Hold the resolver's configuration guards in the dnsmasq module's tests (issue 1966)

Moved from mesh-sdk's catalogue tests, which read a literal the file no longer has.

Claude-Session: https://claude.ai/code/session_01JG73KEq4zoDfM9WtYpcQgZ

modules/dnsmasq/cmd/dnsmasq-tools/templates_test.go

@@ -162,3 +162,43 @@ func TestUpstreamsAreConfigValues(t *testing.T) {
 		t.Error("dnsmasq.conf lost no-resolv")
 	}
 }
+
+// The resolver's configuration keeps what made every earlier resolver of the mesh go wrong (moved from mesh-sdk's
+// catalogue tests, which could not follow the file when its upstreams became settings): it answers on the private
+// address and loopback only, by address and never by interface (novox/hq issue 110), binds once and never
+// dynamically (issue 348), reads no hosts file and no operator's files (ADR 0199), and takes none of the addresses
+// systemd-resolved holds. no-resolv and the two server lines are held by TestUpstreamsAreConfigValues.
+func TestTheResolverConfigurationKeepsItsGuards(t *testing.T) {
+	raw, err := os.ReadFile(filepath.Join(moduleDir, "files", "dnsmasq.conf"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	config := "\n" + string(raw)
+	for _, want := range []string{
+		"\nlisten-address=127.0.0.1\n", "\nlisten-address=${machine:address}\n",
+		"\nno-hosts\n", "\nconf-file=/etc/mesh-resolver/zones.conf\n", "\nconf-file=/etc/mesh-resolver/nodes.conf\n",
+		"\ndomain-needed\n", "\nbogus-priv\n", "\nbind-interfaces\n",
+	} {
+		if !strings.Contains(config, want) {
+			t.Errorf("the resolver's configuration lacks %q", strings.TrimSpace(want))
+		}
+	}
+	for _, line := range strings.Split(config, "\n") {
+		for _, never := range []string{"bind-dynamic", "interface=", "conf-dir=", "addn-hosts=", "listen-address=${setting:",
+			"listen-address=127.0.0.53", "listen-address=127.0.0.54", "listen-address=127.0.0.55"} {
+			if strings.HasPrefix(line, never) {
+				t.Errorf("the resolver's configuration says %q", line)
+			}
+		}
+	}
+	// The zone and node files the configuration reads are the ones the manifest's facts place.
+	manifest, err := os.ReadFile(filepath.Join(moduleDir, "module.json"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, p := range []string{"/etc/mesh-resolver/zones.conf", "/etc/mesh-resolver/nodes.conf"} {
+		if !strings.Contains(string(manifest), `"path": "`+p+`"`) {
+			t.Errorf("the manifest places no file at %s, which the configuration reads", p)
+		}
+	}
+}