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Comment by neogenix | Hacker News Reader

"In 2.9, Git's diff engine learned a new heuristic: it tries to keep hunk boundaries at blank lines, shifting the hunk "up" whenever the bottom of the hunk matches the bottom of the preceding context, until we hit a blank line. "

I like the new diff improvements

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I don't understand why Git can't just make the [histogram algorithm][1] default, which has better performance than the base Myers algorithm, and is already built to integrate this type of heuristics (without the bugs that caused this patch to get held back).

[1]: http://stackoverflow.com/questions/32365271/whats-the-differ...

In a few (relatively) short years, git's diff has improved on all the other diffs out there.

I didnt even know about the mentioned diff-script: https://github.com/git/git/blob/master/contrib/diff-highligh... It gives pretty nice output :-)

I should definitely learn more about extending git!

There's also this https://github.com/so-fancy/diff-so-fancy

+1 for this. I started using it a few months ago for all my git diffs and I quite like the output. The biggest thing for me is being able to easily see partial line changes.

Requires Node though. Not sure that many people have that installed.

It does not:

> For convenience, the recommended installation is via NPM. If you'd prefer, you may choose to do a manual installation instead. (highlighting by me)

It is written in Perl.

Wait, what? A perl app distributed through NPM? What's next, a node app on CPAN?

Color me perplexed.

There are a lot of non-JS packages in NPM. The Closure compiler, for example.

My favorite git diff extension is the side-by-side diff by cdiff:

https://pypi.python.org/pypi/cdiff

It also features word-level change highlights and other common flares.

I still prefer Araxis.

http://www.araxis.com/merge/index.en

I use: http://www.kaleidoscopeapp.com/

It's the absolute best, been using it for years.

Beyond Compare is the best I've found (especially for complex merges): http://www.scootersoftware.com/

Me too. I tried ataxia for about 6 months and hated it, got told about beyond compare, paid for a license after only a few days of the trial .

Beyond Compare is great. I prefer Araxis. I think most people would be very happy with one of the two. Whichever you happen to prefer.

Cool. BitKeeper internal diff, used for recording history and displaying changes has done this since 2001. https://gist.github.com/wscott/c403526ca19a210c13ad649136c15...

http://bkbits.net/u/bk/bugfix/?PAGE=patch&REV=3bdee65dgEb_uM...

Does anyone know if this only works when displaying diffs, or when generating them? It'd definitely be nice if diffs were more readable when sent to mailing lists, i.e. from git format-patch.

I'm fairly sure this applies only to the generating engine. (Otherwise it'd somehow need to reformat old diffs on the fly.)

Reformat old diffs? If you're under the impression that Git stores diffs you're mistaken. It stores the full file contents and delta-compresses them later.

Diffs in Git are purely a presentation format for human consumption.

> Diffs in Git are purely a presentation format for human consumption.

git format-patch says hi. Obviously the diff engine changes won't apply to already generated text diffs.

You can pipe an existing diff through diff-so-fancy or diff-highlight:

    cat foo.diff | diff-so-fancy

I've never tried, but that's what the doc says.

[time passes]

Oh yes, it seems to work. It doesn't do colors when I try it, but that's probably a misconfiguration on my side. It's how this is intended to be used.

Does anybody know if the new diff heuristic engine takes info from a .gitattributes file in to account? When using git diff to view changes it already makes a difference, see http://urbanautomaton.com/blog/2011/07/28/git-grep-and-langu...

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