Re: [ANNOUNCE] Example Cogito Addon - cogito-bundle

Linus Torvalds [off-list ref] wrote:

On Fri, 20 Oct 2006, Shawn Pearce wrote:

quoted

I renamed hundreds of small files in one shot and also did a few
hundered adds and deletes of other small XML files.  Git generated
a lot of those unrelated adds/deletes as rename/modifies, as their
content was very similiar.  Some people involved in the project
freaked as the files actually had nothing in common with one
another... except for a lot of XML elements (as they shared the
same DTD).

Heh. We can probably tweak the heuristics (one of the _great_ things about 
content detection is that you can fix it after the fact, unlike the 
alternative).

That said, I've personally actually found the content-based similarity 
analysis to often be quite informative, even when (and perhaps 
_especially_ when) it ended up showing something that the actual author of 
the thing didn't intend.

So yeah, I've seen a few strange cases myself, but they've actually been 
interesting. Like seeing how much of a file was just a copyright license, 
and then a file being considered a "copy" just because it didn't actually 
introduce any real new code.

Aside from that one strange case I just mentioned I've always seen
the strategy to work very well.  Its never done something I didn't
expect and I've never seen copies or that I didn't expect to see,
knowing what the author of the change did.

So even though I had a little bit of trouble with that rename
situation above I'm _very_ happy with the way Git handles renames.

And the truth is that case above really was quite correct: XML is
very verbose.  When 70% of the file is just required XML to frame
the other 30% of the file's payload its not surprising that files
are considered to be similar when they only differ by a little bit
of payload.