Re: Bug Report: Superfluous Tab Characters
- From
- Diogo Fernandes <diogoabfernandes@gmail.com>
- Date
- Feb 5, 2023, 17:01 UTC
- Message-ID
- <CADPR2CWzjiPJn9ZtkcU0ZTbacq5JQu2vXriuLq+VreqqUo_-dA@mail.gmail.com>
- In-Reply-To
- <CAN0heSruSHQk8cPZ1-Zhp8dfL+j-OAsASrsBTVdWKQcx14Pxtw@mail.gmail.com>
Hi Martin,
I am not personally parsing the output of git. This was rather observed while using a third-party tool that reads the output of git as initially pointed out by https://github.com/trufflesecurity/trufflehog/issues/1060.
I have the latest v2.39.1 from `brew` on macOS and the tab character is added to the output.
Anyhow, thanks for checking.
Regards, Diogo
On Sun, Feb 5, 2023 at 4:28 PM Martin Ågren <martin.agren@gmail.com> wrote:
Show 48 quoted lines
>
> On Sat, 4 Feb 2023 at 13:54, Diogo Fernandes <diogoabfernandes@gmail.com> wrote:
> > On Fri, 3 Feb 2023 at 14:43 Martin Ågren <martin.agren@gmail.com> wrote:
> >>
> >> On Fri, 3 Feb 2023 at 13:50, Diogo Fernandes <diogoabfernandes@gmail.com> wrote:
> >> >
> >> > I have run into a bug where git seems to be adding superfluous tabs to
> >> > the end of filenames that contain a space. I have attached the output
> >> > of `git bugreport` for your review. Feel free to have a look
> >> > https://github.com/trufflesecurity/trufflehog/issues/1060 for
> >> > additional context.
> >>
> >> The code that adds this tab in the output of `git log` and friends has
> >> changed a bit since it was originally added in 1a9eb3b9d5
> >> ("git-diff/git-apply: make diff output a bit friendlier to GNU patch
> >> (part 2)", 2006-09-22), but in that commit you can see the original
> >> motivation.
>
> > So, this is by design and not a bug? And is it still current in the latest version of git?
>
> Yes, it appears to be by design:
>
> Somebody was wondering on #git channel why a git generated diff
> does not apply with GNU patch when the filename contains a SP.
> It is because GNU patch expects to find TAB (and trailing timestamp)
> on ---/+++ (old_name and new_name) lines after the filenames.
>
> The "diff --git" output format was carefully designed to be
> compatible with GNU patch where it can, but whitespace
> characters were always a pain.
>
> This adds an extra TAB (but not trailing timestamp) to old_name
> and new_name lines of git-diff output when the filename has a SP
> in it. An earlier patch updated git-apply to prepare for this.
>
> From a quick test, this behavior does seem to be in newest git.
>
> I sense there is some sort of ulterior motive here that hasn't come
> across yet. Are you trying to parse the output of `git log` to find
> something? Would `git diff-tree` work, e.g., if you're mostly just after
> the filenames involved? Depending on what you're trying to achieve, it
> could be a bit simpler to parse `git diff-tree` and other "plumbing"
> commands, rather than `git log` and other such "porcelain" commands.
>
> (Also, note that one person's `git log` output can be different from
> yours, e.g., because of various config knobs being set different ways.)
>
> Martin