As reported by Sean Whitton, there are mailers (in particular the
Debian Bug Tracking System) that have sensible In-Reply-To headers,
but un-useful-for-notmuch References (in particular with the BTS, the
oldest reference is last). I looked at a sample of about 200K
messages, and only about 0.5% these had something other than a single
message-id in In-Reply-To. On this basis, if we see a single
message-id in In-Reply-To, consider that as authoritative.
In a future commit, we will start trusting In-Reply-To's when they
look sane (i.e. a single message-id). Modify these tests so they will
keep passing (i.e. keep choosing References) when that happens.
The current scheme of choosing the replyto (i.e. the default parent
for threading purposes) does not work well for mailers that put
the oldest Reference last.
We (finally) implement the XXX comment. It requires a bit of care not
to reparent all of the possible toplevel messages.
_notmuch_messages_has_next is not ready to be a public function yet,
since it punts on the mset case. We know in the one case it is called,
the notmuch_messages_t is just a regular list / iterator.
This is mainly to lay out the structure of the final code. The problem
isn't really solved yet, although some very simple cases are
better (hence the fixed test). We need two passes through the messages
because we need to be careful not to re-parent too many messages and
end up without any toplevel messages.
For non-root messages, this should not should anything currently, as
the messages are already added in date order. In the future we will
add some non-root messages in a second pass out of order and the
sorting will be useful. It does fix the order of multiple
root-messages (although it is overkill for that).
This documents the bug discussed at
id:87efgmmysi.fsf@len.workgroup
The underlying issue is that the reply to a ghost (missing) message is
falsely classified as a root message in _resolve_thread_relationships.
There are two pairs of tests; in each case the the first test is
simpler / more robust, but also easier to fool.
Instead of just having the first filename for the message, list all
duplicate filenames of the message as a list in the formatted
outputs. This bumps the format version to 3.
The files (test) scripts source (with builtin command `.`) provides
information which the scripts depend, and without the `source` to
succeed allowing script to continue may lead to dangerous situations
(e.g. rm -rf "${undefined_variable}"/*).
At the end of all source (.) lines construct ' || exit 1' was added;
In our case the script script will exit if it cannot find (or read) the
file to be sourced. Additionally script would also exits if the last
command of the sourced file exited nonzero.
According to RFC2822 References and In-Reply-To headers are supposed
to contain one or more Message-IDs, however older RFC822 allowed
almost any content. When both References and In-Reply-To headers ends
with something else that a Message-ID (see e.g. [1]), the thread
structure presented by notmuch is incorrect. The reason is that
notmuch treats this case as if the email contained no "replyto"
information (see _notmuch_database_link_message_to_parents).
This patch changes the parse_references() function to return the last
valid Message-ID encountered rather than NULL resulting from the last
hunk of text not being the Message-ID.
[1] https://lkml.org/lkml/headers/2014/5/19/864
All test scripts to be executed are now named as T\d\d\d-name.sh,
numers in increments of 10.
This eases adding new tests and developers to see which are test scripts
that are executed by test suite and in which order.
