On Fri, 27 Nov 2009 21:49:39 -0500, Bart Trojanowski <bart@jukie.net> wrote:
> This patch changes the default behaviour of notmuch show to display only
> messages that match the search expression.  However, --entire-thread
> option is provided to display all messages in threads that matched the
> search expression.
> 
> It is deemed that will be more useful for human users on the command line.
> Scripts can be modified to include the --entire-thread option so that they
> can display all messages once more.

Thanks Bart.

I've now applied this as well as your following patch to make vim call
"notmuch show" with the --entire-thread option. I also added support to
the emacs client to do the same, and I updated the notmuch man page to
document the option.

Finally, I noticed that not passing the --entire-thread option caused
"notmuch show" to lose all nesting and thread-ordering characteristics,
(even if display the entire thread incidentally). This came from calling
notmuch_query_search_messages (which doesn't do any threading) rather
than notmuch_query_search_threads. So I committed the patch below which
causes it to once again call search_threads and simply not display any
messages that don't match the search when called without
--entire-thread.

I'll be glad if you have any comments to share.

-Carl

commit e1cb6126cc7f66cf71df8880c798f4d0f9d2e411
Author: Carl Worth <cworth@cworth.org>
Date:   Wed Dec 2 16:05:23 2009 -0800

    notmuch show: Preserve thread-ordering and nesting without --entire-thread
    
    When "notmuch show" was recently modified to not show an entire thread
    by default, it also lost all capability to properly order the messages
    in a thread and to print their proper depth. For example, the command:
    
    	notmuch show thread:6d5e3e276461188c5778c9f219f63782
    
    had dramatically different output than:
    
    	notmuch show --entire-thread thread:6d5e3e276461188c5778c9f219f63782
    
    even though both commands were selecting and displaying the same set
    of messages. The first command would diplay them "flat", (all with
    depth:0), and in strict date order; while the second command would
    display them "nested" (with depth based on threading), and in thread
    order.
    
    We now fix "notmuch show" without the --entire-thread option to also
    display nested and thread-ordered messages.
    
    If some messages in the thread are not included in the displayed
    results, then they are not counted when computing depth values.

diff --git a/notmuch-show.c b/notmuch-show.c
index 60339d0..376aacd 100644
--- a/notmuch-show.c
+++ b/notmuch-show.c
@@ -184,9 +184,12 @@ show_message (void *ctx, notmuch_message_t *message, int indent)
 
 
 static void
-show_messages (void *ctx, notmuch_messages_t *messages, int indent)
+show_messages (void *ctx, notmuch_messages_t *messages, int indent,
+	       notmuch_bool_t entire_thread)
 {
     notmuch_message_t *message;
+    notmuch_bool_t match;
+    int next_indent;
 
     for (;
 	 notmuch_messages_has_more (messages);
@@ -194,9 +197,17 @@ show_messages (void *ctx, notmuch_messages_t *messages, int indent)
     {
 	message = notmuch_messages_get (messages);
 
-	show_message (ctx, message, indent);
+	match = notmuch_message_get_flag (message, NOTMUCH_MESSAGE_FLAG_MATCH);
 
-	show_messages (ctx, notmuch_message_get_replies (message), indent + 1);
+	next_indent = indent;
+
+	if (match || entire_thread) {
+	    show_message (ctx, message, indent);
+	    next_indent = indent + 1;
+	}
+
+	show_messages (ctx, notmuch_message_get_replies (message),
+		       next_indent, entire_thread);
 
 	notmuch_message_destroy (message);
     }
@@ -257,29 +268,21 @@ notmuch_show_command (void *ctx, unused (int argc), unused (char *argv[]))
 	return 1;
     }
 
-    if (!entire_thread) {
-	messages = notmuch_query_search_messages (query);
-	if (messages == NULL)
-	    INTERNAL_ERROR ("No messages.\n");
-	show_messages (ctx, messages, 0);
-
-    } else {
-	for (threads = notmuch_query_search_threads (query);
-		notmuch_threads_has_more (threads);
-		notmuch_threads_advance (threads))
-	{
-	    thread = notmuch_threads_get (threads);
+    for (threads = notmuch_query_search_threads (query);
+	 notmuch_threads_has_more (threads);
+	 notmuch_threads_advance (threads))
+    {
+	thread = notmuch_threads_get (threads);
 
-	    messages = notmuch_thread_get_toplevel_messages (thread);
+	messages = notmuch_thread_get_toplevel_messages (thread);
 
-	    if (messages == NULL)
-		INTERNAL_ERROR ("Thread %s has no toplevel messages.\n",
-			notmuch_thread_get_thread_id (thread));
+	if (messages == NULL)
+	    INTERNAL_ERROR ("Thread %s has no toplevel messages.\n",
+			    notmuch_thread_get_thread_id (thread));
 
-	    show_messages (ctx, messages, 0);
+	show_messages (ctx, messages, 0, entire_thread);
 
-	    notmuch_thread_destroy (thread);
-	}
+	notmuch_thread_destroy (thread);
     }
 
     notmuch_query_destroy (query);