Re: git format-patch produces invalid patch if the commit adds an empty file?

[Adam Williamson <awilliam@redhat.com>]

On Fri, 2021-08-20 at 06:15 +0000, Gwyneth Morgan wrote:
> On 2021-08-19 14:09:43-0700, Junio C Hamano wrote:
> > I do not think our patch injestion machinery in "git apply" minds if
> > we added the "--- /dev/null" + "+++ b/<path>" headers (and the
> > reverse for removal of an empty file) to the current output, and I
> > am not fundamentally opposed to such a change.
> > 
> > But because it is such a rare event (and a discouraged practice) to
> > record a completely empty file, I wouldn't place a high priority on
> > doing so myself.
> 
> GNU patch chokes in this case with an unquoted filename with spaces.
> However if we output
> 
> 	diff --git "a/test cases/common/56 array methods/a.txt" "b/test cases/common/56 array methods/a.txt"
> 
> instead of
> 
> 	diff --git a/test cases/common/56 array methods/a.txt b/test cases/common/56 array methods/a.txt
> 
> GNU patch (and Git) will read it correctly. Rather than adding the "---"
> "+++" lines, could we instead quote filenames in the "diff --git" line
> when they contain spaces?

Aha, I did actually wonder about that, because even with the added
lines, the patches don't apply (via `patch`) on Fedora 33 and 34 (and
the error message after adding the lines does seem to indicate the
spaces in the filenames as the culprit). They only apply on Fedora 35
and 36. I hadn't thought to just add quote marks, though of course it
seems obvious now. So yeah, that seems likely to be the best fix. I'll
try and confirm your results tomorrow. Thanks!
-- 
Adam Williamson
Fedora QA
IRC: adamw | Twitter: adamw_ha
https://www.happyassassin.net