Merge branch 'lh/send-email-hide-x-mailer'

"git send-email" normally identifies itself via X-Mailer: header
in the message it sends out.  A new command line flag allows the
user to squelch the header.

* lh/send-email-hide-x-mailer:
  test/send-email: --[no-]xmailer tests
  send-email: add --[no-]xmailer option

Documentation/config.txt

@@ -2329,6 +2329,7 @@ sendemail.smtpuser::
 sendemail.thread::
 sendemail.transferencoding::
 sendemail.validate::
+sendemail.xmailer::
 	See linkgit:git-send-email[1] for description.
 
 sendemail.signedoffcc::

Documentation/git-send-email.txt

@@ -141,6 +141,11 @@ Note that no attempts whatsoever are made to validate the encoding.
 	configuration value; if that is unspecified, git will use 8bit and not
 	add a Content-Transfer-Encoding header.
 
+--xmailer::
+--no-xmailer::
+	Add (or prevent adding) the "X-Mailer:" header.  By default,
+	the header is added, but it can be turned off by setting the
+	`sendemail.xmailer` configuration variable to `false`.
 
 Sending
 ~~~~~~~

git-send-email.perl

@@ -54,6 +54,7 @@ sub usage {
     --[no-]bcc              <str>  * Email Bcc:
     --subject               <str>  * Email "Subject:"
     --in-reply-to           <str>  * Email "In-Reply-To:"
+    --[no-]xmailer                 * Add "X-Mailer:" header (default).
     --[no-]annotate                * Review each patch that will be sent in an editor.
     --compose                      * Open an editor for introduction.
     --compose-encoding      <str>  * Encoding to assume for introduction.
@@ -154,7 +155,7 @@ sub format_2822_time {
 # Variables we fill in automatically, or via prompting:
 my (@to,$no_to,@initial_to,@cc,$no_cc,@initial_cc,@bcclist,$no_bcc,@xh,
 	$initial_reply_to,$initial_subject,@files,
-	$author,$sender,$smtp_authpass,$annotate,$compose,$time);
+	$author,$sender,$smtp_authpass,$annotate,$use_xmailer,$compose,$time);
 
 my $envelope_sender;
 
@@ -226,7 +227,8 @@ sub do_edit {
     "signedoffcc" => [\$signed_off_by_cc, undef],      # Deprecated
     "validate" => [\$validate, 1],
     "multiedit" => [\$multiedit, undef],
-    "annotate" => [\$annotate, undef]
+    "annotate" => [\$annotate, undef],
+    "xmailer" => [\$use_xmailer, 1]
 );
 
 my %config_settings = (
@@ -327,6 +329,7 @@ sub signal_handler {
 		    "8bit-encoding=s" => \$auto_8bit_encoding,
 		    "compose-encoding=s" => \$compose_encoding,
 		    "force" => \$force,
+		    "xmailer!" => \$use_xmailer,
 	 );
 
 usage() if $help;
@@ -1181,8 +1184,10 @@ sub send_message {
 Subject: $subject
 Date: $date
 Message-Id: $message_id
-X-Mailer: git-send-email $gitversion
 ";
+	if ($use_xmailer) {
+		$header .= "X-Mailer: git-send-email $gitversion\n";
+	}
 	if ($reply_to) {
 
 		$header .= "In-Reply-To: $reply_to\n";

t/t9001-send-email.sh

@@ -1564,4 +1564,37 @@ test_expect_success $PREREQ 'sendemail.aliasfile=~/.mailrc' '
 	grep "^!someone@example\.org!$" commandline1
 '
 
+do_xmailer_test () {
+	expected=$1 params=$2 &&
+	git format-patch -1 &&
+	git send-email \
+		--from="Example <nobody@example.com>" \
+		--to=someone@example.com \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		$params \
+		0001-*.patch \
+		2>errors >out &&
+	{ grep '^X-Mailer:' out || :; } >mailer &&
+	test_line_count = $expected mailer
+}
+
+test_expect_success $PREREQ '--[no-]xmailer without any configuration' '
+	do_xmailer_test 1 "--xmailer" &&
+	do_xmailer_test 0 "--no-xmailer"
+'
+
+test_expect_success $PREREQ '--[no-]xmailer with sendemail.xmailer=true' '
+	test_config sendemail.xmailer true &&
+	do_xmailer_test 1 "" &&
+	do_xmailer_test 0 "--no-xmailer" &&
+	do_xmailer_test 1 "--xmailer"
+'
+
+test_expect_success $PREREQ '--[no-]xmailer with sendemail.xmailer=false' '
+	test_config sendemail.xmailer false &&
+	do_xmailer_test 0 "" &&
+	do_xmailer_test 0 "--no-xmailer" &&
+	do_xmailer_test 1 "--xmailer"
+'
+
 test_done