From 78bcddf624996bb7d8272ada4a9db30cc4b4bd7d Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Thu, 15 Jun 2023 12:34:34 +0100
Subject: [PATCH] debian/update-build-deps: Add --check mode

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 debian/update-build-deps | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/debian/update-build-deps b/debian/update-build-deps
index 856af2c..2c19049 100755
--- a/debian/update-build-deps
+++ b/debian/update-build-deps
@@ -1,6 +1,11 @@
 #!/usr/bin/perl -w
 use strict;
 
+our $mode =
+  "@ARGV" eq '--check' ? 'check' :
+  "@ARGV" eq '' ? 'install' :
+  die "$0: bad usage\n";
+
 open I, "debian/control" or die $!;
 open O, ">debian/control.new" or die $!;
 
@@ -41,4 +46,9 @@ while (<I>) {
 
 I->error and die $!;
 close O or die $!;
-rename "debian/control.new", "debian/control" or die $!;
+
+if ($mode eq 'install') {
+  rename "debian/control.new", "debian/control" or die $!;
+} else {
+  exec qw(diff -u), "debian/control", "debian/control.new";
+}
-- 
2.30.2