In older versions of git, we used rfc822 header folding to
indicate that the original subject line had multiple lines
in it. But since a1f6baa (format-patch: wrap long header
lines, 2011-02-23), we now use header folding whenever there
is a long line.
This means that "git am" cannot trust header folding as a
sign from format-patch that newlines should be preserved.
Instead, format-patch needs to signal more explicitly that
the newlines are significant. This patch does so by
rfc2047-encoding the newlines in the subject line. No
changes are needed on the "git am" end; it already decodes
the newlines properly.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Without the "-k" option, mailinfo will convert a folded
subject header like:
Subject: this is a
subject that doesn't
fit on one line
into a single line. With "-k", however, we assumed that
these newlines were significant and represented something
that the sending side would want us to preserve.
For messages created by format-patch, this assumption was
broken by a1f6baa (format-patch: wrap long header lines,
2011-02-23). For messages sent by arbitrary MUAs, this was
probably never a good assumption to make, as they may have
been folding subjects in accordance with rfc822's line
length recommendations all along.
This patch now joins folded lines with a single whitespace
character. This treats header folding purely as a syntactic
feature of the transport mechanism, not as something that
format-patch is trying to tell us about the original
subject.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit a1f6baa (format-patch: wrap long header lines,
2011-02-23) changed format-patch's behavior with respect to
long header lines, but made no accompanying changes to the
receiving side. It was thought that "git am" would handle
these folded subjects fine, but there is a regression when
using "am -k".
Let's add a test documenting this. While we're at it, let's
give more complete test coverage to document what should be
happening in each case. We test three types of subjects:
a short one, one long enough to require wrapping, and a
multiline subject. For each, we test these three
combinations:
format-patch | am
format-patch -k | am
format-patch -k | am -k
We don't bother testing "format-patch | am -k", which is
nonsense (you will be adding in [PATCH] cruft to each
subject).
This reveals the regression above (long subjects have
linebreaks introduced via "format-patch -k | am -k"),
as well as an existing non-optimal behavior (multiline
subjects are not preserved using "-k").
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King