Show HN: Treepeat – Code similarity detection using Tree-sitter
github.comtreepeat is a tool that finds similarities in your codebase.
Find duplicate code blocks meaningful to the language (classes/functions), not just lines.
Find near-duplicates: ignore whitespace, strings, high level AST nodes such as function and names.
Find structurally similar code: anonymize identifiers, constants, etc.
Pull requests welcome: This is very much an proof of concept - I'm happy with it, but I haven't supported very many languages at present.
Languages supported: astro, bash, css, go, html, javascript, lua, markdown (plus codeblocks), python, sql, typescript, java, kotlin, rust, yaml
This is what I wanted to help with duplicate code detection, which is now a real problem with agentic programming since the agent tends to duplicate helper functions a lot in bigger codebases.
I ended up writing my own tool [1] that uses vector search, which works but can be unusably slow in large codebases.
I will give this a shot.
Thanks for posting this; I'm very interested in finding similar chunks of code in an AST-ish fashion, and using tree-sitter seems perfect.