When messages are marked, pipe their contents into the specified
command. The messages are ordered according to their respective
Message-Id headers. This allows applying complete patch series with
a single command.
When piping more than one message, make sure to write them in the mbox
format as git am expects them to be.
Link: https://en.wikipedia.org/wiki/Mbox
Link: https://github.com/git/git/blob/v2.35.1/builtin/mailsplit.c#L15-L44
Signed-off-by: Robin Jarry <robin@jarry.cc>
Reviewed-by: Koni Marti <koni.marti@gmail.com>
Tested-by: akspecs <akspecs@gmail.com>