notmuch show: Include output for the enclosing multipart part of a MIME mail

Previously, the outer multipart part of any multipart/mixed,
multipart/signed, etc. MIME message was silently omitted from the
"notmuch show" output. This prevented any client from correctly
determining to which parts a signature applies, for example.

Now, we actually emit these parts as their own parts. The output is
still flattened---the contained parts are not yet included "within"
the multipart part---so it's still not possible to determine to which
parts a signature applies, but this is one step along the path.

The test suite is updated to reflect this change, (though we'll
eventually want to fix the emacs interface to not display buttons for
the multipart enclosure parts as there's nothing useful for the user
to actually do with them).

notmuch-show.c

@@ -410,6 +410,11 @@ format_part_text (GMimeObject *part, int *part_count)
 	show_part_content (part, stream_stdout);
 	g_object_unref(stream_stdout);
     }
+    else if (g_mime_content_type_is_type (content_type, "multipart", "*"))
+    {
+	/* Do nothing for multipart since its content will be printed
+	 * when recursing. */
+    }
     else
     {
 	printf ("Non-text part: %s\n",

show-message.c

@@ -30,6 +30,9 @@ show_message_part (GMimeObject *part, int *part_count,
 	GMimeMultipart *multipart = GMIME_MULTIPART (part);
 	int i;
 
+	*part_count = *part_count + 1;
+	(*show_part) (part, part_count);
+
 	for (i = 0; i < g_mime_multipart_get_count (multipart); i++) {
 	    show_message_part (g_mime_multipart_get_part (multipart, i),
 			       part_count, show_part);

test/emacs.expected-output/notmuch-show-thread-maildir-storage

@@ -3,6 +3,9 @@ Subject: [notmuch] Working with Maildir storage?
 To: notmuch@notmuchmail.org
 Date: Tue, 17 Nov 2009 14:00:54 -0500
 
+[ multipart/mixed ]
+[ multipart/signed ]
+[ text/plain ]
 I saw the LWN article and decided to take a look at notmuch.  I'm
 currently using mutt and mairix to index and read a collection of
 Maildir mail folders (around 40,000 messages total).
@@ -41,6 +44,9 @@ http://notmuchmail.org/mailman/listinfo/notmuch
  To: notmuch@notmuchmail.org
  Date: Wed, 18 Nov 2009 01:02:38 +0600
 
+ [ multipart/mixed ]
+ [ multipart/signed ]
+ [ text/plain ]
 
  Twas brillig at 14:00:54 17.11.2009 UTC-05 when lars@seas.harvard.edu did gyre and gimble:
 
@@ -68,6 +74,9 @@ http://notmuchmail.org/mailman/listinfo/notmuch
   Cc: notmuch@notmuchmail.org
   Date: Tue, 17 Nov 2009 15:33:01 -0500
 
+  [ multipart/mixed ]
+  [ multipart/signed ]
+  [ text/plain ]
   > See the patch just posted here.
 
   Is the list archived anywhere?  The obvious archives
@@ -148,6 +157,9 @@ http://notmuchmail.org/mailman/listinfo/notmuch
     Cc: notmuch@notmuchmail.org
     Date: Tue, 17 Nov 2009 19:50:40 -0500
 
+    [ multipart/mixed ]
+    [ multipart/signed ]
+    [ text/plain ]
     > I've also pushed a slightly more complicated (and complete) fix to my
     > private notmuch repository
 

test/multipart

@@ -58,19 +58,23 @@ To: cworth@cworth.org
 Date: Tue, 05 Jan 2001 15:43:57 -0000
 header}
 body{
-part{ ID: 1, Content-type: text/plain
+part{ ID: 1, Content-type: multipart/signed
+part}
+part{ ID: 2, Content-type: multipart/mixed
+part}
+part{ ID: 3, Content-type: text/plain
 This is an inline text part.
 part}
-attachment{ ID: 2, Content-type: text/plain
+attachment{ ID: 4, Content-type: text/plain
 Attachment: attachment (text/plain)
 This is a text attachment.
 attachment}
-part{ ID: 3, Content-type: text/plain
+part{ ID: 5, Content-type: text/plain
 And this message is signed.
 
 -Carl
 part}
-part{ ID: 4, Content-type: application/pgp-signature
+part{ ID: 6, Content-type: application/pgp-signature
 Non-text part: application/pgp-signature
 part}
 body}
@@ -78,7 +82,7 @@ Non-text part: application/pgp-signature
 
 test_begin_subtest "Show multipart MIME message (--format=json)"
 output=$(notmuch show --format=json 'id:87liy5ap00.fsf@yoom.home.cworth.org')
-test_expect_equal "$output" '[[[{"id": "87liy5ap00.fsf@yoom.home.cworth.org", "match": true, "filename": "/home/cworth/src/notmuch/test/tmp.multipart/mail/multipart", "timestamp": 978709437, "date_relative": "2001-01-05", "tags": ["attachment","inbox","unread"], "headers": {"Subject": "Multipart message", "From": "Carl Worth <cworth@cworth.org>", "To": "cworth@cworth.org", "Cc": "", "Bcc": "", "Date": "Tue, 05 Jan 2001 15:43:57 -0000"}, "body": [{"id": 1, "content-type": "text/plain", "content": "This is an inline text part.\n"}, {"id": 2, "content-type": "text/plain", "filename": "attachment", "content": "This is a text attachment.\n"}, {"id": 3, "content-type": "text/plain", "content": "And this message is signed.\n\n-Carl\n"}, {"id": 4, "content-type": "application/pgp-signature"}]}, []]]]'
+test_expect_equal "$output" '[[[{"id": "87liy5ap00.fsf@yoom.home.cworth.org", "match": true, "filename": "/home/cworth/src/notmuch/test/tmp.multipart/mail/multipart", "timestamp": 978709437, "date_relative": "2001-01-05", "tags": ["attachment","inbox","unread"], "headers": {"Subject": "Multipart message", "From": "Carl Worth <cworth@cworth.org>", "To": "cworth@cworth.org", "Cc": "", "Bcc": "", "Date": "Tue, 05 Jan 2001 15:43:57 -0000"}, "body": [{"id": 1, "content-type": "multipart/signed"}, {"id": 2, "content-type": "multipart/mixed"}, {"id": 3, "content-type": "text/plain", "content": "This is an inline text part.\n"}, {"id": 4, "content-type": "text/plain", "filename": "attachment", "content": "This is a text attachment.\n"}, {"id": 5, "content-type": "text/plain", "content": "And this message is signed.\n\n-Carl\n"}, {"id": 6, "content-type": "application/pgp-signature"}]}, []]]]'
 
 test_done