send-email: allow aliases in patch header and command script outputs

Interpret aliases in:

  -  Header fields of patches generated by git format-patch
     (using --to, --cc, --add-header for example) or
     manually modified. Example of fields in header:

      To: alias1
      Cc: alias2
      Cc: alias3

  -  Outputs of command scripts specified by --cc-cmd and
     --to-cmd. Example of script:

      #!/bin/sh
      echo alias1
      echo alias2

Signed-off-by: Remi Lespinet <remi.lespinet@ensimag.grenoble-inp.fr>
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-send-email.perl

@@ -1535,7 +1535,9 @@ foreach my $t (@files) {
 		($confirm =~ /^(?:auto|compose)$/ && $compose && $message_num == 1));
 	$needs_confirm = "inform" if ($needs_confirm && $confirm_unconfigured && @cc);
 
+	@to = expand_aliases(@to);
 	@to = validate_address_list(sanitize_address_list(@to));
+	@cc = expand_aliases(@cc);
 	@cc = validate_address_list(sanitize_address_list(@cc));
 
 	@to = (@initial_to, @to);

t/t9001-send-email.sh

@@ -1552,6 +1552,66 @@ test_expect_success $PREREQ 'sendemail.aliasfile=~/.mailrc' '
 	grep "^!someone@example\.org!$" commandline1
 '
 
+test_expect_success $PREREQ 'alias support in To header' '
+	clean_fake_sendmail &&
+	echo "alias sbd  someone@example.org" >.mailrc &&
+	test_config sendemail.aliasesfile ".mailrc" &&
+	test_config sendemail.aliasfiletype mailrc &&
+	git format-patch --stdout -1 --to=sbd >aliased.patch &&
+	git send-email \
+		--from="Example <nobody@example.com>" \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		aliased.patch \
+		2>errors >out &&
+	grep "^!someone@example\.org!$" commandline1
+'
+
+test_expect_success $PREREQ 'alias support in Cc header' '
+	clean_fake_sendmail &&
+	echo "alias sbd  someone@example.org" >.mailrc &&
+	test_config sendemail.aliasesfile ".mailrc" &&
+	test_config sendemail.aliasfiletype mailrc &&
+	git format-patch --stdout -1 --cc=sbd >aliased.patch &&
+	git send-email \
+		--from="Example <nobody@example.com>" \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		aliased.patch \
+		2>errors >out &&
+	grep "^!someone@example\.org!$" commandline1
+'
+
+test_expect_success $PREREQ 'tocmd works with aliases' '
+	clean_fake_sendmail &&
+	echo "alias sbd  someone@example.org" >.mailrc &&
+	test_config sendemail.aliasesfile ".mailrc" &&
+	test_config sendemail.aliasfiletype mailrc &&
+	git format-patch --stdout -1 >tocmd.patch &&
+	echo tocmd--sbd >>tocmd.patch &&
+	git send-email \
+		--from="Example <nobody@example.com>" \
+		--to-cmd=./tocmd-sed \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		tocmd.patch \
+		2>errors >out &&
+	grep "^!someone@example\.org!$" commandline1
+'
+
+test_expect_success $PREREQ 'cccmd works with aliases' '
+	clean_fake_sendmail &&
+	echo "alias sbd  someone@example.org" >.mailrc &&
+	test_config sendemail.aliasesfile ".mailrc" &&
+	test_config sendemail.aliasfiletype mailrc &&
+	git format-patch --stdout -1 >cccmd.patch &&
+	echo cccmd--sbd >>cccmd.patch &&
+	git send-email \
+		--from="Example <nobody@example.com>" \
+		--cc-cmd=./cccmd-sed \
+		--smtp-server="$(pwd)/fake.sendmail" \
+		cccmd.patch \
+		2>errors >out &&
+	grep "^!someone@example\.org!$" commandline1
+'
+
 do_xmailer_test () {
 	expected=$1 params=$2 &&
 	git format-patch -1 &&