Re: [PATCH 2/2] format-patch: move range/inter diff at the end of a single patch output

[Dragan Simic <dsimic@manjaro.org>]

On 2024-05-27 07:19, Patrick Steinhardt wrote:
> On Fri, May 24, 2024 at 02:46:43PM -0700, Junio C Hamano wrote:
>> Patrick Steinhardt <ps@pks.im> writes:
>> > On Thu, May 23, 2024 at 03:50:07PM -0700, Junio C Hamano wrote:
>> > I also think that there's a bug here. The output from the above command
>> > is:
>> > ...
>> >     --- a/blorp
>> >     +++ b/blorp
>> >     @@ -1 +1 @@
>> >     -fnorp
>> >     +fleep
>> >     Interdiff against v1:
>> >       diff --git a/blorp b/blorp
>> > ...
>> >
>> > The diff is before the separator for the signature, and there is no
>> > clear delimiter between the actual diff and the interdiff.
>> 
>> Earlier Eric expressed concern about writing this out _after_ the
>> mail signature mark "-- ", so the output deliberately goes before
>> it.  There is no need for any marker after the last line of the
>> patch.  "Interdiff against ..." is a clear enough delimiter.
>> 
>> FWIW, the parsing of patches has always paid attention to the
>> lengths recorded in @@ ... @@ hunk headers, and the parser notices
>> where the run of ("diff --git a/... b/..." followed by a patch) ends
>> and stops without problems.  On the other hand, if you remove the
>> line "+fleep" in the above example and try to feed it to "git
>> apply", it would correctly notice that it failed to see the expected
>> one line of postimage and complains (because it sees "Interdiff
>> against..."  when it expects to see a line that begins with a plus).
>> 
>> So, I do not see any problem with the output from this cocde at all.
>> 
>> Thanks for careful reading.
> 
> The machine can cope alright. But I think that it's way harder to parse
> for a human if there is no clear visual delimiter between the diff and
> the interdiff. And "Interdiff" isn't quite ideal in my opinion because
> it is text, only, and may be quite easy to miss if it follows a long
> diff.
> 
> The signature mark may not be ideal here as an indicator. Mail readers
> may hide signatures, color them differently or other stuff. But I think
> there should be some indicator here that visually highlights the fact
> that one section is ending and another section is starting. This could
> either be a newline, or the triple-dashes as we use in other places.

I agree about the need for having a distinctive separator.