Disable querying of external nameservers during build tests.

Set RES_NAMESERVERS and RES_OPTIONS in debian/rules, additionally patch
t/05_api_4.t, which has nameservers hardcoded, to honour NO_NETWORK_TESTING.

Thanks: Sven Mueller for the bug report.
Closes: #1055023

3 files changed, 30 insertions, 0 deletions

diff --git a/debian/patches/no_network.patch b/debian/patches/no_network.patch
new file mode 100644
index 0000000..df05c75
--- /dev/null
+++ b/debian/patches/no_network.patch
@@ -0,0 +1,25 @@
+Description: skip test with external nameservers if NO_NETWORK_TESTING is set
+Origin: vendor
+Bug-Debian: https://bugs.debian.org/1055023
+Forwarded: not-needed
+Author: gregor herrmann <gregoa@debian.org>
+Last-Update: 2023-10-29
+
+--- a/t/05_api_4.t
++++ b/t/05_api_4.t
+@@ -61,12 +61,15 @@
+     timeout => 0.001,
+   );
+ 
++SKIP: {
++  skip "NO_NETWORK_TESTING set", 1 if $ENV{NO_NETWORK_TESTING};
+   $resolver->resolve(
+     event   => "response",
+     host    => "google.com",
+     context => $request++,
+     nameservers => ['8.8.8.8', '8.8.4.4'],
+   );
++};
+ }
+ 
+ sub got_response {
diff --git a/debian/patches/series b/debian/patches/series
index be173b6..5b7318d 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -1 +1,2 @@
 net-dns-1.38-deprecations.patch
+no_network.patch
diff --git a/debian/rules b/debian/rules
index 2d33f6a..10c7296 100755
--- a/debian/rules
+++ b/debian/rules
@@ -2,3 +2,7 @@
 
 %:
 	dh $@
+
+override_dh_auto_test:
+	# disable DNS queries
+	RES_NAMESERVERS="" RES_OPTIONS=attempts:0 NO_NETWORK_TESTING=1 dh_auto_test