HEADS-UP: new Git hook linters for whitespace & commit msgs

[Herbert Valerio Riedel]

Hi Edward,

On 2015-03-09 at 19:58:28 +0100, Edward Z. Yang wrote:
> I tried to push today and I noticed that there is an unfortunate
> interaction between Arcanist's commit rewriting and the Signed-off-by
> hook, which requires the Signed-off-by line to be on a new-line by
> itself.  The problem is Arcanist, by default, rewrites a one line
> commit message to:
>
> This is my first line
>
> Summary: Signed-off-by: Edward <... at ...>
>
> which fails lint.
>
> This is pretty annoying; can we relax the lint check or get arc to
> stop messing this up?

I'd *love* to get Arcanist to stop blatantly violating Git's commit msg
conventions. For starters, it violates Git's property-trailer syntax
convention which requires whitespace-free headings, like 'Reviewed-by:'
rather than 'Reviewed By:', c.f.

  http://git-htmldocs.googlecode.com/git/git-interpret-trailers.html

and

  https://git.wiki.kernel.org/index.php/CommitMessageConventions

Otoh, the 'Summary:' "trailer" emitted by Arcanist is completely
superfluous and conveys no useful information, but more importantly
results in ugly Git commit messages because now the commit msg body
always starts with that redundant 'Summary: '-prologue (which then can
break the 'Signed-off-by:'-trailer like in your case, causing tooling
not to recognize it anymore -- that's why I added that specific
lint-check).



Cheers,
  hvr