Re: Feature request: git cp

From: Kristoffer Haugsbakk <kristofferhaugsbakk@fastmail.com>
Date: Nov 20, 2025, 15:17 UTC
Message-ID: <0e971281-d1c4-4030-9297-f5e2c0765431@app.fastmail.com>
In-Reply-To: <CAL4-wQrgD3nnW2BfNf6e9d7tDANE60dYBRRP_0FW3Z-LvQrZmg@mail.gmail.com>

On Thu, Nov 20, 2025, at 15:56, Martin Guy wrote:

Show 15 quoted lines

> I am splitting a large source file into three smaller ones (mp3.c into
> mad.c, lame.c and twolame.c)
> and would like the history to track the relevant lines in each file,
> like "git mv" does,
> but I only seem able to do this with one file by "git mv"ing it and
> copying that to the other
> as a new file.
>
> So what I'd like is "git cp" that is like "git mv" but where blame for
> both the resulting files
> goes back the original one, if that's possible and unless there's a
> way to achieve the same
> effect that I haven't figured out.
>
> A fairly rare thing to wish to do, but may be useful in this case.

Copies and file moves are detected dynamically when you use things like `git log`.

Try `git log --stat --find-copies-harder`.  I get this output after copying a file three times.

     README.md => rm1.md | 0
     README.md => rm2.md | 0
     README.md => rm3.md | 0
     3 files changed, 0 insertions(+), 0 deletions(-)

I get this output when I change one of the lines in the same commit on one of the files.

     README.md => rm1.md | 2 +-
     README.md => rm2.md | 0
     README.md => rm3.md | 0
     3 files changed, 1 insertion(+), 1 deletion(-)

This is the first time I’ve tried this option so I don’t know more about it.