Re: Detection of relocations within a file

[Jonathan Nieder <jrnieder@gmail.com>]

Hi Tim,

Tim Mazid wrote:

> I was just wondering if git can/does detect relocations of sections of code/text within a file.
> 
> For example, moving a function from the top of a file to the end.

Depends what you are trying to do.

1. I am mystified by some piece of code, and I want to know where
it originated.  Code movements is uninteresting to me (so grepping
through a patch won't do it).  The command

 $ git log -S'const char git_more_info_string[] =
	"See 'git help COMMAND' for more information on a specific command.";' \
      -- git.c

tells the originating commit pretty quickly.

2. I am mystified not by some particular piece of code but by an
entire file.  The command

 $ git gui blame -- git.c

works okay.

3. The origins of some piece of code make enough sense, but the code
changes since then are a mystery to investigate.  The command

 $ git log -L '/int main(/,/}/' git.c

with git from the "next" branch can help.

4. I want a simple, easy-to-review patch representing a code movement.
No one I know of has worked on this, and if you have ideas for it,
that would be very neat.