Refactor how we handle trailers

With the addition of b4 trailers it became pretty obvious that the way
we originally implemented trailers didn't age well. This refactor does
the following:

- introduces LoreTrailer class to replace passing trailers as tuples
- reimplements trailer-order with strict adherence to chain-of-custody
  rules
- adds tests to most common trailer follow-up/ordering cases

Signed-off-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>

1 files changed, 65 insertions, 0 deletions

diff --git a/tests/samples/trailers-followup-custody.mbox b/tests/samples/trailers-followup-custody.mbox
new file mode 100644
index 0000000..0c4e4b8
--- /dev/null
+++ b/tests/samples/trailers-followup-custody.mbox
@@ -0,0 +1,65 @@
+From foo@z Thu Jan  1 00:00:00 1970
+From: Test Test <test@example.com>
+Subject: [PATCH] Simple test
+To: Some List <list-1@lists.example.com>
+Cc: Dev Eloper1 <dev-eloper1@example.com>,
+ Dev Eloper2 <dev-eloper2@example.com>
+Date: Tue, 30 Aug 2022 11:19:07 -0400
+Message-Id: <orig-message@example.com>
+
+Follow-up trailer collating test.
+
+Link: https://msgid.link/some@msgid.here
+Reviewed-by: Original Reviewer <original-reviewer@example.com>
+Signed-off-by: Original Submitter <original-submitter@example.com>
+Suggested-by: Friendly Suggester <suggested-by@example.com>
+Fixes: abcdef01234567890
+Link: https://lore.kernel.org/some@msgid.here  # bug discussion
+Signed-off-by: Test Override <test-override@example.com>
+---
+
+diff --git a/b4/junk.py b/b4/junk.py
+index 12345678..23456789 100644
+--- a/b4/junk.py
+--- b/b4/junk.py
+@@@ -1,1 +1,1 @@ def junk():
+ 
+ 
+-junk1
++junk2
+ 
+ 
+-- 
+2.wong.fu
+
+From foo@z Thu Jan  1 00:00:00 1970
+From: Followup Reviewer1 <followup-reviewer1@example.com>
+Subject: Re: [PATCH] Simple test
+Date: Tue, 30 Aug 2022 11:19:07 -0400
+Message-Id: <fwup-message-1@example.com>
+In-Reply-To: <orig-message@example.com>
+References: <orig-message@example.com>
+
+> This is a simple trailer parsing test.
+
+Reviewed-by: Followup Reviewer1 <followup-reviewer1@example.com>
+
+--
+My sig
+
+From foo@z Thu Jan  1 00:00:00 1970
+From: Followup Reviewer2 <followup-reviewer2@example.com>
+Subject: Re: [PATCH] Simple test
+Date: Tue, 30 Aug 2022 11:19:07 -0400
+Message-Id: <fwup-message-2@example.com>
+In-Reply-To: <fwup-message-1@example.com>
+References: <orig-message@example.com> <fwup-message-1@example.com>
+
+>> This is a simple trailer parsing test.
+> 
+> Reviewed-by: Followup Reviewer1 <reviewer1@example.com>
+
+Tested-by: Followup Reviewer2 <followup-reviewer2@example.com>
+
+--
+My sig