From: Eric Wong <e@80x24.org>
Date: Mon, 29 Nov 2021 17:26:18 GMT
Subject: Re: [RFC PATCH v1 1/1] docs: add the new commit-msg tags 'Reported:' and 'Reviewed:'
Message-ID: <20211129172618.GA26651@dcvr>
In-Reply-To: <87mtlnjhj6.fsf@intel.com>

Jani Nikula <jani.nikula@intel.com> wrote:
> From the RFC nitpicking department, msg-id is allowed to contain CFWS
> (comments and folding white space) outside the angle brackets, which
> means you could have RFC compliant Message-ID header field:
> 
> Message-ID: 
>   <message-id@example.com>
> 
> or
> 
> Message-ID: (comment) 
>   <message-id@example.com>
> 
> or even worse, really.
> 
> The moral of the story is that you should always offload the header
> parsing to some tool or library designed to do that.

It's a bit much for common cases with git-send-email and
reasonable MUAs, I think.  I don't know if formail is commonly
installed, nowadays...

Fwiw, the code running lore uses something like this:

	/^Message-ID:[ \t]*([^\n]*\r?\n # 1st line
			# continuation lines:
			(?:[^:\n]*?[ \t]+[^\n]*\r?\n)*)
			/ismx

I'm fine with this non-trivial regexp being included with
GPL-2.0 code; but it could be too big for a one-liner *shrug*

... And <([^>]+)>/s to extract Message-IDs, but ISTR the code
behind lore doesn't handle spaces inside <> properly, but I'm
not sure if there's enough valid, non-spam messages with them...