Copy/Paste detector for source code on JavaScript

on YouTube ↗38m

" summary

Open source copy/paste detector for code uses Rabin–Karp rolling hash over token windows to find duplicated sequences, with a default window of about 70 tokens and a 5‑line minimum to reduce false positives. Tokenization relies on CodeMirror tokenizers so 30+ languages work without custom parsers. Tool outputs CLI and web reports, shows git attribution to indicate who likely copied from whom, has ~700 stars and ~1,000 daily downloads, and uses Bloom‑filter ideas and persisted stores to speed repeated runs.

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" chapters (15)

1. 0:00Introduction
2. 1:27Need for copy/paste detector
3. 5:04Existing solutions search
4. 8:00Robin-Karp algorithm
5. 10:31Code tokenization
6. 12:26App architecture
7. 15:23Tokenizer selection
8. 17:52Language support
9. 19:39Features and reports
10. 22:35Improvement plans
11. 27:04Token normalization
12. 28:55Cross-project search
13. 31:05Engineering challenges
14. 32:27Project development
15. 36:24Current tasks

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