Re: [PATCH 2/3] send-email: accept long lines with suitable transfer encoding

[Eric Sunshine <sunshine@sunshineco.com>]

On Thu, Jul 5, 2018 at 10:24 PM brian m. carlson
<sandals@crustytoothpaste.net> wrote:
> With --validate (which is the default), we warn about lines exceeding
> 998 characters due to the limits specified in RFC 5321.  However, if
> we're using a suitable transfer encoding (quoted-printable or base64),
> we're guaranteed not to have lines exceeding 76 characters, so there's
> no need to fail in this case.  The auto transfer encoding handles this
> specific case, so accept it as well.
>
> Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
> ---
> diff --git a/Documentation/git-send-email.txt b/Documentation/git-send-email.txt
> @@ -401,8 +401,9 @@ have been specified, in which case default to 'compose'.
> -               *       Warn of patches that contain lines longer than 998 characters; this
> -                       is due to SMTP limits as described by http://www.ietf.org/rfc/rfc2821.txt.
> +               *       Warn of patches that contain lines longer than 998 characters unless
> +                       a suitable transfer encoding is used; this is due to SMTP limits as
> +                       described by http://www.ietf.org/rfc/rfc2821.txt.

A reader might like to know what "a suitable transfer encoding" is.
Perhaps add a "such as 'auto', 'quoted-printable' and 'base64'"
comment?

> diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
> @@ -480,6 +480,19 @@ test_expect_success $PREREQ 'long lines with auto encoding are quoted-printable'
> +test_expect_success $PREREQ '--validate passes with certain encodings' '
> +       for enc in auto quoted-printable base64
> +       do
> +               git send-email \
> +                       --from="Example <nobody@example.com>" \
> +                       --to=nobody@example.com \
> +                       --smtp-server="$(pwd)/fake.sendmail" \
> +                       --transfer-encoding=$enc \
> +                       --validate \
> +                       $patches longline.patch
> +       done
> +'

If you turn this inside out, it will be easier to figure out which
encoding fails (if one ever does). That is:

    for enc in auto quoted-printable base64
    do
        test_expect_success $PREREQ "--validate passes with encoding $enc" '
            git send-email ...
        '
    done