Merge branch 'ao/send-email-irt'

* ao/send-email-irt:
  git-send-email.perl: make initial In-Reply-To apply only to first email
  t9001: send-email interation with --in-reply-to and --chain-reply-to

3 files changed, 65 insertions, 6 deletions

diff --git a/Documentation/git-send-email.txt b/Documentation/git-send-email.txt
index 05904e0e7f..ebc024ae3d 100644
--- a/Documentation/git-send-email.txt
+++ b/Documentation/git-send-email.txt
@@ -82,11 +82,26 @@ See the CONFIGURATION section for 'sendemail.multiedit'.
 	set, as returned by "git var -l".
 
 --in-reply-to=<identifier>::
-	Specify the contents of the first In-Reply-To header.
-	Subsequent emails will refer to the previous email
-	instead of this if --chain-reply-to is set.
-	Only necessary if --compose is also set.  If --compose
-	is not set, this will be prompted for.
+	Make the first mail (or all the mails with `--no-thread`) appear as a
+	reply to the given Message-Id, which avoids breaking threads to
+	provide a new patch series.
+	The second and subsequent emails will be sent as replies according to
+	the `--[no]-chain-reply-to` setting.
++
+So for example when `--thread` and `--no-chain-reply-to` are specified, the
+second and subsequent patches will be replies to the first one like in the
+illustration below where `[PATCH v2 0/3]` is in reply to `[PATCH 0/2]`:
++
+  [PATCH 0/2] Here is what I did...
+    [PATCH 1/2] Clean up and tests
+    [PATCH 2/2] Implementation
+    [PATCH v2 0/3] Here is a reroll
+      [PATCH v2 1/3] Clean up
+      [PATCH v2 2/3] New tests
+      [PATCH v2 3/3] Implementation
++
+Only necessary if --compose is also set.  If --compose
+is not set, this will be prompted for.
 
 --subject=<string>::
 	Specify the initial subject of the email thread.
diff --git a/git-send-email.perl b/git-send-email.perl
index 6e2d79ac66..76565de2ee 100755
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -1319,7 +1319,8 @@ foreach my $t (@files) {
 
 	# set up for the next message
 	if ($thread && $message_was_sent &&
-		(chain_reply_to() || !defined $reply_to || length($reply_to) == 0)) {
+		(chain_reply_to() || !defined $reply_to || length($reply_to) == 0 ||
+		$message_num == 1)) {
 		$reply_to = $message_id;
 		if (length $references > 0) {
 			$references .= "\n $message_id";
diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
index d1ba25205b..5e48318013 100755
--- a/t/t9001-send-email.sh
+++ b/t/t9001-send-email.sh
@@ -313,6 +313,49 @@ test_expect_success $PREREQ 'Valid In-Reply-To when prompting' '
 	! grep "^In-Reply-To: < *>" msgtxt1
 '
 
+test_expect_success $PREREQ 'In-Reply-To without --chain-reply-to' '
+	clean_fake_sendmail &&
+	echo "<unique-message-id@example.com>" >expect &&
+	git send-email \
+		--from="Example <nobody@example.com>" \
+		--to=nobody@example.com \
+		--no-chain-reply-to \
+		--in-reply-to="$(cat expect)" \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		$patches $patches $patches \
+		2>errors &&
+	# The first message is a reply to --in-reply-to
+	sed -n -e "s/^In-Reply-To: *\(.*\)/\1/p" msgtxt1 >actual &&
+	test_cmp expect actual &&
+	# Second and subsequent messages are replies to the first one
+	sed -n -e "s/^Message-Id: *\(.*\)/\1/p" msgtxt1 >expect &&
+	sed -n -e "s/^In-Reply-To: *\(.*\)/\1/p" msgtxt2 >actual &&
+	test_cmp expect actual &&
+	sed -n -e "s/^In-Reply-To: *\(.*\)/\1/p" msgtxt3 >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success $PREREQ 'In-Reply-To with --chain-reply-to' '
+	clean_fake_sendmail &&
+	echo "<unique-message-id@example.com>" >expect &&
+	git send-email \
+		--from="Example <nobody@example.com>" \
+		--to=nobody@example.com \
+		--chain-reply-to \
+		--in-reply-to="$(cat expect)" \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		$patches $patches $patches \
+		2>errors &&
+	sed -n -e "s/^In-Reply-To: *\(.*\)/\1/p" msgtxt1 >actual &&
+	test_cmp expect actual &&
+	sed -n -e "s/^Message-Id: *\(.*\)/\1/p" msgtxt1 >expect &&
+	sed -n -e "s/^In-Reply-To: *\(.*\)/\1/p" msgtxt2 >actual &&
+	test_cmp expect actual &&
+	sed -n -e "s/^Message-Id: *\(.*\)/\1/p" msgtxt2 >expect &&
+	sed -n -e "s/^In-Reply-To: *\(.*\)/\1/p" msgtxt3 >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success $PREREQ 'setup fake editor' '
 	(echo "#!$SHELL_PATH" &&
 	 echo "echo fake edit >>\"\$1\""