Re: git pretty format: "%+b" not working with "%w" in front of it?

From: Jeff King <peff@peff.net>
Date: Mar 15, 2017, 15:18 UTC
Message-ID: <20170315151853.c3mn7xyc5fqmkkn4@sigill.intra.peff.net>
In-Reply-To: <CAHd499BP-iaXJDNg+4RWB9GaQ1xW8ZnH0oysWSa7u_DCSWFFDg@mail.gmail.com>

On Wed, Mar 15, 2017 at 09:08:10AM -0500, Robert Dailey wrote:

Show 26 quoted lines

> $ git log
> 
> commit 7ffb909bb8f38607e3d6d9f3504a66ca978f0ac2
> Author: Robert Dailey <robert@ziosk.com>
> Date:   Mon Dec 12 11:01:00 2016 -0600
> 
>     Add initial skeleton files & a few interfaces for new kizi/sc16 stuff
> 
>     This is still FAR from complete....
> 
> 
> I want to generate changelogs, using github markdown list format. I
> tried doing that using this command:
> 
> $ git log --pretty=format:"* %s%n%w(100,2,2)%+b"
> 
> However, the 2nd newline is not inserted:
> 
> * Add initial skeleton files & a few interfaces for new kizi/sc16 stuff
>    This is still FAR from complete....
> 
> The format I'm expecting is:
> 
> * Add initial skeleton files & a few interfaces for new kizi/sc16 stuff
> 
>   This is still FAR from complete....

Hmm. I think the leading newline is added, but it gets eaten by the wrapping code. If I run your example in a debugger, we enter strbuf_add_wrapped_text() with:

  buf = "* the subject line\n"
  text = "\nthe body text"
  indent1=2, indent2=2, width=100

Which looks right. But the wrapping code seems to treat blank lines oddly. I can't quite figure out what it's _trying_ to do, but if there's one blank line, it gets converted into a space (and thus the weird three-space indent you see). But if there are two, they are both preserved!

So I think the line-wrapping code is simply buggy, and you are not doing anything wrong. But maybe I am missing some subtle case.

-Peff