Not-quite-a-bug in pickaxe

Not-quite-a-bug in pickaxe

[Johannes Schindelin]

Hi people,

I do not know if I hit that behavior before, but now it hit me big time: 
if a commit moves a certain string from one place to another, "git log 
-S<string>" does not pick up that commit.  The code responsible for this 
is in diffcore-pickaxe.c:

                        else if (!diff_unmodified_pair(p) &&
                                 contains(p->one, needle, len, regexp) !=
                                 contains(p->two, needle, len, regexp))
                                has_changes++;

Basically, the "contains()" method says how often the needle was found, 
and pickaxe just assumes that a move of a string is not interesting 
enough.

Now, this behavior is probably intended, as searching files is much 
cheaper than generating the diffs between them, yet it is something you'll 
have to keep in mind when using "-S".

Ciao,
Dscho

Re: Not-quite-a-bug in pickaxe

[Mikael Magnusson]

2008/11/24 Johannes Schindelin <Johannes.Schindelin@gmx.de>:
> Hi people,
>
> I do not know if I hit that behavior before,

I'm pretty sure it has,
http://thread.gmane.org/gmane.comp.version-control.git/100113/focus=100115
(at least i think that's the same case?)

> but now it hit me big time:
> if a commit moves a certain string from one place to another, "git log
> -S<string>" does not pick up that commit.  The code responsible for this
> is in diffcore-pickaxe.c:
>
>                        else if (!diff_unmodified_pair(p) &&
>                                 contains(p->one, needle, len, regexp) !=
>                                 contains(p->two, needle, len, regexp))
>                                has_changes++;
>
> Basically, the "contains()" method says how often the needle was found,
> and pickaxe just assumes that a move of a string is not interesting
> enough.
>
> Now, this behavior is probably intended, as searching files is much
> cheaper than generating the diffs between them, yet it is something you'll
> have to keep in mind when using "-S".

-- 
Mikael Magnusson

Re: Not-quite-a-bug in pickaxe

[Johannes Schindelin]

Hi,

On Mon, 24 Nov 2008, Mikael Magnusson wrote:

> 2008/11/24 Johannes Schindelin <Johannes.Schindelin@gmx.de>:
>
> > I do not know if I hit that behavior before,
> 
> I'm pretty sure it has, 
> http://thread.gmane.org/gmane.comp.version-control.git/100113/focus=100115 
> (at least i think that's the same case?)

Ah, I finally got around to read Junio's reply.  It did not stick back 
then.

Thanks,
Dscho