Generating and applying diffs in python

python diff revision difflib
noio picture noio · Feb 21, 2010 · Viewed 18.3k times · Source

Is there an 'out-of-the-box' way in python to generate a list of differences between two texts, and then applying this diff to one file to obtain the other, later?

I want to keep the revision history of a text, but I don't want to save the entire text for each revision if there is just a single edited line. I looked at difflib, but I couldn't see how to generate a list of just the edited lines that can still be used to modify one text to obtain the other.

Answer

Density 21.5 picture Density 21.5 · Feb 21, 2010

Did you have a look at diff-match-patch from google? Apparantly google Docs uses this set of algoritms. It includes not only a diff module, but also a patch module, so you can generate the newest file from older files and diffs.

A python version is included.

http://code.google.com/p/google-diff-match-patch/

Related questions

Python - difference between two strings

I'd like to store a lot of words in a list. Many of these words are very similar. For example I have word afrykanerskojęzyczny and many of words like afrykanerskojęzycznym, afrykanerskojęzyczni, nieafrykanerskojęzyczni. What is the effective (…

Read More
Generate pretty diff html in Python

I have two chunks of text that I would like to compare and see which words/lines have been added/removed/modified in Python (similar to a Wiki's Diff Output). I have tried difflib.HtmlDiff but it's output is less …

Read More
How to print the comparison of two multiline strings in unified diff format?

Do you know any library that will help doing that? I would write a function that prints the differences between two multiline strings in the unified diff format. Something like that: def print_differences(string1, string2): """ Prints the comparison of …

Read More