Managing the Copy-and-Paste Programming Practice in Modern IDEs

By

Patricia Jablonski

Clarkson University

OOPSLA Doctoral Symposium

October 22, 2007

Managing Copy-and-Paste

Problem

Copy and paste code

Change some variables

But don’t change all instances

So, have an error

ERROR!!

for(i = 1; i < size; i++){ if(array[i] < low) { low = array[i]; }}

for(i = 1; i < size; i++){ if(array[i] < low) { low = array[i]; }}

for(i = 1; i < size; i++){ if(array[i] < low) { low = array[i]; }}

for(i = 1; i < size; i++){ if(array[i] < low) { low = array[i]; }}

for(i = 1; i < size; i++){ if(array[i] < low) { low = array[i]; }}

Copy-and-Paste Error Detection and Prevention

CnP: Copy-and-Paste Tool

Tracks & highlights copy-pasted statements

Detects & prevents inconsistencies based on inferences of the programmer’s intention

Identifier renaming inconsistencies CReN: Consistent Renaming Tool

Lexical/naming pattern inconsistencies

Type inconsistencies

Related Work

Clone detection and removal

Clone tracking tools Codelink, CloneTracker

Error detection tools CP-Miner, DECKARD-based tool

Renaming tools Find & Replace, Rename Refactoring, Linked

Renaming

Conclusion

Discussion

How would you evaluate our tool?

How would you improve the tool? Additional features Visualization of clones Programmer’s intention

Questions/Comments