Do tools exist which automatically find copy-and-paste code?

Question

Hello!

Are there tools out there which could automatically find copy-and-paste code among a set of files?

I was thinking of writing a script for this, which would just search for equal strings, but such script would find mostly irrelevant equalities. (Such as private final static ...).

Answer 1

Yes, try the Copy Paste Detector.

Answer 2

http://patterninsight.com/products/cp-miner.php
Related paper - http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.123.113

Answer 3

The CloneDR is a tool for finding exact and near-miss blocks of code constructed by copy and paste activities. It can handle systems of millions of lines of code.

It uses precise langauge grammars to pick out language structures (identifiers, expressions, statements, blocks, functions, classes, packages, ...) that have been copied, and to determine the points of variation across the sets of clones (any of those structures can be parameters!)

CloneDR operates on a wide variety of languages (C, C++, C#, Java, PHP, COBOL, Python, Ada, Fortran, ...).

The website has a number of sample clone detection reports from a variety of those languages.

EDIT OCT 2010: EGL, and Visual Basic (VBScript, VB6, VB.net) added.

Answer 4

CloneDigger for Python and Java.