
• lib/usecases/
• lib/core/
• lib/navigation/
• lib/ui/
• lib/ui/widgets/
• lib/models/
• test/

Status

This is an early version focused on exact normalized matches.

Planned improvements:

• near-clone detection with small inserted or removed statements
• richer Flutter folder-architecture heuristics
• machine-readable output for CI reporting
• analyzer plugin integration for inline diagnostics

Development

Run locally:

dart analyze
dart test
dart run bin/clonescope.dart /path/to/repo

Publishing Notes

Before publishing to pub.dev, run:

dart pub publish --dry-run

Then publish:

dart pub publish